NATIONAL HIGHWAY AUTHORITY Pavement Design Report (Revised) PESHAWAR – TORKHAM SECTION - I Consultancy Services for Feasibility Study and Preliminary Design of Peshawar-Kabul Motorway 10-Sep-18 Associated Consultancy Centre (Pvt.) Ltd. (ACC) in association with SAMBO Engineering Co. Ltd. (South Korea), ACE-TES & Assign
Pavement Design Report (Revised)10-Sep-18
(ACC) in association with SAMBO Engineering Co. Ltd. (South
Korea),
ACE-TES & Assign
Pavement Design Report (Revised)
M/s ACC in association with M/s SAMBO, M/s ACE-TES & M/s Assign
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Table of Contents
CHAPTER 2 – PAVEMENT EVALUATION AND DESIGN
............................................................................
4
2.1 Design Criteria
........................................................................................................................
4
2.2.1 Description of Field and Laboratory Work
.....................................................................
4
2.2.2 Borrow Sources
..............................................................................................................
5
2.2.3 Quarry Sources
...............................................................................................................
6
2.3.1 Design Methodology:
.....................................................................................................
7
2.4 Design Parameters:
................................................................................................................
7
2.4.1 Design Life
......................................................................................................................
7
2.4.2 Design Traffic
..................................................................................................................
8
2.4.3 Reliability (R)
...................................................................................................................
8
2.4.5 Standard Normal Deviation (ZR)
.....................................................................................
9
2.4.6
Serviceability...................................................................................................................
9
2.5.1 Traffic Volume
..............................................................................................................
11
2.5.2 ESALs Computation
......................................................................................................
12
2.5.4 Computation of Pavement Design and Layer Thicknesses
........................................... 15
2.5.5 Pavement Design;Peshawar –Torkham Motorway
...................................................... 16
2.5.6 Pavement Thickness Design Optimization
...................................................................
16
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2.6 Rigid Pavement Design
.........................................................................................................
17
2.6.1 Modulus of Subgrade Reaction
....................................................................................
18
2.6.2 PCC Elastic Modulus
.....................................................................................................
18
2.6.3 Load Transfer Coefficient
.............................................................................................
19
2.6.4 PCC Modulus of Rupture
..............................................................................................
19
2.6.5 Pavement Thickness Design
.........................................................................................
19
2.6.6 Slab Length and Reinforcement
...................................................................................
19
2.6.7 Design of Tie Bars
.........................................................................................................
20
2.6.8 Design of Dowel Bars
....................................................................................................
21
2.6.9 Contraction Joint
..........................................................................................................
21
2.6.10 Expansion Joint
.............................................................................................................
22
2.7 Pavement Drainage Design
..................................................................................................
23
2.7.1 Surface Drainage Design
...............................................................................................
24
2.7.2 Subsurface Drainage Design
.........................................................................................
25
Annexure A: Soil Investigation Testing Summary for Proposed
Alignment of Motorway ............... 27
Annexure B: Material Testing Summaries of Borrow Material &
Aggregate Quarry Sources ......... 28
Material Testing Summaries of Borrow Material & Aggregate
Quarry Sources .............................. 29
Annexure C: Average Annual Daily Traffic (AADT)for Peshawar –
Torkham Motorway .................. 30
Annexure D: Typical Pavement Cross Sections
................................................................................
31
Annexure E: List of Lined Drain & Brest Wall
...................................................................................
34
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LIST OF FIGURES FIGURE 1: PROJECT ALIGNMENT OF PESHAWAR – KABUL
MOTORWAY PROJECT
......................................................................
2
FIGURE 2: PERCENTAGE CBR AGAINST EACH TEST PIT LOCATION
..........................................................................................
5
FIGURE 3: ESAL’S CONTRIBUTIONS OF VARIOUS CLASSIFIED VEHICLES
................................................................................
14
LIST OF TABLES TABLE 1: PROJECT SECTIONS OF PESHAWAR – KABUL
MOTORWAY PROJECT
...........................................................................
3
TABLE 2: LABORATORY CBR RESULTS AT TEST PIT LOCATIONS
.............................................................................................
5
TABLE 3: LABORATORY CBR TEST RESULTS AT BORROW PIT LOCATIONS
................................................................................
6
TABLE 4: STANDARD NORMAL DEVIATION W.R.T VARIOUS LEVELS OF
RELIABILITY
...................................................................
9
TABLE 5: RECOMMENDED VALUES OF DRAINAGE COEFFICIENTS OF UNTREATED
BASE AND SUB-BASE MATERIALS ....................... 11
TABLE 6: AXLE LOAD SURVEY/EQUIVALENCY FACTORS
....................................................................................................
12
TABLE 7: FORECASTED EQUIVALENT SINGLE AXLE LOAD (ESAL) APPLICATIONS
FOR PESHAWAR – TORKHUM MOTORWAY ............ 13
TABLE 8: SUMMARY OF DESIGN
PARAMETERS.................................................................................................................
14
TABLE 9: DESIGN THICKNESS OF PAVEMENT STRUCTURE AGAINST SUB-GRADE
CBR = 10% .....................................................
16
TABLE 10: DESIGN THICKNESS OF PAVEMENT STRUCTURE AGAINST SUB-GRADE
CBR = 15% ...................................................
17
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CHAPTER 1 - INTRODUCTION
1.1 General
Associated Consultancy Centre (Pvt.) Ltd. Islamabad as the lead
firm has associated
with SAMBO Engineering Korea, Associated Consulting Engineers-TES
(ACE) and
Assign Consulting Engineering International for providing
Consultancy Services for
Feasibility Study and Preliminary Design of Peshawar-Kabul Motorway
Section-I:
Peshawar- Torkham 50 Km, Section-Il: Torkham-Jalalabad 76 Km,
Section-III:
Jalalabad-Kabul 155 Km. The Contract Agreement between the JV
venture and
NHA has been signed on 13th March, 2017.
The firms have worked together on previous projects and have
good
understanding of the project and Client’s requirements. The team of
experts
selected for the project has been chosen with a strong emphasis on
experience
and the proven ability to generate innovative, efficient and
effective solutions to
the problems that may arise during project implementation.
Associated Consultancy Centre (ACC) was established in 1986 and is
one of the
largest Consultancy firms of the country working in multi sector of
engineering
since last 25 years. ACC has completed over 120 projects out of
which 50 projects
are in major highway projects.
Sambo Engineering Co., Ltd. (SAMBO) was founded in 1993 with the
company
slogan, “Producer of Social Environment”. SAMBO is duly
incorporated under the
laws of Korea and is an independent company totally owned by
individual
shareholders. It is the fastest-growing firm and became one of the
leading
consulting firms in Korea extending its services worldwide.
Associated Consulting Engineers ACE (Private) Limited established
in 1958 is one of
the oldest and the largest private sector multidisciplinary
consulting houses in
Pakistan. Since its inception, ACE has provided engineering
consultancy services
for over 1400 projects in various engineering and architectural
disciplines both
within the country and abroad with a capital outlay of about US$
38.0 Billion.
ACE has contributed considerably in the sector of Transportation
Engineering. ACE
was part of JV/ Consortium for the supervision of 6-lane 375 Km
Lahore–Islamabad
Motorway (Pakistan) which included various River and Canal
Bridges,
Flyover/Interchange Bridges and supervised the 1.5 sections out of
4 Sections of
project.
M/s Assign Engineering Consult International (Pvt.) Ltd. is an
associate firm which
is a rapidly growing organization. Their principals bring
exceptional project
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management, design and supervision experience to the group having
been directly
responsible for managing large scale Rural Road Projects including
FMR-I, FMR-II &
RAR-I all over Pakistan. They are currently completed the ADB
Assisted Project
Management Consultancy (PMC) Project in Sindh.
The subject report has been prepared as the "Pavement Design
Report" as
required by the deliverables of the TOR of the project. This report
only includes
the Pavement Design of Section-1 from Peshawar to Torkham.
1.2 Objectives of the Project
The project aims at the feasibility study of construction of
Peshawar – Kabul
Motorway to provide a faster and comfortable travel facility
between two
countries. National Highway (N-5) and Indus Highway (N-55) are the
most
important direct routes in the country linking the International
Sea Port on the
extreme southern end of the country (Karachi) with Torkham, the
International
border on the north. Motorway (M-1), National Highway (N-5) and
Indus Highway
(N-55) all have end point at Torkham Border Peshawar city.
