3-DIMENSIONAL DYNAMIC-RESPONSE OF LINED TUNNELS DUE TO INCIDENT SEISMIC-WAVES

Formulae are developed to determine the three-dimensional response of twin lined tunnels buried in an infinite medium subjected to seismic l oadings using the method of successive reflection. The convergence of the method has been demonstrated both analytically and numerically. Th e dynamic interaction of the twin tunnels subjected to seismic waves i s investigated numerically. It is found that the three-dimensional res ponse of twin tunnels may differ significantly from the two-dimensiona l response, and that through-soil interaction between the tunnels may also be significant.