Estimation of dam site elastic moduli using engineering seismic techniques

Estimating elastic moduli of soil and rock requires doing detailed laboratory and geotechnical studies on drilling cores. Seismic geotechniques is one of critical stages of site engineering investigation that can estimates these dynamic properties by measuring seismic wave velocities. That is because of relationship between seismic wave's velocity and elastic parameters such as Shear modulus, Bulk modulus, Young's modulus and Poisson's ratio. The purpose of this research is identifying geologic layers, determining velocity model and finally, estimating elastic moduli of site using two seismic methods, downhole and refraction. For this purpose, seismic data obtained from three boreholes and eight refraction profiles for both compressional and shear waves. Results of seismic data processing and interpretation reveal two to three geophysical layers. Finally, given to velocity values of seismic waves and density for borehole depth intervals, elastic moduli of site were calculated.

Keywords:

seismic geotechniques , downhole , refraction