護岸構造物の振動特性について

Abstract

Mycrotremor observation has been performed for fifteen quaywall structures in the port ofOsaka during these five years. Each structure has been selected as it has a typical structural type.Predominant frequencies of these structures are estimated by means of spectral analysis. Theestimated first predominant frequency is nearly close to the natural frequency of surfacial groundobtained by the multiple reflection theory. The damping coefficient is also estimated by means ofan identification theory based on the autoregressive moving average time series. The results giveseveral facts that the damping coefficient of surfacial ground is arround the several tens percent, andthat the damping coefficient of quaywall structure is about several percent.