Material Testing and Field Compliance Test
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Transcript of Material Testing and Field Compliance Test
Material Testing and Field Material Testing and Field Compliance TestCompliance Test
Universal Rural Roads Access ProgramTraining of Trainers for Contractors
02 – 07 August 2013, Chancho
Ethiopian Roads Ethiopian Roads AuthorityAuthority
Presentation OutlinePresentation Outline
Background
Need for Testing and Specification
Material Laboratory Testing
Field Compliance Test
Test data management & QC
BackgroundBackground
Road formation
◦Site clearance◦Earth work/ embankment
construction◦Subgrade construction◦Subbase and ◦Surfacing
Engineered natural surfaces
Typical gravel road cross section
Embankment/SubgradeEmbankment/SubgradeMaterial quality Requirements for
borrow material, Earth work for embankment and subgrade construction
The material used in embankment, sub-grade, 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) Cut and Fill (Embankment) SectionsSections
Granular SubbaseGranular SubbaseGravel 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 SpecificationNeed 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. 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 Contractor’s Responsibilities from the view of the provision of the the view of the provision of the ContractContractGeneral ResponsibilitiesThe 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.
……contcontClause 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.
……contcontClause 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.
……contcont3202 MATERIALS FOR EMBANKMENTSa) 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.
……contcontSERIES 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 TestingLaboratory Testing
Basic testing requirements – Soils
◦Atterberg limits (LL, PL)◦Linear shrinkage◦Particle size distribution – grading ◦Moisture content and compaction◦California Bearing Ratio (CBR)
UnsuitableUnsuitable soil materials for soil materials for subgradesubgrade
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 Desirable Properties of Soil as Subgrade MaterialSubgrade 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 SubbaseGranular SubbaseGrading limits
Grading Modulus
Plastic Index, PI
Compaction requirements
CBR
Gravel wearing surfaceGravel wearing surfaceBased on
◦Shrinkage product (linear shrinkage)◦Grading Coefficient
Atterberg LimitAtterberg Limit
Casagrande LL Device PL Device
Plastic index
PI = LL - PL
Phase Solid Solid statestate
Semi-Semi-solid solid statestate
Plastic Plastic statestate
Liquid Liquid statestate
SuspensioSuspensionn
Water
Limits
Shrinkage
Constant volume
Condition
Hard to soft
Workable Sticky
Slurry Water-held
suspension
Shear strength [kN/m2]
Negligible to Nil
Moisture content
Soil phases and Soil phases and Atterberg limitsAtterberg limits
Dry soil
Shrinkage limit
Plastic limit
Liquid limit
0 SL PL LL
Sticky limit
Plastic indexPlastic index
Water content increasing
Volume increasing
Shear strength decreasing
(~1.7)(~170)
PI
Particle Size DistributionParticle Size Distribution
Particle Size DistributionParticle Size DistributionGradation
◦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 States of soil aggregate mixturesmixtures
Alemgena Alene, PhD CENG6305 – Ch2
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 compact
Not difficult to compact at right moisture level
a) no fines b) enough fines c) excess fines
Purpose of soil Purpose of soil classificationclassification
Development of soil Development of soil classificationclassification
Basis of soil classification Basis of soil classification systemssystems
Key soil components in soil Key soil components in soil classification systemsclassification systems
Extension of USCS for LVRExtension of USCS for LVR
Comparison AASHTO and USCS (Lia Comparison AASHTO and USCS (Lia 1970)1970)
Comparison of soil classification Comparison of soil classification systemssystems
Material Classes for Pavement Material Classes for Pavement formationformation
ERA Testing StandardsERA Testing Standards
Differences in Test Differences in Test MethodsMethods
Differences in Test Differences in Test MethodsMethods
Differences in Test Procedure - Differences in Test Procedure - CBRCBR
Rationale for SpecificationRationale for Specification
Specs and Use of Local Specs and Use of Local MaterialsMaterials
Appropriateness of current Appropriateness of current specsspecs
Use of local materialsUse of local materials
ERA Low Volume RoadsERA Low Volume RoadsMaterial 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 TestConcrete TestConcrete grade shall be
confirmed at least through strength test
Field Compliance TestsField Compliance Tests
Field density – Sand cone replacement
Strength – Dynamic cone penetrometer
Dynamic Cone Penetrometer (DCP)Dynamic Cone Penetrometer (DCP)
• How to do test
• How to analyse data
• How to calculate Structural Number
· 60° INC
Ø 20mm
Key:-1 Handle2 Hammer (8kg)3 Hammer shaft4 Coupling5 Handguard6 Clamp ring7 Standard shaft8 1 metre rule9 60° cone
7
8
9
5
4
9
1
2
3
6
Dynamic Cone Penetrometer
100
10
50
5
15 50 100101
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)
DCP (mm/blow)
CB
R (
per
cent
)
4
2
1
3
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
DCP TEST
Site/road:Test No:Section No/Chainage:Direction:Wheel path:
Zero reading of DCP:Started test at:
Date:
No.Blows Blows mm No.
Blows Blows mm No.Blows Blows mm
DCP TestDate:_______________________
Site/Road Addis Ababa - GohatsionTest No._______________________Section No.Chainage 115+000 RHS
Zero reading of DCP: 100
Direction:________________________
Started test at: Subgrade
Wheel Path: ______________________
No.Blows
∑Blows
mmNo.
Blows∑
Blowsmm
No. Blows
∑Blows
mm
1 150
1 180
1 210
1 230
1 250
1 265 1 280 1 295 1 315 1 330 1 340 3 345 5 350 5 355
10 360 10 362 10 362
Alemgena Alene, PhD CENG6302 - Ch6
100
0
200
300
400
500
600
700
800
900
1000
1100
1200
40 80 120 1600D
epth
(m
m)
Number of blows
RoadbaseThickness 266 mm
CBR 41 per cent
Sub-baseThickness 380 mm
CBR 20 per cent
Gravel surfacingThickness 220 mmCBR >100 per cent
SubgradeCBR 13 per cent
Typical DCP result