TRLnew

sCreatingthe future oftransport

For the last 75 years RRL / TRRL / TRL has been at the forefront of developing efficient and effective knowledge-based solutions that have resolved the transport issues of the passing decades.

Today, TRL plays a leading role providing expert advice and consultancy, using new technologies and innovative techniques to meet the demands of the 21st century.

JULY 2008 www.trl.co.uk

In 1925, the Roads Improvement Act permitted the Ministry of Transport (MoT) to “conduct experiments or trials for the improvement of the construction of roads...” The Ministry formed an experimental branch, and in February 1930, opened an Experimental Station at Harmondsworth, near Heathrow.

In 1933, the Experimental Station moved from the MoT to the Department of Scientific and Industrial Research (DSIR) – a move supported by the Chancellor of the Exchequer Neville Chamberlain, who was “definitely of the opinion that the balance of advantage lies in bringing it into closer cooperation with other research activities…” As a result, it was renamed the Road Research Laboratory (RRL).

From the start, our work centred on finding efficient and effective knowledge-based solutions. For example, in 1938 our Director, Reginald Stradling wrote that:

“The objective of all the research work at the Road Research Laboratory is to accumulate that body of scientific knowledge which is an essential factor in the economical and efficient construction and maintenance of our roads. Practical application of the results must be the aim throughout.”

In 1939, RRL was allocated war research. This involved experiments with explosives and projectiles and the rapid construction of roads and airfields using locally produced materials.

Work in the 1940’s included studies of accident data, traffic flow, junction design, pedestrian

crossings, street lighting and vehicle safety. In 1946 RRL’s Road Safety Division was established at Langley Hall near Slough.

RRL’s Colonial Research Section was formed in 1955 and in 1965 RRL was transferred back to the Ministry of Transport, closer to those responsible for transport policy. The Crowthorne office opened in 1967 bringing all the staff together in one location. Over the years our name has changed several times; in 1972, we became the Transport and Road Research Laboratory (TRRL); and in 1992, the Transport Research Laboratory (TRL) when we became an Executive Agency. TRL was privatised in 1996 and is now based in Crowthorne House, its purpose built Head Office with state-of-the-art research facilities.

Throughout this time, our work has depended on close working relationships with our customers and partners. These include Government Departments and Agencies (especially the Department for Transport (DfT), Highways Agency (HA), and their predecessors), highway authorities, universities, other research organisations, trade associations, manufacturers, consultants, contractors and motoring organisations.

The following pages illustrate some aspects of our work. Over the course of this year information on our history will be added to our web site at www.trl.co.uk/75

All the photographs in this edition of TRL News are from our image library.

2 TRLnews

RRL 1933 – TRL 2008

1 Front under-run guard development (c 1990)2 Development of the bouncing bomb, 19423 Bridge parapet development, 19704 Efficiency of snow clearing, 19535 Channel tunnel shuttle test rig, 19716 Evaluating masonry arch bridge strength, 19887 Automatic vehicle guidance, 1961

On 1 April 2008, TRL celebrated its 75th Anniversary. To mark the occasion, this special edition of TRL News focuses on our history and some of our achievements.

4

1

2

6

7

3

5

RRL’s early work in the 1930’s concentrated on road materials and methods of construction. Post war, it expanded to include the mechanisation of road building, bridge and tunnel construction, earthworks, and drainage. Three aspects of our work on road design and testing are highlighted below.

Skidding resistanceWork on skidding resistance began at the National Physical Laboratory in 1927 before being transferred to the Ministry of Transport in 1930 and to RRL in 1933. Our work has included:

l Developing methods of measuring skid resistance. For example, an instrumented motorcycle and sidecar was developed in 1929 to measure the Sideways-Force Coefficient (SFC) – a measure of the co-efficient of friction. The same basic method is still in use today in the form of SCRIM (Sideways-force Coefficient Routine Investigation Machine).

l Investigating the relationship between skid resistance and accidents, materials and traffic flow. This has led to identifying materials with resistance to skidding and developing the UK standards for their use, leading to reduced accidents and injuries.

Road designUntil the mid 1950’s, limitations in capital investment made it difficult to build full scale experimental roads. In 1957, RRL began its first major experiment, monitoring the performance of a 2.25 mile stretch of the A1 at Alconbury, which was built using a range of materials of different thicknesses and strengths. In the following years

many other similar experiments were conducted. At about the same time, we developed weigh-in-motion (WIM) devices which allowed us to relate the deterioration of the road to the weights of vehicles.

