Highway Engineering PPresentation-elmer2.ppt

Highway
Highway
Engineering
Engineering
Engr. Elmer C. Agon
Engr. Elmer C. Agon

Course Outline
Course Outline
Chapter I
Chapter I. Introduction to Highway Engineering
. Introduction to Highway Engineering
Chapter II
Chapter II. Subgrade, Sub base and Unbound
. Subgrade, Sub base and Unbound
Pavement Materials. Soil
Classification and Compaction
Chapter III
Chapter III. Aggregates
. Aggregates
Chapter IV
Chapter IV. Bituminous Materials
. Bituminous Materials
Chapter V
Chapter V. Stresses in Pavements
. Stresses in Pavements
Chapter VI
Chapter VI. Traffic Loading and Volume
. Traffic Loading and Volume
Chapter VII
Chapter VII. Structural Design of Pavements
. Structural Design of Pavements

Grade Allocation
Grade Allocation
Midterm Exam
Midterm Exam = 25%
= 25%
Final Exam
Final Exam = 40%
= 40%
Laboratory
Laboratory = 25%
= 25%
Continuous assessment
Continuous assessment = 10%
= 10%

CHAPTER I
CHAPTER I
Introduction to Highway Engineering
Introduction to Highway Engineering

Introduction
Introduction
Highway engineering is a
Highway engineering is a
specialization of civil engineering
specialization of civil engineering
profession which normally engaged in the
profession which normally engaged in the
design and construction of roadways,
design and construction of roadways,
streets, railways and highway
streets, railways and highway
architectures.
architectures.

Highway Engineering
Highway Engineering
It is the process of design and
It is the process of design and
construction of efficient and safe
construction of efficient and safe
highways and roads. Standards use in
highways and roads. Standards use in
states includes AASHTO as the standard
states includes AASHTO as the standard
for policy in geometric design.
for policy in geometric design.

Pavement Engineering
Pavement Engineering
A branch of civil engineering that
A branch of civil engineering that
uses engineering techniques to design
uses engineering techniques to design
and maintain flexible and rigid payments.
and maintain flexible and rigid payments.
This includes streets and highways and
This includes streets and highways and
involves knowledge of soils, hydraulics
involves knowledge of soils, hydraulics
and material properties.
and material properties.

Flexible Pavement
Flexible Pavement
It is normally called asphalt
It is normally called asphalt
pavement in a layman’s view. It range
pavement in a layman’s view. It range
from a sud grade roadway to a well
from a sud grade roadway to a well
constructed asphalt concrete.
constructed asphalt concrete.
Flexible pavement
Base course
Sub base course
Subgrade

Types of Flexible
Types of Flexible
pavement
pavement
Sub grade Roads
Sub grade Roads
 Gravel Roads
Gravel Roads
 Surface Treatment
Surface Treatment
 Concrete Asphalt
Concrete Asphalt

Rigid Pavements
Rigid Pavements
It is an all-weathered pavement
It is an all-weathered pavement
which is normally constructed using
which is normally constructed using
Portland concrete.
Portland concrete.
Rigid Pavement
Base course
Sub grade

Types of Rigid Pavement
Types of Rigid Pavement
 JPCP- Jointed Plain Concrete Pavement
JPCP- Jointed Plain Concrete Pavement
 JRCP- Jointed Reinforced Concrete
JRCP- Jointed Reinforced Concrete
Pavement
Pavement
 CRCP- Continuous Reinforced Concrete
CRCP- Continuous Reinforced Concrete
Pavement
Pavement
 PCP- Pre stressed Concrete Pavement
PCP- Pre stressed Concrete Pavement

Composite Pavement
Composite Pavement
It is a combination of flexible and
It is a combination of flexible and
rigid pavement. It is normally constructed
rigid pavement. It is normally constructed
in a heavily trafficked road.
in a heavily trafficked road.

Comparison of F and R
Comparison of F and R
Pavement
Pavement
 The manner of load transfer
The manner of load transfer
 Design precision
Design precision
 Design life
Design life
 Maintenance requirement
Maintenance requirement
 Initial cost
Initial cost
 Suitability for stage construction
Suitability for stage construction
 Surface characteristics
Surface characteristics
 Permeability
Permeability
 Traffic dislocation during construction
Traffic dislocation during construction

CHAPTER II
CHAPTER II
Subgrade, Sub base and Unbound
Subgrade, Sub base and Unbound

Sub-grade
Sub-grade
These are commonly compacted
These are commonly compacted
before construction of pavement and are
before construction of pavement and are
sometimes stabilized by the addition of
sometimes stabilized by the addition of
asphalt, soil cement, Portland cement or
asphalt, soil cement, Portland cement or
lime.
lime.

Two processes of
Two processes of
preparation
preparation
 Sub-grade formation
Sub-grade formation
 Reduction to level
Reduction to level

Origin and Formation of
Origin and Formation of
Soil
Soil
Soil can be defined from the civil
Soil can be defined from the civil
engineering point of view as a loose
engineering point of view as a loose
mass of mineral and organic materials
mass of mineral and organic materials
that covers the solid crust of granitic and
that covers the solid crust of granitic and
basaltic rocks of the earth.
basaltic rocks of the earth.

Basic types of soil
Basic types of soil
Soil
Soil Grain Size
Grain Size Grain Shape
Grain Shape Soil Group
Soil Group
Gravel
Gravel Over 5 mm
Over 5 mm Spherical and
Spherical and
Cubical
Cubical
Granular
Granular
Sand
Sand From 5 mm to
From 5 mm to
the smallest
the smallest
visible particle
visible particle
Spherical and
Spherical and
Cubical
Cubical
Granular
Granular
Silt
Silt Particle not
Particle not
visible to eye
visible to eye
Spherical and
Spherical and
Cubical
Cubical
Granular
Granular
Clay
Clay Smaller than silt
Smaller than silt Flat, plate-
Flat, plate-
shaped grain
shaped grain
Cohesive
Cohesive

Soil Classification
Soil Classification
1.
1. UNIFIED SYSTEM
UNIFIED SYSTEM
The first letter indicates the main soil
The first letter indicates the main soil
types and the second modifies the first.
types and the second modifies the first.

Unified- Soil Classification
Unified- Soil Classification
First Letter
First Letter
Symbol Description
Symbol Description
G
G Gravel
Gravel
S
S Sand
Sand
M
M Silt
Silt
C
C Clay
Clay
O
O Organic
Organic
Pt
Pt Peat
Peat
Second Letter
Second Letter
Symbol
Symbol Description
Description
W
W Well-graded
Well-graded
P
P Poorly-graded
Poorly-graded
N
N Silty Fines
Silty Fines
C
C Clayey Fines
Clayey Fines
H
H High Plasticity
High Plasticity
L
L Low Plasticity
Low Plasticity

Unified Cont…..
Unified Cont…..
Three General Areas
Three General Areas
1.
1. Coarse grained soil
Coarse grained soil
2.
2. Fine grained soil
Fine grained soil
3.
3. Peaty soil
Peaty soil

Highway Engineering PPresentation-elmer2.ppt

Sample Problems
Sample Problems
1.
1. Following are the results of a sieve analysis on granular soil.
Following are the results of a sieve analysis on granular soil.
Complete the calculation for the grain size distribution curve.
Complete the calculation for the grain size distribution curve.
Calculate the percentage of gravel, sand and fines.
Calculate the percentage of gravel, sand and fines.
Sieve
Sieve Mass Retained (g)
Mass Retained (g)
12.5mm
12.5mm 0
0
9.5mm
9.5mm 74.5
74.5
4.75mm
4.75mm 217.1
217.1
2.36mm
2.36mm 192.3
192.3
1.18mm
1.18mm 75.8
75.8
0.3mm
0.3mm 116.9
116.9
.075mm
.075mm 83.2
83.2
Pan
Pan 47.4
47.4

Sample Problems
Sample Problems
2. Determine the soil classification of the given grain size
2. Determine the soil classification of the given grain size
distribution using unified soil classification system.
distribution using unified soil classification system.
Passes (mm)
Passes (mm) %
%
38
38 100
100
19
19 90
90
9.5
9.5 77
77
4.75
4.75 53
53
0.425
0.425 33
33
0.075
0.075 20
20
w
w l
l 48
48
w
w p
p 31
31

Sample Problems
Sample Problems
3. Determine the soil classification of the given
grain size distribution using unified soil
classification system.
Passes (mm)
Passes (mm) %
%
9.5
9.5 100
100
4.75
4.75 60
60
0.425
0.425 30
30
0.15
0.15 10
10
0.075
0.075 4
4

Sample Problems
Sample Problems
4. Determine the soil classification of the
4. Determine the soil classification of the
given grain size distribution using unified
given grain size distribution using unified
soil classification system.
soil classification system.
Passing .075
Passing .075 80%
80%
w
w l
l =65%
=65%
Ip=42%
Ip=42%

Sample Problems
Sample Problems
Passes (mm)
Passes (mm) %
%
4.75
4.75 88
88
0.425
0.42528
28
0.075
0.07590
90
w
w p
p 20
20
w
w l
l 31
31

The AASHTO
The AASHTO
Classification System
1. Soil Classified as A-1-a, A-1-b, A-2-4
1. Soil Classified as A-1-a, A-1-b, A-2-4
and A-3 and be satisfactorily as sub-
and A-3 and be satisfactorily as sub-
grade or sub base material if properly
grade or sub base material if properly
drained or properly compacted.
drained or properly compacted.

