Use Of Electrical Resistivity And Multichannel Analysis Of Surface Wave Geophysical Tomography In Geotechnical Site Characterization Of Dam

Abstract

Performance of geotechnical site characterization is a primary function of geotechnical engineers. Generalizations required to extrapolate conventional geotechnical boring data can limit the effectiveness of site assessments. Advancements in geophysical technology have simplified means of data acquisition and interpretation of electrical and seismic testing, allowing a broader audience of practitioners to utilize methods for various engineering and environmental applications. In this study, electrical resistivity and multichannel analysis of surface waves (MASW) seismic geophysical methods are used to expound upon previous geotechnical sampling and in situ testing conducted at an earthen dam site in East Texas. Findings from this study show: results of geophysical testing are comparable with those from conventional geotechnical field and laboratory testing, dissimilarities between geophysical profiles and geotechnical data can exist due to soil heterogeneity, resolution capabilities and data smoothing associated with geophysical interpretation, and areas of low resistivity and low density corresponded with observations of seepage and seepage related issues.