In 1960, we drew together all available information in Road Note 29 “A guide to the structural design of flexible and rigid pavements for new roads”. We have regularly updated design guidance since then as data from experiments and experience became available, with LR1132, “The Structural Design of Bituminous Roads,” in 1984, TRL 250 “Long Life Pavements for Heavy Traffic” in 1997, and TRL 615 “Development of a more versatile approach to Flexible and Flexible Composite Pavement Design” in 2004. A fundamental re-look at the approach to pavement design is on-going.

During the 1990’s, we demonstrated that deterioration of thick asphalt roads generally starts at the surface as cracking and rutting, rather than (as previously assumed) from the base of the bound layers. This told us that, provided the surface is maintained, these “long-life” roads should be serviceable well beyond the current design periods, thus reducing maintenance costs and disruption from road works.

Contactless measurement of road characteristicsIn the past, road characteristics (such as rutting, cracking, profile and deflection) were measured either manually or using slow-moving machines. During the last 30 years, we have developed laser and image collection equipment to make these measurements more reliable and cost effective without disrupting traffic. Examples include the Laser Profilometer (mid 1970’s), High-speed Road Monitor (1980’s), and HARRIS (Highways Agency Road Research Information System, 1990’s onwards). HARRIS records the 3D road profile using lasers and can detect cracks as small as 2mm wide using digital video images.

With a need to keep the road network running as smoothly as possible, survey vehicles that can measure the structural strength of roads at traffic speed, are set to become the way forward. TRL is developing for HA the Traffic Speed Deflectometer (TSD), a contactless method of measuring road deflection. The existing Deflectograph vehicles measure the deflection of the road at a speed of about 2.5 km/hr. The TSD, based on Danish technology, uses Doppler lasers to continually measure the deflection velocity of the road surface under its heavy axle, potentially at up to 80 km/hr, thus eliminating any disruption to the traffic flow.

Developing Better RoadsTRLnews 3

1 A1 Alconbury with WIM Sensors, 19652 SFC Motorcyle and Sidecar, 1948 model3 Laser Profilometer, 19754 Harris25 Traffic Speed Deflectometer

4

2

3

5

1

After the war, the scope of RRL widened to include traffic and safety. This included investigating the capacity of roads and junctions. Our work has identified the fundamental factors affecting capacity and has led to the development of tools to assist engineers in the design of roads and junctions. Some examples are given below.

RoundaboutsWork on roundabout capacity began in the mid 1950’s. At that time there were no rules defining driver behaviour at roundabouts. As a result, they tended to “lock” under heavy traffic as vehicles entering the roundabout blocked those leaving it. RRL demonstrated that the introduction of the “offside priority rule” (requiring vehicles entering the roundabout to give way to vehicles already on it) would eliminate locking, increase capacity, reduce delays and more importantly reduce accidents. This rule was introduced in November 1966.

After 1966, we developed smaller roundabout designs, including mini roundabouts, and in 1980, we published a unified formula for predicting roundabout capacity. This was based on studies of 35 different layouts on our test track and 86 roundabouts on public roads. We also developed the ARCADY (Assessment of Roundabout Capacity And DelaY) computer programme which is still used today to test roundabout designs for vehicle capacity, queues, delays and safety.

Traffic lightsFollowing the introduction of traffic light controlled junctions, RRL developed ‘area traffic control,’ starting in 1967 with experimental central computerised control of 80 traffic signals in Glasgow. We have also developed a number of other traffic light control tools, including:

l TRANSYT (TRAffic Network StudY Tool), a software program to find the most appropriate fixed time plans for the coordination of a network of traffic signal controlled junctions, which made linked signals much more effective. Originally developed in the late 1960’s, versions have been distributed to some 45 countries.

l SCOOT (Split, Cycle & Offset Optimisation Technique), an urban traffic system to coordinate traffic signals at networks of junctions. It responds automatically to traffic fluctuations, making it particularly effective in areas where traffic flows are unpredictable, and is used in over 200 towns and cities worldwide.

l MOVA (Microprocessor Optimised Vehicle Actuation), an adaptive control system for traffic signals at isolated junctions. Depending on traffic demand, it intelligently moves between delay -minimising and capacity maximisation modes, and is used at nearly 3,000 sites around the UK.

