Upload
others
View
6
Download
0
Embed Size (px)
Citation preview
Funded under European Union’s Horizon 2020 research and innovation programme - Grant agreement No 724029
September 19 Page 1 of 80 SA_Task5.5 _TUNISIA
Project SAFER AFRICA
Work Package: WP5 – Road safety and traffic management capacity reviews
Deliverable: D5.19 - Assessment of Standards for Road design and vehicle safety in TUNISIA: Proposed amendments and enabling project plans
Version FINAL
Date 5 September 2019
Report authors: A. Maghraoui, S. Zammataro, E. Fernandez, D. Sengupta
2
Document Control Sheet
Document title Assessment of Standards for Road design and vehicle safety in TUNISIA: Proposed amendments and enabling project plans
Work package: WP5 – Road safety and traffic management capacity reviews
Deliverable D5.19
Version FINAL
Last version date 5 September 2019
Status
File Name SA_Task5.5_TUNISIA_FINAL
Number of pages 80
Dissemination level Public
Responsible author A. Maghraoui, S. Zammataro, E. Fernandez, D. Sengupta
Editors
Versioning and Contribution History
Version Date Author/Editor Contributions Description / Comments
First Draft 2 August A. Maghraoui Partial draft
Second Draft
6 August S. Zammataro, E. Fernandez
Complement draft
Third Draft
20 August S. Zammataro Revise and amend
Third Draft 29 August
D. Sengupta, A. Maghraoui Review and edits
Third Draft 30 August
J. Funk Editing
Final Draft
5 September S. Zammataro Comments from internal review processed
Funded under European Union’s Horizon 2020 research and innovation programme - Grant agreement No 724029
September 19 Page 3 of 80 SA_Task5.5 _TUNISIA
Table of Contents
1 Introduction .............................................................................................................................. 7
1.1 Road design standards ........................................................................................................... 7
1.2 Vehicle standards ................................................................................................................ 7
2 Consolidation of the capacity review and literature results ................................................... 9
2.1 Safe Vehicles ...................................................................................................................... 9
2.2 Road design practices ....................................................................................................... 10
2.2.1 Current road network .............................................................................................. 10
2.2.2 Road safety design and operational checks ............................................................. 11
2.2.3 Speed limits in Tunisia ............................................................................................. 12
3 Assessment of vehicle and road design standards and legislation ....................................... 13
3.1 Vehicle standards................................................................................................................. 13
3.1.1 Comparison with international vehicle standards and recommendations to improve conformity and uniformity ....................................................................................................... 15
3.2 Geometric design standards for roads ............................................................................... 16
3.2.1 Perceived importance of design elements ................................................................... 17
3.2.2 Importance of design factors in Tunisian guidelines ................................................22
4 Prioritising the challenges for safe vehicle and road design standards in Tunisia .............. 25
4.1 Vehicle design standards ................................................................................................... 25
4.1.1 Institutional level ......................................................................................................... 25
4.1.2 Organisational level................................................................................................. 25
4.1.3 Operational level ......................................................................................................... 25
4.2 Road design standards ...................................................................................................... 25
4.2.1 Prioritising road design elements for guidelines for single carriageway rural roads in Tunisia. 26
4.2.2 Prioritising road design elements for guidelines for dual carriageway rural roads in Tunisia. 27
5 Development of an overall prioritisation strategy and formulation of the most promising improvement opportunities for vehicle and road design standards in Tunisia.......................... 29
5.1 Vehicle design standards .................................................................................................. 29
5.1.1 Diagnosis .................................................................................................................... 29
5.1.2 Support project ........................................................................................................... 32
4
5.2 Geometric design standards ............................................................................................. 32
5.2.1 Single carriageway rural roads ..................................................................................... 33
5.2.2 Dual carriageway roads ........................................................................................... 38
6 Recommendations for improvement projects/practices in Tunisia ...................................... 45
6.1 Road design standards ...................................................................................................... 45
6.2 Recommendations for improvement of vehicle standards ............................................... 46
7 References .............................................................................................................................. 47
8 Appendixes ............................................................................................................................ 49
8.1 SaferAfrica assessment of the relevance for safety of Intersafe design items to Tunisian design guidelines ......................................................................................................................... 49
8.1.1 Interurban single carriageway roads ........................................................................... 49
8.1.2 Interurban dual carriageway motorways ...................................................................... 53
8.2 Degree to which Intersafe geometric design items have been covered in Tunisian guidelines 58
8.2.1 Interurban single carriageway roads items mentioned and rating ........................... 58
8.2.2 interurban dual carriageway motorways: items mentioned and rating ................... 68
8.3 Scoring and prioritising ..................................................................................................... 79
8.3.1 Single carriageway roads ............................................................................................. 79
8.3.2 Dual carriageway roads ...........................................................................................80
5
ABBREVIATIONS AND ACRONYMS
ABS Anti-Skid Braking System
APRP Annual Public Roads Programme
ASIRT Association for Safe International Road Travel
ATTT Agence Technique du Transport Terrestre – Technical Agency for Land Transport
AU African Union
BAC Blood Alcohol Content
CITA International Motor Vehicle Inspection Committee
CRS Civil Registration Services
EMS Emergency Medical Services
EMT Emergency Medical Technician
EOC Emergency Operation Centre
EU European Union
FBO Faith Based Organization
FY Financial Year
GDP Gross Domestic Product
HGV Heavy Goods Vehicles
HR Human Resource
IAC Inter-Agency committee
iRAP International Road Assessment Programme
IRF International Road Federation
IRTAD International Road Traffic and Accident Database
ITF International Transport Federation
JAES Joint Africa-EU Strategy
JICA Japan International Cooperation Agency
LMIC Low- and Middle-Income Countries
MoH Ministry of Health
MTP Medium Term Plans
NCAP New Car Assessment Programme
NDMU National Disaster Management Unit
NGO Non-governmental organizations
NHTSA National Highway Traffic Safety Administration
NTSA National Transport and Safety Authority
OECD Organisation for Economic Co-operation and Development
PHTLS Pre-Hospital Trauma Life Support
PSV Public Service Vehicle
6
PVS Public service vehicles
RES Resolution
RSM Road Safety Management
RSMCR Road Safety Management Capacity Review
RTA Road traffic Accident
SER Self-Explaining Roads
SLA Service Level Agreements
SOE State Operated Enterprises
SPI Safety Performance Indicators
SPR Special Purpose Roads
SWOT Strengths, Weaknesses, Opportunities, and Threats
SWOV Stichting Wetenschappelijk Onderzoek Verkeersveiligheid
SWRW Safe Way Right Way
TIMS Transport Integrated Management System
TTTFP Tripartite Transport and Transit Facilitation Programme
UK United Kingdom
UN United Nations
UNECA United Nations Economic Commission for Africa
UNECE United Nations Economic Commission for Europe
UNRSC United Nations Road Safety Collaboration
USA United States of America
VOSL Value of Statistical Life
WB World Bank
WP Work Package
7
1 Introduction Road and vehicle design standards form the backbone for setting the requirements with respect to road planning, design, maintenance and operation, and for allowing vehicles to operate and participate in the traffic on public roads. Internationally both these domains have evolved, and various standards organisations have adopted international treaties and requirements to provide some form of standardisation and uniformity when it comes to road and vehicle design. These treaties not only serve to improve the quality of roads and vehicles, but more importantly aim to ensure that these provide optimal levels of safety to eliminate/reduce crashes, and to ensure that the effects of crashes on injuries are minimised. In terms of both road and vehicle standards countries on the African continent have been found to be lagging behind most international standards and practices (World Health Organisation, 2015). Generally, vehicles in African countries are old, poorly maintained and regulated. The same applies for the road networks in many African countries and this has added to the growing road safety problem being experienced in many African nations.
1.1 Road design standards Roads, and particularly public roads are designed and built according to set standards. These are generally adopted by authorities responsible for road infrastructure in a country and provide a basis for stipulating quality standards for roads.
Road design standards apply to the design, construction, maintenance and operation of roads and are generally supported by guidelines and standards for aspects related to road signs and markings, signalisation, fencing and verge management and others. In the context of SaferAfrica, and in particular Task 5.5 of Work Package 5, the focus is particularly on the (geometric) design of roads, which is closely linked to road safety, and is intended to ensure that roads are designed to provide adequate levels of safety given the selected designs speeds. This report will not deal with aspects related to pavement design and construction, bridge and tunnel design and construction, materials etc. since these fall outside the scope of this study.
Geometric design of roads relates to the positioning of the road and its elements in a given physical (and financial) space with the aim of optimising the efficiency and safety of traffic that is expected to use the road and with minimal impact to the environment. Geometric design of roads deals with the horizontal and vertical alignment of the road and its cross-section and intends to ensure that a roadway is built in such a way that it does not surprise road users and allows them enough time/space to correct for errors or avoiding dangerous situations.
1.2 Vehicle standards Road vehicle standards intend to set parameters for the physical and mechanical state of road going vehicles during their operational life. These standards regulate the use of vehicles on public roads and put demands on the construction and maintenance of vehicles, as well as on features that are designed to protect occupants and other road users. In most cases, vehicle manufacturers design and build vehicles to comply with vehicle standards adopted by countries or regulated by international treaties, such as those of the United Nations, or those adopted by countries in the EU. These standards not only govern requirements for new vehicles, but more importantly should regulate the fitness of older vehicles.
8
Any comprehensive road safety policy shall contain provisions to ensure that vehicles entering into the fleet fulfil some minimum requirements, and those requirements are kept, in a reasonable way, as long as the vehicle is on the road. Unfortunately, many African countries have limited restrictions on the import of second-hand vehicles.
Vehicles may enter a country as new or used, and it is therefore necessary to set the criteria to accept vehicles in both cases. Regardless of the usage of the vehicle, all countries submit them to registration. This administrative procedure is the right moment to assess vehicles fulfil the minimum standards required in that country.
Once vehicles are on the road, many things may happen: breakdowns, tear and wear, modifications, crashes, maintenance, change of use1, etc. It is necessary to set up the right scheme to ensure that vehicles keep their performances above a minimum level. The two key tools for roadworthiness are unexpected road-side inspection and periodical vehicle inspection.
Since the conception of vehicles has a global approach, it makes sense to take advantage of the already existing international frameworks of vehicle standardisation, and in particular of the UN Agreements of 1958 and 1998 for new vehicles and 1997 for periodic technical inspections. Standards are already defined and available.
There are many advantages to adhere to an already existing vehicle standardisation scheme:
The European Union and many other regions in the world are already applying them: vehicle manufacturers are used to UN Regulations and setting up additional requirements may increase the price of vehicles;
It is not necessary for countries applying the standards to build expensive testing facilities since they can recognise the tests and approvals undertaken in other parts of the world;
Countries may decide the degree of implication they want to have with standards: full mutual recognition or just acceptance
Countries can always keep their sovereignty regarding the entrance of vehicles
Disclaimer
All reasonable efforts have been taken to identify the right regulatory framework, although there is not complete certainty that all legal texts are considered for each country. Additional or different legal documents may change the considerations of this document. Authors cannot be liable in that case.
1 Example of change of use: the same car is submitted to quite different conditions if used privately or as a taxi
9
2 Consolidation of the capacity review and literature results
2.1 Safe Vehicles
At the end of 2015, Tunisia had nearly 1,922,000 vehicles on the road. 60% of vehicles in circulation were private cars and 22% vans. The rest was divided between farm machinery and vehicles, mixed cars, trucks and motorcycles (SaferAfrica Deliverable 5.6 - Capacity Review Tunisia).
According to the statistics from the ATTT (Agence Technique des Transports Terrestres – Technical Agency for Land Transport), the motor vehicles fleet in Tunisia is growing annually at a rate of approximately 70 to 80,000 vehicles. The light vehicle (LV) segment accounts for the largest share of the automobile market in Tunisia, with approximately 96% of total sales. (SaferAfrica Deliverable 5.6 - Capacity Review Tunisia).
Light vehicles (LVs) driving in Tunisia come from the official and parallel markets. The parallel market accounts for 40% of car sales and the increase has been steady. This explains partly the aging fleet. The number of vehicles over 15 years old is estimated at approximately 30 to 40% of the entire fleet in circulation.
The Capacity Review of Tunisia identifies the ATTT as the governmental body responsible for setting vehicle standards and for undertaking vehicle inspections. It is a non-administrative public establishment considered as a public enterprise. (Governed by law No. 98-108 of 28 December 1998, the ATTT took over from the Agency of Vehicle Roadworthiness Visits created in 1995 under law No. 95-61 of 3 July 1995).
Vehicle roadworthiness tests are mandatory. In 2016, the regulation defining frequency of testing changed. According to the new rule, vehicles undergo their first roadworthiness tests starting in the fourth year after being put into circulation. After the fourth year, roadworthiness tests are performed every two years and then annually starting from the tenth year. Moreover, the new law of 2016 has made the certification issued after technical inspection mandatory in order to be able to ensure the vehicle. The change of law was dictated by the fact that an estimated 300,000 vehicles were in circulation despite the fact that they had not passed the mandated technical inspection.
10
2.2 Road design practices For road safety it is of paramount importance that the road network is provided with the necessary safety features to ensure the safety of its users and the safety between users. To facilitate that, road networks must be systematically and logically classified (functional), road designs must comply not only with design standards but also with safety standards, road users must comply with restrictions set to ensure safe operation and engineers must ensure that the roads are maintained at a level that these standards are not compromised. From a safe systems perspective, the following aspects require specific attention:
Comprehensive safety standards and rules and performance targets for the planning, design, operation and use of roads;
Aligning speed limits with safe systems design principles;
Ensuring that compliance regimes are in place and that users adhere to the safety rules and standards;
Safety standards and rules considering the specific needs of high-risk road user groups.
A safe systems approach to road design ensures roads which are designed and constructed to reduce the risk of crashes (i.e. the design of the road will not be directly attributable to a crash) and where crashes do occur, the severity of the crash will be minimised. Roads typically have features such as adequate clear zones, no roadside hazards; breakaway constructions, safe barriers, no conflicts between opposing traffic, slow and fast traffic physically separated (in time and/or space), etc..
In Tunisia, the strategic planning mission for transport and road infrastructures is the responsibility of the Ministry of Transport. More precisely, the Ministry is in charge of establishing, maintaining and developing a comprehensive, integrated and coordinated transport system that contributes to promoting sustainable economic and social development and ensures that transport needs are met for people under the best possible conditions, notably in terms of safety, security, cost, quality and environmental protection.
On the regional level, the Ministry of Transport is represented in all the governorates through the regional directorates that oversee compliance with the national road mobility targets. The governorate draws up the Governorate’s Development Scheme in which it lays down planning for the road network and the organization of regional infrastructures. This plan must be approved by the regional council.
On the municipal level, the municipalities are asked to design Traffic Plans consistent with the regional and national plans and in harmony with the delegation’s targets. These traffic plans translate the municipal mobility policy and the measures for intervention by the municipalities for infrastructures. The Urban Mobility Plans and Traffic Plans must be approved by the municipal council (SaferAfrica Deliverable 5.6 - Capacity Review Tunisia).
2.2.1 Current road network
The current road network of Tunisia comprises 19 750 km of roads, of which 12 750 km is paved and 360 km is classified as motorways (Joël Yerpez & Nesrine Bouhamed, 2018).
The network is managed by the Ministry of Equipment, Housing and Spatial Planning. National roads, approximately 3,940 km long, cover long axes and run through several Tunisian governorates and characterised by high traffic volumes. Secondary roads, covering regional axes with less traffic, are called "regional roads". They represent approximately 5,120 km. Local roads form the local road network of each governorate and cover about 2,450 km. Another 1,240 km of unclassified roads and
11
more than 13,000 km of agricultural roads / rural roads unpaved. (SaferAfrica Deliverable 5.6 - Capacity Review Tunisia).
The motorway network is under development. The largest motorway axis connects Bizerte, Tunis, Sousse and Sfax along the coast along highways 1 and 4. Highways serve dynamic economic areas. The hinterland does not benefit from such a high-performance infrastructure. In July 2014, the World Bank granted a $ 230 million loan to rehabilitate highways. The project aims to open up the most remote and precarious areas in order to promote trade, reduce unemployment and limit economic disparities between regions.
At the national level, the Ministry of Equipment and Housing (MEH) is in charge of the maintenance of the road network through the Directorate of Operations and Road Maintenance (DEER) and the Directorate of Equipment (DM). DEER draws up the general framework for maintenance and keeps the collection of road data and traffic statistics up to date.
The Ministry is also represented throughout the Tunisian territory by its Regional Directorates to plan and carry out the maintenance of national and regional highways in collaboration with the governorate. The development of extra-communal and rural tracks is also the responsibility of the Ministry, which distributes the maintenance budget among the Regional Directorates, ensures the analytical follow-up and the control of the works.
Municipalities are responsible for the work and maintenance of local roads and sidewalks. A collaboration may be necessary between the urban communes and the Ministry if the maintenance concerns a road with common interests. Lack of financial resources and lack of coordination can cause road repair quality problems. The municipality is further responsible for informing citizens of road works and for ensuring preventive road safety measures are taken.
Overall, the Tunisian road network is relatively developed, with big cities being connected by a fairly dense network. The roads are classified according to their category and their functionality. High-speed traffic is supported on “motorways”, although this network is still relatively limited and does not yet connect all metropolitan areas. The major links are provided by national roads which represent nearly 30% of the network of classified roads. Secondary roads cover regional axes with less traffic, and are classified as regional roads. Despite the relative development of the network, road conditions remain below expectation according to road safety institutions and users/citizens.
2.2.2 Road safety design and operational checks
On the basis of the information available at the moment of drafting this report, Tunisia appears to lack a local manual or guidelines2. The design and construction of new roads, and to an extent the reconstruction and rehabilitation of existing roads, is carried out using the French standards and guidelines.
There seems to be no established procedure or methodology that outlines the steps to be followed for road design and validation. Road safety is addressed in some feasibility studies, but not structurally in the design phases (i.e. designs are checked but not against specific road safety design criteria). Recently, the obligation to perform a Road Safety Audit has been introduced for new projects. Despite this positive development, audits are still far from being a standard practice. They are still incidentally
2 Despite several attempts, it has not been possible to obtain feedback from the tunisian authorities on this.
12
carried out (mainly as part of donor funded projects). Road safety inspections are also not routine, nor structurally carried out.
Although specific road safety guidelines have been prepared for African countries by the African Development Bank (African Development Bank, 2014a, 2014b, 2014c), these do not seem to have been adopted in Tunisia.
Finally, in addition to the limited financial resources, the human resources are not always available to deal with the problems, nor do they always have the required knowledge, training and experience.
2.2.3 Speed limits in Tunisia
No instructions or procedure for determining speed limits was found during the examination of the available documents, both in urban and interurban areas. Nevertheless, the geometric design guidelines provide speeds which serve as a basis for the category choice. For motorways, the speed is limited to 130 Km/h and 110 Km/h, respectively, for the L1 and L2 categories. Dual carriageway roads are limited to 110 Km/h or 90 Km/h. The speed limit on single carriageway roads is 80 Km/h or 60 Km/h.