In order to promote the International Trade through our ports,
superior road
network is essential therefore, NHA decided to start the Peshawar
Torkham
Motorway Project on priority basis to attract the International
Trade Traffic for
middle-east market and other parts of the world.
Following map shows the project alignment between Peshawar and
Kabul:
Figure 1: Project Alignment of Peshawar – Kabul Motorway
Project
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1.3 Project Scope of Work The Peshawar-Kabul Motorway shall connect
Peshawar with Kabul through
Torkham and Jalalabad. The project road under this project can
broadly be
classified as Principal Arterial, which shall serve major traffic
flow in between
Peshawar and Torkham. The scope of consultancy as defined in TOR is
to conduct
feasibility study and preliminary design of subject motorway. The
consultant has
carried out Reconnaissance Survey using high definition imagery and
a field visit to
Peshawar – Torkham section as per TOR to finalize the alignment.
Moreover, all
necessary surveys, designs and estimates will be finalized and
feasibility report
generated after the approval of the alignment.
Total Length of the existing road from Peshawar (Hayatabad) to
Kabul (Abdul Haq
Square) is approximately 281 Km1. The most part or the road is
passing through
the mountainous ranges. The project is divided into three sections
which are as
follows:
Sr. No. Section Name of Section Length (KM)
1 Section - I Peshawar – Torkham (Pakistan) 50
2 Section – II Torkham – Jalalabad (Afghanistan) 76
3 Section - III Jalalabad –Kabul (Afghanistan) 155
This report contains the work of Pavement Design for Peshawar -
Torkham Section
I.
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CHAPTER 2 – PAVEMENT EVALUATION AND DESIGN
2.1 Design Criteria
The established general design criteria which have been used for
developing the
detail design. We recognize that the criterion has been developed
with the
following aims in mind:
To provide comfortable stress-free driving environment to road
users
To provide the highest practical and feasible level of road
safety
To accommodate existing and future traffic needs
To accommodate local weather, terrain and soil conditions
To meet international design standards
To minimize future maintenance requirements, and
To minimize adverse community and environmental impacts
The design criteria adopted is in accordance with the AASHTO design
standards
and specifications.
2.2 Soil Testing and Analysis
Soil testing and analysis is an important parameter for carrying
out the pavement
design. The soil testing was performed for the detailed analysis of
in-situ materials
by the Design Team.
Preliminary geological/soil investigation for the project includes
the collection of
samples by digging pits at 5 km intervals along the proposed
alignment of the
motorway. Total 10 soil samples were collected from the site and
then transported
to the ACC Laboratory, Islamabad, where detailed testing was
carried out to
determine the various properties of the materials to be used for
the purpose of
road construction. However, CBR testing was performed on five
samples out of
ten. The preparation of test result summaries attached as
Annexure-A concluded
the preliminary investigations.
Minimum obtained CBR of the natural ground was 13% @ 95% MDD
(AASHTO T-
193). Following Table & Graph shows the results of CBR values
at test pit locations.
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Table 2: Laboratory CBR Results at Test Pit Locations
Pit No
density C.B.R. value (%) at
(Km) AASHTO Unified MDD
2 8+100 A-1-a GP 2.214 7.6 41.0 25.0 5.3
3 13+050 A-2-4 GP 2.202 7.4 56.0 34.8 11.3
4 17+800 A-2-6 GW-GC 2.213 6.7 33.5 22.2 11.2
8 38+300 A-4 CL 2.077 9.9 21.7 13.0 2.6
9 42+600 A-2-4 GC 2.163 8.8 47.0 24.3 9.5
Figure 2: Percentage CBR against each Test Pit Location
2.2.2 Borrow Sources
Borrow materials should be checked for the provision of
embankment/suitable fill
material. Based on the adequacy of the sources, the relative
haulage distances will
be used wherever required for both the roads. Five (05) different
borrow sources
have been identified along the proposed alignment.Out of five; four
sources are
non-plastic with A-1-a soils. Their CBR values meet the desired
requirements for
preparation of embankment. However they may be retested prior to
use for
further verifications. Test results of borrow sources show CBR
values vary from
20% to 50% @ 95% of MDD.Following Table & Graph shows the
results of CBR
values at borrow pit locations along the proposed alignment.
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
8+100 13+050 17+800 38+300 42+600
C B
CBR Value at 95% MDD
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Table 3: Laboratory CBR Test Results at Borrow Pit Locations
Pit No.
density C.B.R. value (%) at
(Km) AASHTO Unified MDD
1 6+000 A-1-a GP 2.260 6.8 43.3 31.0 16.2
2 10+500 A-1-a GP 2.210 6.6 48.2 23.7 10.5
3 27+500 A-1-a GP 2.330 5.4 69.8 50.7 23.0
4 38+000 A-2-4 GC 2.261 7.0 44.5 31.3 17.5
5 46+700 A-1-a GW - GM 2.290 5.6 56.2 43.5 22.9
2.2.3 Quarry Sources
Two aggregate quarries (Crusher Plants) near Km 10+000 & Km
27+500were
identified during the site visit which can be used for this
project. The aggregates
produced by the material yards are of very good quality, able to
meet the
requirements of the road bed, pavement and other aspects of the
road and in rich
reserves. Test results of subject quarries are attached as
Annexure-B.
2.2.4 Sand
Lawrencepur produces good sand which can be used to produce high
quality
concrete.
0.0
10.0
20.0
30.0
40.0
50.0
60.0
6+000 10+500 27+500 38+000 46+700
C B
CBR Value at 95% MDD
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2.3 Flexible Pavement Design
Flexible pavement structural design is a daunting task. Although
the basic
geometry of a pavement system is quite simple, everything else is
not. Traffic
loading is a heterogeneous mix of vehicles, axle types, and axle
loads with
distributions that vary with time throughout the day, from season
to season, and
over the pavement design life. Pavement materials respond to these
loads in
complex ways influenced by stress state and magnitude, temperature,
moisture,
time, loading rate, and other factors. Exposure to harsh
environmental conditions;
ranging from subzero cold to blistering heat and from parched to
saturated
moisture states, adds further complications.
2.3.1 Design Methodology:
For design of flexible pavement structure of project road “AASHTO
Guide for
Design of Pavement Structures (1993)” has been used. Layer
thicknesses have
been calculated through by using AASHTO design equation through
computer
program.
2.4 Design Parameters:
The most important aspect of pavement design is to define the
design factors needed for
any design methodology. Following are the major Design Parameters
required for using
AASHTO 1993 pavement design method.
2.4.1 Design Life
Design life or performance period of the pavement is the period of
time that an
initial pavement structure will last before it needs
rehabilitation. It is important to
note that in actual practice the performance period can be
significantly affected by
the type and level of maintenance applied. The design life of the
project road is
considered 10 years and all design calculation are based on 10
years design life.
Longer design lives, such as 20 years are usually in situations
when we have better
control over the design factors. These design factors include
traffic, material
properties, environment and the sub-grade material properties. The
properties of
material are relatively reliable however; traffic estimate is not
much reliable
because various factors affect the traffic and its growth.
Moreover, the design
ESALs values are too much higher due to thousands of heavy trailers
using the
road daily with very high value of ESAL damage factors. Similarly,
In Pakistan the
pavements are very much prone to rutting due to severe weather.
Therefore, a
period longer than 10 years is not feasible.
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2.4.2 Design Traffic
The design procedure for highways is based on cumulative expected
18-kip
equivalent single axle loads (ESAL) during the analysis
period/design life. The
pavement design is function of traffic and material properties.
Therefore, a careful
and accurate estimate of design traffic plays a vital role in the
performance of
pavement structure. Volume and type of estimated design traffic
also plays a basic
role in selection of pavement type, materials and even design
period. The design
traffic has been estimated through classified traffic counts
carried out in April,
2017.The total numbers of calculated ESALs for the design life of
10 years are
28.44 million for Peshawar – Torkham Motorway however; the value
for pavement
design calculations has been selected as 30 million.
2.4.3 Reliability (R)
Reliability is a mean of incorporating some degree of certainty
into the design
process to ensure that the various design alternatives will last
the analysis period.
The reliability design factor accounts for chance variations in
traffic prediction and
performance prediction, and therefore provides a predetermined
level of
assurance that pavement section will survive the period for which
they were
designed. A design reliability level of 90% has been adopted for
flexible pavement
design of this project.