The AASHTO
The AASHTO
2. Materials classified as A-4, A-5, A-6, A-
2. Materials classified as A-4, A-5, A-6, A-
7-5, A-7-6 will require a layer of sub base
7-5, A-7-6 will require a layer of sub base
material if used as sub-grade. If these
material if used as sub-grade. If these
are to be used as embankment materials,
are to be used as embankment materials,
special attention should be given to the
special attention should be given to the
design of the embankment.
design of the embankment.

Group Index
Group Index
GI=(F-35)[0.2+0.005(LL-40)+0.01(F-15)(PI-10)]
GI=(F-35)[0.2+0.005(LL-40)+0.01(F-15)(PI-10)]
Where:
Where:
GI = group index
GI = group index
F = percentage of the soil passing # 200 sieve
F = percentage of the soil passing # 200 sieve
LL= liquid limit of the soil
LL= liquid limit of the soil
PI = plasticity index
PI = plasticity index

Sample Problems
Sample Problems
6.
6. Classify the soil using AASHTO soil
Classify the soil using AASHTO soil
Passing (mm)
Passing (mm) %
%
38
38 100
100
20
20 65
65
0.425
0.42545
45
0.075
0.07530
30
w
w l
l 35
35
Ip
Ip 21
21

Sample Problems
Sample Problems
Sieve No.
Sieve No. % finer
% finer
4
4 97
97
10
10 93
93
40
40 88
88
100
100 78
78
200
200 70
70
w
w l
l 48
48
Ip
Ip 26
26

Classify using unified
Classify using unified
AASHTO
AASHTO
A
A B
B C
C D
D E
E F
F
1 1/2in
1 1/2in 100
100
3/4in
3/4in 100
100
3/8in
3/8in 95
95 80
80
4
4 86
86 51
51
10
10 71
71 100
100 100
100 40
40
20
20 57
57 91
91 100
100 100
100 29
29
40
40 46
46 70
70 73
73 22
22
100
100 33
33 20
20 82
82 13
13
200
200 26
26 8
8 56
56 70
70 89
89 9
9
wl
wl 30
30 48
48 41
41 39
39 13
13
Ip
Ip 18
18 NP
NP 8
8 8
8 22
22 3
3

Information Required in
Information Required in
Soil Investigation
Soil Investigation
1.
1. Selection of road alignment
Selection of road alignment
2.
2. Decision on the need to treat the soil especially
Decision on the need to treat the soil especially
embankment
embankment
3.
3. Investigation of slope stability in cuts and
Investigation of slope stability in cuts and
embankments
embankments
4.
4. Location and design of ditches and culverts
Location and design of ditches and culverts
5.
5. Selection and design of road pavement
Selection and design of road pavement
6.
6. Location and evaluation of suitable borrow and
Location and evaluation of suitable borrow and
construction material
construction material
7.
7. Design of foundation of bridges and other structure
Design of foundation of bridges and other structure

Method of Sub-surface
Method of Sub-surface
Investigation
Investigation
1.
1. Geophysical method
Geophysical method
2.
2. Probing or jetting with a stream of water
Probing or jetting with a stream of water
3.
3. Test pits or trenches
Test pits or trenches
4.
4. Hand augers
Hand augers
5.
5. Boring test holes and sampling with drill
Boring test holes and sampling with drill
rigs
rigs

Method Used in In-Place
Method Used in In-Place
Testing
Testing
1.
1. Standard penetration test
Standard penetration test
2.
2. Cone-depth of fill and depth of layer
Cone-depth of fill and depth of layer
changes
changes
3.
3. Vane-shear strength and cohesion
Vane-shear strength and cohesion

Depth of Investigation
The design depth is defined as the depth from
The design depth is defined as the depth from
the finished road level to the depth that the
the finished road level to the depth that the
load bearing strength of the soil no longer has
load bearing strength of the soil no longer has
an effect on the pavement’s performance in
an effect on the pavement’s performance in
relation to traffic loading. Properties of soil
relation to traffic loading. Properties of soil
below the design depth may indirectly affect
below the design depth may indirectly affect
pavement performance, but are generally
pavement performance, but are generally
unrelated to traffic loading. The depth of test
unrelated to traffic loading. The depth of test
pits and boring should in no case be less than
pits and boring should in no case be less than
1.5m below the proposed sub-grade level
1.5m below the proposed sub-grade level
unless rock material is encountered.
unless rock material is encountered.

For ordinary work, it is sufficient to go to a
For ordinary work, it is sufficient to go to a
depth of about 3m below the proposed
depth of about 3m below the proposed
foundation level in areas of cut and 3m
foundation level in areas of cut and 3m
below the existing ground in areas of fill.
below the existing ground in areas of fill.

Testing Frequency
Testing Frequency
Road type
Road type Indicator’s test
Indicator’s test Strength test
Strength test
Paved trunk
Paved trunk
road
road
Min.4/km
Min.4/km Min.2/km
Min.2/km
Other paved
Other paved
roads
roads
Min.2/km
Min.2/km Min.1/km
Min.1/km
Gravel road
Gravel road Min.2/km
Min.2/km Min.1/2km
Min.1/2km

Essential laboratory test
Essential laboratory test
 Particle size distribution test
Particle size distribution test
 Water content
Water content
 Atterberg limits
Atterberg limits
 Soil compaction
Soil compaction
 Laboratory compaction test
Laboratory compaction test
 Field density test
Field density test
 Nuclear method
Nuclear method
 California bearing ratio test
California bearing ratio test
 Resilient modulus test
Resilient modulus test

Soil Reports
Soil Reports
1.
1. Test hole location
Test hole location
2.
2. Field notes on test hole logs
Field notes on test hole logs
3.
3. Laboratory test
Laboratory test
4.
4. Soil profile
Soil profile

Soil Compaction
Soil Compaction
Proper compaction of the soil will
Proper compaction of the soil will
reduce to a subsequent settlement and
reduce to a subsequent settlement and
volume changes, thereby enhancing the
volume changes, thereby enhancing the
strength of the embankment or sub base.
strength of the embankment or sub base.

Compaction
Compaction
It is achieved in the field by using
It is achieved in the field by using
hand-operated tampers, sheepsfoot
hand-operated tampers, sheepsfoot
rollers, rubber-tired rollers and other
rollers, rubber-tired rollers and other
types of compacting equipment.
types of compacting equipment.
The density of the soil as
The density of the soil as
compacted is measured and compared to
compacted is measured and compared to
the density goal for the soil as previously
the density goal for the soil as previously
determined in the laboratory test using
determined in the laboratory test using
the standard proctor apparatus.
the standard proctor apparatus.

Field Density Tests
Field Density Tests
1.
1. Rubber balloon method
Rubber balloon method
2.
2. Sand cone apparatus
Sand cone apparatus
3.
3. Nuclear method
Nuclear method

Special Soil Test for
Special Soil Test for
Pavement
Pavement
1.
1. CBR
CBR
2.
2. Hveem Stabilometer Test
Hveem Stabilometer Test

Chapter III
Chapter III
Aggregates
Aggregates

Aggregates
Aggregates
It is a granular mineral particles
It is a granular mineral particles
used either in combination with various
used either in combination with various
types of cementing materials to form
types of cementing materials to form
concrete, backfill or road sub base.
concrete, backfill or road sub base.

Uses of Aggregates
Uses of Aggregates
 Portland cement concrete
Portland cement concrete
 Macadam or asphalt concrete
Macadam or asphalt concrete
 Asphalt surfaces
Asphalt surfaces
 Road base and sub base
Road base and sub base
 Railroad ballast
Railroad ballast
 Trench
Trench
 Backfill, fill under floor slab
Backfill, fill under floor slab
 Concrete blocks
Concrete blocks
 Water filtration bed, drainage structure
Water filtration bed, drainage structure
 Riprap, grouted riprap and gabion materials
Riprap, grouted riprap and gabion materials

Properties of Aggregates
Properties of Aggregates
1.
1. Gradation
Gradation
2.
2. Relative density and absorption
Relative density and absorption
3.
3. Hardness
Hardness
4.
4. Durability
Durability
5.
5. Particle shape and surface texture
Particle shape and surface texture
6.
6. Crushing strength
Crushing strength
7.
7. Chemical stability
Chemical stability
8.
8. Deleterious substance
Deleterious substance

Specifications of Highway
Specifications of Highway
Base Coarse
Base Coarse
Gradation Requirement
Gradation Requirement
Passing 25 mm (1in)
Passing 25 mm (1in) -100%
-100%
19 mm (3/4)
19 mm (3/4) -90-100%
-90-100%
9.5 mm (3/8)
9.5 mm (3/8) -50-75%
-50-75%
4.75 mm (#4)
4.75 mm (#4) -35-55%
-35-55%
1.18 mm (#16)
1.18 mm (#16) -15-40%
-15-40%
300microm (#50)
300microm (#50) -5-22%
-5-22%
75microm (#200)
75microm (#200) -2-8%
-2-8%
Physical Properties
Physical Properties
Abrasion Lost
Abrasion Lost Max. Allowable=40%
Max. Allowable=40%
Soundness Test
Soundness Test Max. Allowable=18%
Max. Allowable=18%

Blending of Aggregates
Blending of Aggregates
 Mixing of two aggregates of different
Mixing of two aggregates of different
gradation
gradation
 To satisfy the required gradation for the
To satisfy the required gradation for the
purpose
purpose
 To economically use the available
To economically use the available
aggregates
aggregates

