MATERIALS DIVISION

 The Materials Division falls under the Development Department of Ghana Highway Authority. It has representation in the Maintenance Division in the ten Regions as well as our Mobile Maintenance Units.

The core responsibility of the Division is to ensure Quality Control (QC) and Quality Assurance (QA) of on-going projects and undertakes other destructive and non-destructive investigations for distressed areas of completed Development and Maintenance projects. It also carries out research and analysis into the use of new construction materials and chemicals, to ascertain their effectiveness in the improvement of road pavement materials.

 The Division has set up a Central Materials Laboratory in Accra and undertakes in-depth investigations and research into various causes of failures in roads, structures and bridges. The laboratory undertakes QA and QC as well as commercial material testing for insitu and transported materials. There are five sections executing the responsibilities as they emerge. The section are as outlined below:

  • Soils, Aggregates and Concrete
  • Foundations
  • Pavement
  • Bituminous Products
  • Research

The Central Materials Laboratory also serves as a training field for in-house Engineers, students on vacation training as well as National Personnel.

The laboratory undertakes numerous tests on construction material for roads and bridge works, of which some are listed below:

Carry out In-Situ Density Tests, including Moisture Content Determination (Transport Extra)

Carry out In-Situ CBR Test

Carry out Plate Bearing Test

 

TEST PITS

Sinking of Test of Minimum Plan Area of 1mx 1.5m from Ground Level to a Depth not Exceeding 1.5m (Hand Dug)

Sinking of Test Pits Minimum Plan Area of 1m by 1.2m below ground level (Hand Dug) Depth exceeding 1.5m

Extra over for taking Disturbed Samples in Air Tight containers Labeling and Transporting to Laboratory

LABORATORY TEST

Determination of Moisture Content

Determination of Bulk Density, including Moisture content Determination

Sieve Analysis by Wet Sieving

Sieve Analysis by Dry Sieving

Mechanical Analysis by Pipette or Hydrometer Method

Determination of Specific Gravity

(Two Determination)

 

Determination of Plastic Limit and Liquid Limit (Atterberg Limits) Cassagrande

Determination of Plastic Limit and Liquid Limit (Atterberg Limits) Cone Penetrometer

Determination of Shrinkage Limit

Differential Free Swell

Standard Triaxial Shear Test on 0.037m diameter x 0.0760 specimen.  Undrained Quick Test without Pore pressure Measurement

Standard Triaxial Shear Test on 0.037m diameter x 0.0760 specimen.  Undrained Quick Test with Pore Pressure Measurement

Triaxial Shear Test, Drained Slow Test with Rate of Loading adjusted for negligible excess Pore Pressure in  specimen during loading (4 days)

Unconfined Compression Test on 0.0375m x 0.760m Specimens (TSR)

Director Shear Test on Undisturbed or  Re-molded circular specimens

Consolidation Test One Dimensional (7 days)

 

Permeability Test with falling Head or constant Head Permeability (2 days)

Compaction Test

Using 2.5kg

Using 4.5kg

Determination of Soaked CBR (3 point)

CBR Swell

 

TESTS ON FINE AGGREGATE

Grading

Determination of Clay, Silt and fine Dust

Determination of Organic Impurities

Specific Gravity & Water Absorption

Bulk Density

 TESTS ON COARSE AGGREGATE

Grading

Particle Shape, Flakiness Index & Elongation

Determination of Clay, Slit  & Fine Dust

Apparent Density, Specific Gravity & Water Absorption

Bulky Density

10% Fine Test

Sodium Sulphate Soundness Test (SSS)

Percentage pass Sieve DS 200

Los Angeles Abrasion

Aggregate Crushing Value

Aggregate Impact Value

 TEST ON CONCRETE

 

Mix Design

Compressive Strength test on Cubes or Cylinders (Set of 3 cubes maximum)

Compressive Strength test on Sand-crete  Blocks

 

Analysis of Hardened Concrete of Mortar to determine proportions of different ingredients

Schmidt Hammer Testing

Flexural Strength on Concrete

 CHEMICAL TESTS

Ph of Soil or Water

Determination of total Acid Soluble Sulphate content of Soil

Determination of Sulphate in ground water

Chloride content determination in Soil Water or Rock sample

 TESTS ON BITUMEN & ASPHALTIC CONCRETE

Mix Design

Moisture Sensitivity Test (TSR)

Saybolt / Universal furol Viscosity

Specific Gravity of Bitumen

Flash and Fire Point Test

Penetration Test

Distillation Test

Extraction Test

Coring through Asphaltic concrete

Marshall Test (5 Point compaction)

Maximum specific Gravity Gmm

Softening Point

Thin Film Oven Test

Rolling Thin Film Oven Test

Kinematic Viscosity

Absolute viscosity (60ºC, 100,150ºC)

Residue on Sieving

Determination of STV – Viscosity

Determination of Breaking Index

Loss of Stability Test

Compressive Strength

Determination of Air Void Content of Asphaltic Concrete Cores

Stripping test

Determination of Bulk Density of Asphaltic Concrete Cores

Determination of Marshall Stability and Flow of Asphaltic Concrete Mixes

 

CORING THROUGH CONCRETE

Coring Plain concrete 100mm Thick

Coring Plain concrete 150mm Thick

Coring Plain concrete 200mm Thick

Coring Plain concrete 300mm Thick

Coring Reinforced concrete 150mm Thick

Coring Reinforced concrete 200mm Thick

Coring Reinforced concrete 300mm Thick

RESILIENT MODULUS TESTING

Resilient Modulus of asphalt (Cores/Briquettes)

DESCRIPTION

Resilient Modulus of Soil

NON DESTRUCTION TESTS

Falling Weight Deflectometer (FWD) Test

Roughness Measurement