Introducing a New Method for Ground Structure Estimation using Microtremor Array Observation Technique

Abstract

Ground structure characteristic is an important parameter in seismic site effect evaluation for earthquake structural design. Many geophysical methods can be used to estimate ground structure. The best field measurement option that requires least field effort and yet producing accurate estimation is the main concern of this study. This study applies microtremor array observation method to investigate the accuracy of dispersion curve estimated using Centerless Circular Array (CCA) methods of 5m radius. The dispersion curve observed was assessed by comparing to theoretical dispersion curve generated from proposed shear wave velocity (VS) profile of sites. The observed dispersion curve shows good agreement with theoretical dispersion curve over a wide frequency range, which is ranging from 3 -10 Hz. This segment of dispersion curve can be utilized to estimate ground structure by means of inversion of dispersion curve. CCA method is capable to be used to estimate ground structure in term of VS profile.