Formulas to be used in
Formulas to be used in
trial and error method
trial and error method
aA+bB=T
aA+bB=T for two aggregates
for two aggregates
aA+bB+cC=T
aA+bB+cC=T for three aggregates
for three aggregates

Sub-base Coarse Material
Sub-base Coarse Material
 Platform for the construction separating the
Platform for the construction separating the
sub-grade and the base coarse
sub-grade and the base coarse
 Accepts the stresses applied to the pavement
Accepts the stresses applied to the pavement
 Requires a minimum CBR of 30
Requires a minimum CBR of 30
Minimum requirement for sub-bases
Minimum requirement for sub-bases
Plasticity Index (%)
Plasticity Index (%) <25
<25
Plasticity Modulus (PM)
Plasticity Modulus (PM) <500
<500
CBR
CBR >30
>30

Recommended Plasticity
Recommended Plasticity
Characteristics for Granular
Characteristics for Granular
Sub-base
Sub-base
Climate
Climate Typical
Typical
Annual
Annual
Rainfall
Rainfall
Liquid
Liquid
Limit
Limit
Plasticity
Plasticity
Index
Index
Linear
Linear
Shrinkage
Shrinkage
Moist
Moist
tropical and
tropical and
wet tropical
wet tropical
>500 mm
>500 mm <35
<35 <6
<6 <3
<3
Seasonally
Seasonally
wet tropical
wet tropical
>500 mm
>500 mm <45
<45 <12
<12 <6
<6
Arid and
Arid and
semi arid
semi arid
<500 mm
<500 mm <55
<55 <20
<20 <10
<10

Typical particle size
Typical particle size
distribution for sub-base
distribution for sub-base
Test Sieve (mm)
Test Sieve (mm) Percent Passing (%)
Percent Passing (%)
50
50 100
100
37.5
37.5 80-100
80-100
20
20 60-100
60-100
5
5 30-100
30-100
1.18
1.18 17-75
17-75
0.3
0.3 9-50
9-50
0.075
0.075 5-25
5-25

Gravel Surface Roads
Gravel Surface Roads
 A cheap weathered road
A cheap weathered road
 Constructed in a low minimum cost
Constructed in a low minimum cost
 Designed for an AADT of 350-400 with a
Designed for an AADT of 350-400 with a
minimum weight of 10 tons
minimum weight of 10 tons

Stabilized Pavement
Stabilized Pavement
Materials
Materials
 To increase the stability and strength of
To increase the stability and strength of
the materials especially soils by adding
the materials especially soils by adding
stabilizer
stabilizer
 Improve volume stability
Improve volume stability
 Lower the permeability of the soil
Lower the permeability of the soil

Four Techniques of
Four Techniques of
Stabilization
Stabilization
1.
1. Mechanical stabilization
Mechanical stabilization
2.
2. Cement stabilization
Cement stabilization
3.
3. Lime stabilization
Lime stabilization
4.
4. Bitumen stabilization
Bitumen stabilization

CHAPTER IV
CHAPTER IV
Bituminous Materials

Bitumens are hydrocarbon which are soluble in
Bitumens are hydrocarbon which are soluble in
carbon disulfate.
carbon disulfate.
They are usually fairly hard at normal
They are usually fairly hard at normal
temperature. When heated, they soften and
temperature. When heated, they soften and
flow.
flow.
When mixed with aggregate in their fluid state,
When mixed with aggregate in their fluid state,
and allowed to cool, they solidify and bind the
and allowed to cool, they solidify and bind the
aggregates together forming a pavement
aggregates together forming a pavement
surface.
surface.

Sources of Asphaltic
Sources of Asphaltic
Materials
Materials
 Natural deposits
Natural deposits
 Tars
Tars
 Petroleum asphalt
Petroleum asphalt
 Asphaltic cement
Asphaltic cement
 Liquid or cutback asphalt
Liquid or cutback asphalt
 Asphalt emulsion
Asphalt emulsion
 Cationic emulsion
Cationic emulsion
 Anionic emulsion
Anionic emulsion

3 Grades of emulsified
3 Grades of emulsified
asphalt
asphalt
1.
1. Rapid setting
Rapid setting
2.
2. Medium setting
Medium setting
3.
3. Slow setting
Slow setting

Quality control test of
Quality control test of
asphalt materials
asphalt materials
1.
1. Viscosity
Viscosity
1. Absolute viscosity
1. Absolute viscosity
2. Kinematic viscosity
2. Kinematic viscosity
3. Penetration
3. Penetration
2. Ductility
2. Ductility
3. Thin-film oven test
3. Thin-film oven test
4. Solubility
4. Solubility
5. Flashpoint
5. Flashpoint

Asphalt concrete
Asphalt concrete
It consists of asphalt cement, aggregates
It consists of asphalt cement, aggregates
and air.
and air.
It is normally known simply as asphalt, a
It is normally known simply as asphalt, a
composite material commonly used for
composite material commonly used for
construction of pavement, highways and
construction of pavement, highways and
parking lots.
parking lots.
It consists of asphalt binder and mineral
It consists of asphalt binder and mineral
aggregate mixed together then lay down in
aggregate mixed together then lay down in
layers and compacted.
layers and compacted.

Several methods of
Several methods of
preparation of asphalt
preparation of asphalt
concrete
concrete
 Hot mix asphalt concrete
Hot mix asphalt concrete
 Warm mix asphalt concrete
Warm mix asphalt concrete
 Cold mix asphalt concrete
Cold mix asphalt concrete
 Cut-back asphalt concrete
Cut-back asphalt concrete
 Mastic asphalt concrete
Mastic asphalt concrete

Specified requirements to
Specified requirements to
control the failure in
control the failure in
pavements
pavements
1.
1. Aggregates should be strong and durable
Aggregates should be strong and durable
2.
2. Asphalt should be well-tested
Asphalt should be well-tested
3.
3. Application of maximum temperature
Application of maximum temperature
4.
4. Maximum % of air voids in the mixture
Maximum % of air voids in the mixture
5.
5. Minimum % of air voids in the binder
Minimum % of air voids in the binder
6.
6. Minimum % of VMA
Minimum % of VMA
7.
7. Asphalt content must not be too high for
Asphalt content must not be too high for
stability
stability

Steps for the asphalt
Steps for the asphalt
concrete design mix
concrete design mix
1.
1. Selection of aggregate proportion to meet the
Selection of aggregate proportion to meet the
specification requirements
specification requirements
2.
2. Conducting trial mixes at a range of asphalt
Conducting trial mixes at a range of asphalt
content and measuring the resulting physical
content and measuring the resulting physical
properties of the sample
properties of the sample
3.
3. Analysing the result to obtain the optimum
Analysing the result to obtain the optimum
asphalt content to determine if the
asphalt content to determine if the
specification can be met
specification can be met
4.
4. Repeating with additional trial mixes using
Repeating with additional trial mixes using
different aggregate blends until suitable
different aggregate blends until suitable
design is found
design is found

The Marshall method
The Marshall method
1.
1. Aggregates are blended in proportion that meet the
Aggregates are blended in proportion that meet the
specification
specification
2.
2. The mixing and compacting temperature for the asphalt cement
The mixing and compacting temperature for the asphalt cement
being used are obtained from the temperature viscosity graph.
being used are obtained from the temperature viscosity graph.
These temperatures are those required to produce viscosities of
These temperatures are those required to produce viscosities of
1.7
1.7± 0.2cm
± 0.2cm2
2
/sec for mixing and 2.8 ± 0.3cm
/sec for mixing and 2.8 ± 0.3cm2
2
/sec for
/sec for
compacting.
compacting.
3.
3. The number of briquettes, 101.6mm in diameter and 60-65mm
The number of briquettes, 101.6mm in diameter and 60-65mm
high are mixed using 1200g of aggregates and asphalt cement
high are mixed using 1200g of aggregates and asphalt cement
of various percentages both above and below the expected
of various percentages both above and below the expected
optimum.
optimum.
4.
4. Briquettes are heated to 60
Briquettes are heated to 600
0
C. Stability and flow is measured in
C. Stability and flow is measured in
Marshall test apparatus to measure the strength and flexibility.
Marshall test apparatus to measure the strength and flexibility.

