Correlation of geoelectrical and geotechnical parameters of data obtained from geophysical survey conducted at Ahmadu Bello University Phase II, Zaria, Nigeria

Abstract

Vertical electrical soundings (VES) and standard penetration test (SPT) were carried out at Ahmadu Bello University Phase II, Zaria, Nigeria, with the aim of correlating between transverse resistance (T) and number of blows per counts (N-value) for foundation studies. Two (2) SPT and VES using Schlumberger electrodes array, were conducted within the study area. The VES data acquired from the field were processed and interpreted using AGI earth imager 1D software. Borehole data of exact point, where the VES was carried out were used for calibration. The results obtained from the VES depicts that the depth to basement values ranges between 6.5 and 8.0 m which agree with the borehole data obtained from the SPT results. The results of resistivities and thickness obtained from the VES curve were used to compute transverse resistance. The transverse resistance was used to correlate with the N-values obtained from SPT data. It was observed that the correlation of transverse resistance and N-value was linear and highly positive. The linear relationship that was established between the two parameters can be used to determine the soil strength at any point within the area of study.