2.4.4 Standard Deviation (S)
The reliability factor is a function of the overall standard
deviation that accounts
for standard variation in materials and construction, the probable
variation in the
traffic prediction and the normal variation in pavement performance
for a given
design traffic application.The AASHTO guide for design of pavement
structures
states:
The estimated overall standard deviation for the case where the
variance of the
projected future traffic is considered (along with other variance
associated with
revised pavement performance models) are 0.39 for rigid and 0.49
for flexible
pavements.
The estimated overall standard deviation for the case where the
variance of the
projected future traffic is not considered (along with other
variance associated
with revised pavement performance models) are 0.34 for rigid and
0.44 for flexible
pavements.
The range of S value provided in AASHTO design guide are based on
the values
identified above.
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0.30 – 0.40Rigid Pavement
0.40 – 0.50Flexible Pavement
A value of 0.45 has been used for the design and analysis of
flexible pavement.
2.4.5 Standard Normal Deviation (ZR)
The ZRvalue corresponding to reliability (R) of 90% is -1.282 which
has been
adopted in the design which is based on the recommended values of
standard
normal deviation (ZR) by AASHTO Guide for design of pavement
structures 1993.
Following Table shows the standard normal deviation (ZR) values
against reliability
(R).
Table 4: Standard Normal Deviation w.r.t Various Levels of
Reliability
Reliability
60 -0.253 94 -1.555
70 -0.524 95 -1.645
75 -0.674 96 -1.751
80 -0.841 97 -1.881
85 -1.037 98 -2.054
90 -1.282 99 -2.327
91 -1.340 99.9 -3.090
92 -1.405 99.99 -3.750
Serviceability is a Performance criteria which represent the
user-specified set of
boundary conditions within which a given pavement design
alternative should
perform.Initial and terminal serviceability indices have been
established to
compute the total change in serviceability that will be used in the
design
equations.
Initial Serviceability Index( Po)
The initial serviceability index is a function of pavement design
and construction
quality. For flexible pavement design typical value as recommended
by AASHTO
Road Test is 4.2 which have been adopted.
Terminal Serviceability Index (Pt)
The terminal serviceability index is the lowest index that will be
tolerated before
rehabilitation; resurfacing or reconstruction becomes necessary at
this stage.It
generally varies with the importance or functional classification
of the pavement.
Recommended value of terminal serviceability index is 2.52 for the
project road.
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2.4.7 Resilient Modulus (MR)
SUBGRADE:The AASHTO method for pavement design uses the Modulus
of
Resilience (MR) of sub-grade as strength parameter. Different
methods can be
adopted to determine the sub-grade modulus of resilience however;
based upon
CBR value of sub-grade, following TRRL correlation has been used
for
determination of Design MRof Sub-grade:
MR = 2555×(CBR) 0.64 Eq. (1)
GRANULAR SUB-BASE & AGGREGATE BASE: In the absence of the
actual test data
for sub-base material, an engineering estimate is made and the
modulus of the
sub-base material has been estimated.The NHA general specifications
proposed
the CBR value for the granular sub-base as 50%. Therefore,
estimated/selected
modulus value of granular sub-base corresponds to the CBR value has
been taken
as 18,000 psi. (AASHTO Guide for Design of Pavement Structures,
Figure 2.7). For
aggregate base course (ABC), an estimated value of 28,000 psi has
been used for
the CBR equal to80%.
ASPHALT CONCRETE: In the absence of real life data for asphalt
concrete in
Pakistan, these assumptions get trickier, as you get into
visco-elastic materials
such as bitumen stabilized base and asphalt concrete. Normally the
stiffness of the
asphalt concrete mix is found by carrying out bending beam tests in
the laboratory
and procedures such as; those outlined in the Shell pavement design
manual.
However, at high temperatures, these tests give very low moduli
values. In
comparison, the values seen, at the same temperatures, by back
calculating
pavement deflection data are much higher. Therefore, we assumed a
value of
400,000 psi for the resilient modulus of asphalt concrete. The
assumed moduli
values are on lower side to add a factor of safety in the flexible
pavement design.
2.4.8 Layer Coefficients (ai)
A value of layer coefficient is assigned to each layer material in
the pavement
structure in order to convert actual layer thicknesses into
structural number (SN).
The layer coefficient expresses the empirical relationship between
SN and
thickness and is a measure of the relative ability of the material
to function as a
structural component of the pavement. The following general
equation for
structural number reflects the relative impact of layer
coefficients (ai) and
thickness (Di).
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The following layer coefficients have been used in the pavement
design of
Motorway project (AASHTO Guide for Design of Pavement Structures
1993; Figure
2.5,2.6&2.7):
Aggregate Base Course, a2 =0.14/inch (0.055/cm)
Granular Sub-base, a3=0.12/inch (0.047/cm)
2.4.9 Drainage Coefficients (mi)
Depending on the quality of drainage and the availability
ofmoisture, drainage
coefficients m2 and m3 should be applied to granular bases and
sub-bases to
modify the layer coefficients (The possible effect of drainage on
the asphalt
concrete surface course is not considered). As the project road
passes through
areas prone to drainage problems, most of the time pavement
structure could be
exposed to moisture at saturation level, therefore, it is
conservative to assume a
value 1 for the unbound layers having good quality of drainage.
Following Table
shows the recommended values of drainage confidents of untreated
base and sub-
base materials in flexible pavements.
Table 5: Recommended Values of Drainage Coefficients of Untreated
Base and Sub-base Materials
Quality of
Percentage of Time Pavement Structure is Exposed
to Moisture Levels Approaching Saturation Rating Less than 1% 1~5%
5~25% Greater than 25%
Excellent 1.40~1.35 1.35~1.30 1.30~1.20 1.20
Good 1.35~1.25 1.25~1.15 1.15~1.00 1.00
Fair 1.25~1.15 1.15~1.05 1.00~0.80 0.80
Poor 1.15~1.05 1.05~0.80 0.80~0.60 0.60
Very poor 1.05~0.95 0.95~0.75 0.75~0.40 0.40 * AASHTO Guide for
Design of Pavement Structures Table 2.4
2.5 Pavement Design Calculations
In order to carry out flexible pavement design, following
calculations have been
done:
2.5.1 Traffic Volume
Traffic studies for new highway projects are intended to provide
necessary input
data for determination of the magnitude and the pattern of the
traffic load for the
project road through the design period. This involves collection,
verification and
analysis of the traffic data. From the collected data, the
projected traffic for the
design life is calculated and converted into Equivalent Standard
Axle Loads (ESAL)
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for the structural design of pavement. The projected traffic data
for Peshawar –
Torkham Motorway is attached as Annexure-C.
2.5.2 ESALs Computation
The damage caused by vehicles to a road depends on the axle loads
and wheel
configuration of the vehicles. It is therefore important to
determine the axle load
of heavy commercial vehicles in the projected traffic mix that will
likely to use
proposed alignment over the design life. For pavement design
purpose the
damaging power of axles is related to a standard axle of 8.16 tons
(18000 lbs.)
using equivalency factors as described below.
Equivalency Factor= [Actual weight on the axle (lb)/18000x]
The value of "x" used in Road Note 31 is 4.5 whereas; referred to
AASHTO guide
foe design of pavement structures and Road Note 29, it is based on
AASHTO Road
Test and varies from 3.8 to 4.1depending on the axle load, desired
terminal
serviceability index and pavement structure.For calculation of
equivalency factors
the value of“x” was used as 4.
In order to determine the cumulative axle load damage that a
pavement will
sustain during its design life, it is necessary to express the
total number of heavy
vehicles that will use the road during the design period in terms
of the cumulative
number of equivalent standard axles load (ESAL). Following Table
shows the
damaging factors for computation of equivalent number of axles
(ESALs) with
80:20 ratio of Loaded: Empty vehicles.
Table 6: AXLE Load Survey/Equivalency Factors 2
Description Loaded Unloaded Mini Truck 2.52 0.042 2-Axle 4.67 0.052
3-Axle 8.84 0.075
Articulated Trucks
3-Axle 9.6 0.272 4-Axle 10.35 0.385 5-Axle 10.35 0.495 6-Axle 10.84
0.505
* NTRC Axle Load Study 1995
The following equation has been used to determine the traffic
(Wt18) in the design
lane:
2NTRC Axle Load Study
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Where;
Wt18= The cumulative 18-kip ESAL axles;
DD= A directional distribution factor, expressed as a ratio, that
accounts for
thedistribution of ESAL units by direction;
DL = A lane distribution factor, expressed as a ratio, that
accounts for
distribution oftraffic when two or more lanes are available in one
direction;
AADT =the annual average daily traffic.
