Geophysical surveys measure physical properties of the ground, such as seismic wave velocity and electrical resistivity, from the surface or from boreholes. They map soil and rock layers, depth to bedrock and ground stiffness over a large area quickly and without excavation, and help decide where boreholes should be drilled.
Civitech Labs carries out geophysical surveys in Udaipur and across Rajasthan for buildings, industrial plants, substations, roads, bridges and dams.
Seismic Refraction Test (SRT)
Seismic waves generated at the surface are recorded by a line of geophones. The arrival times of the refracted waves give the P-wave velocity of each layer, the thickness of the overburden and the depth to bedrock, and help judge the rippability of rock.
Down-Hole Seismic Test (DHST)
A receiver is lowered into a borehole and waves generated at the surface are recorded at different depths. The test gives P-wave and S-wave velocity profiles with depth, used to work out dynamic soil properties for seismic and machine foundation design.
Multi-Channel Analysis of Surface Waves (MASW)
Surface waves are recorded on many geophones at once to produce a shear-wave velocity (Vs) profile of the ground. Vs values are used for seismic site classification and to assess soil stiffness.
Electrical Resistivity Test
Current is passed into the ground through electrodes and the resulting voltage is measured. Resistivity values help identify soil and rock layers and groundwater, and are used to design earthing systems for substations and plants.