Abstract
A mapping of shear-wave velocity for all of Japan is performed using “Japan Engineering Geomorphologic Classification Map (JEGM)” which has been developed as a GIS-based ground condition map. At first, we calculate the average shear-wave velocity in the upper 30m (AVS30), which is a simple and useful predictor for estimating site amplification factors of peak ground velocity (PGV), for approximately 2,000 sites where shear-wave velocity has been measured in all over Japan. Geomorphologic units for all boreholes logging data are interpreted using landclassification maps that are the base paper maps for the JEGM. Next, we examine the correlation between not only geomorphologic units but also geographical information derived from the JEGM and the AVS30 values. The AVS30s show some dependency with altitudes, slope gradients, and distances from mountains or hills. In order to develop the estimating model of the AVS30, multivariate regression analysis is conducted using these geomorphologic indices. Then, we can achieve to create an AVS30 map with relatively high accuracy for all of Japan using JEGM.