An internet check of the speed limit signs installed along the roads shows that the speed on highways is limited to 110 Km/h (reduced to 90 Km/h in rainy weather). On the rest of the interurban networks the speed is limited to 90 Km/h, except at intersections and along sections that have some difficult geometric features. In urban areas, the speed is limited to 50 Km/h. But existing roads are not regularly appraised to determine whether the posted speed limits are still valid.
There are no indications that the safe systems approach is being applied in terms of managing safe speeds, not from an engineering nor from an enforcement perspective. The safe system approach embodies safe speed which necessitates the establishment of speed limits according to the features of the road and roadside, as well as speed enforcement and education measures. This does not seem to be the case for Tunisia.
13
3 Assessment of vehicle and road design standards and legislation
3.1 Vehicle standards The regulatory framework of Tunisia is available in the document “Code de la Route et ses textes d’application, 2017”3 – Road Act and its complementary regulations, 2017. It contains relevant texts setting up requirements both for new and in-use vehicles, in a similar approach to some EU countries.
The current Road Act4 was approved in 1999 replacing the version released in 1978. The 1999 Road Act has been updated since, however it keeps the same approach as the version which was adopted.
The most relevant items are listed below:
Classification of vehicles: it is very similar to the one used in the European Union and the UN conventions. This facilitates the introduction of international standards;
The law (Art 61) indicates that precise rules will be defined in the appropriate decrees. Art 67 has the same approach for agricultural tractors and machinery, and Art 71 for motorcycles. Therefore, all road vehicles are considered;
Art 62 defines the homologation as an activity of the Ministry of Transport, to be developed as well by ministerial orders. It also defines how to handle important modifications of vehicles;
Art 64 regulates the registration of vehicles, again to be detailed in a ministerial order, and Art 65 establishes the obligation for vehicle owners to keep them roadworthy and to submit
them to periodical inspections.
Altogether, the Road Act can be considered as appropriately covering all the relevant items related to vehicles, including both road safety and environmental protection.
Additional legal documents in Tunisia related to vehicles are the following ones:
Decree 2004-2236, of September 21st, 2004. This Decree sets the categories two-, three-wheelers and quadricycles defining those submitted to approval and registration. It applies to mopeds, motorcycles, three-wheelers and quadricycles. Decree 20014/2236 does not precisely define the standards to apply.
Decree 2000-147, of January 24th, 2000. This document establishes the technical rules for the equipment and furnishing of vehicles. The content of the Decree is split into several relevant items for cars, vans, trucks, buses, trailers, agricultural vehicles, road machinery, mopeds, motorcycles, tricycles and quadricycles:
Dimensions, weights and tyres. Approved tyres according to recognised standards (however there is no precise list). Engine and its systems, including requirements for gaseous emissions and noise. There is
potential to give more details about this matter. Lighting and light-signalling systems Fuel tanks and pipes. Conditions for batteries.
3 https://www.droit-afrique.com/uploads/Tunisie-Code-2017-route.pdf
4 Law – Loi 99-71, of July 26th, 1999
14
Steering wheel, controls, visibility, speed control and tachographs. Brakes. Chassis identification Safety belts and anchorages, but not including a full requirement of 3-point safety belts for
all seats Child seats are not mandatory Rear and side underrun protection prescribed, but performances not defined
Altogether, the structure of the Decree 2000-147 identifies most of the essential items of the vehicle’s safety and environmental performance. However, it does not identify the precise standards to follow.
Decree 2000-148, of January 24th, 2000 sets the periodicity and procedures for vehicle inspection. It also obliges vehicle owners to keep their vehicle roadworthy regardless of the inspections and allows additional unexpected controls by the police. The annex contains a list of the checks to undertake and the identification and classification of defects.
Decree 2000-155, of January 24th, 2000 defines the equipment to control vehicles, but only in the cases where equipment is used to establish infringements. It does not contain requirements for calibration, metrological control or model approval.
Additional interesting legal documents include:
Decree 2002-2016, of September 4th, 2002, for LPG powered vehicles. Decree 2002-2017, of September 4th, 2002, for NGC powered vehicles. Ministerial Order of January 25th, 2000 for the registration of vehicles, including the need of
the Certificate of Conformity and vehicle approval. Ministerial Order of January 25th, 200o for the approval of vehicles defining:
o Application to all road vehicles o Type approval o Individual approval o The Ministry of Transport as responsible for approval o The need for tests performed by recognised technical centres
Altogether, the Tunisian framework for vehicles is well structured and one of the most complete in Africa. The possibilities for completion are found in the following areas:
A precise definition of the standards to follow Definition of responsibilities and establishment of the infringement regime Requirements for inspectors Requirements for equipment Requirements to guarantee the quality
Tunisia has adhered to the 1958 UNECE Agreement for the approval of vehicles on January 1st, 20085 with the country code E58. The Government has designated the ATTT as the approving authority for several UNECE regulations6. The most remarkable ones are:
UNECE Regulation 13: H: brakes
5 https://www.unece.org/fileadmin/DAM/trans/doc/2019/wp29/ECE-TRANS-WP.29-343-Rev.27.pdf 6 https://www.unece.org/fileadmin/DAM/trans/doc/2019/wp29/ECE-TRANS-WP.29-343-Rev.27-Add.1.pdf
15
UNECE Regulation 101: emissions of CO2, fuel consumption and electric consumption UNECE Regulation 105: transport of dangerous goods (vehicle design) UNECE Regulation 107: general requirements for buses and coaches (categories M2 and M3) UNECE Regulation 115: vehicles using LPG and CNG as fuel
ATTT has also been designated as technical service in charge of performing the test on the vehicles. The reports of those tests are used by authorities to grant the homologation. Despite having appointed a technical service, Tunisia hasn’t defined for which specific regulations ATTT is appointed as technical service.
3.1.1 Comparison with international vehicle standards and recommendations to improve conformity and uniformity
The natural benchmark at international level for the comparison of the standardisation schemes for vehicles is the Agreement of the United Nations Economic Commission for Europe (UNECE). Although the name refers to Europe, any UN country may participate, and many non-European countries already do.
The WP.29, belonging to UNECE, manages three different agreements:
Agreement of 19587: Agreement concerning the Adoption of Harmonized Technical United Nations Regulations for Wheeled Vehicles, Equipment and Parts which can be Fitted and/or be Used on Wheeled Vehicles and the Conditions for Reciprocal Recognition of Approvals Granted on the Basis of these United Nations Regulations.
Agreement of 19988: Global technical regulations for wheeled vehicles, equipment and parts which can be fitted and/or be used on wheeled vehicles.
Agreements of 19979: Agreement Concerning the Adoption of Uniform Conditions for Periodical Technical Inspections of Wheeled Vehicles and the Reciprocal Recognition of Such Inspections.
The first two agreements, 1958 and 1998, define the standards for new vehicles. The analysis of the differences between them is beyond the scope of this document, however both set a scheme for vehicle approval and mutual recognition of the approvals between countries. As mentioned above, Tunisia has adhered 1958 UNECE Agreement for the approval of vehicles on January 1st, 200810 with the country code E58.
The third agreement, the one of 1997, defines the standards to apply to vehicles in use to ensure their roadworthiness both from the safety and the emissions point of view. It also contains provisions for the mutual recognition that may be used in Africa, in particular in those regions with significant volumes of international traffic, like the corridors or the roads from land-locked countries to harbours.
UNECE agreements pose a readily available off-the-shelf solution for vehicle standardisation. Even the European Union’s scheme for vehicle approval also refers to the UNECE agreements. Here is a list of the main advantages of the system:
7 https://www.unece.org/fileadmin/DAM/trans/main/wp29/wp29regs/2017/E-ECE-TRANS-505-Rev.3e.pdf 8 https://www.unece.org/fileadmin/DAM/trans/main/wp29/wp29wgs/wp29gen/wp29glob/tran132.pdf 9 https://www.unece.org/trans/main/wp29/wp29wgs/wp29gen/wp291997.html 10 https://www.unece.org/fileadmin/DAM/trans/doc/2019/wp29/ECE-TRANS-WP.29-343-Rev.27.pdf
16
Vast readily available compendium of vehicle standards, covering all aspects of vehicles: 147 regulations according to the agreement of 1958, 20 Global Technical Regulations (GTR) according to the agreement of 1998 and 4 rules according to the agreement of 1997.
A group of experts working in the field since the late 1950s. Unique worldwide forum of vehicle regulations in which any UN country can be influential by
voting. Agreements can be formally ratified, with all the implications of international law, or just
recognised at the country level. Agreements can be adapted. Countries keep their sovereignty under all circumstances. Vehicle manufacturers already know how to produce according to those standards. Using non-common standards requires tailored designs, and therefore, vehicles become
more expensive. Countries do not need to develop testing facilities; they can use the tests already done in other
parts of the world.
In the case of Tunisia, there is already a well-defined framework: the Road Act. The country may decide to develop all the precise technical details by itself, to wait for regional development, or to take off the shelf all the existing international material.
3.2 Geometric design standards for roads The degree to which guidelines are applied varies considerably between road authorities and between different projects. The application of guidelines is related to the available space (to design and build the road) and the distribution of traffic and environmental functions of a road: application can be hindered by lack of space, but also because there is disparity between the designated function of a road and its actual use. Sometimes there may be legitimate grounds to deviate from the guidelines. Furthermore, a traffic engineering design is subject to several preconditions: spatial integration, political choices and interests of those directly involved. Furthermore, in the design process choices must be made that will influence the final result.
It is important to take into account the road safety implications when making design choices. Guidelines worldwide provide limited insight into the relationship between the different design elements and road safety. For example, in the Netherlands, only around 30% of the design elements mention a road safety effect (G. Schermers, Dijkstra, Mesken, & Baan, 2013). It is therefore extremely difficult for the designer (who is rarely a safety specialist) to determine the quantitative road safety effect if it is necessary to deviate from recommendations in the guidelines during the design process. In practice, a qualitative assessment by an expert is therefore important. Such expert judgement may provide more clarity but does not provide conclusive evidence.
Two dimensions were considered in the assessment of road safety in road design guidelines in Tunisia:
The perceived importance of the design elements themselves The extent to which the design elements were included in current guidelines
The INTERSAFE study – Technical Guide on Road Safety for Interurban Roads (ERSF, 1996) was used to provide the basis for the assessment. In this study various geometric design elements were identified and could be used to define 86 separate design features which could be categorised into the primary design elements, namely:
basic assumptions (25 -28 items); alignment (19 -21 items); cross-section (21 -25 items); intersections/interchanges (21 -28 items).
17
The selected criteria (listed in detail in Appendix A for single and dual carriageway roads separately) were reviewed by engineers from the SaferAfrica team and were slightly modified to include additional elements, especially relevant to dual carriageway roads. This increased the total number of design features or items to 89 on single carriageway roads and to 105 on dual carriageway roads.
Seeing that most countries do not have specific geometric design guidelines for urban roads, the assessment focussed on guidelines for rural roads and highways (dual carriageway). Because of some fundamental design differences in these road types, the number of items per primary element also differed.
3.2.1 Perceived importance of design elements
The first step of the assessment was to establish whether local road designers and specialists considered the various design items and elements important from a road safety perspective and necessary to include in the guidelines.
To start with, road safety experts carried out a qualitative assessment of these design items on three aspects: 1) the presumed road safety effect, 2) the degree in which the relation with safety has been validated, and 3) possibilities to further research the specific element where the relationship is not fully developed (research-ability). Then the items were given a quantitative assessment based on a weighting and scoring procedure. A design was given a higher score – and higher research priority – where the amount of available knowledge was smaller, and the road safety effect was greater.
In the following section, the relevance and importance of the individual design items are summarised into the four main design elements (Supporting criteria; alignment; cross-section and intersections).
3.2.1.1 Rural single carriageway roads
When rating the safety effect of the various design elements, the assessor found that more than half of the design items were relevant for road safety in the Tunisian situation, with more than 51% across all elements scoring as being highly relevant. About 35% were deemed moderately relevant and about 13% of design items were found to be of little relevance (Table 1). A detailed reflection showing all the individual elements for rural single carriageway roads is included in Appendix B.
Primary design element
Relevance for safety in guidelines/perceived effect on safety
Small Average High Total
Supporting criteria
3 5 17 25
Alignment 3 6 12 21
Cross-section 6 9 6 21
Intersections 0 11 11 22
Total 12 31 46 89
Percentage 13.48% 34.83% 51.69% 100%
Table 1: Relevance of Intersafe design elements for road safety in Tunisian rural single carriageway road design guidelines
18
The next aspect determined to what extent the assessor found the design item to be acknowledged and described in (international) literature. This aspect assumes that if international literature describes the relationship qualitatively (known effect) that the relationship is well understood and important, whereas if it is only descriptive, the relationship with safety is less important and less understood. This assessment revealed that there were more than 50% of items that, according to the assessor, were described in a quantitative sense in the international guidelines, whereas 10 items (11%) were generally descriptive (Table 2).
Primary design element
Relevance as described in international guideline/literature
Purely descriptive
Qualitative Quantitative Total
Supporting criteria
0 9 16 25
Alignment 4 7 10 21
Cross-section 5 5 11 21
Intersections 1 11 10 22
Total 10 32 47 89
Percentage 11.24% 35.95% 52.81% 100%
Table 2: Perceived relevance of elements as described in international literature/guidelines for the Tunisian situation – single carriageway roads
This result shows some compatibility with an earlier study by SWOV in which selected European road authorities at national level and a larger selection of Dutch road authorities (at all levels) were asked to rate the same criteria. European road authorities believe 21% of the relationships are descriptive in nature, 38% qualitatively described and only 41% quantitatively described in current international guidelines. This small difference between the SaferAfrica and SWOV results may be ascribed to different interpretations of some items of the guidelines.
19
Primary design element
Relevance as described in international guideline/literature
Purely descriptive
Qualitative Quantitative Total
Supporting criteria
2 6 17 25
Alignment 3 11 5 19
Cross-section 4 8 8 20
Intersections 9 7 5 21
Total 18 32 35 85
Percentage 21% 38% 41% 100%
Table 3: Perceived relevance as described in international literature/guidelines according to European and Dutch experts (G. Schermers et al., 2013)
When assessing the degree of difficulty in researching the relationship between road safety and the various design aspects from a Tunisian perspective, the assessor found that the difficulty to research the majority of items (83%) is moderate. Only 8% were difficult to research and 9% easy to research.
Primary design element
To what degree of difficulty is the design aspect researchable
Not/Highly difficult Moderately Easy/not difficult Total
Supporting criteria
4 17 4 25
Alignment 1 16 4 21
Cross-section 1 20 0 21
Intersections 1 21 0 22
Total 7 74 8 89
Percentage 7.86% 83.15% 8.99% 100%
Table 4: The degree to which the relationship between geometric design elements for single carriageway rural roads and safety can be researched from a Tunisian perspective
20
The Tunisian assessment of the “researchability” of the various aspects is different to the results of an earlier study in the Netherlands and Europe (Table 5). The aspects covered under basic criteria were generally deemed more difficult to research in the European assessment, whereas they were deemed moderately researchable in the Tunisian assessment.
Primary design element
To what degree of difficulty is the design aspect researchable
Not/Highly difficult
Moderately Not/Highly difficult Total
Supporting criteria
0 6 19 25
Alignment 2 15 2 19
Cross-section 2 15 3 20
Intersections 1 8 11 20
Total 5 44 35 84
Percentage 6% 52% 42% 100%
Table 5: The degree to which the relationship between design items and safety can be researched from a European perspective (G. Schermers et al., 2013)
3.2.1.2 Rural dual carriageway roads
The same assessment was carried out for rural dual carriageway roads as described in the current Tunisian geometric design guidelines. The assessor found that more than the half (56%) of the primary design elements covered by the Intersafe approach were highly relevant and should be included in geometric design guidelines for rural roads, also in Tunisia (Table 6).
Primary design element
Relevance for safety in guidelines/effect on safety
Small Average High Total
Supporting criteria 7 5 16 28
Alignment 2 8 11 21
Cross-section 2 9 14 25
Intersections 3 7 14 24
Total 14 29 55 98
Percentage 14.29% 29.59% 56.12% 100%
Table 6: Relevance of Intersafe design elements for road safety described in Tunisian geometric design guidelines for rural dual carriageway roads
21
The perceived effect for safety of the primary design elements (and the relevance for guidelines) were rated higher for the Tunisian situation than in the earlier study reported in the Netherlands (G. Schermers et al., 2013). In the European situation these elements were rated (Table 7) as having an average effect on safety, but still relevant. The difference in results could be attributed to the fact that in Europe, generally speaking, the relationship between these items and safety is more common practice and entrenched in the thinking, whereas in Africa this pattern is still emerging and therefore the effect and importance for guidelines are rated more highly than in Europe.
Primary design element
Relevance for safety in guidelines/effect on safety
Small Average High Total
Supporting criteria 6 12 6 24
Alignment 5 6 8 19
Cross-section 6 11 3 20
Intersections 2 12 3 17
Total 19 41 20 80
Percentage 24% 51% 25% 100%
Table 7: Relevance of Intersafe design elements for road safety described in European design guidelines for rural dual carriageway roads
The relationships between the primary design elements and road safety were rated as being quantitatively described in (inter)national literature for more than 55%, while almost 20% were rated as being descriptive, which suggests that some effects cannot be easily incorporated into current Tunisian geometric design guidelines for rural dual carriageway roads (Table 8).
Primary design element
Relevance and nature of description in international guideline/literature
Purely descriptive
Qualitative Quantitative Total
Supporting criteria 6 5 17 28
Alignment 2 5 14 21
Cross-section 7 7 11 25
Intersections 4 8 12 24
Total 19 25 54 98
Percentage 19.39% 25.51% 55.10% 100%
22
Table 8: Perceived relevance of elements as described in international literature/guidelines for the Tunisian situation – dual carriageway roads
According to the Tunisian assessor, most items covered by the primary design elements for rural dual carriageway roads are moderately difficult to research (Table 9 ) and it is therefore not easy to implement the relationships in the guidelines. This result is different to that of the European study (G. Schermers et al., 2013) where the proportion of the items that were deemed highly difficult to research and quantify was higher (50%).
Primary design element
To what degree of difficulty is the design aspect researchable
Not/Highly difficult
Moderately Easy/not difficult
Total
Supporting criteria 5 19 4 28
Alignment 3 18 0 21
Cross-section 0 24 1 25
Intersections 0 23 1 24
Total 8 84 6 98
Percentage 8.16% 85.71% 6.12% 100%
Table 9: The degree to which the relationship between geometric design elements for rural dual carriageway rural roads and safety can be researched from a Tunisian perspective
3.2.2 Importance of design factors in Tunisian guidelines
The second part of the assessment related to the extent to which the selected (Intersafe) geometric design aspects were dealt with in Tunisian guidelines and whether their relationship with road safety was addressed.
