Abstract
In order to study the dynamic behaviour of underground pipelines, the earthquake observation has been continued on an underground pipeline since 1977. Out of over twenty earthquakes observed since the installation of instruments, the Miyagiken-Oki earthquake, the Izuhanto-Tohooki earthquake, and the Chibaken-Chubu earthquake were taken up as examples. A closer investigation by evolutionary spectra analysis and phase velocity analysis was made to make clear the relation between the strain measured on the underground pipeline and the ground motion.
The method of the seismic response analysis of underground pipelines was proposed taking account of the results of above-mentioned earthquake observation. To prove its effectiveness, the strains obtained by using this method were compared with observed ones. In result was proved the effectiveness of this seismic response analysis method.