Inspection and quality
control
control
1.
1. Aggregate stock piles and cold fed controls
Aggregate stock piles and cold fed controls
2.
2. Gradation of materials in each hot bin and the
Gradation of materials in each hot bin and the
operation of the proportioning system
operation of the proportioning system
3.
3. Temperature of aggregate, asphalt and the
Temperature of aggregate, asphalt and the
mixture being produced
mixture being produced
4.
4. Operation of the dryer and the mixer
Operation of the dryer and the mixer
5.
5. Quality of the mix in the delivery truck
Quality of the mix in the delivery truck

control in the site
control in the site
1.
1. Suitability of the base coarse compaction
Suitability of the base coarse compaction
percentage based on CBR
percentage based on CBR
2.
2. Completed highway structures such as
Completed highway structures such as
bridge, cross drainage, and alignment
bridge, cross drainage, and alignment
drainage
drainage
3.
3. Temperature during the asphalt paving
Temperature during the asphalt paving
procedures
procedures
4.
4. Quality of the mix in the delivery truck
Quality of the mix in the delivery truck
5.
5. Proper method of asphalt concrete
Proper method of asphalt concrete
application
application
6.
6. Testing of the finished pavement
Testing of the finished pavement

Other asphalt application
Other asphalt application
1.
1. Surface treatment
Surface treatment
2.
2. Seal coats
Seal coats
3.
3. Prime coats
Prime coats

Sample Problems
Sample Problems
1.
1. Find the grain size distribution.
Find the grain size distribution.
Mass of sample
Mass of sample = 446.7g
= 446.7g
Mass after washing
Mass after washing = 414.1g
= 414.1g
Results after drying
Results after drying
Retained in 4.75mm
Retained in 4.75mm 0.0g
0.0g
1.18mm
1.18mm 205.3g
205.3g
0.3mm
0.3mm 127.9g
127.9g
0.075mm
0.075mm 76.4g
76.4g
pan
pan 3.8g
3.8g

Sample Problems
Sample Problems
2. Determine the maximum dry density and
2. Determine the maximum dry density and
optimum moisture content of the given data.
optimum moisture content of the given data.
Trial No.
Trial No. Dry density (kg/m
Dry density (kg/m3
3
)
) w(%)
w(%)
1
1 1862
1862 6.8
6.8
2
2 1894
1894 9.1
9.1
3
3 1927
1927 11.0
11.0
4
4 1929
1929 12.8
12.8
5
5 1883
1883 15.0
15.0
6
6 1836
1836 16.6
16.6

Sample Problems
Sample Problems
3. Find the water content and the dry density of the
3. Find the water content and the dry density of the
given sample for the standard compaction test.
given sample for the standard compaction test.
V
Vmold
mold = 943.9cm
= 943.9cm3
3
Density Sample
Density Sample
Mass of soil + mold = 5321g
Mass of mold
Mass of mold = 3449g
= 3449g
Water Content Sample
Water Content Sample
Mass of Sample + container = 252.6g
Mass of Sample + container = 252.6g
Mass of dry sample + container = 238.04g
Mass of container = 104.73g

Sample Problems
Sample Problems
4. Find the density and optimum water content.
4. Find the density and optimum water content.
Results of the standard compaction test
Results of the standard compaction test
Trial 1
Trial 1 Mass of soil + mold = 5619g
Water content test
Water content test
Mass of sample + container = 288.26g
Mass of sample + container = 288.26g
Trial 2
Trial 2 Dry density = 1795kg/m
Dry density = 1795kg/m3
3
;w=14.9%
;w=14.9%
Trial 3
3
;w=15.6%
;w=15.6%
Trial 4
3
;w=16.5%
;w=16.5%
Trial 5
3
;w=17.6%
;w=17.6%

Sample Problems
Sample Problems
5. An unconfined compression test is
5. An unconfined compression test is
conducted on a soft clay sample with a
conducted on a soft clay sample with a
diameter of 1.40 in and a length of 2.9 in.
diameter of 1.40 in and a length of 2.9 in.
The sample bulged during the test
The sample bulged during the test
without reaching a maximum value. At a
without reaching a maximum value. At a
strained of 20% (0.58in), the load was
strained of 20% (0.58in), the load was
17.05lb. Find the shear strength.
17.05lb. Find the shear strength.

Sample Problems
Sample Problems
6. In a direct shear test, the total normal
6. In a direct shear test, the total normal
force on the sample is 165N. The shear
force on the sample is 165N. The shear
force required for failure is 104N. The
force required for failure is 104N. The
sample is 10cm in diameter. Find the
sample is 10cm in diameter. Find the
normal and shear stress in kPa.
normal and shear stress in kPa.

Sample Problems
Sample Problems
7. A cohesionless sand is tested in a direct
7. A cohesionless sand is tested in a direct
shear apparatus with a square box
shear apparatus with a square box
6.00cm in size. Normal load at failure is
6.00cm in size. Normal load at failure is
93.8N with a maximum shear load of
93.8N with a maximum shear load of
38.7N. Find the stresses in failure plane
38.7N. Find the stresses in failure plane
and the angle of friction. Identify the
and the angle of friction. Identify the
equation for shear strength.
equation for shear strength.

Sample Problems
Sample Problems
8. Three direct shear tests are conducted on a
8. Three direct shear tests are conducted on a
silty clay with the following results.
silty clay with the following results.
Test
Test σ
σ τ
τ
1
1 28
28 32.4
32.4
2
2 56
56 36.9
36.9
3
3 84
84 41.6
41.6
Plot the test result. Obtain the values of c and
Plot the test result. Obtain the values of c and φ
φ
for the soil and determine the shear strength
for the soil and determine the shear strength
equation.
equation.

Sample Problems
Sample Problems
9. Soil in a highway is compacted in a unit
9. Soil in a highway is compacted in a unit
weight of 133pcf. A sample of it is tested
weight of 133pcf. A sample of it is tested
for water content. The original mass was
for water content. The original mass was
163.5g and the dry mass was 140.4g.
163.5g and the dry mass was 140.4g.
Find the dry density of the highway soil.
Find the dry density of the highway soil.

Sample Problems
Sample Problems
10. Laboratory maximum density of the soil
10. Laboratory maximum density of the soil
is 1900kg/m
is 1900kg/m3
3
. Specification requires 95%
. Specification requires 95%
compaction. In the field, dry condition of
compaction. In the field, dry condition of
the soil is found to be 1810kg/m
the soil is found to be 1810kg/m3
3
. A
. A
visual check of the soil in the field
visual check of the soil in the field
indicates that it contains about 20%
indicates that it contains about 20%
gravel size. Check for compaction.
gravel size. Check for compaction.

Sample Problems
Sample Problems
11. Given:
11. Given: Original mass=608.5g
Original mass=608.5g
Dry mass after washing=578.2g
Dry mass after washing=578.2g
Sieve No.
Sieve No. Mass Retained (g)
Mass Retained (g)
3/8
3/8 0.00
0.00
4
4 96.2
96.2
8
8 117.8
117.8
16
16 128.8
128.8
30
30 105.3
105.3
50
50 82.7
82.7
100
100 29.3
29.3
200
200 14.7
14.7
pan
pan 2.7
2.7
Employ complete calculation.
Employ complete calculation.

Sample Problems
Sample Problems
12. In a relative density test of an
12. In a relative density test of an
aggregate sample, the following are
aggregate sample, the following are
recorded.
recorded.
Dry mass
Dry mass 2117.1g
2117.1g
SSD mass
SSD mass 2144.3g
2144.3g
Net volume
Net volume 786.8cm
786.8cm3
3
Find the bulk relative density values.
Find the bulk relative density values.

Sample Problems
Sample Problems
13.
13. SSD mass
SSD mass 2034.2g
2034.2g
Submerged mass
Submerged mass 1276.1g
1276.1g
Dry mass
Dry mass 2017.1g
2017.1g
Find the relative density values.
Find the relative density values.

Sample Problems
Sample Problems
14. React on the result of the laboratory
14. React on the result of the laboratory
test on aggregate.
test on aggregate.
From Abrasion test
From Abrasion test
M
Mo
o = 5008.7g
= 5008.7g
M
Mf
f = 2764.9g
= 2764.9g

Sample Problems
Sample Problems
15. A soundness test is conducted on
15. A soundness test is conducted on
coarse aggregate. The original mass of
coarse aggregate. The original mass of
the sample was 2125g. After completion
the sample was 2125g. After completion
of the test, the dry mass of the particles
of the test, the dry mass of the particles
that have not broken down is found to be
that have not broken down is found to be
1849g. Find the percent loss. React on
1849g. Find the percent loss. React on
the answer.
the answer.

Sample Problems
Sample Problems
16. A highway department includes the following requirements in its specification for 19-4.75mm
16. A highway department includes the following requirements in its specification for 19-4.75mm
coarse aggregate to be used in asphalt pavement.
coarse aggregate to be used in asphalt pavement.
a. Gradation pass
a. Gradation pass
25mm
25mm 100%
100%
19mm
19mm 90-100%
90-100%
9.5mm
9.5mm 25-60%
25-60%
4.75mm
4.75mm 0-10%
0-10%
b. Materials finer than 0.075mm, 1.5% max.as measured in washing test.
b. Materials finer than 0.075mm, 1.5% max.as measured in washing test.
c. Amount of crushed particle, 60% max.
c. Amount of crushed particle, 60% max.
d. Amount of flat and elongated particles, 20% max.
d. Amount of flat and elongated particles, 20% max.
Results of laboratory test
Results of laboratory test
Washing test
Washing test
Total mass = 1981.3g
Total mass = 1981.3g
Crushed particle test
Crushed particle test
Total mass = 1262g
Total mass = 1262g
Amount crushed = 677g
Amount crushed = 677g
Flat and elongated particles
Flat and elongated particles
Total mass = 1719g
Total mass = 1719g
Amount of F and E P = 215g
Amount of F and E P = 215g
Check the aggregate according to specification
Check the aggregate according to specification

Sample Problems, Cont…
Sieve analysis
Sieve analysis
Total sample
Total sample = 8419g
= 8419g
Sieve (mm)
Sieve (mm) Mass retained (g)
Mass retained (g)
25
25 0
0
19
19 622
622
12.5
12.5 2955
2955
9.5
9.5 2619
2619
4.75
4.75 1844
1844
pan
pan 378
378
Check the aggregate for acceptance according to
Check the aggregate for acceptance according to
specification.
specification.