As mentioned earlier, Tunisia uses French road design standards and guidelines so there were studied to select and assess design characteristics that are important for road safety. The following guidelines were assessed:
- ICTAAL (Instruction sur les Conditions Techniques d’Aménagement des Autoroutes de Liaison) 2000
- ARP - Note d’information SETRA 2008, vitesse V85 - ICTAVRU (Instruction sur les Conditions Techniques d’Aménagement des Voies Rapides
Urbaines) - Guide conception des accès des VRU type A CERTU
All these documents are drawn up by French Ministry of Equipment and Transport.
3.2.2.1 Single carriageway roads
The assessment of the Tunisian geometric design standards reveals that 71.9% of the items covered by the four primary design elements are covered in the Tunisian guidelines, whilst more than 71% of
23
these items (or 51% of the total design elements) do not mention any safety effects. Where the safety effect is mentioned it is purely descriptive and deviations from the recommended norms are almost not addressed (See Appendix B).
A similar evaluation in the Netherlands revealed that 25% of items were not described in the guidelines although 87% of those that were described did not mention any safety effects (G. Schermers et al., 2013).
This similarity is somewhat expected, given the Tunisian guidelines are finally the French guidelines. These thus represent a European approach to road safety.
Primary design element
Mentioned in Tunisian guidelines Not mentioned
in Tunisian guidelines
Total Without road safety effect
With road safety effect
Supporting criteria 17 1 7 25
Alignment 9 8 4 21
Cross-section 10 4 7 21
Intersections 10 5 7 22
Total 46 18 25 89
Percentage 51.68% 20.22% 28.09% 100%
Table 10: Summary of Intersafe geometric design items covered in the Tunisian guidelines for single carriageway roads
3.2.2.2 Dual carriageway roads
The same assessment as for single carriageway roads was also carried out for the design guidelines relevant for dual carriageway roads. This revealed a similar result.
It is also similar to a study of geometric design guidelines from the Netherlands, which revealed that in the Netherlands, 88% of the items covered in the Intersafe methodology had been described in Dutch guidelines for national motorways (Rijkswaterstaat, 2007; G. Schermers et al., 2013)
24
Primary design element
Mentioned in Tunisian guidelines Not mentioned
in Tunisian guidelines
Total Without road safety effect
With road safety effect
Supporting criteria 18 2 8 28
Alignment 20 0 1 21
Cross-section 19 1 5 25
Intersections 13 0 11 24
Total 70 3 25 98
Percentage 71.43% 3.06% 25.51% 100%
Table 11: Summary of Intersafe geometric design items covered in the Tunisian guidelines for dual carriageway roads
25
4 Prioritising the challenges for safe vehicle and road design standards in Tunisia
4.1 Vehicle design standards Tunisia has a well-defined Road Act and an appropriately defined institutional structure which empowers the public agency ATTT to take care of the management and enforcement of criteria for vehicles during their lifetime.
The legal framework is relatively complete, and even includes the requirements for transformations and vehicles using gas, both LPG and CNG.
The main drivers to improve the system correspond to the three levels considered by the SaferAfrica project: Institutional, organisational and operational. Any detailed conclusion requires to undertake the diagnosis approach described later on in this document.
4.1.1 Institutional level
Evidence shows that the institutional level is well defined in Tunisia thanks to the activities of the ATTT. ATTT works in the field of new vehicles, used vehicles entering into the country, in-use vehicles and transformations.
Furthermore, all motorised road vehicles and their trailers are within the scope of its activities.
4.1.2 Organisational level
Tunisia and ATTT have a long tradition of managing and enforcing fleet requirements. That makes them a reference and benchmark for other countries. Further research is required to identify the precise scope of the requirements for vehicles entering the country and periodic inspection criteria.
4.1.3 Operational level
The extensive experience of Tunisia in vehicles’ compliance puts the country in a privileged position compared to other countries in Africa. The identification of improvements at the operational level requires a more in-depth investigation, as outlined later on in section 6 of this document.
4.2 Road design standards
In Chapter 3, the Tunisian road design practices were assessed using the design items adopted in the Intersafe project (ERSF, 1996) which, although somewhat dated, still provides a very comprehensive reference framework. The assessment was conducted on two levels which intend to reveal the status quo of road design practices in Tunisia, and more specifically to what extent road safety is integrated into that philosophy. In the first place, the assessment focussed on the perceived importance and relevance of the various design aspects covered by Intersafe for the Tunisian situation, and in the second, on the extent to which these items were described in current geometric design guidelines. The first level assessment was done using effect, relevance and researchability as criteria, whereas the second level used inclusion in the guidelines and the relationship with safety as parameters for describing the situation.
In this chapter, the result of the assessment is combined by applying a scoring for each item and then calculating a total per assessment by multiplying the various dimension scores (see Appendix A and B). This first dimension (perceived relevance for guidelines) scored a maximum of 27 points, whereas the second dimension (degree of inclusion in Tunisian guidelines) scored a maximum of 12. A total score based on a weighted average of the two dimensions produced a total score per design item and a total for each of the four primary design elements (supporting criteria; alignment; cross-section and intersections/interchanges). For this project it was decided to select the three highest scoring elements in each one of the primary design element categories. It is also possible to produce a
26
prioritisation based on all items irrespective of the primary category they fall in. However, the results in Chapter 3 made clear that many Intersafe items are deemed important for the Tunisian situation whilst many of these are not included in the guidelines, and if they are, the relationship with road safety is not adequately addressed. The adopted scoring and prioritisation process were designed to ensure that exactly those design items/elements that are perceived relevant, have not been included or are badly described, score high on the priority lists.
4.2.1 Prioritising road design elements for guidelines for single carriageway rural roads in Tunisia.
Table 12 shows the top three scoring items per primary design element, which, according to the assessment, require inclusion, amendment or updating in current Tunisian design guidelines. In the section dealing with the supporting or basic criteria of the design guidelines there is a high perceived need to better describe the aspects dealing with the relationship between safety and design vehicle characteristics and friction coefficient (longitudinal and side) (Table 12).
In terms of alignment, stop areas for brake checking were rated as having the highest priority to be revised in current guidelines. For cross-sectional elements, the aspect dealing with surfacing was deemed the single most important for reviewing in current guidelines. In the final section, dealing with design elements for intersections, traffic safety records and local speed limits were deemed as being the most important items that needed revisions in current guidelines for single carriageway roads.
Primary design
Element Design item Weighted score Ranking
Supporting criteria Design vehicle characteristics 100,00 1
Longitudinal friction coefficient 83.33 2
Side friction coefficient 83.33 2
Deceleration 83.33 2
Safety distances 83.33 2
Overhead and lateral clearances 75,00 3
Alignment Stop areas for brake checking 83.33 1
Warrants and spacing 72.22 2
Type and length 72.22 2
Radii not recommended 58.33 3
Super elevation 58.33 3
Cross-section Surfacing 83.33 1
Crossfall 72.22 2
Tunnels 64.81 3
Intersections Traffic safety records for intersection types
83.33 1
Local speed limits 83.33 1
Number of arms 72.22 2
27
Primary design Element
Design item Weighted score Ranking
Bicycle facilities 72.22 2
Traffic signals 72.22 2
Traffic conflict countermeasures for vulnerable road users
64.81 3
Shape and layout (refer to whether it is a traditional t or X or some deviation)
64.81 3
Table 12: Priority road design aspects requiring attention in Tunisian guidelines for single carriageway roads
4.2.2 Prioritising road design elements for guidelines for dual carriageway rural roads in Tunisia.
Following the same procedure as with single carriageway roads, the three design items with the highest overall score in each primary design element category were selected as those needing urgent revision in current Tunisian geometric design guidelines. In this case, the highest scoring items are listed below.
Primary design Element Design item Weighted score Ranking
Supporting criteria Design vehicle characteristics 100,00 1
Longitudinal friction coefficient 83.33 2
Side friction coefficient 83.33 2
Crossing sight distance 83.33 2
Safety distances 83.33 2
Overtaking sight distance 66.67 3
Abort overtaking sight distance 66.67 3
Alignment Radii not recommended 58.33 1
Super elevation 58.33 1
Minimum radius 58.33 1
Curve following a straight section 58.33 1
Compatibility of two successive curves 58.33 1
Convex curves 58.33 1
Warrants and spacing 58.33 1
Internal defects of a bend 55.56 2
Straight sections and large radius curves 47.22 3
Transition curves 47.22 3
Design consistency 47.22 3
Gradient 47.22 3
28
Primary design Element Design item Weighted score Ranking
Auxiliary (climbing or passing) lane suppression: type and length of drop
47.22 3
Improvement of existing roads 47.22 3
Type and length 47.22 3
Coordination of horizontal and vertical alignments
47.22 3
Cross-section Surfacing 83.33 1
Road markings 83.33 1
Tunnels 72.22 2
Lane width vs. design speed 64.81 3
Intersections Maximum absolute value for the grade of the freeway through the interchange area
83.33 1
Minimum value for horizontal curvature throughout the interchange area
83.33 1
Turning radii for design vehicle 83.33 1
Length of access control along the crossroad beyond the interchange, to ensure its integrity
72.22 2
Land development and access management measures are in place for the interchange area (Y or N)
72.22 2
Traffic control 72.22 2
Requirements for consistency in exit pattern with other nearby interchanges
64.81 3
Over the freeway 64.81 3
Table 13: Priority road design aspects requiring attention in Tunisian guidelines for dual carriageway roads
29
5 Development of an overall prioritisation strategy and formulation of the most promising improvement opportunities for vehicle and road design standards in Tunisia
5.1 Vehicle design standards The enabling project plan for Tunisia includes mainly two activities: diagnosis and support project. At this point, it is only possible to address the diagnosis section in detail. However, it is very much necessary to take into account the advanced stage of vehicle compliance and fleet enforcement management.
5.1.1 Diagnosis
The Global Road Safety Facility (GRSF) of the World Bank (WB) has started a series of diagnosis projects in some sub-Saharan countries in order to precisely assess the needs regarding the regulatory framework of the process. Projects are called Assessment of Vehicle Inspection Schemes (AVIS), and focus on three main aspects:
Capacity building Entering vehicles, depending on if they are new or used Already existing vehicles
The first report was done on Togo11 and is the result of a detailed work plan that can be reapplied in all other countries.
The precise definition of the project is as follows12:
The Objectives of the AVIS study is to review current practices in vehicle inspection regimes in defined countries, to make context-specific recommendations for each of them. The aim is to improve the way these inspection programs contribute to the countries' overall ability to manage the motorisation process and improve road safety outcomes and other public policy objectives. It also recommends an overall program of capacity building toward implementing the recommendations.
The scope of the assessment shall include two regimes for the country, one covering the inspection of in-use vehicles, and the other covering certification of vehicles entering the registered vehicle fleet for the first time, whether through manufacture or import and a program of capacity building.
Scope A: In-use vehicle inspections
A. The consultant shall: B. Document current practice with respect to in-use vehicle inspections in the country, both as
related to road safety and vehicle emissions C. Identify key vehicle safety practices / aspects that should be incorporated into periodic
technical inspections, where they are not already practiced D. Propose and recommend a plausible structure for carrying out in-use vehicle inspections
going forward, taking into account the need to incorporate not only road safety, but also
11 https://citainsp.org/wp-content/uploads/2018/07/TogoReportFinalEN.Final_.pdf 12 Extract of Term of Reference for GRSF’s AVIS projects
30
pollutant emissions, in the control tests. The recommended structure should take the following into account:
a. Assume that whatever pollution control regime will be adopted, it would likely involve control of PM and non-methane hydrocarbon emissions from gasoline and diesel vehicles in the short run, and would need to include NOx control in the medium to long run, in accordance with the requirements set for new and used vehicles being registered in the country.
b. The current and anticipated future size and age of the vehicle fleet should be taken into account both for the country as a whole and the major metropolitan areas within the country
c. Dimensions and business-case of the inspection operations should be considered and factored into the recommendations, taking into account needed investments, institutional development and strengthening at all levels (national, regional, local), facilities development, data management, communication and awareness campaigns, on-road and administrative enforcement, fraud control and training
Scope B: Certification of vehicles entering the registered vehicle fleet for the first time
Many countries are dependent primarily on vehicle imports to grow their vehicle fleets. Scope B is intended to evaluate and make recommendations on the process by which entering vehicles (that is, vehicles being imported, including locally assembled vehicles based on imported kits) are considered eligible for first-time registration. The consultant shall:
A. Document and describe current practice with respect to import vehicle inspection, as related to structural integrity / crash-worthiness of the vehicle, crash avoidance and mitigation features of the vehicles, and emissions control and performance. Such documentation would include identification and description of the relevant international agreements, if any, to which the country formally adheres or voluntarily submits to.
B. Identify key weaknesses in the current import certification process, with reference to international best practice
C. Propose and recommend one or more plausible scenarios for modifying the vehicle import certification process in line with public policy aims of improving both crash avoidance and crashworthiness characteristics of the vehicle fleet over time, as well as emissions characteristics. The considered scenarios should include considerations of needed investments, institutional capacity to administer the system, institutional strengthening at all levels (national, regional, local, private), facilities development, data management, communication and awareness, fraud control and training.
Scope C: Capacity building
The consultant shall: A. Propose needed national, regional and local training for administrative and technical
nationals via an action plan. This proposal shall consider all different department and levels within the authorities and relevant stakeholders.
The proposed training should be relevant to the anticipate roles of the different stakeholders, and shall include the governmental departments taking care of new and in-use vehicle standards, registration of vehicles, management of vehicle workshops, police, customs and transports.
Regarding the private side, the stakeholders to be considered are individual vehicle owners, drivers, big fleet managers, repair workshops, vehicle importers and manufacturers, parts importers and manufacturers, and inspection services, as relevant.
B. Propose a layout for a standard vehicle inspection station, in terms of equipment, facilities, staffing, as input for the Government
31
C. Propose and conduct study tours in partner countries (industrialized and emerging/developing countries), with the aim of sharing implementation approaches from countries with best practices.
The assignment will be conducted by a team of two individual consultants.
Deliverables
The expected deliverables from the team of individual consultants are as follows: 1. An inception report prepared before the first field visit that will list the main information
collected from the desk review, and identify the issues to clarify during the field visit as listed under the Scope of Work section of the present project description. This note will notably include a review of the current status of the vehicle legal framework of the country, including the requirements for new vehicles, in-use vehicles and used imported vehicles. That shall comprise as well a description of the arrangements that the country authorities have set up to manage the legal framework related to road vehicles. Regulations will be analysed from the perspective of individual use and commercial use whenever the distinction is relevant.
2. A field visit report that will include the clarifications on the issues listed in the inception report, relevant information collected during the field visit, program and contact details for stakeholders met.
3. A proposal of specific and realistic implementable frameworks for road vehicle control, with respect to both in-use vehicles, and vehicles newly entering the fleet for first time registration, taking into account already existing international approaches like the 1997 Vienna Agreement of the UN ECE adapted to the country, including the concepts listed in “Objectives and Scope of the Work” of these Terms of Reference. This could be phased approach, or different solutions depending on the purpose of the vehicle, personal or commercial
4. A template business plan for inspection facilities that will recommend and financially evaluate needed investments inter alia: facilities to conduct used vehicles’ inspections and supplies of needed technical equipment, e-systems to manage data as needed, communication and awareness campaigns, etc.
Timing of the Assessment
This is the forecast of resources allocation for the AVIS assessment:
Activities Scheduled time
1. Preparation of the assessment 5 working days
2. Field work in the country 10 working days
3. Assessment and report writing 5 working days
The two consultants will jointly produce all deliverables. The estimated level of effort is maximum 20 days each.
32
This is the detailed schedule including additional activities to undertake. Dates are related to the signature of the contract:
Week #
1 2 3 4 5 6 7 8 9 10 11
Kick of meeting
Preparation of assessment
Mission
Presentation of mission outcome
Draft report
Final mission report
Required Assessments Resources
The selection of consultants should avoid conflicts of interest with personal or professional affiliations relevant to the assignment.
Consultants to conduct the assessment should be expert with extensive international experience in vehicle inspection and/or road transportation in general.
The consultant's team should be technically sound and not have an implicit or explicit interest in the study's outcomes. The confidence of the clients that they are getting the best technical advice is of paramount importance.
Travel expenses are budgeted for ten days stay in the country.
5.1.2 Support project
The specific support project for Tunisia can only be defined after conducting the AVIS project as outlined above, or a similar kind of project. To provide an indication, the support project undertaken after the diagnosis in Togo involved five consultants for 30 months (not full time).
5.2 Geometric design standards The overall conclusion for road geometric design guidelines in Tunisia is that a thorough revision of the current guidelines is required. The revision should make provision for developing first of all the country’s own guidelines with separate geometric design guidelines for urban roads, rural single carriageway road and dual carriageway roads. However, the assessment has revealed that a revision alone will not be particularly valuable, unless an explicit attempt is made to develop and describe the relationship between design elements and road safety. The concept of the safe systems approach must be firmly entrenched in the philosophy of the guidelines. The prioritisation process has identified several items that have a high relevance for design practices (and therefore guidelines) and that are poorly described in the current guidelines in Tunisia. In chapter 4, the three highest scoring items in
33
each of the main design elements (Basic elements; alignment; cross-section and intersection/interchanges) were selected as priority items. For further developing the guidelines, this chapter proposes detailed investigation and research of the top 10 items across the four main design elements. This serves to illustrate the process which the Tunisian road authorities should adopt in the revision of the guidelines. Such revision may entail desk-top type research based on international literature, detailed local field research to account for unique local conditions (such as the design vehicle; human behaviour, etc.) or simply adopting recognised international standards and values. Of importance, however, is that the revised guidelines be developed considering the specific research questions developed in this process.
5.2.1 Single carriageway rural roads
Table 14 provides an overview of the highest scoring design items from the four primary categories discussed in Chapter 4. This reveals that there are 6 items covered under basic requirements, 1 under alignment, 1 under cross-section and 2 under intersections. Each of these items needs to be elaborated upon during a structural and systematic revision of design guidelines for single carriageway rural roads in Tunisia. There is a clear need to develop and describe the relationship of these design elements with road safety and to make the effects of deviations from the norms clear. This will enable designers to gain insights into the relationships and of the consequences should they wish to deviate from the minimum norms described by the guidelines.
Table 14: Top priority items for investigation and inclusion of geometric design standards for single carriageway roads in Tunisia.