According to AASHTO Guide for Design of Pavement Structures (1993),
the value of
DD is used as 0.5 and the value of DLis usedas0.9. Following
Tablesshow the
estimated number of ESALs during the design lifeof Peshawar –
Torkhum
Motorway.
Table 7: Forecasted Equivalent Single Axle Load (ESAL) Applications
for Peshawar – Torkhum Motorway
Year Vehicle
Type Buses
Damaging
Factor
Loaded 0.767 2.52 4.67 8.84 9.26 10.35 10.35 10.84 ESALs ESALs
ESALs
Empty 0.042 0.052 0.075 0.092 0.385 0.495 0.505
2017 Base Year 7 57 361 136 65 135 70 474 3,210,040 3,210,040
1,444,518
2018 Const. Period
7 61 386 146 70 145 75 507 3,435,984 6,646,024 2,990,711
2019 8 65 413 155 74 154 80 542 3,668,889 10,314,913
4,125,965
2020 1 10 124 495 184 88 185 94 677 4,505,392 14,820,305
5,928,122
2021 2 11 132 527 196 94 197 101 721 4,800,419 19,620,724
7,848,290
2022 3 11 140 562 209 100 210 107 768 5,114,767 24,735,491
9,894,197
2023 4 12 149 598 223 107 223 114 818 5,449,701 30,185,193
12,074,077
2024 5 12 159 637 237 114 238 122 872 5,806,570 35,991,762
14,396,705
2025 6 13 170 679 253 121 254 130 929 6,186,809 42,178,571
16,871,429
2026 7 13 180 722 269 129 270 138 988 6,577,726 48,756,297
19,502,519
2027 8 14 192 768 286 137 287 147 1050 6,993,345 55,749,642
22,299,857
2028 9 14 204 816 304 146 305 156 1117 7,435,227 63,184,869
25,273,948
2029 10 15 217 868 323 155 324 166 1187 7,905,032 71,089,901
28,435,960
2030 11 16 231 923 343 165 345 176 1262 8,404,524 79,494,425
31,797,770
2031 12 16 245 979 364 175 366 187 1339 8,918,774 88,413,198
35,365,279
2032 13 17 260 1039 387 186 388 198 1421 9,464,491 97,877,689
39,151,076
2033 14 18 276 1103 410 197 412 211 1508 10,043,602 107,921,292
43,168,517
2034 15 18 292 1170 435 209 437 223 1601 10,658,150 118,579,441
47,431,776
2035 16 19 310 1242 462 222 464 237 1699 11,310,302 129,889,744
51,955,897
2036 17 20 329 1318 490 235 492 252 1803 12,002,361 141,892,105
56,756,842
2037 18 21 349 1399 520 250 522 267 1913 12,736,769 154,628,874
61,851,550
2038 19 22 371 552 265 554 283 2030 1484 13,516,116 168,144,991
67,257,996
2039 20 23 393 586 281 588 301 2154 1575 14,343,154 182,488,145
72,995,258
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Following chart shows the overall ESAL’s contributions of various
classified
transport vehicles.
2.5.3 Summary of Design Parameters
The design of flexible pavement is based on the 10-15%soaked CBR
for subgradeat
95% MDD (AASHTO T-180) Further, the main design parameters of
pavement
structural layershave been determined through the
comprehensive
analysis.Following Tableshows the summary of design
parameters.
Table 8: Summary of Design Parameters
Design Factors Parameters/Values
Asphalt Concrete Course (Mr) 400,000 psi (0.42)
Aggregate Base Course (Mr) 28,000 psi (0.14)
Sub-base Course (Mr) 18,000 psi (0.12)
Sub-grade (Mr) 11,153-14457psi (CBR=10%-15%)
BUSES 1%
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2.5.4 Computation of Pavement Design and Layer Thicknesses
Required structural number (SN) based upon all design variables has
been
calculated by using followingASHTO design equation:
18 0
1094 0.4
SN
Where;
The estimated future traffic in terms of ESALs for the design
period , W18
The reliability level ,R
The roadbed soil resilient modulus ,MR
The design serviceability loss,ΔPSI=P0-Pt
The estimated future traffic in terms of ESALs for the design
period (Wt18)was30
million.The required structure number (SN) was5.37 against
10%sub-grade CBR
value;which has been fulfilled by providing adequate pavement
structure.Under
AASHTO design procedure the following equation provides the means
for
converting the structural number into actual thicknesses of
surfacing, base and
sub-base materials:
Where:
a1, a2&a3 = layer coefficients representative of surface, base
and sub-base
course respectively;
D1,D2&D3 = actual thicknesses (in inches) of surface, base and
sub-base courses
respectively;
m2&m3 = drainage coefficients for base and sub-base layers
respectively.
Theabove equation does not have a single unique solution. There are
many
combinations of layer thicknesses that can be adopted to achieve a
given
structural number. However, several design construction and
financial constraints
whichmay be applied to reduce the number of possible layer
thickness
combinations and to avoid the possibility of constructing an
impractical design.
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2.5.5 Pavement Design;Peshawar –Torkham Motorway
Following Tables show the results of pavement thickness calculation
from AASHTO
method for Peshawar – Torkham Motorway. The required Structure
Number
comes out to be 5.37 for 10 years for Pavement Design.
Table 9: Design Thickness of Pavement Structure against Sub-grade
CBR = 10%
PAVEMENT THICKNESS CALCULATION
INCHES CMS INCHES CMS
1 Asphalt Concrete Course = ACWC+ACBC = 9.31 23.646 8.27 24.00
3.97
2 Aggregate Base Course = ABC = 4.19 10.636 11.81 30.00 1.65
3 Granular Sub-base = GSB = 6.58 16.722 7.87 20.00 0.94
4 Subgrade (10% CBR) = SG = 11.81 30.00 0.00
SN provided with new pavement structure 6.57
SN provided = 6.57 > SN required 5.37 Hence OK
Based upon the required structural number following pavement
thickness has
been proposed for construction of Peshawar-Torkham Motorway.
Proposed Pavement Design for new Construction:
Asphaltic Concrete wearing Course = 50 mm
Asphaltic Concrete Base Course = 190 mm
Aggregate Base Course = 300 mm
Granular Sub-base = 200 mm
Sub-grade = 300 mm @ 10% CBR
2.5.6 Pavement Thickness Design Optimization
Effect thickness design is one of the most important aspects of
project design. The
pavement material, construction methods, and finished project
requirements
must be both practical to attain and clearly defined. The designer
ensured that the
plans, specifications and estimate clearly and unambiguously define
the
requirements. A flexible pavement structure consists of the
following layers – the
sub-base, base course, intermediate HMA course (Asphalt Concrete
Base Course)
and a surface course. The sub-bas consists of granular material –
gravel, crushed
stone, reclaimed material or a combination of these materials. The
thickness
design has been optimized keeping in view the quality borrow
sources available in
the vicinity of the project nearby achieving improved resilient
modulus of the
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underlying layers: top 30 cm of embankment fill (= 15% CBR),
quality materials of
GSB and GBC. Asphaltic base course layer thickness is optimized to
16 cm followed
by 5 cm of asphalt wearing course. The design meets the required
structural
number of 4.63 as the provided structural number is 5.52.
Table 10: Design Thickness of Pavement Structure against Sub-grade
CBR = 15%
PAVEMENT THICKNESS CALCULATION
INCHES CMS INCHES CMS
1 Asphalt Concrete Course = ACWC+ACBC = 9.31 23.646 7.48 21.00
3.47
2 Aggregate Base Course = ABC = 4.19 10.636 7.87 20.00 1.10
3 Granular Sub-base = GSB = 3.08 7.832 7.87 20.00 0.94
4 Subgrade (15% CBR) = SG = 11.81 30.00 0.00
SN provided with new pavement structure 5.52
SN provided = 5.52 > SN required 4.63 Hence OK
Optimized Pavement Design for new Construction:
Asphaltic Concrete wearing Course = 50 mm
Asphaltic Concrete Base Course = 160 mm
Aggregate Base Course = 200 mm
Granular Sub-base = 200 mm
2.6 Rigid Pavement Design
Jointed Plain Concrete Pavement is proposed for pavement design
(JPCP) which
uses contraction joints and Dowel bars for load transfer.
