Geotechnical Lab Testing
Soil classification
- Mechanical grain size analyses (sieves)
- Hydrometer testing
- Atterberg limits
Consolidation testing
- 1D consolidation using odoemeter (dead weight) equipment (3 units)
- 1D consolidation using pneumatic consolidometer (3 units)
- 3D isotropic consolidation using triaxial cell under constant rate of strain (1 unit)
Triaxial testing
- 50 mm and 70 mm diameter cohesive samples can be tested under CD or UU conditions, with either volumetric change or pore water pressure measurement
- Unconfined compressive strength of cohesive samples
- Hollow torsional cylinder tests on reconstituted cohesionless samples for determination of CSSM parameters
Hydraulic conductivity
- Constant head permeameter for cohesionless samples
- Flexible wall permeameter for clay samples
Rock core testing
- Point Load testing
- Unconfined compressive strength
Gallery
Cohesive Soils
Undisturbed samples of cohesive soils can be retrieved using Shelby Tube samplers or, as shown in the picture, by cutting block samples. In this case, the deposit in question has been recently excavated near a temporary shoring wall.
Block Sample
Block sample in the lab, prior to trimming.
Soil Lathe
The soil sample is carefully reduced to a cylindrical shape by shaving the block in a soil lathe.
Triaxial Pedestal
The specimen is set onto the triaxial pedestal, and enclosed with the rubber membrane.
Load Testing Frame
The load testing frame with the assembled triaxial cell, where the sample is conditioned prior to triaxial shearing.
Shear Band
Triaxial specimen shows the typical shear band after failure.
Multiple Shearing
This specimen, obtained from a Shelby tube sample, exhibit multiple shearing or failure planes.
Soils testing in different directions
Using block sampling, soils specimens can be produced to test soils in different directions. As shown here, soil specimens can be tested in the direction perpendicular or parallel to the sedimentation plane. This is useful to investigate anisotropic properties of cohesive soils, as well as observing the effect of layering in the soil response to loading.
Sliced Shelby Tube
A Shelby tube sample is sliced to expose the layering structure, in this case a typical varved clay specimen.
CD and CU Triaxial Conditions
In the case of cohesionless soils, reconstituted specimens can be tested under consolidated-drained (CD), or consolidated-undrained (CU) triaxial conditions. At In-Depth laboratory, we have equipment to test hollow cylinders of sand under axial and torsional loading conditions. This type of test allows us to investigate the responses of a sand specimen under complex stress paths, as well as to evaluate the effects of stress-induced anisotropy on granular material.
Determining soil classification properties and indices
We also offer soil testing services to determine soil classification properties and indices, such as grain size distribution; Atterberg Limits, specific gravity, index parameters (Dmax and Dmin); void ratios; moisture contents; and bulk densities.