For each of the prioritised design items described in Table 14, research questions were developed which serve as the basis input for the team responsible for reviewing and drafting the new geometric
Design item Element
Weighted scores based on relevance and
degree of inclusion
(%)
Design vehicle characteristics Basic requirements 100.00
Longitudinal friction coefficient Basic requirements 83.33
Side friction coefficient Basic requirements 83.33
Deceleration Basic requirements 83.33
Safety distances Basic requirements 83.33
Stop areas for brake checking Alignment 83.33
Surfacing Cross-section 83.33
Traffic safety records for intersection types Intersections 83.33
Local speed limits Intersections 83.33
Overhead and lateral clearances Basic requirements 75.00
34
design guidelines for single carriageway rural roads in Tunisia. These are shown in Table 15 to Errore. L'origine riferimento non è stata trovata..
Basic criteria
Item 1: Design vehicle characteristics
Priority scoring (max 100)
100
Background The physical dimensions of vehicles, their performance and operational characteristics have a significant impact on the physical space provided and it is essential that these impacts are carefully considered during geometric and operational design.
The dynamic performance of recent vehicles under extreme geometrical conditions is not the same as that of older ones (ESP, EBD ...)
The acceleration and deceleration of heavy goods vehicles is also different from those of light vehicles, especially in case of steep slopes.
Underlying research questions
Which are the widths of lanes suitable to the vehicles in circulation?
What are the effects on safety of static and dynamic characteristics of vehicles?
What are the accepted acceleration and deceleration rates of different vehicle types given both the best and worst type driver? What coefficients of deceleration are relevant for sealed and unsealed roads for different vehicle types?
What are the maximum slopes and ramps that can be used by different types of vehicles?
Table 15: Research item 1: Design vehicle characteristics aspects in design of single carriageway rural roads in Tunisia
Basic criteria
Item 2: Longitudinal friction coefficient
Priority scoring (max 100)
83.3
Background Since vehicle tyres are the only part of a vehicle which remains in constant contact with the road, information about the tyre-road friction is critical to vehicle’s longitudinal, lateral and roll dynamics and control. Longitudinal friction coefficient is the basis for delivering critical parameters of road design, such as stopping distance, but also determines the speed limits on curves.
Underlying research questions
How can longitudinal friction coefficient measurements be incorporated into the road design guidelines?
What are the safety consequences related to side friction coefficients?
What are time effects?
What kind of pavements should be included in assessing side friction coefficient?
What about gravel/dirt roads?
To what extent will the longitudinal friction coefficient impact be stopping sight distance?
Table 16: Research item 2: Longitudinal friction coefficient on two-lane rural roads in Tunisia
35
Basic criteria
Item 3: Side friction coefficient
Priority scoring (max 100)
83.3
Background Since vehicle tyres are the only part of a vehicle which remains in constant contact with the road, information about the tyre-road friction is critical to vehicle’s longitudinal, lateral and roll dynamics and control. Side friction coefficient is the basis for delivering critical parameters of road design, such as the speed limits on curves and course correction in case of accidental exit.
Underlying research questions
How can the side friction coefficient measurements be incorporated into the road design guidelines?
What are the safety consequences related to longitudinal friction coefficients?
What kind of pavements should be included in assessing longitudinal friction coefficient?
What about gravel/dirt roads?
What impact does the side friction coefficient have on shoulder widths?
Table 17: Research item 3: Side friction coefficient on two-lane rural roads in Tunisia
Basic criteria
Item 4: Deceleration Priority scoring (max 100)
83.3
Background The physical dimensions of vehicles, their performance and operational characteristics have a significant impact on the physical space provided and it is essential that these impacts are carefully considered during geometric and operational design.
The dynamic performance of recent vehicles under extreme geometrical conditions is not the same as that of older ones (ESP, EBD)
The acceleration and deceleration of heavy goods vehicles is also different from those of light vehicles, especially in case of steep slopes.
Underlying research questions
What are the accepted acceleration and deceleration rates of different vehicle types given both the best and worst type driver?
What coefficients of deceleration are relevant for sealed and unsealed roads for different vehicle types?
What is the relationship between SSD, deceleration rate and safety?
What is the relationship between deceleration rates and road safety given different vehicle, driver and road surface types?
Table 18: Research item 4: Deceleration aspects in design of single carriageway rural roads in Tunisia
36
Basic criteria
Item 5: Safety distance Priority scoring (max 100)
83.3
Background Safety distance is intrinsically linked to stopping distance which is the result of the reaction time distance and the braking distance. It is dependent on the reaction time of the driver, the braking ability of the vehicle and the coefficient of friction between the tyres and the road surface. It is an integral input in the determination of stopping sight distances (SSD) and the underlying parameters for coefficients of friction, driver reaction and perception times etc. are vital in its determination.
Underlying research questions
What are parameter values for driver perception and reaction times, vehicle braking capabilities and deceleration rates and road friction coefficients in establishing stopping (sight) distance?
What is the relationship between different parameter values and road safety?
How does the quality of pavement and especially how do dirt roads impact safety distances?
Are the parameter values established by international studies such as EU Sight (Hogema, Stuiver, Kroon, Broeren, & Barrell, 2015; Weber; et al., 2016) relevant for Tunisian road design guidelines?
Table 199: Research item 5: Stopping distance requirements in the design of single carriageway rural roads
Alignment Item 6: Stop areas for brake
checking Priority scoring (max 100)
83.3
Background Traffic in difficult locations requires the use of brakes more often. This use may lead to a reduction in their efficiency, which is due to heating or wear.
Prolonged or repeated braking, especially when they occur at high speed while developing high energies, have the effect of dangerously heating up brake linings and drums.
This phenomenon is even more recurrent for heavy goods vehicles.
Hence the need to provide stopping areas for brake checks. The choice of their location depends on several parameters, including the characteristics of the brakes, sight distance and the dimensions of vehicles.
Underlying research questions
What is the relationship between brake performance drop, slope and speed?
How to integrate the level of traffic into the sizing of the areas for brake checking?
Are there any statistical studies on the various global parameters (length, average slope, elevation gain, total traffic, heavy goods vehicle traffic) to determine the variable whose correlation is the best with the importance of the incidents?
Table 20: Research item 6: Stop areas for brake checking in design of single carriageway rural roads in Tunisia
37
Cross-section
Item 7: Surfacing Priority scoring (max 100)
83.3
Background The surfacing is a vital element in road safety. It is the first parameter that determines the friction coefficient.
Its behaviour and evolution over time must provide a minimum level of service for users.
Underlying research questions
How t0 determine the type of surfacing?
How does traffic influence the choice of surfacing?
What are the accepted degradation thresholds?
Table 21: Research item 7: Surfacing in design of single carriageway rural roads in Tunisia
Intersections Item 8: Traffic safety
records for intersection types
Priority scoring (max 100)
83.3
Background The recording of road safety data is important and has a significant contribution to improving road safety of road design guidelines. These recordings are even more important in singular points, especially intersections.
Underlying research questions
What are the traffic and safety performance characteristics of the different intersection types?
What are the positive and negative safety consequences for all road users related to the intersection types?
Table 22: Research item 8: Traffic safety records for intersection types on rural two-lane roads in Tunisia
Intersections Item 9: Local speed limits Priority scoring (max 100)
83.3
Background Crossroads, whatever their type, are singular points and require a particular and detailed analysis. In addition to the sight distance that must be ensured, the speed at the approach of the intersections must be punctually adapted (reduced) according to the type of the intersection, the level of the traffic and the predominant movements.
Underlying research questions
What is the visibility distance when approaching the junction?
What are the positive and negative safety consequences for all road users related to the intersection types?
Table 23: Research item 9: Local speed limits on rural two-lane roads in Tunisia
38
Basic criteria
Items 10: Overhead and lateral clearances
Priority scoring (max 100)
75,0
Background Overhead and lateral clearances are essential in the design of underpasses, bridges and other structures over or under roads. Guidelines need to be regularly updated to ensure that the design vehicles adopted represent the actual population of vehicle using roads. Furthermore, these provisions must provide a minimum and acceptable level of comfort and not negatively affect roadway capacity by introducing uncertainty among drivers of vehicles. Specific attention needs to be provided to remedial treatments of sub-standard structures. Also, the provision of these distances should be in accordance to speed.
Underlying research questions
Are data available to derive representative design vehicle templates for road design in Tunisia?
Are international design vehicles appropriate for determining applicable values vertical and lateral clearances in Tunisian guidelines?
Table 24: Research items 10: Lateral and overhead clearances on rural roads in Tunisia.
5.2.2 Dual carriageway roads
The assessment of Tunisian geometric design guidelines for dual carriageway rural roads (see Section 4.1 and 4.2.2) reveal a number of items that were inadequately dealt with in current guidelines and which were deemed important and relevant to include in future guidelines. As mentioned and recommended, new geometric guidelines for rural dual carriageway roads should be developed and these should include the design items described by the assessment in this report. From a road safety perspective, it is important that a direct link be made between the design elements and the safety consequences and effects and that the guidelines adopt a safe systems philosophy (prevent crashes and minimise crash severity).
Table 25 presents the most critical in term of scoring design items for dual carriageway roads that need to be included in the new guidelines, and where additional research is necessary to substantiate the relationship between the design element and road safety.
Many of these items relate to Basic requirements which leads to suggest that road safety in these sections is poorly incorporated and the importance of safety in the design process undermined. Several of the prioritised items for dual carriageways are the same as for single carriageway roads (See 5.2.1) and that is not surprising as many of these are fundamental for geometric design and for road safety and common to both road types.
39
Table 25: Top priority items for investigation and inclusion of geometric design standards for dual carriageway roads in Tunisia.
Similar to 5.2.1 (Single carriageway rural roads), the prioritised design items for dual carriageway roads (
Table 25) were further developed into research themes (Errore. L'origine riferimento non è stata trovata. - Errore. L'origine riferimento non è stata trovata.). For each item a short description of the relationship of the item and design is provided and based on the scoring, a number of underlying research questions were developed. The revision of the Tunisian road design guidelines should explicitly take these questions into account and ensure that the road safety consequences of design choices are described in the guidelines.
Design item Element
Weighted scores based on relevance
and degree of inclusion (%)
Design vehicle characteristics Basic requirements 100.00
Longitudinal friction coefficient Basic requirements 83.33
Side friction coefficient Basic requirements 83.33
Crossing sight distance Basic requirements 83.33
Safety distances Basic requirements 83.33
Surfacing Cross-section 83.33
Road markings Cross-section 83.33
Maximum absolute value for the grade of the freeway through the interchange area
Intersection 83.33
Minimum value for horizontal curvature throughout the interchange area Intersection 83.33
Turning radii for design vehicle Intersection 83.33
40
Basic criteria
Item 1: Design vehicle characteristics
Priority scoring (max 100)
100
Background The physical dimensions of vehicles, their performance and operational characteristics have a significant impact on the physical space provided and it is essential that these impacts are carefully considered during geometric and operational design.
The dynamic performance of recent vehicles under extreme geometrical conditions is not the same as that of older ones (ESP, EBD ...)
The acceleration and deceleration of heavy goods vehicles is also different from those of light vehicles, especially in case of steep slopes.
Underlying research questions
Which are the widths of lanes suitable to the vehicles in circulation?
What are the effects on safety of static and dynamic characteristics of vehicles?
What are the accepted acceleration and deceleration rates of different vehicle types given both the best and worst type driver? What coefficients of deceleration are relevant for sealed and unsealed roads for different vehicle types?
What are the maximum slopes and ramps that can be used by different types of vehicles?
Table 26: Research item 1: Design vehicle characteristics on dual carriageway roads in Tunisia
Basic criteria
Item 2: Longitudinal friction coefficient
Priority scoring (max 100)
83.3
Background Since vehicle tyres are the only part that vehicle body that are in contact with the road, information about the tyre-road friction is critical to vehicle’s longitudinal, lateral and roll dynamics and control. Longitudinal friction coefficient is the basis for delivering critical parameters of road design, such as stopping distance, but also determines the speed limits on curves.
Underlying research questions
How can longitudinal friction coefficient measurements be incorporated into the road design guidelines?
What kind of pavements should be included in assessing longitudinal friction coefficients?
To what extent will the longitudinal friction coefficient impact be stopping sight distance?
Table 27: Research item 2: Longitudinal friction coefficient on dual carriageway roads in Tunisia
41
Basic criteria
Item 3: Side friction coefficient
Priority scoring (max 100)
83.3
Background Since vehicle tyres are the only part of a vehicle which remains in constant contact with the road, information about the tyre-road friction is critical to vehicle’s longitudinal, lateral and roll dynamics and control. Side friction coefficient is the basis for delivering critical parameters of road design, such as the speed limits on curves and course correction in case of accidental exit.
Underlying research questions
How can Side friction coefficient measurements be incorporated into the road design guidelines?
What are the safety consequences related to longitudinal friction coefficients?
What kind of pavements should be included in assessing longitudinal friction coefficient?
What impact does the side friction coefficient have on shoulder widths?
Table 26: Research item 3: Side friction coefficient on dual carriageway roads in Tunisia
Basic criteria
Items 4: Crossing sight distance
Priority scoring (max 100)
83.3
Background A large proportion of crashes occur at junctions and the severity of these is generally higher at intersection in rural areas, primarily due to higher speeds that procure dual roads
The design of the intersections must be clear of any obstructions, whatever their nature, which may affect the sight distance.
Underlying research questions
Horizontal and vertical elements of the route approaching the intersection allow sufficient sight distance?
Land use (construction, dense plantation) does not obstruct visibility at the crossroads?
Table 27: Research items 4, 5: Defining safety distances and vertical - lateral clearances on dual carriageway roads in Tunisia
42
Basic criteria
Item 5: Safety distance Priority scoring (max 100)
83.3
Background Safety distance is intrinsically linked to stopping distance which is the result of the reaction time distance and the braking distance. It is dependent on the reaction time of the driver, the braking ability of the vehicle and the coefficient of friction between the tyres and the road surface. It is an integral input in the determination of stopping sight distances (SSD) and the underlying parameters for coefficients of friction, driver reaction and perception times etc. are vital in its determination.
Underlying research questions
What are parameter values for driver perception and reaction times, vehicle braking capabilities and deceleration rates and road friction coefficients in establishing stopping (sight) distance?
What is the relationship between different parameter values and road safety?
How does the quality of pavement and especially how do dirt roads impact safety distances?
Are the parameter values established by international studies such as EU Sight (Hogema, Stuiver, Kroon, Broeren, & Barrell, 2015; Weber; et al., 2016) relevant for Tunisian road design guidelines?
Table 28: Research item 5: Safety distance on dual carriageway roads in Tunisia
Cross-section
Item 6: Surfacing Priority scoring (max 100)
83.3
Background The surfacing is a vital element in road safety. It is the first parameter that determines the friction coefficient.
Its behaviour and evolution over time must provide a minimum level of service for users.
Underlying research questions
How to determine the type of surfacing?
How does traffic influence the choice of surfacing?
What are the accepted degradation thresholds?
Table 29: Research item 6: Surfacing on dual carriageway roads in Tunisia
43
Cross-section
Item 7: Road markings Priority scoring (max 100)
83.3
Background Road markings have a significant role in guiding vehicles. Especially on intersection – interchange areas. In such areas, without adequate road markings indicating the presence of a lane drop to drivers, erratic manoeuvres might occur. In the case of merging, such manoeuvres can be extremely hazardous. During overtaking also, the presence of road markings is vital.
Underlying research questions
How does local climate affect road markings?
To what extent do road markings impact pavement friction?
What are the safety benefits of road markings and the consequences of poor maintenance on safety?
How can road markings be made to last longer?
How can road markings be visible during night driving?
Table 30: Research item 7: Road markings on dual carriageway roads in Tunisia
Intersection
Item 8 & 9: Maximum absolute value for the grade
of the freeway / Minimum value for horizontal
curvature throughout the interchange area
Priority scoring (max 100)
83.3
Background The risk of accidents in the interchange areas is greater than in the straight section because it is a manoeuvring area and users must make decisions on routes.
Therefore, geometric conditions must facilitate manoeuvres while offering better visibility.
Underlying research questions
What characteristics of vehicles are adopted for determining the values?
What type of locations are appropriate?
How does sight distance affect these parameters?
Table 31: Research item 8 & 9: Maximum absolute value for the grade of the freeway /Minimum value for horizontal curvature throughout the interchange area on dual carriageway roads in Tunisia
44
Intersection Item 10: Turning radii for
design vehicle Priority scoring (max 100)
83.3
Background Guidelines need to be regularly updated to ensure that the design vehicles adopted represent the actual population of vehicle using roads. Furthermore, these provisions must provide a minimum and acceptable level of comfort and not negatively affect roadway capacity by introducing uncertainty among drivers of vehicles. Special attention needs to be paid to remedial treatments of sub-standard structures.
Underlying research questions
Are data available to derive representative design vehicle templates for road design in Tunisia?
Are international design vehicles appropriate for determining applicable values for turning radii in Tunisian guidelines?
Assess current structures on dual carriageway roads in Tunisia and establish compliance with norms for turning radii?
Table 32: Research item 10: Turning radii for design vehicle on dual carriageway roads in Tunisia
45
6 Recommendations for improvement projects/practices in Tunisia
6.1 Road design standards
The assessment of the geometric design guidelines for single and dual carriageway roads in Tunisia revealed that the guidelines are dated and in need of updating. The assessment revealed that road safety in general, and the safe systems thinking in particular, have not been systematically integrated into the design guidelines or procedures described in them. Consequently, road designers cannot reliably estimate the road safety consequences of design choices and there is need to make these explicit in the guidelines.
It is recommended that the geometric design guidelines for roads in Tunisia be systematically reviewed and revised with the aim of incorporating safe systems thinking into design practices. The assessment revealed that most design aspects covered by the four primary design categories in the Intersafe procedures were not adequately covered in the Tunisian guidelines. The prioritisation process, in which the relevance of each design aspect was assessed in conjunction with the degree to which the specific aspect was dealt with in current guidelines, revealed that in terms of basic requirements, there is a need to revise the items dealing with vehicle acceleration/deceleration criteria, sight distances, stopping distances, lateral clearances and the approach to speed limits.
Chapters dealing with alignment need to be revised with respect to items dealing with vehicle design, friction coefficient, curves, gradients and design consistency. The chapters dealing with cross-section need revision with respect to warrants and spacing, radius and road markings. Chapters dealing with intersections need revision with respect to sight distances, safety records and design speeds.
Based on these results, it is recommended that the entire guidelines be systematically revised and that the link with road safety impacts is systematically included to ensure that the consequences of design choices can be established during the design process. Furthermore, it is essential that the concept of the safe systems approach be entrenched in the guidelines to ensure that the philosophy is to prevent crashes from occurring (safety by design) and where these cannot be prevented, the consequences are limited (forgiving design).
The revision should make provision for developing first of all the country’s own guidelines. Furthermore, it is recommended that separate geometric guidelines be prepared for single carriageway rural roads and for dual carriageway rural roads. Although urban roads have not been dealt with in this report, it is advisable to develop specific road design and road safety standards for urban roads as well.