Different parameters used for the design of rigid pavement are
described in the
following paras. Following parameters have been used for the design
of the rigid
pavement:
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Modulus of Rupture required by the design procedure is the mean
value
determined after 28 days using third point loading (AASHTO T97,
ASTM C78).
Modulus of Rupture can also be derived from the two
equations:
i. Sc = 43.5 x Ec / 10^6 + 488.5
ii. Sc = 8x fc’^0.5 10xfc’^0.5
Effective Modulus of Sub Grade Reaction (k) calculated based upon
the sub-base
type, potential design thickness of sub-base, depth of rigid
foundation, roadbed
resilient modulus and sub-base modulus of resilience from the chart
given in the
ASHTO Design Guide for Pavement Structures.
Based upon these values Rigid Pavement has been designed using the
AASHTO
Guide for Pavement Design, 1993. Jointed Reinforced Concrete
Pavement (JRCP) is
proposed for construction of rigid pavement.
2.6.1 Modulus of Subgrade Reaction
Modulus of Subgrade Reaction (k) gives the support of the
underlying layers. For
the proposed designed CBR value of 15% for New Rigid pavement
design and
assuming the thickness of Sub-base as 5.5”, the k value calculated
using the
AASHTO Figure 3.3 is as follows:
Dsb = 5.5” (140 mm)
Mr = 14,000 psi (CBR of 15% for subgrade)
The resultant k value is taken as 650pci which is the Composite
Modulus of
Subgrade Reaction for construction of new pavement.For LOS (Loss of
Support)
values taken as 1 (Refer table 2.7), the Effective modulus of
Reaction Value comes
out to be 180pci taking into account the LOS factor.
2.6.2 PCC Elastic Modulus
For calculating the Elastic Modulus of PCC following equation is
used as
recommended by AASHTO (2.3.3):
Ec = 57,000 (fc’)^0.5
fc’ = PCC compressive strength in psi.
Using a value of 4000 psi for compressive strength of PCC, Ec
(Elastic Modulus of
PCC) comes out to be 3,604,997 psi.
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2.6.3 Load Transfer Coefficient
The load transfer coefficient (J) accounts for load transfer
efficiency. As a general
rule lower the J factor better load transfer. It is used on
concrete pavement
structure to transfer load across discontinuities such as joints or
cracks. A value of
3.2 is proposed for J.
2.6.4 PCC Modulus of Rupture
This is a measure of the PCC flexural strength. Modulus of Rupture
required by the
design procedure is the mean value determined after 28 days using
third point
loading (AASHTO T97, ASTM C78). Modulus of Rupture can also be
derived from
the two equations:
ii. Sc = 8x fc’^0.5 10xfc’^0.5
Equation (i) gives the value of 645 psi and equation 2 gives (with
a value of 9) 569
psi. Average of the two is 607 psi for the Modulus of Rupture.
However, based
upon the practical experience with the material a value of 590 psi
is proposed for
the pavement design.
2.6.5 Pavement Thickness Design
The thickness or depth of pavement is calculated using the
following equation as
recommended by AASHTO:
Log10W18= Zr*So+7.35*log10 (D+1)-0.06+ log10 {Pt-Po}/4.5-
1.5/1+1.624*10^7/(D+1)^8.46+(4.22-0.32pt)xlog10
{(Sc')(Cd)(D^0.75)-1.132/215.63(j)(D^0.75-18.42/(Ec/k)^0.25)
Using the various values calculated above the thickness of the slab
“D” comes out
to be 13.8” for the subject project road. The recommended pavement
design is as
follows:
Lean Concrete = 3.9” (100 mm)
Granular Sub-base = 5.5” (140 mm)
Subgrade = 11.81” (300 mm), CBR of 15%.
2.6.6 Slab Length and Reinforcement
JPCP is the most common type of rigid pavement. JPCP controls
cracks by dividing
the pavement up into individual slabs separated by contraction
joints. Slabs are
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typically one lane wide and between 3.7 m (12 ft.) and 6.1 m (20
ft.) long. JPCP
does not use any reinforcing steel but does use dowel bars and tie
bars.
Jointed plain concrete pavement uses contraction joints to control
cracking and
does not use any reinforcing steel. Transverse joint spacing is
selected such that
temperature and moisture stresses do not produce intermediate
cracking
between joints. This typically results in a spacing no longer than
about 6.1 m (20
ft.). Dowel bars are typically used at transverse joints to assist
in load transfer. Tie
bars are typically used at longitudinal joints. The proposed slab
length is 4.5 m
with a width of 3.65 m (one lane width). The width to length ratio
is 1.24 against
the requirement of 1.25. Following table gives major features of
the JPCP:
Major Features of Jointed Plain Concrete Pavement (JPCP)
Crack Control: Contraction joints, both transverse and
longitudinal
Joint Spacing: Typically between 3.7 m (12 ft.) and 6.1 m (20 ft.).
Due to the
nature of concrete, slabs longer than about 6.1 m (20 ft.)
will
usually crack in the middle. Depending upon environment
and materials slabs shorter than this may also crack in the
middle.
Load Transfer: Aggregate interlock and dowel bars. For low-volume
roads
aggregate interlock is often adequate. However, high-volume
roads generally require dowel bars in each transverse joint
to
prevent excessive faulting.
2.6.7 Design of Tie Bars
Tie bars are either deformed steel bars or connectors used to hold
the faces of
abutting slabs in contact (AASHTO, 1993). Although they may provide
some
minimal amount of load transfer, they are not designed to act as
load transfer
devices and should not be used as such (AASHTO, 1993). Tie bars are
typically
used at longitudinal joints or between an edge joint and a curb or
shoulder.
Typically, tie bars are about 12.5 mm (0.5 inches) in diameter and
between 0.6 to
1.0 m (24 to 40 inches long). We have proposed the diameter of tie
bars as 25mm
and length of tie bars as 35 inches.
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2.6.8 Design of Dowel Bars
Dowel bars are short steel bars that provide a mechanical
connection between
slabs without restricting horizontal joint movement. They increase
load transfer
efficiency by allowing the leave slab to assume some of the load
before the load is
actually over it. This reduces joint deflection and stress in the
approach and leave
slabs.
Dowel bars are used for Transverse Joints. Dowel Bar spacing is
designed for 12
inches spacing and dowel bar length is 18 inches. The diameter of
the dowel bar is
taken as slab thickness (12”) multiplied by 1/8 (AASHTO 2.4.2).
Thus for our case
the diameter for the dowel bar comes out to be 1.5”.
It is proposed that 36mm bar to be used for the Dowel Bar. These
are provided at
a distance of 12” on the transverse joint thus would also be used
as contraction
joint.
Dowel bars are typically 32 to 38 mm (1.25 to 1.5 inches) in
diameter, 460 mm (18
inches) long and spaced 305 mm (12 inches) apart. Specific
locations and numbers
vary. In order to prevent corrosion, dowel bars are either coated
with stainless
steel or epoxy. Dowel bars are usually inserted at mid-slab depth
and coated with
a bond-breaking substance to prevent bonding to the PCC. Thus, the
dowels help
transfer load but allow adjacent slabs to expand and contract
independent of one
another. Following figure shows typical dowel bar locations at a
transverse
construction joint.
2.6.9 Contraction Joint
A contraction joint is a sawed, formed, or tooled groove in a
concrete slab that
creates a weakened vertical plane. It regulates the location of the
cracking caused
by dimensional changes in the slab. Unregulated cracks can grow and
result in an
unacceptably rough surface as well as water infiltration into the
base, sub-base
and subgrade, which can enable other types of pavement
distress.
Contraction joints are the most common type of joint in concrete
pavements, thus
the generic term "joint" generally refers to a contraction
joint.
Contraction joints are chiefly defined by their spacing and their
method of load
transfer. They are generally between 1/4 - 1/3 the depth of the
slab and typically
spaced every 3.1 - 15 m (12 - 50 ft.) with thinner slabs having
shorter spacing
Some use a semi-random joint spacing pattern to minimize their
resonant effect
on vehicles. These patterns typically use a repeating sequence of
joint spacing (for
example: 2.7 m (9 ft.) then 3.0 m (10 ft.) then 4.3 m (14 ft.) then
4.0 m (13 ft.)).
