Comprehensive Correlations Between the Geotechnical and Seismic Data Conducted via Bender Element

Bender element (BE) is a useful seismic tool to predict the geotechnical soil properties using empirical correlations. However, there were uncertainties in the correlation equations which were not discussed in detail. In this study, the seismic data was thoroughly investigated to improve the correlations with the physical soil properties. Several proportions of sand–kaolin mixtures were compacted, sheared, as well as BE tested. The results showed curve relationships whereas the highest seismic wave velocity and the highest shear strength were attained at the proportion of 40% fine content. At this point, the void ratio, intergranular void ratio, maximum dry density, and specific gravity were 0.43, 1.43, 1.79 g/cm³, and 2.585 respectively. In addition, a direct positive linear relationship between the seismic wave velocity with cohesion (c) and shear strength (τ) provided highest values of seismic velocities at 53.7 kPa and 81.7 kPa of c and τ respectively. However, the seismic wave velocity less significant effected by the friction angle. The paper presented 68 empirical correlation equations between the previous parameters. The comparison with previous researchers indicated that the application of the empirical correlation equations was limited to the material type (clay and sand), fine content range (20–70%), void ratio range (> 0.43), and condition of the samples.