Managed MotorwaysFor many years we have studied motorway traffic flow, and worked with the HA to optimise journey time. Recent projects include:

l M25 Controlled Motorway (variable speed limit) scheme, which included establishing the traffic flows at which different speed limits should be switched on and off, and monitoring the effectiveness of the scheme (including traffic characteristics, safety, noise, exhaust emissions and driver reactions).

l M42 Active Traffic Management (ATM), including hard shoulder running. We recommended the location for the scheme and evaluated a range of potential operational regimes. We also helped to develop the scheme and monitor its effectiveness.

A valuable tool in our work on motorway traffic flow is Motorway Traffic Viewer (MTV), which was developed by TRL to tackle congestion problems by identifying and evaluating congestion ‘hotspots.’ MTV analyses traffic and signal data from MIDAS (Motorway Incident Detection and Automatic Signalling) loops. Earlier this year, TRL introduced the Costain Traffic Manager (CTM), a web-based application tool which enables informed decisions to be made on managing carriageway capacity through roadworks. Both tools have proved invaluable in meeting the current challenges of increasing traffic demand and the need to ‘keep traffic moving.’

Tackling Congestion4 TRLnews

1 Traffic light capacity trial, 19702 Simulator view of lane signals on the M423 Mini roundabout trial at TRL, 19774 RRL roundabout experiment at Northolt

Airport, 19555 New generation vehicle activated sign

1

2

3

4

5

TRLnews 5

Road safety depends on the interaction of many factors. These include: the road surface; road alignment; junction design; vehicle design and maintenance; roadside “furniture” (including barriers, lamp-posts and signs); driver / rider / pedestrian training, behaviour and impairment; warning and communication systems (signs, navigation systems, etc); and the environment (ice, rain, etc). Over the years, our work has covered all these factors.

Improving Safety

The number of people killed in road traffic accidents in the UK increased from 5,012 in 1950 to a peak of 7,985 in 1966 but then fell to 2,943 in 2007. Over the same period, road traffic increased to 9.5 times the 1950 level and the fatality rate per 100 million vehicle kilometres fell to just 7% of that in 1950. TRL has been involved in many of the initiatives that led to this reduction in casualties.

Accident InvestigationReliable information about accidents is vital to our work on road safety. Over the last 60 years we have conducted many studies, including analyses of national statistics, investigations into particular measures (such as the introduction of the Zebra crossing and drink-driving studies), and On-the-Spot (OTS) accident investigation. Our OTS work began in 1956, with a team attending accidents to record information about damage to vehicles, road conditions and vehicle manoeuvres, etc. Where possible, this was linked to information about the injuries sustained in the accidents. These studies have helped us to identify how accidents and injuries have occurred, leading to the development of effective countermeasures.

Urban SafetyMany projects have been undertaken to reduce road casualties in urban areas. These include the Slough experiment (1950’s), the Urban Safety Project (1980’s) and the Gloucester Safer City (1996-2001). In the 1980’s, we developed Urban Safety Management (USM). This looks at travel patterns across an area and aims to reduce

accidents by defining the appropriate road hierarchy, managing traffic onto the right roads, managing traffic speed, and coordinating all measures that influence road safety.The DfT contracted us to assist in the development of the Gloucester Safer City project and to monitor its results. The USM approach was successfully used, leading to an estimated 24% net reduction in injury accidents.

Safety Quality of Road NetworksWork on the safety of inter-urban roads has included projects for the HA to help them develop their safety strategy and to define Key Performance Indicators. More recently, we coordinated research with European partners to produce EuroRAP (European Road Assessment Programme), a Europe-wide method of assessing road safety. EuroRAP uses information from accidents and on-road inspection of safety features to provide a relative risk rating of main interurban roads. It identifies the highest risk roads and indicates the size and content of the improvement programme required to achieve casualty reduction targets.

In March 2000, the Government set a national target for reducing the number of road accident casualties in Great Britain by the year 2010. The target figures were based on casualty rates forecast by us and the principal challenge is to achieve a significant reduction in road deaths. TRL will continue to work closely with the DfT to monitor the UK’s progress towards casualty reduction.

1 Installing a Zebra Crossing, 19482 Seat Belt Experiment, 19653 Drink Drive Survey, 19654 Pedestrian crossing markings, 19485 Early Driving Simulator, 19766 Accident investigation today

2

3

1

4

5

6

Safer Vehicles TRL is well known for its extensive work in vehicle safety: work that has encompassed braking, skidding, vehicle lighting (head-lights, brake lights, indicators), windscreen glass, driver vision, seat belts, airbags, child seats, pedestrian protection, helmets, heavy goods vehicle safety and modified vehicles.