Sample Problems
Sample Problems
a.
a. Specification for a highway project requires compaction equal to 98%
Specification for a highway project requires compaction equal to 98%
laboratory maximum density.
laboratory maximum density.
b.
b. Proctor compaction test on the soil being used results in maximum dry
Proctor compaction test on the soil being used results in maximum dry
density of 2106kg/m
density of 2106kg/m3
3
and an OWC of 8.2%.
and an OWC of 8.2%.
c.
c. The sand cone test apparatus is calibrated in the laboratory as follows:
The sand cone test apparatus is calibrated in the laboratory as follows:
Mass required to fill the cone = 773g
Mass required to fill the cone = 773g
Mass required to fill the proctor mold = 1421g
Mass required to fill the proctor mold = 1421g
d. The field density test is conducted with the following results:
d. The field density test is conducted with the following results:
Mass of sand, bottle and cone before test = 6491g
Mass of sand, bottle and cone before test = 6491g
Mass of sand, bottle and cone after test = 3217g
Mass of sand, bottle and cone after test = 3217g
Mass of sample from test hole + container = 3820.5g
Mass of sample from test hole + container = 3820.5g
Water content test of the sample
Water content test of the sample
Total mass + container = 283.12g
Total mass + container = 283.12g
Dry mass + container = 263.82g
Dry mass + container = 263.82g
What result would you report?
What result would you report?

Sample Problems
Sample Problems
Specification requires 96% compaction on
Specification requires 96% compaction on
a project. Maximum dry unit weight was
a project. Maximum dry unit weight was
found to be 114lb/ft3 at a water content
found to be 114lb/ft3 at a water content
of 13.5 % in lab test. Results in the field
of 13.5 % in lab test. Results in the field
density test were: dry unit weight =
density test were: dry unit weight =
111pcf and water content = 11%. A
111pcf and water content = 11%. A
sample in the field contain at about 15%
sample in the field contain at about 15%
gravel. Is the compaction satisfactory?
gravel. Is the compaction satisfactory?

Sample Problems
Sample Problems
Specifications for highway require that the soil be compacted to 95% of standard
Specifications for highway require that the soil be compacted to 95% of standard
laboratory dry density. Test on soil in one section of the road indicates that it has
laboratory dry density. Test on soil in one section of the road indicates that it has
a maximum dry density of 121.7pcf at an optimum water content of 11.8%. Field
a maximum dry density of 121.7pcf at an optimum water content of 11.8%. Field
density test are conducted as 5 locations. Reports on the result are detailed
density test are conducted as 5 locations. Reports on the result are detailed
below. Is the compaction satisfactory? Should water be added? Why?
below. Is the compaction satisfactory? Should water be added? Why?
a.
a. Nuclear densometer
Nuclear densometer
Total density = 130.4pcf
w = 11.0%
w = 11.0%
b. Test hole
b. Test hole d. Test hole
d. Test hole
V = 0.03241ft
V = 0.03241ft3
3
V = 0.02896ft
V = 0.02896ft3
3
Mt = 4.511lb
Mt = 4.511lb Mt = 3.677lb
Mt = 3.677lb
Md = 4.018lb
Md = 4.018lb w = 14.5%
w = 14.5%
c. Test hole
c. Test hole
V = 0.03542ft
V = 0.03542ft3
3
e. Nuclear densometer
e. Nuclear densometer
Mt = 4.379lb
Mt = 4.379lb Total density = 123.9pcf
For moisture content
For moisture content Moisture density = 10.7pcf
Moisture density = 10.7pcf
Mo = 199.5g
Mo = 199.5g
Md = 183.7g
Md = 183.7g

Sample Problems
Sample Problems
A combined aggregate sample is split on a no.4 sieve, sieved through the
A combined aggregate sample is split on a no.4 sieve, sieved through the
coarse sieve, split down to an acceptable size, washed and sieved
coarse sieve, split down to an acceptable size, washed and sieved
through the fine sieve. Calculate the grain size distribution and check for
through the fine sieve. Calculate the grain size distribution and check for
acceptance as a base coarse material according to gradation
acceptance as a base coarse material according to gradation
requirement.
requirement.
Original sample = 12387g
Original sample = 12387g
Mass of coarse fraction = 7524g
Mass of coarse fraction = 7524g
Mass of fine fraction = 4860g
Mass of fine fraction = 4860g
Coarse sieving
Coarse sieving
Retained on
Retained on 25mm
25mm 0g
0g
19mm
19mm 377g
377g
12.5mm
12.5mm 1399g
1399g
9.5mm
9.5mm 2643g
2643g
4.75mm
4.75mm 2956g
2956g
pan
pan 144g
144g

Fine fraction split down
Fine fraction split down
Original sample
Original sample = 533.7g
= 533.7g
Washed sample
Washed sample= 512.7g
= 512.7g
Fine sieving
Fine sieving
Retained on
Retained on 4.75mm
4.75mm 0.0g
0.0g
2.36mm
2.36mm 105.9g
105.9g
1.18mm
1.18mm 126.6g
126.6g
0.6mm
0.6mm 77.4g
77.4g
0.3mm
0.3mm 105.1g
105.1g
0.15mm
0.15mm 56.8g
56.8g
0.075mm
0.075mm 32.5g
32.5g
pan
pan 7.2g
7.2g

Combine the 3 aggregates to give a
Combine the 3 aggregates to give a
gradation falling approximately in the
gradation falling approximately in the
center of the gradation specs
center of the gradation specs
Passing
Passing
(mm)
(mm)
A
A B
B C
C Specs
Specs
25
25 100
100 100
100
19
19 92
92 90-100
90-100
9.5
9.5 41
41 100
100 100
100 72-88
72-88
4.75
4.75 19
19 77
77 96
96 45-65
45-65
2.36
2.36 7
7 60
60 79
79 30-60
30-60
0.6
0.6 4
4 42
42 40
40 16-40
16-40
0.3
0.3 2
2 36
36 16
16 8-25
8-25
0.075
0.075 1
1 28
28 3
3 3-8
3-8

These aggregates are to be combined in a 50-50
These aggregates are to be combined in a 50-50
mixture for asphalt mix. Find the resulting
mixture for asphalt mix. Find the resulting
gradation. Check for acceptance.
gradation. Check for acceptance.
Passing
Passing
(mm)
(mm)
A
A B
B Specs
Specs
25
25 100
100 100
100
19
19 96.4
96.4 90-100
90-100
12.5
12.5 48.5
48.5 100
100 60-80
60-80
9.5
9.5 12.7
12.7 91.7
91.7 25-60
25-60
4.75
4.75 2.9
2.9 13.0
13.0 0-10
0-10
2.36
2.36 4.2
4.2 0-6
0-6

Sample Problems
Sample Problems
An asphalt mix contains 2250kg of
An asphalt mix contains 2250kg of
aggregates and 150kg of asphalt binder
aggregates and 150kg of asphalt binder
per cubic meter. Asphalt absorption of
per cubic meter. Asphalt absorption of
the aggregates is 1.2%. The bulk relative
the aggregates is 1.2%. The bulk relative
density of the aggregate is 2.67 and the
density of the aggregate is 2.67 and the
relative density of the asphalt is 1.05.
relative density of the asphalt is 1.05.
Find the density, asphalt content and the
Find the density, asphalt content and the
air voids, VMA and VFA.
air voids, VMA and VFA.

Sample Problems
Sample Problems
Given:
Given:
ρ
ρ = 2240kg/m
= 2240kg/m3
3
Pb
Pb = 5.8%
= 5.8%
Pba
Pba = 0.8%
= 0.8%
RDb
RDb = 2.67
= 2.67
RD asphalt = 1.03
RD asphalt = 1.03
Find: AV, VMA, VFA
Find: AV, VMA, VFA

Sample Problems
Sample Problems
An asphalt concrete mixture has a density
An asphalt concrete mixture has a density
of 2385kg/m
of 2385kg/m3
3
. The asphalt content is
. The asphalt content is
6.8% and asphalt absorption of 0.9%.
6.8% and asphalt absorption of 0.9%.
The relative density of aggregate is 2.67,
The relative density of aggregate is 2.67,
of the asphalt 1.05. Find the percentages
of the asphalt 1.05. Find the percentages
of air void, VMA and VFA.
of air void, VMA and VFA.

Marshall stability
Marshall stability
correction factor
correction factor
Volume (cm3)
Volume (cm3) Factor
Factor
457-470
457-470 1.19
1.19
471-482
471-482 1.14
1.14
483-495
483-495 1.09
1.09
496-508
496-508 1.04
1.04
509-522
509-522 1.00
1.00
523-535
523-535 0.96
0.96
536-546
536-546 0.93
0.93
547-559
547-559 0.89
0.89
560-573
560-573 0.86
0.86

Sample Problems
Sample Problems
Test on Marshall briquette yielded the result shown. The aggregate was
Test on Marshall briquette yielded the result shown. The aggregate was
made up of 45% A, 35% B and 20% C with relative density values of 2.72,
made up of 45% A, 35% B and 20% C with relative density values of 2.72,
2.67, and 2.64 respectively. Calculate the density, stability, flow,
2.67, and 2.64 respectively. Calculate the density, stability, flow,
percentage of air voids and VMA. The relative density of the asphalt
percentage of air voids and VMA. The relative density of the asphalt
cement is 1.01 and the asphalt absorption is 1.0%.
cement is 1.01 and the asphalt absorption is 1.0%.
Mixing data
Mixing data
Mass of aggregate = 1200g
Mass of aggregate = 1200g
Mass of asphalt = 58g
Mass of asphalt = 58g
Briquette data
Briquette data
Mass in air = 1241.3g
Mass submerged = 712.7g
Stability test
Stability test
Maximum load = 5610N (1260lb)
Maximum load = 5610N (1260lb)
At a strain of = 2.4mm (0.094in)
At a strain of = 2.4mm (0.094in)

Sample Problems
Sample Problems
A 45:50:5 combination of aggregate is achieved in blending of aggregate. To
A 45:50:5 combination of aggregate is achieved in blending of aggregate. To
insure that no segregation will occur in sampling of briquette, aggregate A
insure that no segregation will occur in sampling of briquette, aggregate A
and B are divided into 2 sizes. Of aggregate A, 58% passes 3/8in; of
and B are divided into 2 sizes. Of aggregate A, 58% passes 3/8in; of
aggregate B, 38% passing no.16. The total weight of aggregate for
aggregate B, 38% passing no.16. The total weight of aggregate for
briquette is 1200g. Find the corresponding weight of each aggregate size.
briquette is 1200g. Find the corresponding weight of each aggregate size.
The asphalt content is 6.4%
The asphalt content is 6.4%
The density determination
The density determination
Relative densities: A = 2.68, B = 2.71, C = 2.64
Relative densities: A = 2.68, B = 2.71, C = 2.64
Asphalt absorption = 0.9%
Asphalt absorption = 0.9%
Relative density of asphalt = 1.06%
Relative density of asphalt = 1.06%
Stability, N = 5780N
Stability, N = 5780N
Fi = 29
Fi = 29
Ff = 40
Ff = 40
Check for Marshall criteria.
Check for Marshall criteria.

