Abstract
The spatial variability of soil shear wave velocity (Vs) significantly influences the results of site seismic response analysis. Based on the collected measured Vs values of silty clay in a certain sea area in China, this study divides the Vs data into one set of on-site sample data and six sets of historical data. A power function is used to establish the regression equation between Vs and depth h, and the joint prior distribution of the mean and variance for parameters a and b in the power function is derived using historical data. The joint posterior distribution of parameters a and b is obtained by applying the Bayesian formula to the on-site sample data. Using the maximum a posteriori mean values of a and b combined with the point estimation method, the mean and standard deviation of the predicted Vs values as functions of depth h are derived. The accuracy of the point estimation results is verified using Monte Carlo simulation. Compared to the Vs values predicted using only the mean values of a and b derived from on-site sample data, the Vs values predicted based on the maximum a posteriori mean values of a and b are closer to the measured Vs values. Accordingly, the results of the site seismic response analysis also align more closely with those calculated using the true Vs values.