Statistical Estimation of Soil Parameters in from Cross-Plots of S-Wave Velocity and Resistivity Obtained by Integrated Geophysical Method

Cross-plots of S-wave velocity and resistivity obtained by geophysical methods statistically estimated geotechnical soil parameters, Fc, D20, blow counts, and the soil types, of levee body and foundation for Japanese levees. The S-wave velocity and the resistivity were collected from surface wave methods and resistivity methods respectively. Total survey line length of the geophysical methods was about 670 km on 40 rivers in Japan. The Fc, D20, blow counts, and soil types were collected from about 400 boring logs carried out on geophysical survey lines. S-wave velocity and resistivity at the depth of the blow counts were extracted from two-dimensional geophysical sections. The total number of extracted data, blow counts and soil type, was about 4000. The data was grouped by levee body and foundation. A polynomial approximation estimated the soil parameters from S-wave velocity and resistivity. A least squares method optimized the coefficients of the equation. Accuracy of the estimation was statistically evaluated by comparing estimated and actual soil parameters. The correlation coefficients between estimated and actual parameters ranged between 0.43 and 0.8. The polynomial approximations with the optimized coefficients calculated soil parameter sections from S-wave velocity and resistivity sections.