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Transverse contraction joints can be cut at right angles to the
direction of traffic
flow or at an angle (called a "skewed joint",). Skewed joints are
cut at obtuse
angles to the direction of traffic flow to help with load transfer.
If the joint is
properly skewed, the left wheel of each axle will cross onto the
leave slab first and
only one wheel will cross the joint at a time, which results in
lower load transfer
stresses.
2.6.10 Expansion Joint
An expansion joint is placed at a specific location to allow the
pavement to expand
without damaging adjacent structures or the pavement itself. Up
until the 1950s,
it was common practice in the U.S. to use plain, jointed slabs with
both
contraction and expansion joints (Sutherland, 1956). However,
expansion joint
are not typically used today because their progressive closure
tends to cause
contraction joints to progressively open (Sutherland, 1956).
Progressive or even
large seasonal contraction joint openings cause a loss of load
transfer particularly
so for joints without dowel bars.
2.6.11Construction Joint
A construction joint is a joint between slabs that results when
concrete is placed at
different times. This type of joint can be further broken down into
transverse and
longitudinal construction joints. Longitudinal construction joints
also allow slab
warping without appreciable separation or cracking of the
slabs.
The joint sealant depth should be at least 1 inch for both
Longitudinal and
Transverse joints. Joints shall be sealed before the pavement is
opened to traffic
or to use by construction equipment, and as soon after completion
of the sawing
as is feasible. Just prior to sealing, each joint shall be
thoroughly cleaned of all
foreign material, using approved equipment, and the joint faces
shall be clean and
surface dry when the seal is applied.
Transverse contraction joints shall be sealed with seals meeting
the requirements
of Preformed Elastomeric Compression Joint Seal for Concrete.
AASHTO M 220.
The lubricants for installation of preformed compression seals
shall be as
recommended by the seal manufacturer.
The seals shall be installed by suitable tools using an approved
lubricant-adhesive
which shall cover both sides of the sealer. The seals shall be
installed in a
substantially full compressed condition and shall at all times be
below the level of
the pavement surface by approximately 6 mm (1/4 inch). The seals
shall be in one
piece without field or factory splice between longitudinal joint
and edge of
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payment or between longitudinal joints of multilane pavement. The
elongation of
the seals during installation shall not exceed 5 percent as
determined by length
measurement marks. Expansion joints shall be sealed with material
conforming to
Hot Applied Crack and Joint SealerASTM D 3405.
2.6 Typical Pavement Cross Section
Typical cross sections has been developed for the new flexible
pavement of
Peshawar – Torkham Motorway and attached as Annexure-D.
2.7 Pavement Drainage Design
Drainage design is one of the most important elements in design of
the pavement
structure. The main aim of drainage design of pavements is to
prevent the
prolonged saturation/exposure of any of the pavement layers to high
levels of
moisture. Broadly, three approaches can be adopted to control
moisture related
problems in pavements:
i. Seal the pavement such that water does not infiltrate the
pavement layers;
ii. Use materials that are insensitive to moisture changes,
and
iii. Provide adequate drainage such that any moisture (surface and
sub-
surface) can be drained-off efficiently.
These approaches are the basis of our design approach for the
drainage design of
pavement for the subject area. Moisture in roadbed and the pavement
structure
can come from any sources. The water may seep upward by capillary
action from a
high groundwater table, or it may flow literally from the pavement
edges and the
shoulder ditches.
Water vapor and capillary movement are also responsible for water
accumulating
beneath a pavement structure. The water in a pavement can also
result from
infiltration through the pavement surface. Joints, cracks, shoulder
edges and
various defects in the surface, present easy access paths for the
water. In frost
susceptible soils (in freezing areas) melting ice-lenses contribute
a significant
portion of the free water during the spring freeze-thaw
period.
In short, for the project pavement drainage design, the effect of
free subsoil water
and the water infiltration are considered in the design. The
drainage design of
pavements can be dealt in two parts:
1. Surface drainage design
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2. Subsurface drainage design
2.7.1 Surface Drainage Design
1. Surface material permeability
This is simple most important cause of moisture accumulation under
the
pavement in the subgrade. The effect of infiltration of surface
water has been
directly related to the amount of precipitation and the pavement
condition3. In
general, the permeability of flexible pavements decreases with the
pavement life
as the traffic seals the porous surface. The permeability (k) of
flexible pavements is
generally selected at an approximate value of 0.5 in/hr.
2. Transverse Pavement Slope
The project road has been designed with a cross fall along all the
tangent sections
of road to shed the surface water on both sides of the road, with
the exception of
the curves, where super-elevation has been introduced due to the
dictates of the
geometric design, and water is shed to the inside of the curve and
proper drainage
pits been provided with grating. The cross fall is 2%, and the
cross fall in the curves
varies with the curvature. The shoulders have been designed at a 4%
cross-slope
in the tangent sections. In the curves, the shoulder cross-slopes
are (-) 4% on the
outer side of the curve, and on the inside of the curve.
If super-elevation is 4% or less, then the cross-slope of the
shoulder is 4%, and:
If super-elevation is more than 4%, then the cross slope of the
shoulder is the same as
the super-elevation of the roadway.
3. Transverse Pavement Slope
The longitudinal grades are dictated by design criteria for vehicle
speed, sight
distances, and drainage. For this road, maximum gradients of 6% are
allowed,
primarily to lower the project costs by controlling excessive cut
and fill. So, the
surface drainage design by easing the longitudinal grades is not
the controlling
factor for finalizing the road gradients.
4. Runoff Ditches and Water Chutes
3Dempsey, B. J., and Q. U. Robnett. Influence of precipitation,
Joints, and sealing on pavement Drainage.
Record No. 705.Transportation Research Board, 1979.
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Runoff ditches have been provided on both sides of the road in the
cut sections/reaches
for the collection of water from surface of road and to drain it in
nearby cross drainage
structure.
The depth and shape of the drainage (or runoff) ditches should be
based on the
following criteria to enhance removal of water away from the
pavement structure:
The bottom of the ditch should be at the same or lower elevation as
that of the
subgrade:
The side slopes should be 2:1 (H:V), or flatter, for safety and
erosion issues;
The longitudinal slopes should prevent silting;
The longitudinal slopes should prevent erosion of the ditch bottom
(for fine sand or silt
bottom, the velocity should not exceed 1ft/sec; slightly higher
velocities can be
tolerated in cohesive clayey soils);
Minimizing excavation, construction, and maintenance costs.
Lined drain has been proposed throughout the length of cut sections
for Peshawar-Torkham
Motorway so that cleaning of the drain shall be easy. Complete list
of lined drain is attached
as Annexure-E.
2.7.2 Subsurface Drainage Design
The subsurface drainage design for the pavement structure of
project road is
based on the following criteria.
1. The pavement system, including shoulders and adjacent areas
should be
designed and maintained as impervious as possible to minimize
infiltration of
surface and ground water into critical areas;
2. The drainage facility should be designed with a water removing
capability such
that infiltrating water can be removed in a very short
period;
3. The drainage system should be designed as a structural member of
the
pavement structure and must not decrease the performance of the
pavement
or require exceptional measures to compensate for material
problems.
Keeping in view the first criteria, that demands for infiltration
calculations for this
high priority road, which has to be based on judgment alone. As
such in-depth
infiltration calculations for net water inflow4 are not
available.
For the project road, the soils found along the road are apparently
permeable and
water table is not high therefore we foresee no major sub surface
drainage
problem. The design philosophy is to drain any infiltrating water
(from the upper
4 Net water inflow = design infiltration rate+the design inflow
rate+the design inflow rate from artesian
flow+quantity of water from ice-lense melt-vertical outflow.
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pavement layers) as soon as possible so that it does not stay under
the pavement
long enough to saturate the sub-grade. This has been accomplished
by:
Providing transverse slope in the sub-grade of 2% cross fall under
the
pavement, and 4% cross-slope under the shoulders;
Properly/Well graded aggregate base course and sub-base has been
provided;
Provision of day lighted aggregate base course and sub-base under
the
shoulders;
Provision of treated shoulders.
