Geophysical Investigation of Road Failure in Federal College of Education (Technical) Asaba, Delta State, Nigeria Using Electrical Resistivity Imaging (ERI) Method

Abstract: The study investigates the causes of road failure at the Federal College of Education (Technical). Asaba, Delta State, Nigeria using the Electrical Resistivity Imaging (ERI) method, a non-invasive approach to delineate subsurface features responsible for road failures. Surveys were conducted along failed road segments to characterize subsurface materials, moisture zones, and the depth to competent strata. Schlumberger array configuration was used to investigate the geotechnical causes of persistent road failure within the area. The research aimed to delineate subsurface geoelectric layers, identify weak zones, and assess their contribution to pavement instability. Five vertical electrical sounding (VES) stations were established along the failed road segments using an ABEM Terameter SAS 1000. The apparent resistivity data were processed and interpreted using RES2DINV and Surfer software to generate sounding curves and geoelectric section. The results revealed three to four distinct geoelectric layers: topsoil (50-300Ωm), lateritic layer (150-3502 m), clayey/silty layer (38-9952m), and weathered basement/high resistivity (470-900Ωm). The low-resistivity clayey/silty layer beneath the lateritic cap at depths of 5.8 m was identified and indicates the presence of weak zones, clay-rich formations, and high moisture content that contributes to pavement failures due to high plasticity in the study area. The Pseudo section results revealed that the road structure is founded on a near homogeneous substratum, indicating that the road is not situated on a better geology. Hence, the study concludes that geophysical techniques such as ERI are effective tools for subsurface characterization and can significantly reduce premature pavement deterioration in roads construction. Keywords: Road Failure, Resistivity, Schlumberger Array, Characterization, Geoelectric, layers, , Zones, Substratum. Title: Geophysical Investigation of Road Failure in Federal College of Education (Technical) Asaba, Delta State, Nigeria Using Electrical Resistivity Imaging (ERI) Method Author: Ojih Victoria Bolanle, Alade Moses Aiyeoribe, Attoh Vivian Anulichukwu, Nuhu Aliyu Tafida International Journal of Novel Research in Physics Chemistry & Mathematics ISSN 2394-9651 Vol. 13, Issue 1, January 2026 - April 2026 Page No: 46-51 Novelty Journals Website: www.noveltyjournals.com Published Date: 30-April-2026 DOI: https://doi.org/10.5281/zenodo.19939650 Paper Download Link (Source) https://www.noveltyjournals.com/upload/paper/Geophysical%20Investigation%20of%20Road%20Failure-30042026-2.pdf