A revision of the standards and guidelines as suggested above could be financed through (for example) the UN Road Safety Trust Fund, provided such project proposals are submitted by the government itself via and with the support of one of the accredited agencies and with the support or organisations/stakeholders with relevant international and regional experience. It is advisable to couple such proposals with other initiatives, such as twinning projects, and other initiatives within the SaferAfrica project.
To ensure that road designs comply with the most recent safety standards, it is also recommended that road safety audit and inspection procedures are not only formalised for all new road construction projects in Tunisia but also systematically implemented. These audits and inspections must be mandatory, and the recommendations of these safety procedures must be formally adopted in the design process. To ensure that audit and inspection findings are incorporated in revised designs, the procedures must be given a binding status. In that way, design teams and developers cannot ignore or neglect to seriously consider changes aimed at eliminating design constraints and potential failures. Arguments to not adapt potential safety defects in the design process will be the exception.
It is recognised that capacity in road safety in general, and road safety auditing in particular, may be a serious constraint in the Tunisian situation. However, there are capacity building programmes
46
available within SaferAfrica (WP6) as there are specific courses - aimed at training road safety auditors – available in several countries. The Tunisian road authorities should pursue a programme to develop the necessary strategies for implementing and formalising road safety audits, whilst simultaneously developing action plans to develop and train the required resources to support the implementation thereof.
6.2 Recommendations for improvement of vehicle standards Precise recommendations for the improvement of the standards for vehicles will be possible once the assessment activity described in item 5.1 of this document has been completed. Nevertheless, it seems possible to foresee that one of the first issue to tackle will be to develop the detailed definition of some of the standards, including the evaluation to the practical adherence to UN Regulations.
47
7 References African Development Bank, 2001, « Rapport d’évaluation: Projet d’aménagement du réseau routier classé- Phase 3- République Tunisienne» ; BAF ; 67
African Development Bank. (2014a). Road Safety Manual for Africa: New roads and schemes-Road safety Audit.
African Development Bank. (2014b). Road Safety Manuals for Africa, Existing roads-Pro-active approaches.
African Development Bank. (2014c). Road Safety Manuals for Africa: Existing roads-reactive approaches.
ARP- Aménagement des Routes Principales, the French guidelines for the design of interurban trunk roads https://www.scribd.com/doc/220912955/amenagement-des-routes-principales-ARP-pdf
Carnis L., Yerpez J., Bouhamed N. (2018), Road Safety Management Capacity Review – Tunisia, SaferAfrica WP 5 Report, D5.3
ERSF. (1996). INTERSAFE : technical guide on road safety for interurban roads. Brussels.
ICTAVRU - Instruction sur les Conditions Techniques d’Aménagement des Voies Rapides Urbaines, the French guidelines for designing high speed urban roads and motorways.
ICTAAL- Instruction sur les Conditions Techniques d’Aménagement des Autoroutes de Liaison, the French guidelines for designing interurban motorways http://dtrf.setra.fr/pdf/pj/Dtrf/0002/Dtrf-0002540/DT2540.pdf
Khalifi, A,. Subit, D. (2017): Vehicle Type-Approval and Road Worthiness Test in Togo. WB, GRSF and CITA
Lamm, R., Psarianos, B., Mailaendar, T. (1999). Highway design and traffic safety engineering handbook. McGraw-Hill, New York.
MEFF (Ministère de l’économie et des finances français), 2015, « Le secteur des transports en Tunisie », Direction générale du Trésor, 3p PAU : Urban Development Plan.
Schermers, G., Dijkstra, A., Mesken, J., & Baan, D. d. R. H. (2013). Richtlijnen voor wegontwerp tegen het licht gehouden.
Schermers, G., Mavromatis, S., Fernández, E. (2019). Assessment of standards for road design and vehicle safety in Kenya: Proposed amendments and enabling project plans. SaferAfrica WP5 report, deliverable D5.20.
SETRA. (1998). Aménagement des Carrefours Interurbains sur les routes principales – Carrefours plans - Guide Technique.
SETRA. (2006). Comprendre Les Principaux Paramètres De Conception Géométrique Des Routes. 29. Retrieved from http://www.infra-transports-materiaux.cerema.fr/IMG/pdf/conception_geometrique_route.pdf
SETRA, & LCPC. (1994). Conception et dimensionnement des structures de chaussée — guide technique. Guide Technique, Dec. Retrieved from http://scholar.google.com/scholar?hl=en&btnG=Search&q=intitle:Conception+et+dimensionnement+des+structures+de+chaussées#1
Souleimen Ouannes M, 2016, « La sécurité routière en Tunisie, comprendre les problèmes pour mieux agir ». C·A·Perspectives on Tunisia No. 04-2016, Center for Applied Policy Research 8p.
48
Usami, D.S., Wounba, J.F., Nkeng, G.E., Zammataro, S., Fernández, E. (2019). Studies on the standardisation of vehicles and road infrastructure – Cameroon Report. SaferAfrica WP 5 report, deliverable D5.17.
49
8 Appendixes
8.1 SaferAfrica assessment of the relevance for safety of Intersafe design items to Tunisian design guidelines
8.1.1 Interurban single carriageway roads
1
BASIC ASSUMPTIONS A B C D
BASISCRITERIA Relevant to
safety
Relevance covered in literature
(Qualitative/descriptive to numerical:
Researchable in regards to
safety
Final score Priority
D=AxBxC
(small to large: 1-3) (1-3) Very low to very high
1-3)
1.1 General approach
1.1.1 Design speed approach 1 3 1 3
1.1.2 Speed limit approach 2 3 2 12
1.1.3 Actual speed approach 3 3 1 9
1.2 Reaction time 3 2 1 6
1.3 Eye position and object position
1.3.1 Eye height 1 2 2 4
1.3.2 Lateral eye position 2 2 2 8
1.3.3 Object height 3 2 2 12
1.3.4 Lateral object position 3 2 2 12
1.4 Friction coefficient
1.4.1 Longitudinal friction coefficient 3 3 2 18
1.4.2 Side friction coefficient 3 3 2 18
1.5 Vehicle deceleration and acceleration
1.5.1 Deceleration 3 3 2 18
1.5.2 Acceleration 1 2 2 4
1.6 Action distances
1.6.1 Stopping distance 3 3 2 18
1.6.2 Overtaking distance 2 2 2 8
1.7 Sight distance
1.7.1 Stopping sight distance 3 3 2 18
1.7.2 Meeting sight distance 3 3 2 18
1.7.3 Overtaking sight distance 3 3 2 18
1.7.4 Abort overtaking sight distance 2 2 3 12
1.7.5 Crossing sight distance 3 2 1 6
1.8 Design vehicle characteristics 3 3 3 27
1.9 Clearances
1.9.1 Dimensions 3 3 2 18
1.9.2 Swept path 2 3 3 18
1.9.3 Overhead and lateral clearances 3 3 3 27
1.9.4 Safety distances 3 3 2 18
Annex Road lighting 3 3 2 18
50
2 ALIGNMENT A B C D
ALIGNMENT Relevant to
safety
Relevance covered in literature
(Qualitative/descriptive to numerical:
Researchable in regards to
safety
Final score Priority
D=AxBxC
(small to large:
1-3) (1-3) Very low to very high
1-3) 2.2 Horizontal alignment
2.2.1 Principles 1 1 1 1
2.2.2 Straight sections and large radius curves 1 1 1 1
2.2.3 Curves
2.2.3.1 Radii not recommended 3 3 2 18
2.2.3.2 Super elevation 3 3 2 18
2.2.3.3 Minimum radius 3 3 2 18
2.2.4 Rules for linking alignment elements
2.2.4.1 Curve following a straight section 3 2 2 12
2.2.4.2 Compatibility of two successive curves
3 2 2 12
Compatibiliteit van twee opeenvolgende bogen 0
2.2.4.3 Transition curves
2 3 2 12 Overgangsbogen
2.2.4.4 Internal defects of a bend 3 1 1 3
2.2.4.5 Design consistency 3 2 2 12
2.2.5 Project planning to improve existing roads 3 2 2 12
2.3 Vertical alignment
2.3.1 Gradient 2 3 2 12
2.3.2 Vertical connecting curves
2.3.2.1 Convex curves 3 3 2 18
2.3.2.2 Concave curves 1 3 2 6
2.3.3 Climbing lanes
2.3.3.1 Passing/overtaking lanes (old 3.2.4) 2 2 2 8
2.3.3.2 Auxiliary (climbing or passing) lane suppression: type and length of drop
3 2 2 12
2.3.4 Improvement of existing roads 3 1 1 3
2.3.5 Emergency escape ramps
2.3.5.1 Warrants and spacing 2 3 2 12
2.3.5.2 Type and length 2 3 2 12
2.3.5.3 Stop areas for brake checking 3 2 3 18
2.4 Coordination of horizontal and vertical alignments 2 3 2 12
51
3 CROSS-SECTION A B C D DWARSPROFIEL
Relevant to safety
Relevance covered in literature
(Qualitative/descriptive to numerical:
Researchable in regards to
safety
Final score Priority
D=AxBxC
(small to large:
1-3) (1-3) Very low to very high
1-3) 3.1.3 Integrated design 2 2 2 8
3.2 Main carriageway
3.2.1 Road Width 2 3 2 12
3.2.2 Running lanes
3.2.2.1 Lane width vs design speed 1 3 2 6
3.2.3 Crossfall 2 3 2 12
3.2.4 Hard shoulders
3.2.4.1 Shoulder width suitable for emergency lane 2 1 2 4
3.2.5 Inner shoulder 1 3 2 6
3.2.6 Median separation 1 2 2 4
3.2.7 Turnouts, safety zones 1 1 2 2
3.2.8 Surfacing 3 3 2 18
3.2.9 Road markings 3 2 2 12
3.3 Roadside
3.3.1 Obstacle-free zones 2 3 2 12
3.3.2 Type of Obstacle 3 1 2 6
3.3.3 Soft shoulders 1 3 2 6
3.3.4 Slopes 1 3 3 9
3.3.5 Drainage channels 2 1 2 4
3.4 Secondary lanes
3.4.1 Cycle lane 3 3 2 18
3.4.2 General 2 1 2 4
3.4.3 Pedestrian sidewalk 3 3 2 18
3.4.4 Bus stops bays 3 3 2 18
3.5 Access control
3.5.1 Frontage roads 2 2 2 8
3.6 Tunnels 2 2 2 8
52
4 INTERSECTIONS A B C D KRUISPUNTEN
Relevant to safety
Relevance covered in literature
(Qualitative/descriptive to numerical:
Researchable in regards to
safety
Final score Priority
D=AxBxC
(small to large:
1-3) (1-3) Very low to very high
1-3) 4.1 Intersection types
4.1.1 Number of arms 2 3 2 12
4.1.2 Traffic control mode 3 2 2 12
4.1.3 Traffic conflict countermeasures for motor vehicles 2 2 2 8
4.1.4 Traffic conflict countermeasures for vulnerable road users
2 2 2 8
4.2 Use of design templates 3 3 2 18
4.3 Design principles 3 3 2 18
4.4 Traffic safety records for intersection types 2 3 3 18
4.5 Intersection between a distributor (high level) and a local road
4.5.1 3- and 4-way 2 3 2 12
4.5.2 Priority control mode 3 2 2 12
4.5.3 Minor road channelization 2 2 2 8
4.5.4 Major road left turn lanes 3 3 2 18
4.5.5 Right turn lanes 2 3 2 12
4.5.6 Bicycle and pedestrian facilities 3 3 2 18
4.5.7 Local speed limits 3 3 2 18
4.5.8 Crossing sight distance requirements 2 2 2 8
4.6 Intersection between two distributor (high level) roads
4.6.1 X or Y intersection 2 2 2 8
4.6.2 Roundabout
4.6.2.1 Use 2 2 2 8
4.6.2.2 Shape and layout (refer to whether it is a traditional t or X or some deviation)
2 2 2 8
4.6.2.3 Crossing sight distance requirements 3 3 2 18
4.6.2.4 Bicycle facilities 3 2 2 12
4.6.3 Traffic signals 3 2 2 12
4.6.4 Grade separation 3 1 2 6
53
8.1.2 Interurban dual carriageway motorways
1
BASIC ASSUMPTIONS A B C D
BASISCRITERIA Relevant to
safety
Relevance covered in literature
(Qualitative/descriptive to numerical:
Researchable in regards to
safety
Final score Priority
D=AxBxC
(small to large:
1-3) (1-3) Very low to very high
1-3) 1.1 General approach
1.1.1 Design speed approach 1 3 1 3
1.1.2 Speed limit approach 2 3 2 12
1.1.3 Actual speed approach 3 3 1 9
1.2 Reaction time 3 2 1 6
1.3 Eye position and object position
1.3.1 Eye height 1 2 2 4
1.3.2 Lateral eye position 2 2 2 8
1.3.3 Object height 3 1 2 6
1.3.4 Lateral object position 3 1 2 6
1.4 Friction coefficient
1.4.1 Longitudinal friction coefficient 3 3 2 18
1.4.2 Side friction coefficient 3 3 2 18
1.5 Vehicle deceleration and acceleration
1.5.1 Deceleration 3 3 2 18
1.5.2 Acceleration 2 2 2 8
1.6 Action distances
1.6.1 Stopping distance 3 3 2 18
1.6.2 Overtaking distance 1 1 2 2
1.7 Sight distance
1.7.1 Stopping sight distance 3 3 2 18
1.7.2 Meeting sight distance 1 3 2 6
1.7.3 Overtaking sight distance 1 3 3 9
1.7.4 Abort overtaking sight distance 1 3 3 9
1.7.5 Crossing sight distance 3 3 2 18
1.8 Design vehicle characteristics 3 3 3 27
1.9 Clearances
1.9.1 Dimensions 3 3 2 18
1.9.2 Swept path 2 3 3 18
1.9.3 Overhead and lateral clearances 2 3 2 12
1.9.4 Safety distances 3 3 2 18
1.9.5 Dynamic lateral clearance 3 2 2 12
1.10 Road image (Rhol=2to7*RBol) 3 1 2 6
1.11 Recommendations for mitigating barrier effect impacts. 1 1 1 1
Annex Road lighting 3 1 1 3
54
2
ALIGNMENT A B C D ALIGNEMENT
Relevant to safety
Relevance covered in literature
(Qualitative/descriptive to numerical:
Researchable in regards to
safety
Final score Priority
D=AxBxC
(small to large:
1-3) (1-3) Very low to very high
1-3) 2.2 Horizontal alignment
2.2.1 Principles 2 2 1 4
2.2.2 Straight sections and large radius curves
2 3 2 12
2.2.3 Curves
2.2.3.1 Radii not recommended 3 3 2 18
2.2.3.2 Super elevation 3 3 2 18
2.2.3.3 Minimum radius 3 3 2 18
2.2.4 Rules for linking alignment elements
2.2.4.1 Curve following a straight section 3 3 2 18
2.2.4.2 Compatibility of two successive curves
3 3 2 18
2.2.4.3 Transition curves 2 3 2 12
2.2.4.4 Internal defects of a bend 3 1 1 3
2.2.4.5 Design consistency 3 2 2 12
2.2.5 Project planning to improve existing roads
3 1 1 3
2.3 Vertical alignment
2.3.1 Gradient 2 3 2 12
2.3.2 Vertical connecting curves
2.3.2.1 Convex curves 3 3 2 18
2.3.2.2 Concave curves 1 3 2 6
2.3.3 Climbing lanes
2.3.3.1 Passing/Overtaking lanes (old 3.2.4)
2 2 2 8
2.3.3.2 Auxiliary (climbing or passing) lane suppression: type and length of drop
2 3 2 12
2.3.4 Improvement of existing roads 3 2 2 12
2.3.5 Emergency escape ramps
2.3.5.1 Warrants and spacing 3 3 2 18
2.3.5.2 Type and length 2 3 2 12
2.3.5.3 Stop areas for brake checking 1 2 2 4
2.4 Coordination of horizontal and vertical alignments
2 3 2 12
55
3
CROSS-SECTION A B C D DWARSPROFIEL
Relevant to safety
Relevance covered in literature
(Qualitative/descriptive to numerical:
Researchable in regards to
safety
Final score Priority
D=AxBxC
(small to large: 1-3) (1-3)
Very low to very high
1-3)
3.1.1 Relationship curve radius / superlevation / speed 3 3 2 18
3.1.2 Superelevation (transition type / length)
2 1 2 4
3.1.3 Integrated design 2 2 2 8
3.2 Main carriageway
3.2.1 Road Width 2 3 2 12
3.2.2 Running lanes
3.2.2.1 Lane width vs. design speed 2 2 2 8
3.2.3 Crossfall 3 3 2 18
3.2.4 Hard shoulders
3.2.4.1 Outside shoulder width suitable for emergency lane
3 2 2 12
3.2.5 Inner shoulder 2 1 2 4
3.2.6 Central reservation 3 3 2 18
3.2.7 Median separation 3 2 2 12
3.2.8 Turnouts, safety zones 3 2 2 12
3.2.9 Surfacing 3 3 2 18
3.2.10 Road markings 3 3 2 18
3.3 Roadside
3.3.1 Obstacle-free zones 3 3 2 18
3.3.2 Type of Obstacle 3 1 2 6
3.3.3 Soft shoulders 2 3 2 12
3.3.4 Slopes 1 3 3 9
3.3.5 Drainage channels 2 1 2 4
3.4 Auxiliary lanes (e.g. bus lanes) 3 3 2 18
3.5 Recommended cross-sections 2 1 2 4
3.6 Access control 3 3 2 18
3.7 Tunnels 3 2 2 12
3.8 Secondary lanes
3.8.1 General 1 1 2 2
3.8.2 Frontage roads 2 1 2 4
3.8.3 Rest and service areas 3 2 2 12
56
4 INTERCHANGE A B C D INTERCHANGE
Relevant to safety
Relevance covered in literature
(Qualitative/descriptive to numerical:
Researchable in regards to
safety
Final score Priority
D=AxBxC
(small to large:
1-3) (1-3) Very low to very high
1-3) 4.1 Interchange and Ramp Spacing
4.1.1 Minimum value for spacing distance?
2 3 2 12
4.1.2 Minimum value for distance between successive entrances and exits?
2 3 2 12
4.2 Approach Alignment to Interchange
4.2.1 Maximum absolute value for the grade of the freeway through the interchange area
3 3 2 18
4.2.2 Minimum value for horizontal curvature throughout the interchange area
3 3 2 18
4.2.3 Sight distance requirement in advance of each exit (desirably decision sight distance)
3 3 2 18
4.3 Interchange Configurations
4.3.1
Differentiation between “service interchange” (between motorway and other road) and “system interchange” (between motorways)
4.3.1.1
An appropriate array of interchange configurations and variations must be evaluated in the design study phase
2 1 2 4
4.3.2
Interchange configuration appropriate for the operational needs, fits the topography and potential site conditions and constraints,
4.3.2.1 Requirements for consistency in exit pattern with other nearby interchanges
2 2 2 8
4.3.3 Requirement for completeness of directional traffic movements provision
1 2 2 4
4.3.4 Mandatory installation of all exits and entrances on the right side of the freeway mainline?
3 2 2 12
4.3.5 Provisions for weaving weaving section design?
4.3.5.1 Distance between the physical merge and exit nose?
3 3 2 18
4.3.6 Location of crossroad in the interchange
4.3.6.1 Over the freeway 2 2 2 8
4.3.7 Route Continuity
4.3.7.1 Priority route is the through facility 3 1 3 9
4.4 Ramp Design
4.4.1 Design speed of the ramp ≥50% of the mainline design speed 3 3 2 18
4.4.2 Length for acceleration at entrance ramps
3 3 2 18
4.4.3 Length for deceleration at exit ramps? 3 3 2 18
4.4.4 Balanced number of exit and entrance?
1 1 2 2
4.5 Crossroad Design
57
4 INTERCHANGE A B C D INTERCHANGE
Relevant to safety
Relevance covered in literature
(Qualitative/descriptive to numerical:
Researchable in regards to
safety
Final score Priority
D=AxBxC
(small to large:
1-3) (1-3) Very low to very high
1-3)
4.5.1 Sidewalks and bicyclist facilities provided along the interchange crossroad.
4.5.1.1 Traffic control at the crossings at interchange ramps (Y or N)
1 1 2 2
4.5.2 Length of access control along the crossroad beyond the interchange, to ensure its integrity
2 3 2 12
4.5.3
Land development and access management measures are in place for the interchange area (Y or N)
3 2 2 12
4.5.4 Design criteria for ramp/crossroad intersection
4.5.4.1 Turning radii for design vehicle 3 3 2 18
4.5.4.2 Capacity 3 3 2 18
4.5.4.3 Traffic control 3 2 2 12
4.5.4.4 Channelization 2 2 2 8
4.5.4.5 Intersection sight distance 3 2 2 12
58
8.2 Degree to which Intersafe geometric design items have been covered in Tunisian guidelines
8.2.1 Interurban single carriageway roads items mentioned and rating Rating team:………………………………… Country: TUNISIA Guidelines assessed: ARP
1 BASIC ASSUMPTIONS BASISCRITERIA
In guidelines?