Pavement Design Report Annexure-A
M/s ACC in association with M/s SAMBO, M/s ACE-TES & M/s Assign
Page 27
Annexure A: Soil Investigation Testing Summary for Proposed
Alignment of Motorway
P it
N o
(Kms) 2" 1"1/2 1" 3/4" 3/8" No.4 No.10 No.40 No.20
0 LL PL PI
95% 90%
1 3+000 100 100 66.17 52.39 28.52 18.72 12.06 6.81 5.01 28.62 19.19
9.4 A-2-4 GW- GC
2.247 7.0
2 8+100 100 100 100.0 100.0 68.51 36.19 15.53 4.13 2.48 29.35 22.73
6.6 A-1-a GP 2.214 7.6 41.0 25.0 5.3
3 13+050 100 100 100.0 100.0 60.77 34.50 15.17 5.08 3.59 30.89
22.89 8.0 A-2-4 GP 2.202 7.4 56.0 34.8 11.3
4 17+800 100 100 75.09 68.15 36.64 27.56 19.44 10.91 7.99 33.82
22.91 10.9 A-2-6 GW- GC
2.213 6.7 33.5 22.2 11.2
5 24+520 100 87.71 78.39 74.52 46.46 30.45 19.36 7.26 3.18 NON
PLASTIC A-1-a GP 2.277 6.6
6 28+000 100 81.15 75.94 61.78 47.53 42.43 39.28 34.83 31.68 31.71
23.38 8.3 A-2-4 GC 2.080 9.2
7 33+000 100 76.37 74.01 68.12 54.90 48.59 44.14 39.99 38.09 31.06
20.75 10.3 A-4 GC 2.122 8.8
8 38+300 100 100 100.0 100.0 78.87 68.48 62.67 59.03 56.19 29.25
21.14 8.11 A-4 CL 2.077 9.9 21.7 13.0 2.6
9 42+600 100 77.51 66.01 50.79 44.32 37.55 32.15 25.74 21.58 29.38
21.09 8.29 A-2-4 GC 2.163 8.8 47.0 24.3 9.5
10 46+600 100 100 94.13 84.62 64.73 55.24 47.60 39.07 32.13 23.96
19.71 4.25 A-2-4 GM /GC
2.201 6.8
Pavement Design Report Annexure-B
M/s ACC in association with M/s SAMBO, M/s ACE-TES & M/s Assign
Page 28
Annexure B: Material Testing Summaries of Borrow Material &
Aggregate Quarry Sources
P it
N o
(Kms) 2" 1"1/2 1" 3/4" 3/8" No.4 No.10 No.40 No.20
0 LL PL PI
95% 90%
1 6+000 100 92.96 80 69.08 54.02 38.63 24.64 8.72 3.81 NON
PLASTIC
NON PLASTIC
NON PLASTIC
A-1-a GP 2.260 6.8 43.3 31.0 16.2
2 10+500 100 87.13 74.47 67.64 46.95 34.39 22.73 8.23 3.88 NON
PLASTIC
NON PLASTIC
NON PLASTIC
A-1-a GP 2.210 6.6 48.2 23.7 10.5
3 27+500 100 89.36 77.32 57.11 27.28 18.57 13.59 6.61 3.34 NON
PLASTIC
NON PLASTIC
NON PLASTIC
A-1-a GP 2.330 5.4 69.8 50.7 23.0
4 38+000 100 100 92.82 86.15 51.31 29.84 24.83 22.67 21.58 29.72
21.43 8.29 A-2-4 GC 2.261 7.0 44.5 31.3 17.5
5 46+700 100 100 88.92 66.24 48.35 33.11 23.74 11.34 5.83 NON
PLASTIC A-1-a G
W - G M
Pavement Design Report (Revised)
M/s ACC in association with M/s SAMBO, M/s ACE-TES & M/s Assign
Page 29
Material Testing Summaries of Borrow Material & Aggregate
Quarry Sources
D e
sc ri
p ti
o n
Locatio n
Los Angeles Abrasio
Agg 1.5" 100 100 98.63 24.3 0.47 0.25 0.14 24.10
Filler 100 97.7 63.8 19.7 8.6
Agg 1.5" Crusher
Filler 100 93.5 36.5 5.1 4.1
SAND Lawranc
Pavement Design Report Annexure-C
M/s ACC in association with M/s SAMBO, M/s ACE-TES & M/s Assign
Page 30
Annexure C: Average Annual Daily Traffic (AADT)for Peshawar –
Torkham Motorway
Year
Vehicle
Type
Car
Jeep
Wagons
Coaster
Pickup
ADT AADT 2-Axle 3-Axle 3-Axle 4-Axle 5 -Axle 6 -Axle
AGR (%) 4.74 4.74 4.74 4.74 6.78 6.78 6.78 6.78 6.78 6.78
Base Year 2017 5019 2280 7 57 361 136 65 135 70 474 8,604
3,140,460
Const. Period
2018 5288 2402 7 61 386 146 70 145 75 507 9,087 3,316,748
2019 5539 2516 8 65 413 155 74 154 80 542 9,546 3,484,307
1 2020 6828 2883 10 122 486 181 87 182 93 665 11,538
4,211,198
2 2021 7134 3013 11 130 518 193 93 194 99 709 12,092
4,413,580
3 2022 7454 3147 11 139 552 205 99 206 105 755 12,674
4,625,927
4 2023 7788 3288 12 148 588 219 105 220 112 805 13,284
4,848,745
5 2024 8137 3436 12 158 627 233 112 234 120 858 13,925
5,082,565
6 2025 8501 3590 13 168 668 248 119 249 127 914 14,597
5,327,948
7 2026 8873 3747 13 178 710 264 127 265 135 972 15,284
5,578,528
8 2027 9260 3910 14 190 755 281 135 282 144 1033 16,003
5,841,181
9 2028 9665 4081 14 202 802 298 143 300 153 1098 16,758
6,116,505
10 2029 10087 4260 15 215 853 317 152 319 163 1168 17,548
6,405,128
11 2030 10528 4446 16 228 907 337 162 339 173 1242 18,377
6,707,713
12 2031 10975 4634 16 242 963 358 172 360 184 1318 19,220
7,015,368
13 2032 11440 4831 17 257 1021 380 182 382 195 1398 20,103
7,337,490
14 2033 11925 5035 18 273 1084 403 194 405 207 1484 21,027
7,674,780
15 2034 12430 5249 18 289 1150 428 205 430 220 1575 21,994
8,027,974
16 2035 12958 5472 19 307 1221 454 218 456 233 1671 23,008
8,397,843
17 2036 13507 5704 20 326 1295 482 231 484 247 1773 24,069
8,785,199
18 2037 14080 5945 21 346 1375 511 245 514 262 1882 25,181
9,190,894
19 2038 14677 6197 22 367 1459 543 261 545 278 1997 26,345
9,615,822
20 2039 15299 6460 23 389 1548 576 276 578 296 2119 27,564
10,060,923
Pavement Design Report Annexure-D
M/s ACC in association with M/s SAMBO, M/s ACE-TES & M/s Assign
Page 31
Annexure D: Typical Pavement Cross Sections
Pavement Design Report (Revised) Annexure-D
M/s ACC in association with M/s SAMBO, M/s ACE-TES & M/s Assign
Page 32
Pavement Design Report (Revised) Annexure-D
M/s ACC in association with M/s SAMBO, M/s ACE-TES & M/s Assign
Page 33
Pavement Design Report Annexure-E
M/s ACC in association with M/s SAMBO, M/s ACE-TES & M/s Assign
Page 34
Annexure E: List of Lined Drain & Brest Wall
List of Lined Drain and Breast Wall
Sr. No.