Frontal Impact Test, 1961

As car ownership increased after the war and with it the rising cost in terms of occupant fatalities and injury, RRL turned its attention to occupant protection.

From analysis of hospital records and accident investigation data during the late 1950’s, evidence emerged of the high incidence of head and chest injuries (for example, from an unrestrained driver hitting the steering wheel). Three-quarters of single vehicle impacts were to the front of the car.

This led to TRL conducting its first full-scale frontal impact tests in 1961, with cars impacting a 114 tonne block at 60 – 70km/hr. Three years later, our work had clearly demonstrated the importance of wearing seat belts and the need to coordinate the design of the seat, seat belt, passenger compartment and crushable front of the car in order to minimise the deceleration experienced by the occupants.

Cars were generally designed with adult passengers in mind and the responsibility of protecting children was left to their

parents. TRL has played a major role in the development of child restraint systems since the early 60’s when they were primarily forward facing, and were either bucket shell seats with integral straps or independent harness systems.

As our knowledge and expertise in crashworthiness expanded, TRL became involved with developing representative European front and side impact tests. Real accidents tend to involve only part of the front of the car colliding with an object that yields (such as the front of another vehicle). As part of a European working group, TRL helped to develop an offset frontal impact test (only 40% of the car overlapping the barrier face) into a deformable barrier, producing results very close to those seen in car-to-car collisions.

Similarly, we participated in the working group that developed a side impact test and helped to design the European Side Impact Dummy, EuroSID. The new front and side impact EU Directives came into force in 1998.

In parallel, in 1994, we proposed to the DfT that it should consider starting a New Car Assessment Programme (NCAP) based on the new European impact test methods. This led to the formation of Euro NCAP, which gives star ratings for a car’s safety performance. TRL became the first centre to conduct such tests.

Most recent research has included looking at the issues of compatibility - how vehicles interact with each other at the time of impact, collision avoidance technology and electronic stability control (ESC). TRL is also developing an on-line resource for the DfT to collate information on the developments of vehicle based safety systems. Known as Technology Watch, TRL will flag the most pertinent data, allowing the Department to draw up a shortlist of technical areas or products which will potentially have the most effective impact on road users.

Pedestrians currently account for about one in five of the nearly three thousand killed and 28,000 seriously injured each year in road traffic accidents in the UK.

Research at TRL has looked at how vehicles can be engineered to make them less injurious to pedestrians, research which has benefited other vulnerable road users such as pedal cyclists and motorcyclists. In April this year, TRL launched SensorLegTM, a new biofidelic leg impactor for use in testing and developing sensor technology employed in active safety pedestrian systems.

Euro NCAP Frontal Impact Test

Reducing Environmental ImpactsTRL’s Centre for Sustainability (C4S) leads our knowledge and understanding in environmental performance, strategic environmental assessment and sustainability, covering a broad range of disciplines that have evolved and emerged over time, keeping pace with changing needs.

Quiet Heavy Vehicle, 1976

As traffic volumes increased in the 60’s and 70’s, there was a corresponding increase in the amount of noise generated. In the 1970’s, RRL led the consortium that developed the first prototype QHV (Quiet Heavy Vehicle) to meet the current European noise limit. In the mid-90’s, TRL developed methods for assessing the influence of road surfaces on traffic noise, paving the way for the development of low-noise road surfaces. This helped the HA to effectively mitigate the noise from high-speed roads. More recently, TRL has played a major role in developing the methodology used for mapping UK road and rail noise.

Our streets make up a huge proportion of readily accessible public space and it is important that vulnerable road users are protected. TRL has developed the HA vulnerable road user audit guidance, helping to ensure that the needs of vulnerable road users are taken into account throughout the design and implementation of road schemes. TRL has also looked at the needs of pedestrians and on behalf of Transport for London and the London Boroughs has developed

the Pedestrian Environment Review System (PERS) which audits and reviews streets to assess how well they meet the needs of pedestrians and identifies priorities for investment.

In 2006, TRL took the leading research role in the DfT’s Manual for Streets helping to ensure the necessary components to street design were sustainable, reduced traffic speeds and accidents and contributed to an enhanced sense of place.

