Material Testing and Field
Compliance Test
Ethiopian Roads Authority
Universal Rural Roads Access Program
Training of Trainers for Contractors
02 – 07 August 2013, Chancho
Presentation Outline
 Background
 Need
for Testing and Specification
 Material
 Field
 Test
Laboratory Testing
Compliance Test
data management & QC
Background

Road formation
◦
◦
◦
◦
◦
Site clearance
Earth work/ embankment construction
Subgrade construction
Subbase and
Surfacing
Engineered natural surfaces
Typical gravel road cross section
Embankment/Subgrade

Material quality Requirements for borrow
material, Earth work for embankment and
subgrade construction

The material used in embankment, subgrade, shoulders, etc. shall be soil, gravel, a
mixture of these or other material
approved by an Engineer. It shall be free
from logs, stumps, roots, rubbish, etc.
Cut and Fill (Embankment)
Sections
Granular Subbase

Gravel material to be used for sub-base shall
be obtained from approved sources in
borrow areas, cuts or existing pavement
layers.

The complete sub-base shall contain no
material having a maximum dimension
exceeding two-thirds of the completed layer
thickness.

Gravel Sub-base material shall, unless
otherwise stated, conform to specification
requirements in terms of:
Need for Testing and Specification

Material testing is essential to verify material characteristics
for application trials, detect defects, analyze failures, improve
new materials or conduct basic research.

The materials used in construction projects must meet strict
quality regulations, standards, and service life requirements.

The materials will affect the quality, costs, sustainability and
environmental impact of the construction project.
…. cont
•
The technical staff involved in testing areas should have
educational certificate and work experience.
•
The Engineer shall verify that the laboratory has the
appropriate equipment, calibration and verification
records, test procedures, and trained personnel to
perform every procedure in the proposed scope.
•
Test procedures shall be performed with applicable
materials
Contractor’s Responsibilities from the view of
the provision of the Contract
General Responsibilities

The Contractor has obligation with respect to the
supply of materials and workmanship.

Do the work with care and skill in a proper and
workmanlike manner;

Use materials of good and viable quality;

Ensure that both the work and the materials should
reasonably fit for the purpose they are wished-for.
…cont
 Clause 8.1
The Contractor shall, with due care and diligence,
execute and maintain the works and provide all
labour, including the supervision thereof, materials.
Construction plant and all other things, whether of a
temporary or permanent nature, required.

Clause 36.1
All materials and workmanship shall be of the respective kinds
described in the Contract and in accordance with the Engineer’s
instructions, and shall be subjected from time to time to such tests
as the Engineer may direct at the place of manufacture of
fabrication, or on the site or at such other places as may be
specified in the contract.
…cont
 Clause 36.2.
All samples shall be supplied by the Contractor at his own
cost if the supply thereof is clearly intended by or
provided for in the contract.
 Clause 36.3.
The Cost of making any test shall be borne by the
Contractor if such test is clearly intended by or provided
for in the contract.

Material Standards to be Met on
Completion of Construction
The Specification sets out materials standards to be met by
each major construction material tested in the Site
laboratory.

1209
Specifications
American, British and Ethiopian standards are used in this
Technical Specification. In the absence of any definite
provisions in the Specification on any particular issue,
reference may be made to the latest codes of AASHTO,
ASTM, BS or Ethiopian standards in this order of
precedence.
…cont
3202 MATERIALS FOR EMBANKMENTS
a) Fill
 The following soils are unsuitable for construction of embankments:
 •Materials with more than 5% by weight of organic materials
 •Materials with a swell of more than 3%
 •Clays with plasticity index over 45 or a liquid limit over 90.
b) Improved Subgrade
 The following are minimum requirements for fill materials to be
used in area of weak sub-grade:
 •Minimum 25% passing 2.36 mm sieve.
 •Ip less than 30.
 •Reject index less than 10%
 •Soils shall be non-expansive, non-dispersive and free from any
deleterious matter.
…cont
SERIES 4000: CULVERT AND DRAINAGE WORKS
 Concrete cube strength
 aggregate
 water
5102 Gravel Wearing Course
 The minimum requirements for gravel wearing course
material
 Maximum size (mm)
 Oversize Index (Io)
 Shrinkage product (Sp)
 Grading coefficient (Gc)
 Soaked CBR (at 95% Mod AASHTO)
 Treton Impact Value (%)
Laboratory Testing

Basic testing requirements – Soils
◦
◦
◦
◦
◦
Atterberg limits (LL, PL)
Linear shrinkage
Particle size distribution – grading
Moisture content and compaction
California Bearing Ratio (CBR)
Unsuitable soil materials for
subgrade

Clay soil which contains the value of Liquid Limit
more than 80% and/or Plasticity Index more than
55%,

It is flammable materials (oily), and organically clay
soil,

Contain lots of rotten roots, grass and other
vegetation,

Soil which is soft and unstable because it is too wet
or dry which makes it difficult to compact properly.
Desirable Properties of Soil as Subgrade
Material
Stability.
 Incompressibility.
 Minimum changes in volume and stability
under adverse condition of weather and
ground water.
 Permanency of strength.
 Good drainage.
 Ease of compaction.

