Comparative Analysis of Foundation Materials Bearing Capacity Using MASW Techniques in Opolo and Amassoma, Bayelsa State, Nigeria

Abstract

The study of comparative analysis of the foundation material bearing capacity of soils in Opolo and Amassoma, Bayelsa State, Nigeria, utilized Multichannel Analysis of Surface Waves (MASW) techniques and Standard Penetration Tests (SPT). A 12-channel ABEM Terraloc Mark 6 geophone system surveyed undeveloped areas at two points in each location, spaced 70 meters apart, with 5-meter offset geophones. Borehole data from SPT revealed subsurface layers and N-values. Data processed with Easy MASW software indicated shear wave velocity profiles, showing increased soil stiffness with depth typical of Niger Delta Basin sediments. Shear wave velocities ranged from 213.71 m/s to 574.82 m/s in Opolo and 206.03 m/s to 589.68 m/s in Amassoma. Ultimate bearing capacities (Qult) from shear wave velocities ranged from 180.67 kPa to 517.09 kPa in Amassoma and 186.16 kPa to 504.06 kPa in Opolo, while allowable bearing capacities (Qa) varied from 60.22 kPa to 172.36 kPa and 62.05 kPa to 168.02 kPa, respectively. Comparative analysis indicates both locations have similar soil capabilities, suitable for medium to heavy structures. Correlation analysis between shear wave velocity and SPT-N values showed strong linear relationships (R²= 0.9047 to 0.9329), validating MASW results against traditional geotechnical methods. These findings demonstrate the effectiveness of MASW in assessing soil properties and designing foundations in the diverse geological settings of study area.