Veiligheidseffect genoemd? Zo ja, hoe groot? Safety effect mentioned?, If so, how big
Wat is aangenomen of gekozen als waarde? What is the assumed/adopted parameter values
Zijn gevolgen voor veiligheid bij afwijking genoemd? Are the effects of deviating from the norm on safety mentioned/described
Aard onderbouwing Describe the nature of the motivation describing the relationship
Source (if relevant)
1.1 General approach
1.1.1 Design speed approach Uitgangspunt ontwerpsnelheid
Yes No 90-110 None 1.1 ARP
1.1.2 Speed limit approach Uitgangspunt snelheidslimiet
Yes No 90-110 None 1.1 ARP
1.1.3 Actual speed approach Uitgangspunt feitelijke snelheid
Yes No V85 Real speed 4.1 ARP
1.2 Reaction time Reactietijd
Yes No 2 S None 4.2 ARP
1.3 Eye position and object position Positie van oog en object
1.3.1 Eye height Ooghoogte
Yes No 1m None 4.2 ARP (P76-77-78)
1.3.2 Lateral eye position Laterale oogpositie
Yes No Variable None 4.2 ARP (P76-77-78)
1.3.3 Object height Objecthoogte
Yes No Variable None 4.2 ARP (P76-77-78)
1.3.4 Lateral object position Laterale objectpositie
Yes No Variable None 4.2 ARP (P76-77-78)
1.4 Friction coefficient Wrijvingscoëfficiënt
1.4.1 Longitudinal friction coefficient Wrijvingscoëfficiënt in lengterichting
No
1.4.2 Side friction coefficient Wrijvingscoëfficiënt in dwarsrichting
No
59
1 BASIC ASSUMPTIONS BASISCRITERIA
In guidelines?
Veiligheidseffect genoemd? Zo ja, hoe groot? Safety effect mentioned?, If so, how big
Wat is aangenomen of gekozen als waarde? What is the assumed/adopted parameter values
Zijn gevolgen voor veiligheid bij afwijking genoemd? Are the effects of deviating from the norm on safety mentioned/described
Aard onderbouwing Describe the nature of the motivation describing the relationship
Source (if relevant)
1.5
Vehicle deceleration and acceleration Vertraging en versnelling van het voertuig
1.5.1 Deceleration vertraging
No
1.5.2 Acceleration Versnelling
No
1.6 Action distances Benodigde minimale afstand
1.6.1 Stopping distance Stopafstand
Yes No da Distance to pass from V85 to 0 4.2 ARP (P77)
1.6.2 Overtaking distance Inhaalafstand
Yes No 500m None 4.2.d ARP
1.7 Sight distance Zichtafstanden
1.7.1 Stopping sight distance Stopzicht
Yes No da Distance to pass from V85 to 0 4.2.b ARP
1.7.2 Meeting sight distance Zichtafstand bolle boog
Yes No 3xV85 None 4.2.a ARP
1.7.3 Overtaking sight distance Inhaalzicht
Yes No 500m None 4.2.d ARP
1.7.4 Abort overtaking sight distance Zicht om inhalen af te breken
No
1.7.5 Crossing sight distance Stopzicht bij kruispunt
Yes No 8xV85 None 4.2.c ARP
1.8 Design vehicle characteristics Ontwerpvoertuigkenmerken
No
1.9 Clearances Verkeersruimte
1.9.1 Dimensions Afmetingen
Yes No 3.5 None 2.2.b ARP
1.9.2 Swept path Baanverbreding
Yes No 2.3 ARP
60
1 BASIC ASSUMPTIONS BASISCRITERIA
In guidelines?
Veiligheidseffect genoemd? Zo ja, hoe groot? Safety effect mentioned?, If so, how big
Wat is aangenomen of gekozen als waarde? What is the assumed/adopted parameter values
Zijn gevolgen voor veiligheid bij afwijking genoemd? Are the effects of deviating from the norm on safety mentioned/described
Aard onderbouwing Describe the nature of the motivation describing the relationship
Source (if relevant)
1.9.3 Overhead and lateral clearances Profiel van vrije ruimte
Yes No 4.3m, 4.5m
4m,7m
None 2.2.c, 2.5.d & 4.2 ARP
1.9.4 Safety distances Objectafstanden
No
Annex Road lighting Openbare verlichting
Yes Yes 8.3 ARP
61
2 ALIGNMENT ALIGNEMENT
In HWO?
In guidelines?
Veiligheidseffect genoemd? Zo ja,
hoe groot? Safety effect
mentioned?, If so, how big
Wat is aangenomen of gekozen als
waarde?
What is the assumed/adopted parameter value
Zijn gevolgen voor veiligheid bij
afwijking genoemd? Are the effects of deviating from the
norm on safety mentioned/described
Aard onderbouwing
Describe the nature of the motivation describing the
relationship
Source
2.2 Horizontal alignment Horizontaal alignement
2.2.1 Principles Principes
Yes No Ch 3 ARP
2.2.2
Straight sections and large radius curves Rechte wegvakken en bogen met grote boogstraal
Yes High speed
3.1 ARP
2.2.3 Curves Bogen
2.2.3.1 Radii not recommended Te vermijden boogstralen
Indirect Variable None 3.1.a ARP
2.2.3.2 Super elevation Verkanting
Yes No Variable None 3.1.d & 3.1.f ARP
2.2.3.3 Minimum radius Minimum boogstraal
Yes Comfort Variable None 3.1.a & Annexe 1
ARP
2.2.4 Rules for linking alignment elements Regels om rechte wegvakken en bogen met elkaar te verbinden
2.2.4.1 Curve following a straight section Boog na een lang recht wegvak
Yes No 6.3.a ARP
2.2.4.2
Compatibility of two successive curves Compatibiliteit van twee opeenvolgende bogen
Yes No
3.1.c ARP
2.2.4.3 Transition curves Overgangsbogen
Yes Variable None 3.1.e ARP
2.2.4.4 Internal defects of a bend Gebreken binnen een boog
No
2.2.4.5 Design consistency
Indirect
2.2.5 Project planning to improve existing roads Aanpak voor verbeteringen
Yes 1.2 ARP
62
2 ALIGNMENT ALIGNEMENT
In HWO?
In guidelines?
Veiligheidseffect genoemd? Zo ja,
hoe groot? Safety effect
mentioned?, If so, how big
Wat is aangenomen of gekozen als
waarde?
What is the assumed/adopted parameter value
Zijn gevolgen voor veiligheid bij
afwijking genoemd? Are the effects of deviating from the
norm on safety mentioned/described
Aard onderbouwing
Describe the nature of the motivation describing the
relationship
Source
2.3 Vertical alignment Verticaal alignement
2.3.1 Gradient Hellingshoek
Yes Dynamic comfort
Signt comfort 5%, 6% & 7%
None 3.2.a ARP
2.3.2 Vertical connecting curves Vorm van verticale boog
2.3.2.1 Convex curves Bolle boog
Yes Dynamic comfort
Signt comfort 1500m,2200m & 3000m
None 3.2.a ARP
2.3.2.2 Concave curves Holle boog
Yes Dynamic comfort
Signt comfort 1500m,3000m & 6000m
None 3.2.a ARP
2.3.3 Climbing lanes Kruipstrook
2.3.3.1 Passing/overtaking lanes (old 3.2.4)
Yes Speed heterogeneity 1.5.d & 6.1.c ARP
2.3.3.2 Auxiliary (climbing or passing) lane suppression: type and length of drop
Yes Speed heterogeneity 2.4.b ARP
2.3.4 Improvement of existing roads Aanpak voor verbeteringen
Yes No 1.2 ARP
2.3.5 Emergency escape ramps
2.3.5.1 Warrants and spacing
No
2.3.5.2 Type and length
No
2.3.5.3 Stop areas for brake checking
No
2.4
Coordination of horizontal and vertical alignments Aaneensluiting van horizontale en verticale elementen
Yes Sight confort Yes
3.3
63
3 CROSS-SECTION DWARSPROFIEL
In HWO?
In guidelines?
Veiligheidseffect genoemd? Zo ja,
hoe groot? Safety effect
mentioned?, If so, how big
Wat is aangenomen of gekozen als
waarde?
What is the assumed/adopted parameter value
Zijn gevolgen voor veiligheid bij
afwijking genoemd? Are the effects of deviating from the
norm on safety mentioned/described
Aard onderbouwing
Describe the nature of the motivation describing the
relationship
Source
3.1.3 Integrated design Geïntegreerd ontwerp van dwarsprofiel en alignement
Yes Ch 2 ARP
3.2 Main carriageway Hoofdrijbaan
3.2.1 Road Width Verhardingsbreedte
Yes No 3.5m None 2.2.b ARP
3.2.2 Running lanes Rijstroken
3.2.2.1 Lane width vs design speed
No
3.2.3 Crossfall Afschot
Yes
3.2.4 Hard shoulders Vluchtstrook
3.2.4.1 Shoulder width suitable for emergency lane
No
3.2.5 Inner shoulder Redresseerstrook
Yes Accidental exit Trajectory correction
0.75m-2m None 2.2.c ARP
3.2.6 Median separation Middenbermscheiding
Yes No None 2.2.d ARP
3.2.7 Turnouts,safety zones Pechhavens
No
3.2.8 Surfacing Verharding
No
3.2.9 Road markings Markering
Indirect
3.3 Roadside Wegberm
3.3.1 Obstacle-free zones Obstakelvrije zone
Yes No 4m,7m, 8.5m None 2.2.c
3.3.2 Type of Obstacle Obstakeltype
Yes No 2.2.c
3.3.3 Soft shoulders Onverharde berm
Yes
64
3 CROSS-SECTION DWARSPROFIEL
In HWO?
In guidelines?
Veiligheidseffect genoemd? Zo ja,
hoe groot? Safety effect
mentioned?, If so, how big
Wat is aangenomen of gekozen als
waarde?
What is the assumed/adopted parameter value
Zijn gevolgen voor veiligheid bij
afwijking genoemd? Are the effects of deviating from the
norm on safety mentioned/described
Aard onderbouwing
Describe the nature of the motivation describing the
relationship
Source
3.1.3 Integrated design Geïntegreerd ontwerp van dwarsprofiel en alignement
Yes Ch 2 ARP
3.3.4 Slopes Talud
Indirect 3.2.4 & 5.2 ARP
3.3.5 Drainage channels
Yes Weathering Stagnation
5.2 ARP
3.4 Secondary lanes Parallelrijbaan/-strook
3.4.1 Cycle lane Fietspad
Yes No 1.5.g ARP
3.4.2 General Algemeen
3.4.3 Pedestrian sidewalk
Yes Protect pedestrians 1.5.h ARP
3.4.4 Bus stops bays
Yes Protect : Pedestrians, drivers
1.5.f ARP
3.5 Access control
3.5.1 Frontage roads
Yes No 1.1.a ARP
3.6 Tunnels
No
65
4 INTERSECTIONS KRUISPUNTEN
In HWO?
In guidelines?
Veiligheidseffect genoemd? Zo ja,
hoe groot? Safety effect
mentioned?, If so, how big
Wat is aangenomen of gekozen als
waarde?
What is the assumed/adopted parameter value
Zijn gevolgen voor veiligheid bij afwijking
genoemd? Are the effects of deviating from the
norm on safety mentioned/described
Aard onderbouwing
Describe the nature of the motivation describing the
relationship
Source
4.1 Intersection types Kruispunttypen
4.1.1 Number of arms Aantal takken
No
4.1.2 Traffic control mode Regelingstype
Yes No 5.1 ARP
4.1.3 Traffic conflict countermeasures for motor vehicles Maatregelen om conflicten te vermijden voor motorvoertuigen
Indirect No 5.3 ARP
4.1.4 Traffic conflict countermeasures for vulnerable road users Idem voor langzaam verkeer
No
4.2 Use of design templates Ontwerpvoorschriften
Yes No 5.3.a ARP
4.3 Design principles Ontwerpprincipes
Yes No Ch 5 ARP
4.4 Traffic safety records for intersection types Ongevallengegevens per kruispunttype
No
4.5 Intersection between a distributor (high level) and a local road Kruispunten GOW-ETW
4.5.1 3- and 4-way Drie- en viertaks
Yes Yes 5.3.d ARP
4.5.2 Priority control mode Voorrangsregeling
Yes Yes 5.3c & 5.3.d ARP
4.5.3 Minor road channelization Rijbaansplitsing op zijweg
Yes Yes 5.3.c ARP
4.5.4 Major road left turn lanes Linksafstroken op hoofdweg
Yes Yes 5.3 ARP
4.5.5 Right turn lanes Rechtsafstroken
Yes Yes 5.3 ARP
66
4 INTERSECTIONS KRUISPUNTEN
In HWO?
In guidelines?
Veiligheidseffect genoemd? Zo ja,
hoe groot? Safety effect
mentioned?, If so, how big
Wat is aangenomen of gekozen als
waarde?
What is the assumed/adopted parameter value
Zijn gevolgen voor veiligheid bij afwijking
genoemd? Are the effects of deviating from the
norm on safety mentioned/described
Aard onderbouwing
Describe the nature of the motivation describing the
relationship
Source
4.1 Intersection types Kruispunttypen
4.1.1 Number of arms Aantal takken
No
4.1.2 Traffic control mode Regelingstype
Yes No 5.1 ARP
4.1.3 Traffic conflict countermeasures for motor vehicles Maatregelen om conflicten te vermijden voor motorvoertuigen
Indirect No 5.3 ARP
4.1.4 Traffic conflict countermeasures for vulnerable road users Idem voor langzaam verkeer
No
4.5.6 Bicycle and pedestrian facilities Voorzieningen voetgangers en fietsers
Indirect No 5.5 ARP
4.5.7 Local speed limits Plaatselijke snelheidslimiet
No
4.5.8 Crossing sight distance requirements Zichtafstanden
Yes No 8xV85 None 4.2.c ARP
4.6 Intersection between two distributor (high level) roads Kruispunten GOW-GOW
4.6.1 X or Y intersection Yes No None 5.2 ARP 4.6.2 Roundabout
Rotondes
4.6.2.1 Use Verwacht gebruik
Yes No None 5.4 ARP
4.6.2.2 Shape and layout (refers to whather it is a traditional t or X or some deviation) Vorm en ontwerp
No
4.6.2.3 Crossing sight distance requirements Zichtdriehoeken
Yes No 8xV85 None 4.2.c ARP
67
4 INTERSECTIONS KRUISPUNTEN
In HWO?
In guidelines?
Veiligheidseffect genoemd? Zo ja,
hoe groot? Safety effect
mentioned?, If so, how big
Wat is aangenomen of gekozen als
waarde?
What is the assumed/adopted parameter value
Zijn gevolgen voor veiligheid bij afwijking
genoemd? Are the effects of deviating from the
norm on safety mentioned/described
Aard onderbouwing
Describe the nature of the motivation describing the
relationship
Source
4.1 Intersection types Kruispunttypen
4.1.1 Number of arms Aantal takken
No
4.1.2 Traffic control mode Regelingstype
Yes No 5.1 ARP
4.1.3 Traffic conflict countermeasures for motor vehicles Maatregelen om conflicten te vermijden voor motorvoertuigen
Indirect No 5.3 ARP
4.1.4 Traffic conflict countermeasures for vulnerable road users Idem voor langzaam verkeer
No
4.6.2.4 Bicycle facilities Fietsvoorzieningen
No
4.6.3 Traffic signals Verkeerslichten
No
4.6.4 Grade separation Ongelijkvloers
Indirect Ref instructions of urban roundabout
None 5.4 ARP
68
8.2.2 interurban dual carriageway motorways: items mentioned and rating
Rating team:………………………………… Country: TUNISIA Guidelines assessed: - ICTAAL - Note d’information SETRA 2008, vitesse V85 - ICTAVRU (Instruction sur les Conditions Techniques d’Aménagement des Voies Rapides Urbaines)
1 BASIC ASSUMPTIONS BASISCRITERIA
In HWO?
In guidelines?
Veiligheidseffect genoemd? Zo ja,
hoe groot? Safety effect
mentioned?, If so, how big
Wat is aangenomen of gekozen als
waarde?
