An Estimation Method of Shear Wave Velocities and Damping Ratios in Soil Layers Using Forced Vibration Test Data

摘要

PURPOSE: A method for calculating a shear wave velocity and a damping ratio of the ground using the forced vibration test data is provided to remarkably improve a demerit of a conventional dynamic test method by finding out a single test value suitable to the numeric analysis through the correction of the test value for many dispersed ground properties. CONSTITUTION: A free filed ground is numerically modeled in order to propagate a wave freely. A frequency response of the dynamic responses measured on round surface is found out. To get the same value as the frequency response calculated from the numeric model of the free field ground, the ground property of the numeric model is optimized by using a gene algorithm. Finally, a stiffness coefficient and a ground damping ratio on the ground are estimated economically.