Sample Problems
Sample Problems
The asphalt is producing 1360kg per batch. Materials stored in three
The asphalt is producing 1360kg per batch. Materials stored in three
hot bins before mixing. Test were made on samples from the three
hot bins before mixing. Test were made on samples from the three
bins, with results as follows: Pb=6.2%.
bins, with results as follows: Pb=6.2%.
Required grain size distribution of the mix
Required grain size distribution of the mix
Passing 25mm
Passing 25mm 100%
100%
9.5mm
9.5mm 63%
63%
2.36mm
2.36mm 41%
41%
Coarse bin
Coarse bin Medium bin
Medium bin Fine bin
Fine bin
25mm - 100%
25mm - 100% 9.5mm – 100%
9.5mm – 100% 2.36mm – 100%
2.36mm – 100%
12.5mm – 73%
12.5mm – 73% 4.75mm – 75%
4.75mm – 75% 1.18mm – 73%
1.18mm – 73%
9.5mm – 18%
9.5mm – 18% 2.36mm – 33%
2.36mm – 33% 0.6mm – 52%
0.6mm – 52%
2.36mm – 1%
2.36mm – 1% 1.18mm – 11%
1.18mm – 11% 0.3mm – 33%
0.3mm – 33%

Sample problems
Sample problems
In designing an asphalt concrete mixture for a highway pavement to support
In designing an asphalt concrete mixture for a highway pavement to support
a very heavy traffic, data below are provided for aggregates and the
a very heavy traffic, data below are provided for aggregates and the
results of the Marshall test. Check the adequacy of the data. Determine
results of the Marshall test. Check the adequacy of the data. Determine
the optimum asphalt content
the optimum asphalt content.
.
Aggregate type
Aggregate type % by weight of
% by weight of
the total paving
the total paving
mixture
mixture
Bulk Specific
Bulk Specific
gravity
gravity
Coarse
Coarse 52.3
52.3 2.65
2.65
Fine
Fine 39.6
39.6 2.75
2.75
Filler
Filler 8.1
8.1 2.70
2.70

Sample problems cont..
Sample problems cont..
Pb
Pb Weight of the specimen(g)
Weight of the specimen(g)
Stability
Stability Flow
Flow
Bk
Bk
SG
SG
In air
In air In water
In water
1
1 2
2 3
3 1
1 2
2 3
3 1
1 2
2 3
3 1
1 2
2 3
3
5.0
5.0 1325.6
1325.6 1325.4
1325.4 1325.0
1325.0 780.1
780.1 780.3
780.3 779.8
779.8 1460
1460 1450
1450 1465
1465 7
7 7.5
7.5 7
7 2.54
2.54
5.5
5.5 1331.3
1331.3 1330.9
1330.9 1331.8
1331.8 789.6
789.6 789.3
789.3 790.0
790.0 1600
1600 1610
1610 1595
1595 10
10 9
9 9.5
9.5 2.56
2.56
6.0
6.0 1338.2
1338.2 1338.5
1338.5 1338.1
1338.1 798.6
798.6 798.3
798.3 797.3
797.3 1560
1560 1540
1540 1550
1550 11
11 11.5
11.5 11
11 2.58
2.58
6.5
6.5 1343.8
1343.8 1344.0
1344.0 1343.9
1343.9 799.8
799.8 797.3
797.3 799.9
799.9 1400
1400 1420
1420 1415
1415 13
13 13
13 13.5
13.5 2.56
2.56
7.0
7.0 1349.0
1349.0 1349.3
1349.3 1349.8
1349.8 798.4
798.4 799.0
799.0 800.1
800.1 1200
1200 1190
1190 1210
1210 16
16 15
15 16
16 2.54
2.54

Example for homogenous
soil
soil
A uniformly distributed load of intensity q is
A uniformly distributed load of intensity q is
applied to a circular area of radius a on the
applied to a circular area of radius a on the
surface of an incompressible v=0.5;
surface of an incompressible v=0.5;
homogeneous half space with an elastic
homogeneous half space with an elastic
modulus E. In terms of q, a and E, determine
modulus E. In terms of q, a and E, determine
the vertical displacement, the three principal
the vertical displacement, the three principal
stresses and the three principal strain at a
stresses and the three principal strain at a
point 2a below the surface under the edge of
point 2a below the surface under the edge of
the loaded area.
the loaded area.

soil
soil
A homogenous half space is subjected to
A homogenous half space is subjected to
circular loads each 254mm circular
circular loads each 254mm circular
diameter and space 508mm on centers.
diameter and space 508mm on centers.
The pressure on the circular area is
The pressure on the circular area is
345kPa. The half space has an elastic
345kPa. The half space has an elastic
modulus of 69MPa and a Poisson’s ratio of
modulus of 69MPa and a Poisson’s ratio of
0.5. Determine the vertical stress, strain
0.5. Determine the vertical stress, strain
and deflection at point a, which is located
and deflection at point a, which is located
254mm below the center of one circle.
254mm below the center of one circle.

soil
soil
From the previous example, use flexible
From the previous example, use flexible
plate using the first pressure only.
plate using the first pressure only.
Determine the stress, strain and
Determine the stress, strain and
deflection at point a.
deflection at point a.

soil
soil
A plate loading test using a plate 12in diameter
A plate loading test using a plate 12in diameter
was performed on the surface of the subgrade
was performed on the surface of the subgrade
shown below. A total load of 8000lb was
shown below. A total load of 8000lb was
applied to the plate and a deflection of 0.1in
applied to the plate and a deflection of 0.1in
was measured. Assuming v=0.4, determine the
was measured. Assuming v=0.4, determine the
elastic modulus of the subgrade.
elastic modulus of the subgrade.
8000lb Wo = 0.1in
V=0.4; E =?
6 in

Example for non-linear
Example for non-linear
A circular load with a radius of 6 in and a contact
A circular load with a radius of 6 in and a contact
pressure of 80psi is applied on the surface of
pressure of 80psi is applied on the surface of
the sub grade. The sub grade soil is a sand
the sub grade. The sub grade soil is a sand
with an elastic modulus of
with an elastic modulus of
E=18,800(1+0.0104
E=18,800(1+0.0104θ
θ). The soil has a
). The soil has a
Poisson’s ratio of 0.30, a mass unit weight of
Poisson’s ratio of 0.30, a mass unit weight of
110pcf and Ko= 0.5. Determine the vertical
110pcf and Ko= 0.5. Determine the vertical
surface displacement at the axis of symmetry.
surface displacement at the axis of symmetry.
Determine also the strain at z=12in. Use
Determine also the strain at z=12in. Use
Boussinesq’s stress distribution.
Boussinesq’s stress distribution.

Method of Flexible Pavement
Method of Flexible Pavement
Design
Design
4. Determine the cumulative number of
4. Determine the cumulative number of
ESA.
ESA.
Cumulative No. of ESA = Cumulative No.
Cumulative No. of ESA = Cumulative No.
of vehicle x Equivalency factor
of vehicle x Equivalency factor

Sample Problem for Layered
Sample Problem for Layered
System
System
A circular load with a radius of 6in and a uniform pressure of 80psi is
A circular load with a radius of 6in and a uniform pressure of 80psi is
applied on a 2 layer system as shown below. The sub-grade has
applied on a 2 layer system as shown below. The sub-grade has
an elastic modulus of 5000psi and can support a maximum
an elastic modulus of 5000psi and can support a maximum
vertical stress of 8psi. If the HMA has an elastic modulus of
vertical stress of 8psi. If the HMA has an elastic modulus of
500,000psi, what is the required thickness of a full depth
500,000psi, what is the required thickness of a full depth
pavement? If a thin surface treatment is applied on a granular
pavement? If a thin surface treatment is applied on a granular
base with E=25000psi, what is the thickness of the base coarse
base with E=25000psi, what is the thickness of the base coarse
required?
required?
80 psi
E1 = 500,000psi
E2 = 5000psi
σz= 8psi
h1
6inR