Granular Subbase

Grading limits

Grading Modulus

Plastic Index, PI

Compaction requirements

CBR
Gravel wearing surface

Based on
◦ Shrinkage product (linear shrinkage)
◦ Grading Coefficient
Atterberg Limit
Casagrande LL Device
Plastic index
PI = LL - PL
PL Device
Soil phases and Atterberg limits
Phase
Solid state
Semi-solid
state
Plastic
state
Liquid
state
Suspension
Water content increasing
Water
Limits
Dry
soil
Shrinkage
limit
Plastic Sticky
limit
limit
Liquid
limit
Plastic index
Shrinkage
Constant
volume
Condition
Hard to soft
Shear
strength
[kN/m2]
Moisture
content
Volume increasing
Sticky
Workable
Slurry
Shear strength decreasing
0
(~170)
(~1.7)
SL
PL
Water-held
suspension
Negligible to Nil
PI
LL
Particle Size Distribution
Particle Size Distribution

Gradation
◦ Poor/ Uniform
◦ Well/ continuous
◦ Gap graded
If there are a lot of different fractions between the
largest and the smallest, the sample is well graded.
If only a few sizes can be seen, the sample is single
sized or poorly graded. Single-sized materials do
not compact well, because there are no suitably
small-sized particles to fill the empty voids between
the bigger particles a good mechanical interlock
States of soil aggregate mixtures
a) no fines
b) enough fines
c) excess fines
High stability when
confined
High stability when
confined
High stability when
confined AND dry
No cohesion
High cohesion when dry
High cohesion when dry,
low when wet
High angle of internal
friction
High angle of internal
friction
No angle of internal
friction when wet
Not affected by moisture
conditions
Moderately affected by
moisture conditions
Greatly affected by
moisture conditions
Very difficult to compact
Moderately dificult to
Not difficult to compact at
Alemgenaright
Alene,moisture
PhD
compact
level
CENG6305 – Ch2
Purpose of soil classification
Development of soil classification
Basis of soil classification systems
Key soil components in soil classification
systems
Extension of USCS for LVR
Comparison AASHTO and USCS (Lia 1970)
Comparison of soil classification systems
Material Classes for Pavement formation
ERA Testing Standards
Differences in Test Methods
Differences in Test Methods
Differences in Test Procedure - CBR
Rationale for Specification
Specs and Use of Local Materials
Appropriateness of current specs
Use of local materials
ERA Low Volume Roads

Material requirements for roadbase
◦ A wide range of materials including
 lateritic,
 calcareous and quartzitic gravels,
 river gravels and other transported and residual
gravels, or
 granular materials resulting from weathering of
rocks can be used successfully as road base
materials

Particle size distribution for natural gravel
base
Concrete Test

Concrete grade shall be confirmed at
least through strength test
Field Compliance Tests

Field density – Sand cone replacement

Strength – Dynamic cone penetrometer
Dynamic Cone Penetrometer (DCP)
•
How to do test
•
How to analyse data
•
How to calculate Structural Number
1
K
e
y
:
1 H
a
n
d
l
e
2 H
a
m
m
e
r
(
8
k
g
)
3 H
a
m
m
e
r
s
h
a
f
t
4 C
o
u
p
l
i
n
g
5 H
a
n
d
g
u
a
r
d
6 C
l
a
m
p
r
i
n
g
7 S
t
a
n
d
a
r
d
s
h
a
f
t
8 1
m
e
t
r
e
r
u
l
e
9 6
0
°
c
o
n
e
2
Dynamic Cone Penetrometer
3
4
5
6
Ø
2
0
m
m
7
9
8
9
·
6
0
°
I
N
C
1. Kleyn and Van Heerden, 1983 (60° cone)
2. Smith and Pratt, 1983 (30° cone)
3. Van Vuuren, 1969 (30° cone)
4. TRRL, 1990 (60° cone)
CBR (per cent)
100
50
10
5
3
4
1
2
1
1
5
10
50
DCP (mm/blow)
1. Log10 (CBR) = 2.632 - 1.28 Log10 (mm/blow)
2. Log10 (CBR) = 2.555 - 1.145 Log10 (mm/blow)
3. Log10 (CBR) = 2.503 - 1.15 Log10 (mm/blow)
4. Log10 (CBR) = 2.48 - 1.057 Log10 (mm/blow)
DCP - CBR RELATIONSHIP
100
DCP TEST
Site/road:
Test No:
Section No/Chainage:
Direction:
Wheel path:
No.
Blows Blows mm
Date:
Zero reading of DCP:
Started test at:
No.
Blows Blows mm
No.
Blows Blows mm
DCP Test
Date:_______________
________
Site/Road Addis Ababa Gohatsion
Test
No._______________________
Section No.Chainage
115+000 RHS
Zero reading of DCP:
100
Started test at:
Subgrade
Direction:________________________
Wheel Path:
______________________
No.
∑
Blows Blows
mm
1
150
1
180
1
210
1
230
1
250
1
265
1
1
1
1
1
3
5
5
10
10
10
280
295
315
330
340
345
350
355
360
362
362
No.
∑
Blows Blows
mm
Alemgena Alene, PhD
CENG6302 - Ch6
No.
∑
Blows Blows
mm
Number of blows
0
40
80
120
160
0
100
200
Roadbase
Thickness
266 mm
CBR
41 per cent
300
Depth (mm)
400
500
Sub-base
Thickness
380 mm
CBR
20 per cent
600
Gravel surfacing
Thickness 220 mm
CBR
>100 per cent
700
800
900
1000
Subgrade
CBR 13 per cent
1100
1200
Typical DCP result