What is the assumed/adopted parameter value
Zijn gevolgen voor veiligheid bij
afwijking genoemd? Are the effects of deviating from the
norm on safety mentioned/described
Aard onderbouwing
Describe the nature of the motivation describing the
relationship
Source
1.1 General approach
1.1.1 Design speed approach Uitgangspunt ontwerpsnelheid
Yes No V85é Real Speed ICTAAL 1.2 Note SETRA 2006
1.1.2 Speed limit approach Uitgangspunt snelheidslimiet
Yes No 130 110
None ICTAAL 1.2 Note SETRA 2006
1.1.3 Actual speed approach Uitgangspunt feitelijke snelheid
Yes No V85 Real Speed ICTAAL 2.1.1
1.2 Reaction time Reactietijd
Yes No 2s None ICTAAL Annexe 1
1.3 Eye position and object position Positie van oog en object
1.3.1 Eye height Ooghoogte
Yes No 1m None ICTAAL 2.1.2
1.3.2 Lateral eye position Laterale oogpositie
Yes No 2m None ICTAAL 2.1.2
1.3.3 Object height Objecthoogte
Yes No 0.60m None ICTAAL 2.1.3
1.3.4 Lateral object position Laterale objectpositie
Yes No 1m 2.50m
None ICTAAL 2.1.3
1.4 Friction coefficient Wrijvingscoëfficiënt
69
1 BASIC ASSUMPTIONS BASISCRITERIA
In HWO?
In guidelines?
Veiligheidseffect genoemd? Zo ja,
hoe groot? Safety effect
mentioned?, If so, how big
Wat is aangenomen of gekozen als
waarde?
What is the assumed/adopted parameter value
Zijn gevolgen voor veiligheid bij
afwijking genoemd? Are the effects of deviating from the
norm on safety mentioned/described
Aard onderbouwing
Describe the nature of the motivation describing the
relationship
Source
1.4.1 Longitudinal friction coefficient Wrijvingscoëfficiënt in lengterichting
No
1.4.2 Side friction coefficient Wrijvingscoëfficiënt in dwarsrichting
No
1.5 Vehicle deceleration and acceleration Vertraging en versnelling van het voertuig
1.5.1 Deceleration vertraging
Yes No (v) 1.5m/s
None ICTAAL 5.2.6 & A.1
1.5.2 Acceleration Versnelling
Yes No 1m/s None ICTAAL 5.2.6
1.6 Action distances Benodigde minimale afstand
1.6.1 Stopping distance Stopafstand
Yes Anticpate occurent event
da None ICTAAL A.1
1.6.2 Overtaking distance Inhaalafstand
No
1.7 Sight distance Zichtafstanden
1.7.1 Stopping sight distance Stopzicht
Yes Anticpate occurent event
dms None ICTAAL A.1
1.7.2 Meeting sight distance Zichtafstand bolle boog
No
1.7.3 Overtaking sight distance Inhaalzicht
No
1.7.4 Abort overtaking sight distance Zicht om inhalen af te breken
No
1.7.5 Crossing sight distance Stopzicht bij kruispunt
No
1.8 Design vehicle characteristics Ontwerpvoertuigkenmerken
No
1.9 Clearances verkeersruimte
1.9.1 Dimensions Afmetingen
Yes No 3.5m None ICTAAL 4.1.1
70
1 BASIC ASSUMPTIONS BASISCRITERIA
In HWO?
In guidelines?
Veiligheidseffect genoemd? Zo ja,
hoe groot? Safety effect
mentioned?, If so, how big
Wat is aangenomen of gekozen als
waarde?
What is the assumed/adopted parameter value
Zijn gevolgen voor veiligheid bij
afwijking genoemd? Are the effects of deviating from the
norm on safety mentioned/described
Aard onderbouwing
Describe the nature of the motivation describing the
relationship
Source
1.9.2 Swept path Baanverbreding
Yes No ICTAAL 1.6.1
1.9.3 Overhead and lateral clearances Profiel van vrije ruimte
Yes No 4.75m None ICTAAL 4.3
1.9.4 Safety distances Objectafstanden
No
1.9.5 Dynamic lateral clearance Profiel van ruimte
Yes No 10 8.5
None ICTAAL 4.1.3
1.10 Road image (Rhol=2to7*RBol) Wegbeeld (Rhol=2tot7*RBol)
Yes No ICTAAL 2.3
1.11 Recommendations for mitigating barrier effect impacts.
Yes No 1m None ICTAAL 4.1.2
Annex Road lighting Openbare verlichting
Yes No ICTAAL 7.1.7
71
2 ALIGNMENT ALIGNEMENT
In HWO?
In guidelines?
Veiligheidseffect genoemd? Zo ja,
hoe groot? Safety effect
mentioned?, If so, how big
Wat is aangenomen of gekozen als
waarde?
What is the assumed/adopted parameter value
Zijn gevolgen voor veiligheid bij
afwijking genoemd? Are the effects of deviating from the
norm on safety mentioned/described
Aard onderbouwing
Describe the nature of the motivation describing the
relationship
Source
2.2 Horizontal alignment Horizontaal alignement
2.2.1 Principles Principes
Yes No None ICTAAL ch 3
2.2.2 Straight sections and large radius curves Rechte wegvakken en bogen met grote boogstraal
Yes No None ICTAAL 3.1.1 & 3.2.2
2.2.3 Curves Bogen
2.2.3.1 Radii not recommended Te vermijden boogstralen
Indirect No None ICTAAL 3.1.1
2.2.3.2 Super elevation Verkanting
Yes No 2.5% None ICTAAL 4.6
2.2.3.3 Minimum radius Minimum boogstraal
Yes No 1 000 600
None ICTAAL 3.1.1
2.2.4 Rules for linking alignment elements Regels om rechte wegvakken en bogen met elkaar te verbinden
2.2.4.1 Curve following a straight section Boog na een lang recht wegvak
Yes No None ICTAAL 3.1.2
2.2.4.2 Compatibility of two successive curves Compatibiliteit van twee opeenvolgende bogen
Yes No None ICTAAL 3.1.2, 5.2.2 & 9.2.1
2.2.4.3 Transition curves Overgangsbogen
Yes No Min (14, R/9) None ICTAAL 3.1.1 & 3.2.2
2.2.4.4 Internal defects of a bend Gebreken binnen een boog
No
2.2.4.5 Design consistency
Yes No None ICTAAL 3.1
2.2.5 Project planning to improve existing roads Aanpak voor verbeteringen
Yes No None ICTAAL 1.6 & 9
72
2 ALIGNMENT ALIGNEMENT
In HWO?
In guidelines?
Veiligheidseffect genoemd? Zo ja,
hoe groot? Safety effect
mentioned?, If so, how big
Wat is aangenomen of gekozen als
waarde?
What is the assumed/adopted parameter value
Zijn gevolgen voor veiligheid bij
afwijking genoemd? Are the effects of deviating from the
norm on safety mentioned/described
Aard onderbouwing
Describe the nature of the motivation describing the
relationship
Source
2.3 Vertical alignment Verticaal alignement
2.3.1 Gradient Hellingshoek
Yes No 5% 6%
None ICTAAL 3.2.1
2.3.2 Vertical connecting curves Vorm van verticale boog
2.3.2.1 Convex curves Bolle boog
Yes No 4 200 3 000
None ICTAAL 3.2.1
2.3.2.2 Concave curves Holle boog
Yes No 12 500 6 000
None ICTAAL 3.2.1
2.3.3 Climbing lanes Kruipstrook
2.3.3.1 Passing/Overtaking lanes (old 3.2.4)
Yes No None ICTAAL 3.2.2
2.3.3.2 Auxiliary (climbing or passing) lane suppression: type and length of drop
Yes No None ICTAAL 4.5.3
2.3.4 Improvement of existing roads Aanpak voor verbeteringen
Yes No None ICTAAL 9
2.3.5 Emergency escape ramps
2.3.5.1 Warrants and spacing
Yes No None ICTAAL 7.1.4
2.3.5.2 Type and length
Yes No None ICTAAL 7.1.4
2.3.5.3 Stop areas for brake checking
Yes No None ICTAAL 7.1.4
2.4 Coordination of horizontal and vertical alignments Aaneensluiting van horizontale en verticale elementen
Yes No None ICTAAL 3.3
73
3 CROSS-SECTION DWARSPROFIEL
In HWO?
In guidelines?
Veiligheidseffect genoemd? Zo ja,
hoe groot? Safety effect
mentioned?, If so, how big
Wat is aangenomen of gekozen als
waarde?
What is the assumed/adopted parameter value
Zijn gevolgen voor veiligheid bij afwijking
genoemd? Are the effects of deviating from the
norm on safety mentioned/described
Aard onderbouwing
Describe the nature of the motivation describing the
relationship
Source
3.1.1 Relationship curve radius / superlevation / speed Relatie boogstraal/afschot/snelheid
Yes No 2.5 % → 7% None ICTAAL 4.6.2 & 4.6.3
3.1.2 Superelevation (transition type / length) Verkanting (overgang/lengte)
Yes No 14 │∆│ None ICTAAL 4.6.2 & 3.1.3 & 4.6.3
3.1.3 Integrated design Geïntegreerd ontwerp van dwarsprofiel en alignement
Yes No None ICTAAL 4.1
3.2 Main carriageway hoofdrijbaan
3.2.1 Road Width Verhardingsbreedte
Yes No 3.5 m None ICTAAL 4.1.1
3.2.2 Running lanes Rijstroken
No
3.2.2.1 Lane width vs. design speed
No
3.2.3 Crossfall Afschot
No
3.2.4 Hard shoulders Vluchtstrook
3.2.4.1 Outside shoulder width suitable for emergency lane
Yes No 2.5 m 3 m
None ICTAAL 4.1.3 (b)
3.2.5 Inner shoulder Redresseerstrook
Yes No 1,00 m None ICTAAL 4.1.2 (a)
3.2.6 Central reservation Middenberm
Yes No None ICTAAL 4.1.12 (b)
3.2.7 Median separation Middenbermscheiding
Yes No None ICTAAL 7.1.1 (a)
3.2.8 Turnouts,safety zones Pechhavens
Yes No None ICTAAL 7.1.4
3.2.9 Surfacing Verharding
No
3.2.10 Road markings Markering
No
74
3 CROSS-SECTION DWARSPROFIEL
In HWO?
In guidelines?
Veiligheidseffect genoemd? Zo ja,
hoe groot? Safety effect
mentioned?, If so, how big
Wat is aangenomen of gekozen als
waarde?
What is the assumed/adopted parameter value
Zijn gevolgen voor veiligheid bij afwijking
genoemd? Are the effects of deviating from the
norm on safety mentioned/described
Aard onderbouwing
Describe the nature of the motivation describing the
relationship
Source
3.3 Roadside Wegberm
3.3.1 Obstacle-free zones Obstakelvrije zone
Yes No 10 m 8.5 m
None ICTAAL 4.1.3
3.3.2 Type of Obstacle Obstakeltype
Yes No None ICTAAL 4.1.3
3.3.3 Soft shoulders Onverharde berm
Yes Yes None ICTAAL 4.1.3
3.3.4 Slopes Talud
Yes No D > 70 % R < 4 m
None ICTAAL 4.1.3
3.3.5 Drainage channels
Yes No CAO, fossé 50cm None ICTAAL 4.1.3
3.4 Auxiliary lanes (e.g. bus lanes) Verharde bermen of rijstroken voor langzaam gemotoriseerd verkeer
Yes No VSVL None ICTAAL 4.4.5
3.5 Recommended cross-sections Aanbevolen dwarsprofielen
Yes No None ICTAAL 4.1
3.6 Access control
Yes No None ICTAAL 5.2 & 7.2.3
3.7 Tunnels
No
3.8 Secondary lanes Parallel rijbaan/strook
3.8.1 General Algemeen
Yes No None ICTAAL ch 7
3.8.2 Frontage roads
No
3.8.3 Rest and service areas
Yes 30 km 60 km
None ICTAAL 7.4
75
4 INTERCHANGE In HWO?
In guidelines?
Veiligheidseffect genoemd? Zo ja,
hoe groot? Safety effect
mentioned?, If so, how big
Wat is aangenomen of gekozen als waarde?
What is the
assumed/adopted parameter value
Zijn gevolgen voor veiligheid bij
afwijking genoemd? Are the effects of deviating from the
norm on safety mentioned/described
Aard onderbouwing
Describe the nature of the motivation describing the
relationship
Source
4.1 Interchange and Ramp Spacing
4.1.1 Minimum value for spacing distance? Yes No 20 km None ICTAAL 1.4 4.1.2 Minimum value for distance between
successive entrances and exits? Yes No > 1200 m
< 750 m None ICTAAL 5.3
4.2 Approach Alignment to Interchange
4.2.1 Maximum absolute value for the grade of the freeway through the interchange area
No
4.2.2 Minimum value for horizontal curvature throughout the interchange area
No
4.2.3 Sight distance requirement in advance of each exit (desirably decision sight distance)
Yes No dms None ICTAAL 2.2.2
4.3 Interchange Configurations
4.3.1 Differenciation between “service interchange” (between motorway and other road) and “system interchange” (between motorways)
Yes No None ICTAAL Ch 5
4.3.1.1 An appropriate array of interchange configurations and variations must be evaluated in the design study phase
Yes No None ICTAAL 5.2
4.3.2 Interchange configuration appropriate for the operational needs, fits the topography and potential site conditions and constraints,
4.3.2.1 Requirements for consistency in exit pattern with other nearby interchanges
No
76
4 INTERCHANGE In HWO?
In guidelines?
Veiligheidseffect genoemd? Zo ja,
hoe groot? Safety effect
mentioned?, If so, how big
Wat is aangenomen of gekozen als waarde?
What is the
assumed/adopted parameter value
Zijn gevolgen voor veiligheid bij
afwijking genoemd? Are the effects of deviating from the
norm on safety mentioned/described
Aard onderbouwing
Describe the nature of the motivation describing the
relationship
Source
4.1 Interchange and Ramp Spacing
4.1.1 Minimum value for spacing distance? Yes No 20 km None ICTAAL 1.4 4.1.2 Minimum value for distance between
successive entrances and exits? Yes No > 1200 m
< 750 m None ICTAAL 5.3
4.2 Approach Alignment to Interchange
4.3.3 Requirement for completeness of directional traffic movements provision
Yes No None ICTAAL 5.2
4.3.4 Manadtory installation of all exits and entrances on the right side of the freeway mainline?
Yes No None ICTAAL 5.1 & 5.2.6
4.3.5 Provisions for weaving weaving section design?
Yes No None ICTAAL 5.3
4.3.5.1 Distance between the physical merge and exit nose?
Yes No 150 m None ICTAAL 5.2.6
4.3.6 Location of crossroad in the interchange
No
4.3.6.1 Over the freeway
No
4.3.7 Route Continuity
4.3.7.1 Priority route is the through facility
Yes No None ICTAAL 5.1
4.4 Ramp Design
4.4.1 Design speed of the ramp ≥50% of the mainline design speed
Yes 60 km/h None ICTAAL Annexe 2
4.4.2 Length for acceleration at entrance ramps
Yes 200 m+ 75 m None ICTAAL 5.2.2
4.4.3 Length for deceleration at exit ramps?
Yes 150 m None ICTAAL 5.2.6
4.4.4 Balanced number of exit and entrance?
No
77
4 INTERCHANGE In HWO?
In guidelines?
Veiligheidseffect genoemd? Zo ja,
hoe groot? Safety effect
mentioned?, If so, how big
Wat is aangenomen of gekozen als waarde?
What is the
assumed/adopted parameter value
Zijn gevolgen voor veiligheid bij
afwijking genoemd? Are the effects of deviating from the
norm on safety mentioned/described
Aard onderbouwing
Describe the nature of the motivation describing the
relationship
Source
4.1 Interchange and Ramp Spacing
4.1.1 Minimum value for spacing distance? Yes No 20 km None ICTAAL 1.4 4.1.2 Minimum value for distance between
successive entrances and exits? Yes No > 1200 m
< 750 m None ICTAAL 5.3
4.2 Approach Alignment to Interchange
4.5 Crossroad Design
4.5.1 Sidewalks and bicyclist facilities provided along the interchange crossroad. (Pedestrians and bicyclists are particularly vulnerable to high speed approach vehicles turning at ramp terminals).
No
4.5.1.1 Traffic control at the crossings at interchange ramps (Y or N)
No
4.5.2 Length of access control along the crossroad beyond the interchange, to ensure its integrity (A minimum of 30m in urban areas and 100m in rural areas is usually insufficient where additional development is likely).
No
4.5.3 Land development and access management measures are in place for the interchange area (Y or N)
No
4.5.4 Design criteria for ramp/crossroad intersection
4.5.4.1 Turning radii for design vehicle
No
4.5.4.2 Capacity
Yes No 1800 UVP None ICTAAL 1.3.3
78
4 INTERCHANGE In HWO?
In guidelines?
Veiligheidseffect genoemd? Zo ja,
hoe groot? Safety effect
mentioned?, If so, how big
Wat is aangenomen of gekozen als waarde?
What is the
assumed/adopted parameter value
Zijn gevolgen voor veiligheid bij
afwijking genoemd? Are the effects of deviating from the
norm on safety mentioned/described
Aard onderbouwing
Describe the nature of the motivation describing the
relationship
Source
4.1 Interchange and Ramp Spacing
4.1.1 Minimum value for spacing distance? Yes No 20 km None ICTAAL 1.4 4.1.2 Minimum value for distance between
successive entrances and exits? Yes No > 1200 m
< 750 m None ICTAAL 5.3
4.2 Approach Alignment to Interchange
4.5.4.3 Traffic control
No
4.5.4.4 Channelization
Yes No None ICTAAL 5.1.2
4.5.4.5 Intersection sight distance
Yes No Visibility rules and layouts ICTAAL 5.2.6
79
8.3 Scoring and prioritising
8.3.1 Single carriageway roads
BASIC ASSUMPTIONS A B C DSafety effect
mentioned?, If so, how big
Are the effects of deviating from the
norm on safety mentioned/described Total score % Weighted
BASISCRITERIARelevant to
safety
Relevance covered in literature
(Qualitative/descriptive to numerical:
Researchable in regards to
safety
Final score Priority
D=AxBxCIn guidelines?
