Geotechnical engineering involves studying and defining the behaviours of rocks and soil. It helps to know the strength of the soil and its deformation properties. The key materials in geotechnical engineering are rock, sand, clay and silt. The study uses scientific techniques and engineering principals for collection and interpretation of the physical properties of the site on which new construction is proposed.
Geotechnical engineering finds its application in planning infrastructures like the development of roads, tunnels, building and any other structure. It involves the analysis of the stability of cliffs and slopes, assessment of load-bearing capacity, numerical calculations and deformation or settlement in built structures.
Creative Analytical Lab and Consultant is a NABL accredited laboratory and certified by MoEF&CC to conduct geotechnical engineering. Our team consists of experienced professionals, experts and consultants who carry out the following services for each project:
Data Collection :- With extensive knowledge and regional experience our team assists our clients in the collecting the topography maps, geological maps, evaluation of regional geology conditions like earthquakes and faults along with the formation of soils and climate and weather data.
Geotechnical Investigation Programme :- We establish geotechnical investigation programme to study several project specifications like the type of structure, data collection, the difficulty of structure, expected ground conditions etc. the investigation programme includes groundwater sampling, identifying the number of undisturbed and disturbed soil samples, field vane shear tests, standard penetration tests (SPT), undistributed rock samples, number, mapping and depth of boreholes, soil and rock drilling and geotechnical laboratory testing programme.
Field Investigation & Sampling :- This includes drilling, soil sampling and investigations, rotary core drilling and rock sampling, standard penetration test, field vane shear test and core penetration test.
Drilling work: this is done with the help of drilling rigs which can drill any size or depth required. Rotary drilling methods are also employed in the soil or rock using different flushing media.Soil sampling and investigations: in this method, undisturbed samples are collected at certain intervals to the borehole depth termination or where the rock strata changes. Sampling, labeling, handling and transport of samples are executed in adherence to international standards and guidelines.Rotary core drilling and rock sampling: in this system drilling is done by fitting a bit at the lower end of a tube system and is rotated to feed into the rock. This helps in taking out a core sample. For this method, a flushing material is also used.
Standard penetration test (SPT): This is performed in drilled boreholes to estimate relative density, strength-deformation and consistency of soil samples. The soil samples are also used for classification purposes. Field vane shear test (VST): This test is used to determine the resistance to a rod that is forced into the soil. With the help of VST in-situ untrained shear strength of clay and fine-grained soils can be identified. However, this test does not apply to sandy or coarse-grained soil as they allow easy drainage through them. Core penetration test (CPT): This test is performed for the evaluation of effective site characterisation. This test helps in the assessment of subsurface stratigraphy of discontinued lenses, soft materials, potentially liquefiable materials like sand, gravels, silt) organic soil, strata with boulders and cobbles and dense granular fill. A cylindrical penetrometer with a conical tip is forced into the ground at a constant rate.
Geotechnical Laboratory Testing in geotechnical investigation:
Soil classification is done based on-
- Attenberg limits
- Moisture content
- Particle size distribution
- Specific gravity
- Unit weight
Determination of strength and deformation parameters is done by the following methods:
- Consolidated undrained triaxial compression test
- Consolidation test
- Unconfined compression strength
Rock strength property tests are done using the following two methods:
- Point load test
- Uniaxial compression strength test
Chemical analysis of groundwater is done by measuring the pH, chloride content and sulphate content of the water.
- Geotechnical Investigation Report
A detailed report will be prepared and provided to the client for each project. A consultation will also be given to the client along with the report.