Geotechnical Soil Testing in Chennai

Basic soil investigation with one bore hole and SPT typically costs ₹8,000–₹15,000. A comprehensive 3-bore investigation with full lab analysis costs ₹25,000–₹45,000 depending on boring depth and tests required.

SBC stands for Safe Bearing Capacity — the maximum load per unit area that your soil can safely carry without shear failure or excessive settlement. It is the fundamental input for foundation design. Using the wrong SBC can result in an over-designed (costly) or under-designed (dangerous) foundation.

For residential buildings (G+1, G+2), boring is typically done to 6–10 meters. For taller buildings or areas with known deep soft strata (like Velachery marine clay), boring may extend to 15–20 meters to properly characterize all soil layers.

Yes. IS 1904:1986 ("Code of Practice for Design and Construction of Foundations in Soils") mandates that the safe bearing capacity of soil must be determined before foundation design. CMDA building plan approvals for G+1 and above typically require a soil investigation report.

This is risky. Soil can vary significantly within a small area — a 50-meter gap can mean the difference between hard murrum and soft clay. This is especially true in Chennai's heterogeneous urban landscape where old tank beds, stream channels, and filled areas exist in close proximity.

SPT (Standard Penetration Test) is a borehole-based test that measures soil resistance at depth using blow counts. It gives N-values used to estimate bearing capacity. The Plate Load Test (PLT) is conducted at the surface at the actual intended foundation level — it directly measures settlement under load and gives SBC more accurately for shallow foundations.