Sample Problem for Vertical
Surface Reflection
Surface Reflection
A total load of 20000lb was applied on a surface of a 2-layer system
A total load of 20000lb was applied on a surface of a 2-layer system
through a rigid plate 12in in diameter. Layer 1 has a thickness of
through a rigid plate 12in in diameter. Layer 1 has a thickness of
8in and layer 2 has an elastic modulus of 6400psi. Both layers are
8in and layer 2 has an elastic modulus of 6400psi. Both layers are
incompressible with a Poisson’s ratio of 0.5. If the deflection of
incompressible with a Poisson’s ratio of 0.5. If the deflection of
the plate is 0.1in, determine the elastic modulus of layer 1.
the plate is 0.1in, determine the elastic modulus of layer 1.
E1 = ?
E2 = 6400psi
8 in
V= 0.5
20000lb
6inR

Interface Deflection
Interface Deflection
The figure below shows a set of dual tires, each having a contact radius
The figure below shows a set of dual tires, each having a contact radius
of 115mm and a contact pressure of 483kPa. The center to center
of 115mm and a contact pressure of 483kPa. The center to center
spacing of the dual tires is 343mm. Layer 1 has a thickness of
spacing of the dual tires is 343mm. Layer 1 has a thickness of
152mm and an elastic modulus of 690MPa. Layer 2 has an elastic
152mm and an elastic modulus of 690MPa. Layer 2 has an elastic
modulus of 69MPa. Determine the vertical deflection at point A.
modulus of 69MPa. Determine the vertical deflection at point A.
h1=152mm
E1=690MPa
E2= 69MPa
343mm 155mmR

Sample Problem for Tensile
Sample Problem for Tensile
Strain
Strain
The figure below shows a full depth asphalt pavement of 8in thick
The figure below shows a full depth asphalt pavement of 8in thick
subjected to a single wheel load of 9000lbs having a contact
subjected to a single wheel load of 9000lbs having a contact
pressure of 67.7psi. If the elastic modulus of the asphalt layer is
pressure of 67.7psi. If the elastic modulus of the asphalt layer is
150000psi and that of the sub-grade is 15000psi, determine the
150000psi and that of the sub-grade is 15000psi, determine the
critical tensile strain in the asphalt layer.
critical tensile strain in the asphalt layer.
E1 = 150000psi
E2 = 15000psi
8 in
9000lb
6inR 67.7psi
e

Sample Problem for Dual-
Wheel Load
Wheel Load
From the figure below, determine the critical
From the figure below, determine the critical
tensile strain in the asphalt layer.
tensile strain in the asphalt layer.
E1 = 1.04GPa
E2 = 104MPa
203mm
e
20KN 20KN 467kPa
292mm

Tandem Load
Tandem Load
Determine the critical tensile strain.
Determine the critical tensile strain.
4500lb each
8in
E1= 150000psi
E2 = 15000psi
11.5in
49in

Sample Problem
Sample Problem
A circular load with a radius of 6in and a contact pressure of 80psi is
A circular load with a radius of 6in and a contact pressure of 80psi is
applied on the surface of the sub-grade. The sub-grade soil is
applied on the surface of the sub-grade. The sub-grade soil is
sand with a variation of elastic modulus of E=18,000(1+0.0104
sand with a variation of elastic modulus of E=18,000(1+0.0104θ
θ).
).
The soil has a Poisson ratio of 0.3, a mass unit weight of 110pcf,
The soil has a Poisson ratio of 0.3, a mass unit weight of 110pcf,
and a coefficient of earth pressure at rest of 0.5. The soil is
and a coefficient of earth pressure at rest of 0.5. The soil is
divided into 6 layers. Determine the vertical surface displacement
divided into 6 layers. Determine the vertical surface displacement
at the axis of symmetry.
at the axis of symmetry.
600in
5@12in
=
60in
6inR 80psi

Sample Problem for 3-Layer
Sample Problem for 3-Layer
System
System
From the 3-layer system below, with a=4.8in, q=120psi, h
From the 3-layer system below, with a=4.8in, q=120psi, h1
1=6in,
=6in,
h
h2
2=6in, E
=6in, E1
1=400000psi, E
=400000psi, E2
2=20000psi, E
=20000psi, E3
3=10000psi, determine the
=10000psi, determine the
stresses and strains at the 2 interfaces on the axis of symmetry.
stresses and strains at the 2 interfaces on the axis of symmetry.

Sample Problem for Corner
Sample Problem for Corner
Loading
Loading
Figure below shows a concrete slab subjected to a corner loading.
Figure below shows a concrete slab subjected to a corner loading.
Given k=100pci, h=10in, a=6in and P=10000lbs, determine the
Given k=100pci, h=10in, a=6in and P=10000lbs, determine the
maximum stress and deflection due to corner loading.
maximum stress and deflection due to corner loading.

Sample Problem for Interior
Sample Problem for Interior
Loading
Loading
Determine the stress and deflection due to
interior loading.
interior loading.

Sample Problem for Edge
Sample Problem for Edge
Loading
Loading
edge loading.
edge loading.

Sample Problem for Dual
Sample Problem for Dual
Tires
Tires
Apply for all cases.
Apply for all cases.

Sample Problem
Sample Problem
A set of dual tire is spaced at 34in center to
A set of dual tire is spaced at 34in center to
center and carries a total load of
center and carries a total load of
45000lbs with a tire pressure of 100psi.
45000lbs with a tire pressure of 100psi.
Assuming the pavement to be
Assuming the pavement to be
homogenous half-spaced, determine the
homogenous half-spaced, determine the
ESWL for the pavement of 25in using (a)
ESWL for the pavement of 25in using (a)
Boyd and Foster Method, (b) Foster and
Boyd and Foster Method, (b) Foster and
Alvin Method and (c) Huang’s Chart
Alvin Method and (c) Huang’s Chart
based on equal contact radius.
based on equal contact radius.

Sample Problem
Sample Problem
A full depth asphalt pavement is loaded by set of
A full depth asphalt pavement is loaded by set of
dual wheels, each weighing 8000lbs and
dual wheels, each weighing 8000lbs and
spaced 20in on centers. The hot mix asphalt
spaced 20in on centers. The hot mix asphalt
has a thickness of 10in and an elastic modulus
has a thickness of 10in and an elastic modulus
of 250000psi; the sub-grade has an elastic
of 250000psi; the sub-grade has an elastic
modulus of 10000psi. Both layers are
modulus of 10000psi. Both layers are
incompressible with a Poisson ratio of 0.5. If
incompressible with a Poisson ratio of 0.5. If
the dual wheels and the equivalent single
the dual wheels and the equivalent single
wheel have the same contact radius of 6in,
wheel have the same contact radius of 6in,
determine the ESWL on a. equal interface
determine the ESWL on a. equal interface
deflection, b. equal tensile strain.
deflection, b. equal tensile strain.

Sample Problem
Sample Problem
Determine the EALF for a 32kip tandem
Determine the EALF for a 32kip tandem
axle load and a 48kip tridem axle load.
axle load and a 48kip tridem axle load.
Use pt=2.5 and SN=5.
Use pt=2.5 and SN=5.

Sample Problem
Sample Problem
A 9in rigid pavement is subjected to a
A 9in rigid pavement is subjected to a
tandem axle load of 40000lbs. What is
tandem axle load of 40000lbs. What is
the EALF based on a pt=2.5?
the EALF based on a pt=2.5?

Sample Problem
Sample Problem
A flexible pavement with SN=5 is subjected
A flexible pavement with SN=5 is subjected
to a single axle load of 15000lbs. Based
to a single axle load of 15000lbs. Based
on a pt=2.5, what is the single axle load
on a pt=2.5, what is the single axle load
on a 9in rigid pavement that are
on a 9in rigid pavement that are
equivalent to the flexible pavement?
equivalent to the flexible pavement?

Design Example of Flexible
Pavement
Pavement
Traffic volume has been established for a link road in terms of AADT
Traffic volume has been established for a link road in terms of AADT
and as follows:
and as follows:
Vehicle classification
Vehicle classification 2000AADT
2000AADT
car
car 260
260
bus
bus 30
30
truck
truck 150
150
truck-trailer
truck-trailer 200
200
The anticipated traffic road is a constant 5.4% and the opening of the
The anticipated traffic road is a constant 5.4% and the opening of the
road is scheduled for 2500. An axle load survey has been
road is scheduled for 2500. An axle load survey has been
conducted and assumed that the loads are equally represented
conducted and assumed that the loads are equally represented
for each direction of traffic. Determine the total ESA and the traffic
for each direction of traffic. Determine the total ESA and the traffic
class for flexible design of pavement.
class for flexible design of pavement.