Total exfxg
(small to large: 1-3) (1-3)Very low to very high
Yes=1, No=2 Yes=1; No=2
No=3; Yes, quanlitative=2; Yes, quantitative=3 Score (Max=12)
1-3)
1.8 Design vehicle characteristics 3 3 3 27 2 2 3 12 39 100,00 100,00 1.4.1 Longitudinal friction coefficient 3 3 2 18 2 2 3 12 30 76,92 83,33 1.4.2 Side friction coefficient 3 3 2 18 2 2 3 12 30 76,92 83,33 1.5.1 Deceleration 3 3 2 18 2 2 3 12 30 76,92 83,33 1.9.4 Safety distances 3 3 2 18 2 2 3 12 30 76,92 83,33 1.9.3 Overhead and lateral clearances 3 3 3 27 1 2 3 6 33 84,62 75,00 1.7.4 Abort overtaking sight distance 2 2 3 12 2 2 3 12 24 61,54 72,22 1.6.1 Stopping distance 3 3 2 18 1 2 3 6 24 61,54 58,33 1.7.1 Stopping sight distance 3 3 2 18 1 2 3 6 24 61,54 58,33 1.7.2 Meeting sight distance 3 3 2 18 1 2 3 6 24 61,54 58,33 1.7.3 Overtaking sight distance 3 3 2 18 1 2 3 6 24 61,54 58,33 1.9.1 Dimensions 3 3 2 18 1 2 3 6 24 61,54 58,33 1.9.2 Swept path 2 3 3 18 1 2 3 6 24 61,54 58,33 1.5.2 Acceleration 1 2 2 4 2 2 3 12 16 41,03 57,41 1.1.2 Speed limit approach 2 3 2 12 1 2 3 6 18 46,15 47,22 1.3.3 Object height 3 2 2 12 1 2 3 6 18 46,15 47,22 1.3.4 Lateral object position 3 2 2 12 1 2 3 6 18 46,15 47,22 Annex Road lighting 3 3 2 18 1 1 3 3 21 53,85 45,83 1.1.3 Actual speed approach 3 3 1 9 1 2 3 6 15 38,46 41,67 1.3.2 Lateral eye position 2 2 2 8 1 2 3 6 14 35,90 39,81 1.6.2 Overtaking distance 2 2 2 8 1 2 3 6 14 35,90 39,81 1.2 Reaction time 3 2 1 6 1 2 3 6 12 30,77 36,11 1.7.5 Crossing sight distance 3 2 1 6 1 2 3 6 12 30,77 36,11 1.3.1 Eye height 1 2 2 4 1 2 3 6 10 25,64 32,41 1.1.1 Design speed approach 1 3 1 3 1 2 3 6 9 23,08 30,56 2.3.5.3 Stop areas for brake checking 3 2 3 18 2 2 3 12 30 76,92 83,33 2.3.5.1 Warrants and spacing 2 3 2 12 2 2 3 12 24 61,54 72,22 2.3.5.2 Type and length 2 3 2 12 2 2 3 12 24 61,54 72,22 2.2.3.1 Radii not recommended 3 3 2 18 1 2 3 6 24 61,54 58,33 2.2.3.2 Super elevation 3 3 2 18 1 2 3 6 24 61,54 58,33 2.2.4.4 Internal defects of a bend 3 1 1 3 2 2 3 12 15 38,46 55,56 2.2.4.1 Curve following a straight section 3 2 2 12 1 2 3 6 18 46,15 47,22 2.2.4.2 Compatibility of two successive curves 3 2 2 12 1 2 3 6 18 46,15 47,22 2.2.4.3 Transition curves 2 3 2 12 1 2 3 6 18 46,15 47,22 2.2.4.5 Design consistency 3 2 2 12 1 2 3 6 18 46,15 47,22 2.2.5 Project planning to improve existing roads 3 2 2 12 1 2 3 6 18 46,15 47,22 2.2.3.3 Minimum radius 3 3 2 18 1 1 3 3 21 53,85 45,83 2.3.2.1 Convex curves 3 3 2 18 1 1 3 3 21 53,85 45,83 2.3.1 Gradient 2 3 2 12 1 1 3 3 15 38,46 34,72
2.3.3.2Auxiliary (climbing or passing) lane suppression: type and length of drop
3 2 2 12 1 1 3 3 15 38,46 34,72 2.3.4 Improvement of existing roads 3 1 1 3 1 2 3 6 9 23,08 30,56 2.4 Coordination of horizontal and vertical alignments 2 3 2 12 1 1 2 2 14 35,90 30,56 2.3.3.1 Passing/overtaking lanes (old 3.2.4) 2 2 2 8 1 1 3 3 11 28,21 27,31 2.2.1 Principles 1 1 1 1 1 2 3 6 7 17,95 26,85 2.3.2.2 Concave curves 1 3 2 6 1 1 3 3 9 23,08 23,61 2.2.2 Straight sections and large radius curves 1 1 1 1 1 1 3 3 4 10,26 14,35 3.2.8 Surfacing 3 3 2 18 2 2 3 12 30 76,92 83,33 3.2.3 Crossfall 2 3 2 12 2 2 3 12 24 61,54 72,22 3.6 Tunnels 2 2 2 8 2 2 3 12 20 51,28 64,81 3.2.2.1 Lane width vs design speed 1 3 2 6 2 2 3 12 18 46,15 61,11 3.4.1 Cycle lane 3 3 2 18 1 2 3 6 24 61,54 58,33 3.4.2 General 2 1 2 4 2 2 3 12 16 41,03 57,41 3.2.7 Turnouts,safety zones 1 1 2 2 2 2 3 12 14 35,90 53,70 3.2.1 Road Width 2 3 2 12 1 2 3 6 18 46,15 47,22 3.2.9 Road markings 3 2 2 12 1 2 3 6 18 46,15 47,22 3.3.1 Obstacle-free zones 2 3 2 12 1 2 3 6 18 46,15 47,22 3.4.3 Pedestrian sidewalk 3 3 2 18 1 1 3 3 21 53,85 45,83 3.4.4 Bus stops bays 3 3 2 18 1 1 3 3 21 53,85 45,83 3.3.4 Slopes 1 3 3 9 1 2 3 6 15 38,46 41,67 3.1.3 Integrated design 2 2 2 8 1 2 3 6 14 35,90 39,81 3.5.1 Frontage roads 2 2 2 8 1 2 3 6 14 35,90 39,81 3.3.2 Type of Obstacle 3 1 2 6 1 2 3 6 12 30,77 36,11 3.3.3 Soft shoulders 1 3 2 6 1 2 3 6 12 30,77 36,11 3.2.4.1 Shoulder width suitable for emergency lane 2 1 2 4 2 1 3 6 10 25,64 32,41 3.2.6 Median separation 1 2 2 4 1 2 3 6 10 25,64 32,41 3.2.5 Inner shoulder 1 3 2 6 1 1 3 3 9 23,08 23,61 3.3.5 Drainage channels 2 1 2 4 1 1 3 3 7 17,95 19,91 4.4 Traffic safety records for intersection types 2 3 3 18 2 2 3 12 30 76,92 83,33 4.5.7 Local speed limits 3 3 2 18 2 2 3 12 30 76,92 83,33 4.1.1 Number of arms 2 3 2 12 2 2 3 12 24 61,54 72,22 4.6.2.4 Bicycle facilities 3 2 2 12 2 2 3 12 24 61,54 72,22 4.6.3 Traffic signals 3 2 2 12 2 2 3 12 24 61,54 72,22 4.1.4 Traffic conflict countermeasures for vulnerable road users 2 2 2 8 2 2 3 12 20 51,28 64,81
4.6.2.2Shape and layout (refers to whather it is a traditional t or X or some deviation)
2 2 2 8 2 2 3 12 20 51,28 64,81
4.2 Use of design templates 3 3 2 18 1 2 3 6 24 61,54 58,33 4.3 Design principles 3 3 2 18 1 2 3 6 24 61,54 58,33 4.5.6 Bicycle and pedestrian facilities 3 3 2 18 1 2 3 6 24 61,54 58,33 4.6.2.3 Crossing sight distance requirements 3 3 2 18 1 2 3 6 24 61,54 58,33 4.1.2 Traffic control mode 3 2 2 12 1 2 3 6 18 46,15 47,22 4.5.4 Major road left turn lanes 3 3 2 18 1 1 3 3 21 53,85 45,83 4.1.3 Traffic conflict countermeasures for motor vehicles 2 2 2 8 1 2 3 6 14 35,90 39,81 4.5.8 Crossing sight distance requirements 2 2 2 8 1 2 3 6 14 35,90 39,81 4.6.1 X or Y intersection 2 2 2 8 1 2 3 6 14 35,90 39,81 4.6.2.1 Use 2 2 2 8 1 2 3 6 14 35,90 39,81 4.6.4 Grade separation 3 1 2 6 1 2 3 6 12 30,77 36,11 4.5.1 3- and 4-way 2 3 2 12 1 1 3 3 15 38,46 34,72 4.5.2 Priority control mode 3 2 2 12 1 1 3 3 15 38,46 34,72 4.5.5 Right turn lanes 2 3 2 12 1 1 3 3 15 38,46 34,72 4.5.3 Minor road channelization 2 2 2 8 1 1 3 3 11 28,21 27,31
80
8.3.2 Dual carriageway roads
BASIC ASSUMPTIONS A B C D
Safety effect mentioned?, If so,
how big
Are the effects of deviating from the
norm on safety mentioned/described Total score % Weighted
BASISCRITERIARelevant to
safety
Relevance covered in literature
(Qualitative/descriptive to numerical:
Researchable in regards to
safety
Final score Priority
D=AxBxCIn guidelines?
Total exfxg
(small to large: 1-3) (1-3)Very low to very high
Yes=1, No=2 Yes=1; No=2
No=3; Yes, quanlitative=2; Yes, quantitative=3 Score (Max=12)
1-3)
1.8 Design vehicle characteristics 3 3 3 27 2 2 3 12 39 100,00 100,00 1.4.1 Longitudinal friction coefficient 3 3 2 18 2 2 3 12 30 76,92 83,33 1.4.2 Side friction coefficient 3 3 2 18 2 2 3 12 30 76,92 83,33 1.7.5 Crossing sight distance 3 3 2 18 2 2 3 12 30 76,92 83,33 1.9.4 Safety distances 3 3 2 18 2 2 3 12 30 76,92 83,33 1.7.3 Overtaking sight distance 1 3 3 9 2 2 3 12 21 53,85 66,67 1.7.4 Abort overtaking sight distance 1 3 3 9 2 2 3 12 21 53,85 66,67 1.7.2 Meeting sight distance 1 3 2 6 2 2 3 12 18 46,15 61,11 1.5.1 Deceleration 3 3 2 18 1 2 3 6 24 61,54 58,33 1.9.1 Dimensions 3 3 2 18 1 2 3 6 24 61,54 58,33 1.9.2 Swept path 2 3 3 18 1 2 3 6 24 61,54 58,33 1.1.2 Speed limit approach 2 3 2 12 1 2 3 6 18 46,15 47,22 1.9.3 Overhead and lateral clearances 2 3 2 12 1 2 3 6 18 46,15 47,22 1.9.5 Dynamic lateral clearance 3 2 2 12 1 2 3 6 18 46,15 47,22 1.6.1 Stopping distance 3 3 2 18 1 1 3 3 21 53,85 45,83 1.7.1 Stopping sight distance 3 3 2 18 1 1 3 3 21 53,85 45,83 1.1.3 Actual speed approach 3 3 1 9 1 2 3 6 15 38,46 41,67 1.3.2 Lateral eye position 2 2 2 8 1 2 3 6 14 35,90 39,81 1.5.2 Acceleration 2 2 2 8 1 2 3 6 14 35,90 39,81 1.2 Reaction time 3 2 1 6 1 2 3 6 12 30,77 36,11 1.3.3 Object height 3 1 2 6 1 2 3 6 12 30,77 36,11 1.3.4 Lateral object position 3 1 2 6 1 2 3 6 12 30,77 36,11 1.10 Road image (Rhol=2to7*RBol) 3 1 2 6 1 2 3 6 12 30,77 36,11 1.3.1 Eye height 1 2 2 4 1 2 3 6 10 25,64 32,41 1.1.1 Design speed approach 1 3 1 3 1 2 3 6 9 23,08 30,56 Annex Road lighting 3 1 1 3 1 2 3 6 9 23,08 30,56 1.6.2 Overtaking distance 1 1 2 2 1 2 3 6 8 20,51 28,70 1.11 Recommendations for mitigating barrier effect impacts. 1 1 1 1 1 2 3 6 7 17,95 26,85 2.2.3.1 Radii not recommended 3 3 2 18 1 2 3 6 24 61,54 58,33 2.2.3.2 Super elevation 3 3 2 18 1 2 3 6 24 61,54 58,33 2.2.3.3 Minimum radius 3 3 2 18 1 2 3 6 24 61,54 58,33 2.2.4.1 Curve following a straight section 3 3 2 18 1 2 3 6 24 61,54 58,33 2.2.4.2 Compatibility of two successive curves 3 3 2 18 1 2 3 6 24 61,54 58,33 2.3.2.1 Convex curves 3 3 2 18 1 2 3 6 24 61,54 58,33 2.3.5.1 Warrants and spacing 3 3 2 18 1 2 3 6 24 61,54 58,33 2.2.4.4 Internal defects of a bend 3 1 1 3 2 2 3 12 15 38,46 55,56 2.2.2 Straight sections and large radius curves 2 3 2 12 1 2 3 6 18 46,15 47,22 2.2.4.3 Transition curves 2 3 2 12 1 2 3 6 18 46,15 47,22 2.2.4.5 Design consistency 3 2 2 12 1 2 3 6 18 46,15 47,22 2.3.1 Gradient 2 3 2 12 1 2 3 6 18 46,15 47,22 2.3.3.2
Auxiliary (climbing or passing) lane suppression: type and length of drop
2 3 2 12 1 2 3 6 18 46,15 47,22
2.3.4 Improvement of existing roads 3 2 2 12 1 2 3 6 18 46,15 47,22 2.3.5.2 Type and length 2 3 2 12 1 2 3 6 18 46,15 47,22 2.4 Coordination of horizontal and vertical alignments 2 3 2 12 1 2 3 6 18 46,15 47,22 2.3.3.1 Passing/Overtaking lanes (old 3.2.4) 2 2 2 8 1 2 3 6 14 35,90 39,81 2.3.2.2 Concave curves 1 3 2 6 1 2 3 6 12 30,77 36,11 2.2.1 Principles 2 2 1 4 1 2 3 6 10 25,64 32,41 2.3.5.3 Stop areas for brake checking 1 2 2 4 1 2 3 6 10 25,64 32,41 2.2.5 Project planning to improve existing roads 3 1 1 3 1 2 3 6 9 23,08 30,56 3.2.9 Surfacing 3 3 2 18 2 2 3 12 30 76,92 83,33 3.2.10 Road markings 3 3 2 18 2 2 3 12 30 76,92 83,33 3.7 Tunnels 3 2 2 12 2 2 3 12 24 61,54 72,22 3.2.2.1 Lane width vs. design speed 2 2 2 8 2 2 3 12 20 51,28 64,81 3.2.3 Crossfall 3 3 2 18 1 2 3 6 24 61,54 58,33 3.1.1 Relationship curve radius / superlevation / speed 3 3 2 18 1 2 3 6 24 61,54 58,33 3.2.6 Central reservation 3 3 2 18 1 2 3 6 24 61,54 58,33 3.3.1 Obstacle-free zones 3 3 2 18 1 2 3 6 24 61,54 58,33 3.4 Auxiliary lanes (e.g. bus lanes) 3 3 2 18 1 2 3 6 24 61,54 58,33 3.6 Access control 3 3 2 18 1 2 3 6 24 61,54 58,33 3.8.2 Frontage roads 2 1 2 4 2 2 3 12 16 41,03 57,41 3.2.1 Road Width 2 3 2 12 1 2 3 6 18 46,15 47,22 3.2.4.1 Outside shoulder width suitable for emergency lane 3 2 2 12 1 2 3 6 18 46,15 47,22 3.2.7 Median separation 3 2 2 12 1 2 3 6 18 46,15 47,22 3.2.8 Turnouts,safety zones 3 2 2 12 1 2 3 6 18 46,15 47,22 3.8.3 Rest and service areas 3 2 2 12 1 2 3 6 18 46,15 47,22 3.3.4 Slopes 1 3 3 9 1 2 3 6 15 38,46 41,67 3.1.3 Integrated design 2 2 2 8 1 2 3 6 14 35,90 39,81 3.3.2 Type of Obstacle 3 1 2 6 1 2 3 6 12 30,77 36,11 3.3.3 Soft shoulders 2 3 2 12 1 1 3 3 15 38,46 34,72 3.1.2 Superelevation (transition type / length) 2 1 2 4 1 2 3 6 10 25,64 32,41 3.2.5 Inner shoulder 2 1 2 4 1 2 3 6 10 25,64 32,41 3.3.5 Drainage channels 2 1 2 4 1 2 3 6 10 25,64 32,41 3.5 Recommended cross-sections 2 1 2 4 1 2 3 6 10 25,64 32,41 3.8.1 General 1 1 2 2 1 2 3 6 8 20,51 28,70
4.2.1Maximum absolute value for the grade of the freeway through the interchange area
3 3 2 18 2 2 3 12 30 76,92 83,33
4.2.2Minimum value for horizontal curvature throughout the interchange area
3 3 2 18 2 2 3 12 30 76,92 83,33 4.5.4.1 Turning radii for design vehicle 3 3 2 18 2 2 3 12 30 76,92 83,33 4.5.2
Length of access control along the crossroad beyond the interchange, to ensure its integrity
2 3 2 12 2 2 3 12 24 61,54 72,22
4.5.3Land development and access management measures are in place for the interchange area (Y or N)
3 2 2 12 2 2 3 12 24 61,54 72,22 4.5.4.3 Traffic control 3 2 2 12 2 2 3 12 24 61,54 72,22 4.3.2.1
Requirements for consistency in exit pattern with other nearby interchanges
2 2 2 8 2 2 3 12 20 51,28 64,81
4.3.6.1 Over the freeway 2 2 2 8 2 2 3 12 20 51,28 64,81 4.4.1
Design speed of the ramp ≥50% of the mainline design speed
3 3 2 18 1 2 3 6 24 61,54 58,33
4.2.3Sight distance requirement in advance of each exit (desirably decision sight distance)
3 3 2 18 1 2 3 6 24 61,54 58,33 4.3.5.1 Distance between the physical merge and exit nose? 3 3 2 18 1 2 3 6 24 61,54 58,33 4.4.2 Length for acceleration at entrance ramps 3 3 2 18 1 2 3 6 24 61,54 58,33 4.4.3 Length for deceleration at exit ramps? 3 3 2 18 1 2 3 6 24 61,54 58,33 4.5.4.2 Capacity 3 3 2 18 1 2 3 6 24 61,54 58,33 4.4.4 Balanced number of exit and entrance? 1 1 2 2 2 2 3 12 14 35,90 53,70 4.5.1.1
Traffic control at the crossings at interchange ramps (Y or N)
1 1 2 2 2 2 3 12 14 35,90 53,70 4.1.1 Minimum value for spacing distance? 2 3 2 12 1 2 3 6 18 46,15 47,22 4.1.2
Minimum value for distance between successive entrances and exits?
2 3 2 12 1 2 3 6 18 46,15 47,22
4.3.4Manadtory installation of all exits and entrances on the right side of the freeway mainline?
3 2 2 12 1 2 3 6 18 46,15 47,22
4.5.4.5 Intersection sight distance 3 2 2 12 1 2 3 6 18 46,15 47,22 4.3.7.1 Priority route is the through facility 3 1 3 9 1 2 3 6 15 38,46 41,67 4.5.4.4 Channelization 2 2 2 8 1 2 3 6 14 35,90 39,81 4.3.1.1
An appropriate array of interchange configurations and variations must be evaluated in the design study phase
2 1 2 4 1 2 3 6 10 25,64 32,41
4.3.3Requirement for completeness of directional traffic movements provision
1 2 2 4 1 2 3 6 10 25,64 32,41
1