Electrical Resistivity Imaging for Foundation Failure Investigation at Remo Secondary School, Sagamu, South-- Western Nigeria.

Subsurface investigation for foundation studies of Remo Secondary School Sagamu, Ogun State, Nigeria was carried out using a geophysical survey involving electrical resistivity imaging method. Measurement involving Wenner Configuration and vertical electrical sounding (VES) using Schlumberger array were taken along seven (7) traverses using the PASI-Earth (16GL-N) Resistivity meter. The results were presented as a pseudo section 2-D inverted Resistivity and interpreted with the Earth imager software to provide both lateral and vertical information of the study area. The geoelectric sections delineate maximum of four geologic subsurface layers comprising of the topsoil, sandy clay, clay and the coarse sand with depth to bedrock between 10m to 27m. Clayey materials were identified in some part of the study area and this is dangerous to any engineering structures in that area since expansive clay is an incompetent host material.