Pavement, Cont….
Pavement, Cont….
Truck-
Truck-
trailer
trailer
kg
kg
Vehicle
Vehicle
no.
no.
Axle1
Axle1 Axle2
Axle2 Axle3
Axle3 Axle4
Axle4
1
1 6350
6350 12480
12480 8490
8490 9940
9940
2
2 6450
6450 12240
12240 6290
6290 9470
9470
3
3 5550
5550 13930
13930 8550
8550 10150
10150
4
4 4570
4570 15300
15300 2720
2720 2410
2410
5
5 4190
4190 15060
15060 3110
3110 2800
2800

Pavement, Cont….
Pavement, Cont….
Truck
Truck kg
kg
1
1 6100
6100 4500
4500 7250
7250 5480
5480
2
2 5200
5200 6500
6500 8260
8260 8940
8940
Bus
Bus
1
1 5000
5000 6400
6400 4600
4600 5200
5200
2
2 2100
2100 3100
3100 3200
3200 3300
3300
Car
Car
1
1 2100
2100 4200
4200 6000
6000 2500
2500

Traffic Loading
Traffic Loading
The most important factors in designing
The most important factors in designing
pavement structure
pavement structure
Structural design factors of pavement
Structural design factors of pavement
design
design
 loading magnitude
loading magnitude
 loading configuration
loading configuration
 number of repetition
number of repetition

Three different procedure
of traffic loading
of traffic loading
1.
1. Fixed Traffic: the thickness of pavement is
Fixed Traffic: the thickness of pavement is
determined by single wheel load magnitude
determined by single wheel load magnitude
 Any wheel configuration are converted into
Any wheel configuration are converted into
equivalent single wheel load (ESWL)
equivalent single wheel load (ESWL)
 Design is performed based on the largest ESWL
Design is performed based on the largest ESWL
within all configuration
within all configuration
 Commonly used for airport and heavy-wheel load
Commonly used for airport and heavy-wheel load
but light traffic volume highways
but light traffic volume highways
 Not commonly used today
Not commonly used today

of traffic loading, Cont…
2. Fixed Vehicle: the thickness of pavement is
2. Fixed Vehicle: the thickness of pavement is
determined by the number of repetition of the
determined by the number of repetition of the
standard single axle load.
standard single axle load.
 Any axle configuration is converted to equivalent
Any axle configuration is converted to equivalent
single axle load by multiplying the number of
single axle load by multiplying the number of
repetition of each configuration by its equivalent axle
repetition of each configuration by its equivalent axle
load factor (ESAL)
load factor (ESAL)
 Design is performed based on combined effect of all
Design is performed based on combined effect of all
types of axle loads in terms of ESAL
types of axle loads in terms of ESAL
 Because of the great variety of axle load and traffic,
Because of the great variety of axle load and traffic,
it is the commonly used method today
it is the commonly used method today

3. Variable Traffic and Vehicle: the design
3. Variable Traffic and Vehicle: the design
is performed based on individual effect of
is performed based on individual effect of
each traffic and vehicle
each traffic and vehicle
 Most commonly used in mechanistic design
Most commonly used in mechanistic design
approach
approach
 No need to convert equivalent axle load
No need to convert equivalent axle load
factor
factor
 It has been used by the Portland Cement
It has been used by the Portland Cement
Association with design charts
Association with design charts

Design Period
Design Period
 The length of time that the road need to
The length of time that the road need to
be strengthened to continue its use but
be strengthened to continue its use but
not necessarily changing the whole
not necessarily changing the whole
structure
structure

Table for the design
Table for the design
period (ERA, 2001)
period (ERA, 2001)
Road classification
Road classification Design period (years)
Design period (years)
Trunk road
Trunk road 20
20
Link road
Link road 20
20
Main access road
Main access road 15
15
Gravel road
Gravel road 5
5
Other roads
Other roads 10
10

 The vehicle classification is mainly based
The vehicle classification is mainly based
on the weight of the vehicles which can
on the weight of the vehicles which can
be classified in numbers 1 to 5 by ERA
be classified in numbers 1 to 5 by ERA

Table for vehicle
Table for vehicle
classification (ERA, 2001)
classification (ERA, 2001)
Vehicle
Vehicle
code
code
Type of vehicle
Type of vehicle Description
Description
1
1 Small car
Small car Passenger car, minibuses (up to 24
Passenger car, minibuses (up to 24
passengers), taxis, pick-ups, and land
passengers), taxis, pick-ups, and land
cruiser, land rovers, etc.
cruiser, land rovers, etc.
2
2 Bus
Bus Medium and large size buses above 24
Medium and large size buses above 24
passengers
passengers
3
3 Medium truck
Medium truck Small and medium size trucks including
Small and medium size trucks including
tankers up to 7 tons load
tankers up to 7 tons load
4
4 Heavy truck
Heavy truck Trucks above 7 tons load
Trucks above 7 tons load
5
5 Articulated
Articulated
truck
truck
Trucks with trailer or semi-trailer and
Trucks with trailer or semi-trailer and
tanker trailers
tanker trailers

Initial Traffic Volumes
Initial Traffic Volumes
 This can be obtained by direct counting of
This can be obtained by direct counting of
vehicle based on the classification of vehicles
vehicle based on the classification of vehicles
and classify as the average daily traffic. Based
and classify as the average daily traffic. Based
from the value of these ADT, the AADT can be
from the value of these ADT, the AADT can be
determined by some formula used by ERA.
determined by some formula used by ERA.
The ADDT is defined as the total annual traffic
The ADDT is defined as the total annual traffic
usually summed for both direction and divided
usually summed for both direction and divided
by 365. Sometime traffic loading that is used in
by 365. Sometime traffic loading that is used in
the structural design is obtained only in one
the structural design is obtained only in one
direction.
direction.

Traffic Forecasting
Traffic Forecasting
 Attracted of diverted traffic due to the
Attracted of diverted traffic due to the
improvement of existing pavement
improvement of existing pavement
 Normal traffic growth due to the increase in
Normal traffic growth due to the increase in
number and usage of motor vehicle
number and usage of motor vehicle
 Generated traffic – traffic due to upgrading of
Generated traffic – traffic due to upgrading of
constructing the new road facility
constructing the new road facility
 Development traffic due to changes in land use
Development traffic due to changes in land use
 Converted traffic
Converted traffic

Determination of Cumulative
Determination of Cumulative
Traffic Volumes
Traffic Volumes
AADT
AADT1
1=AADT
=AADT0
0 (1+i)
(1+i)x
x
This formula is used to determine the expected traffic upon the
This formula is used to determine the expected traffic upon the
opening of the traffic.
opening of the traffic.
This formula is used to determine the expected cumulative
This formula is used to determine the expected cumulative
traffic volume over the design period.
traffic volume over the design period.
 
 
i
i
AADT
T
N
1
1
365 1




Axle Load
Axle Load
For pavement design purposes the damaging
For pavement design purposes the damaging
power of axles is related to “standard” axle
power of axles is related to “standard” axle
is 8.16 metric tons using empirical
is 8.16 metric tons using empirical
equivalency factors.
equivalency factors.
n
i
axle
EF 






8160

Axle Load Survey
Axle Load Survey
 The axle load survey is taken directly by
The axle load survey is taken directly by
weighing using the portable vehicle-
weighing using the portable vehicle-
wheel weighing device when a major
wheel weighing device when a major
highway is being designed
highway is being designed
 The survey is being undertaken in
The survey is being undertaken in
conjunction with the traffic counting
conjunction with the traffic counting
device
device

Cumulative Equivalent
Cumulative Equivalent
Standard Axle (ESA)
Standard Axle (ESA)
 Cumulative ESA acting on the design lane is the design
Cumulative ESA acting on the design lane is the design
number of standard axle load repetition used in the
number of standard axle load repetition used in the
determination of pavement thickness
determination of pavement thickness
 For two-lane road, either of both lane can be used as
For two-lane road, either of both lane can be used as
the design lane but for multiple lane the outside lane
the design lane but for multiple lane the outside lane
usually is the design lane
usually is the design lane
 The cumulative one-directional traffic volume will be
The cumulative one-directional traffic volume will be
added to determine the cumulative ESA
added to determine the cumulative ESA
 Upon determining the cumulative ESA, the traffic
Upon determining the cumulative ESA, the traffic
classes will be selected from the table given:
classes will be selected from the table given:

Traffic Classes for Flexible
Traffic Classes for Flexible
Pavement Design (ERA,2001)
Pavement Design (ERA,2001)
Traffic Classes
Traffic Classes Range (10
Range (106
6
ESAs)
ESAs)
T1
T1 <0.3
<0.3
T2
T2 0.3 – 0.7
0.3 – 0.7
T3
T3 0.7 – 1.5
0.7 – 1.5
T4
T4 1.5 – 3.0
1.5 – 3.0
T5
T5 3.0 – 6.0
3.0 – 6.0
T6
T6 6.0 – 10.0
6.0 – 10.0
T7
T7 10.0 – 17.0
10.0 – 17.0
T8
T8 17.0 – 30.0
17.0 – 30.0

Accuracy-Traffic Classes
Accuracy-Traffic Classes
 To minimize errors the guidelines set for
To minimize errors the guidelines set for
traffic counting and axle weighing should
traffic counting and axle weighing should
be done religiously
be done religiously
 For unpaved roads, T4 is the most safe
For unpaved roads, T4 is the most safe
traffic class if data are unavailable, but if
traffic class if data are unavailable, but if
there is, it should be less than 500
there is, it should be less than 500
vehicles per day in both direction
vehicles per day in both direction

Estimating Axle Load for
Estimating Axle Load for
Gravel Roads
Gravel Roads
Given below are the defaults values of ESA
Given below are the defaults values of ESA
for gravel roads
for gravel roads
Axle per heavy vehicle
Axle per heavy vehicle 2.30
2.30
ESAs per heavy axle
ESAs per heavy axle 0.20
0.20
ESAs per heavy vehicle
ESAs per heavy vehicle 0.46
0.46

Select Design Period
Estimate Initial Traffic Volume (Initial AADT) per class of vehicle
Estimate Traffic Growth
Determine Cumulative Traffic Volume Over the Design Period
For Flexible Pavement For Gravel Roads
Estimate Mean Equivalent Axle
Load per class of vehicle
Estimate the Cumulative ESA’s Over the
Design Period in One Direction
Select Appropriate Traffic Class for
Flexible Design Pavement
Select Appropriate AADT for Design
Gravel Wearing Course

Highway Engineering PPresentation-elmer2.ppt

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