The issue of sustainability, the desire to use recycled and secondary materials wherever possible and the need to minimise waste, has been strongly championed by TRL. Emanating from early work in the mid-90s, TRL has developed specifications and guidance for a range of recycled and secondary aggregates, including construction and demolition waste. In 2006, working for the Waste & Resources Action Programme (WRAP) and the construction industry, we developed and implemented a template for Site Waste Management Plans (SWMP) for general and civil engineering projects. With the introduction of new SWMP regulations in April of this year, TRL is able to help organisations by offering training and assistance with the implementation of their plans.

Air quality is another key area of work for TRL. In the 1970s we developed and deployed the UK’s first continuous mobile ambient air pollution monitoring unit and developed the air pollution impact assessment methodology used in the Design Manual for Roads and Bridges (DMRB). In parallel, we devised the UK’s road transport emission factors which are still widely used in modelling and forecasting work.

Climate change will arguably have one of the greatest impacts in the future. We are actively engaged in adaptation and mitigation work to provide an effective response to this challenge. For example, in work for the DfT, TRL has looked at the impact of climate change on local authority roads and identified actions that could be taken to minimise the effects. We help organisations respond to the challenge of climate change, by providing advice, practical applications and training.

TRLnews 7

For further information email: enquiries@trl.co.uk or visit www.trl.co.uk Compiled quarterly by TRL’s Communications Team

TRL HEAD OFFICECrowthorne House Nine Mile Ride Wokingham Berkshire RG40 3GA United KingdomTel: +44 (0)1344 773131 Fax: +44 (0)1344 770356

PRESS OFFICE ENQUIRIES+44 (0)1344 770141 / 0514pressoffice@trl.co.uk

GENERAL ENQUIRIES+44 (0)1344 773131 enquiries@trl.co.uk

TRL LIBRARY+44 (0)1344 770203info@trl.co.uk

TRL SCOTLAND

Tel: +44 (0)131 455 5040Fax: +44 (0)131 455 5047Craighouse Campus Craighouse CourtEdinburgh EH10 5LG

TRL WALES

Tel: +44 (0)29 2066 0117Fax: +44 (0)1344 770356Sophia House 28 Cathedral RoadCardiff CF11 9LJ

Creating the future of transport

Improving Transport in Developing Countries

8 TRLnews

We have contributed to world-wide knowledge in a number of key areas:

Road design and constructionThe soils and road-building materials in tropical countries are significantly different to those in temperate zones. As a result, research on materials properties has always been an important part of our work. This has led to the development of appropriate material tests and standards. A key publication is ORN31 “Guide to the Structural Design of Bitumen-Surfaced Roads”, which is now in its fourth edition, and is the standard design tool in many countries.

Road planningWe undertook ground-breaking research in Kenya that, for the first time, established the quantitative link between vehicle operating costs and road deterioration. This enabled us to develop the first of the life-cycle cost models now in use as HDM-4. Our contribution has been fundamental to the world-wide adoption of a standard tool for road planning and investment decision-making.

Road maintenanceThe work that led to HDM-4 also identified the key importance of road maintenance because of its impact on the rates of return of different types of road investment. Good road maintenance depends on the multi-dimensional issues of attitudes, finance, staffing, management and institutional arrangements. Our ORN1 “Road Maintenance Management for District Engineers” was one of the world’s first documents to recognise that the management issues were more important and difficult than the related technical issues. It is now in its third edition and over 10,000 copies have been issued in three languages.

SafetyRoad safety is a key area where our work has had a huge impact world-wide. Our research was among the first to identify the catastrophic traffic accident rates in developing countries, with the consequent physical and social costs. Addressing accident problems requires complex multi-dimensional institutional measures as well as improved physical traffic engineering. Our landmark publication “Towards Safer Roads in Developing Countries” has provided key guidance on traffic engineering measures.

Another important area of work was the development of MAAP (Microcomputer Accident Analysis Package), which provides tools for collecting basic accident data and for processing this to identify appropriate countermeasures. MAAP is widely used by police forces and traffic accident teams all around the world.

Our involvement in developing countries began in 1955 and has two main elements. Firstly, investigating the particular problems of transport in developing countries, and secondly, disseminating information through courses and publications. For example, the annual Tropical Roads Course has been held in the UK and at various venues around the world for over 30 years. The Overseas Road Note (ORN) series of guidance documents, introduced in 1981 can be found in the offices of thousands of transportation professionals around the world. These and other key documents are now available as downloads from the web.