Chainage (Km) Length Road Side
From To (m) (L/R/B) From To (m) (L/R/B)
1 6+340 6+920 580 Both Side 91 27+370 27+440 70 Left Side
2 7+200 7+380 180 Both Side 92 27+560 27+720 160 Left Side
3 7+380 7+390 10 Left Side 93 27+870 28+120 250 Both Side
4 7+460 7+490 30 Left Side 94 28+120 28+220 100 Left Side
5 7+490 8+440 950 Both Side 95 28+220 28+580 360 Both Side
6 8+440 8+500 60 Left Side 96 28+580 28+660 80 Left Side
7 8+700 8+790 90 Both Side 97 28+740 28+840 100 Both Side
8 8+920 8+980 60 Right Side 98 28+910 29+260 350 Left Side
9 8+980 9+020 40 Both Side 99 30+080 30+160 80 Left Side
10 9+020 9+180 160 Left Side 100 30+160 30+300 140 Both Side
11 9+260 9+550 290 Both Side 101 30+300 30+340 40 Left Side
12 9+685 9+720 35 Left Side 102 30+500 30+540 40 Left Side
13 9+860 9+980 120 Left Side 103 30+540 30+580 40 Both Side
14 10+100 10+120 20 Left Side 104 30+580 30+740 160 Left Side
15 10+240 10+590 350 Both Side 105 30+840 31+010 170 Left
Side
16 10+590 10+640 50 Left Side 106 31+010 31+120 110 Both Side
17 10+720 11+040 320 Both Side 107 31+120 31+380 260 Left
Side
18 11+150 11+370 220 Both Side 108 31+500 31+680 180 Left
Side
19 11+370 11+550 180 Left Side 109 31+680 31+780 100 Both
Side
20 11+550 11+660 110 Both Side 110 31+780 32+000 220 Left
Side
21 11+660 11+780 120 Left Side 111 32+000 32+060 60 Both Side
22 11+940 12+220 280 Left Side 112 32+060 32+160 100 Left
Side
23 12+220 12+340 120 Both Side 113 32+160 32+300 140 Both
Side
24 12+340 12+420 80 Left Side 114 32+300 32+320 20 Left Side
25 12+420 12+910 490 Both Side 115 32+580 32+740 160 Left
Side
26 12+910 12+960 50 Left Side 116 33+240 33+280 40 Left Side
27 12+960 13+000 40 Both Side 117 33+280 33+440 160 Both Side
28 13+000 13+040 40 Left Side 118 33+440 33+500 60 Left Side
29 13+040 13+090 50 Both Side 119 33+700 33+750 50 Both Side
30 13+090 13+120 30 Left Side 120 33+750 33+920 170 Left Side
31 13+120 13+200 80 Both Side 121 34+000 34+360 360 Left Side
32 13+260 13+340 80 Both Side 122 34+500 34+580 80 Left Side
33 13+380 13+440 60 Left Side 123 34+580 34+620 40 Both Side
34 13+530 13+620 90 Both Side 124 34+620 34+680 60 Left Side
35 13+620 13+640 20 Left Side 125 34+680 34+920 240 Both Side
36 13+740 13+820 80 Left Side 126 35+120 35+260 140 Both Side
37 13+940 13+980 40 Left Side 127 35+260 35+300 40 Left Side
Pavement Design Report (Revised) Annexure-E
M/s ACC in association with M/s SAMBO, M/s ACE-TES & M/s Assign
Page 35
List of Lined Drain and Breast Wall
Sr. No.
Chainage (Km) Length Road Side
From To (m) (L/R/B) From To (m) (L/R/B)
38 13+980 14+810 830 Both Side 128 35+460 35+520 60 Left Side
39 14+900 14+940 40 Left Side 129 35+520 35+640 120 Both Side
40 14+940 14+980 40 Both Side 130 35+640 35+780 140 Left Side
41 14+980 15+000 20 Left Side 131 35+780 36+000 220 Both Side
42 15+000 15+100 100 Both Side 132 36+000 36+020 20 Left Side
43 15+290 15+940 650 Both Side 133 36+080 36+330 250 Both
Side
44 15+940 16+160 220 Right Side 134 36+460 36+480 20 Left
Side
45 16+220 16+240 20 Both Side 135 36+480 36+520 40 Both Side
46 16+240 16+470 230 Right Side 136 36+520 36+680 160 Left
Side
47 16+580 16+620 40 Both Side 137 36+680 36+780 100 Both Side
48 16+860 16+910 50 Left Side 138 36+780 36+940 160 Left Side
49 16+910 17+000 90 Both Side 139 36+940 36+980 40 Both Side
50 17+000 17+040 40 Left Side 140 36+980 37+010 30 Left Side
51 17+120 17+180 60 Left Side 141 37+030 37+080 50 Left Side
52 17+300 17+390 90 Left Side 142 37+080 37+110 30 Both Side
53 17+390 17+420 30 Both Side 143 37+140 37+250 110 Left Side
54 17+420 17+460 40 Left Side 144 37+250 37+300 50 Both Side
55 18+020 18+250 230 Both Side 145 37+300 37+420 120 Left
Side
56 18+250 18+280 30 Right Side 146 37+420 38+100 680 Both
Side
57 18+280 18+460 180 Both Side 147 38+640 38+660 20 Right
Side
58 18+460 18+520 60 Right Side 148 38+660 39+620 960 Both
Side
59 18+610 18+660 50 Both Side 149 39+760 39+940 180 Left Side
60 18+660 18+680 20 Right Side 150 39+940 40+120 180 Both
Side
61 18+740 18+820 80 Right Side 151 40+120 40+180 60 Left Side
62 18+820 19+340 520 Both Side 152 40+250 40+430 180 Both
Side
63 19+340 19+400 60 Right Side 153 40+430 40+470 40 Left Side
64 20+700 20+800 100 Both Side 154 40+600 40+660 60 Left Side
65 21+050 21+080 30 Right Side 155 40+660 41+330 670 Both
Side
66 21+900 21+960 60 Left Side 156 41+330 41+390 60 Left Side
67 21+960 22+170 210 Both Side 157 41+480 42+400 920 Both
Side
68 22+170 22+400 230 Left Side 158 42+500 42+660 160 Right
Side
69 22+400 22+500 100 Both Side 159 42+710 42+800 90 Both Side
70 22+500 22+520 20 Left Side 160 42+800 42+840 40 Right Side
71 22+800 23+600 800 Both Side 161 42+840 43+200 360 Both
Side
72 23+620 24+140 520 Left Side 162 43+260 43+640 380 Both
Side
73 24+400 24+540 140 Left Side 163 43+720 43+835 115 Right
Side
74 25+680 25+740 60 Left Side 164 43+870 43+900 30 Right Side
75 25+740 26+070 330 Both Side 165 43+900 44+360 460 Both
Side
Pavement Design Report (Revised) Annexure-E
M/s ACC in association with M/s SAMBO, M/s ACE-TES & M/s Assign
Page 36
List of Lined Drain and Breast Wall
Sr. No.
Chainage (Km) Length Road Side
From To (m) (L/R/B) From To (m) (L/R/B)
76 26+120 26+200 80 Both Side 166 44+480 44+730 250 Both Side
77 26+340 26+380 40 Left Side 167 45+280 45+340 60 Left Side
78 26+410 26+560 150 Left Side 168 45+390 45+410 20 Both Side
79 26+680 26+900 220 Left Side 169 45+420 45+880 460 Left
Side
80 Equation: 26+905 BK = 26+100 AH 170 45+880
81 26+100 26+200 100 Left Side 171 46+500 46+640 140 Right
Side
82 26+240 26+280 40 Left Side 172 46+640 46+720 80 Both Side
83 26+280 26+400 120 Both Side 173 46+720 46+960 240 Right
Side
84 26+400 26+440 40 Left Side
85 26+490 26+560 70 Left Side
86 26+560 26+600 40 Both Side
87 26+740 26+820 80 Left Side
88 26+880 26+930 50 Left Side
89 27+080 27+180 100 Left Side
90 27+300 27+370 70 Both Side
CHAPTER 1 - INTRODUCTION
CHAPTER 2 – PAVEMENT EVALUATION AND DESIGN
2.1 Design Criteria
2.2.1 Description of Field and Laboratory Work
2.2.2 Borrow Sources
2.2.3 Quarry Sources
2.4.6 Serviceability
2.5.4 Computation of Pavement Design and Layer Thicknesses
2.5.5 Pavement Design;Peshawar –Torkham Motorway
2.5.6 Pavement Thickness Design Optimization
2.6 Rigid Pavement Design
2.6.2 PCC Elastic Modulus
2.6.3 Load Transfer Coefficient
2.6.5 Pavement Thickness Design
2.6.9 Contraction Joint
2.6.10 Expansion Joint
2.7 Pavement Drainage Design
2.7.1 Surface Drainage Design
2.7.2 Subsurface Drainage Design
Annexure A: Soil Investigation Testing Summary for Proposed
Alignment of Motorway
Annexure B: Material Testing Summaries of Borrow Material &
Aggregate Quarry Sources
Material Testing Summaries of Borrow Material & Aggregate
Quarry Sources
Annexure C: Average Annual Daily Traffic (AADT)for Peshawar –
Torkham Motorway
Annexure D: Typical Pavement Cross Sections
Annexure E: List of Lined Drain & Brest Wall