Dynamic Soil Properties for Construction Site Investigation Using Geophysical Methods

Abstract Geophysical approaches are used for site characterization to determine the dynamic behaviour of soil. Structures built on a site without sufficient assessment are prone to collapse or failure. Thus, before beginning any building activity, it is critical to assess the soil dynamic qualities. This is significant because buildings are constructed on top of the ground surface, supported by the underlying soil and rock. This work aimed to determine a competent layer for building foundations. This study was conducted to evaluate the dynamic soil behaviour of Paya Terubong on Penang Island. Resistivity, Young's modulus, shear modulus, Poisson's ratio, bulk modulus, bulk density, rippability, and material bearing capacity are among the parameters utilised for the characterization. This will be obtained from the electrical resistivity, seismic refraction, and MASW methods. Three layers were detected by these methods. Results from the study indicate that the area is mostly composed of highly dense silty sand and granitic bedrock, which makes it competent for foundation construction since higher compaction raises the ultimate and allowable bearing capacities of the third layer to very high levels. In addition, soil and rock layers identified using geophysical methods match well with the borehole data showing that material stiffness increases with depth. Rippable layers extend from the ground surface to a depth of 3 meters. The calculated values gotten from the soil dynamic properties and material bearing capacity show that the second and third layers have good geotechnical qualities. The ultimate bearing capacities calculated for the first layer range from 453 to 731 kPa, while the second layer capacities range from 1041 to 1691 kPa, and capacities for the third layer range from 2013 to 3650 kPa. For setting up structures, the second layer can support building foundations at a depth of 4 meters from the existing ground level. This approach is cost-effective, saves time, and is non-destructive for site characterization.