Seismic Isolation of Tunnel Lining - A Case Study of the Gavoshan Tunnel in the Morvarid Fault in IRAN

摘要

Strike slip faults are more wide spread around the world than the other kinds of faults. Therefore,rnhuge structures such as dams, tunnels and power plants are more likely to meet these faults. When thernfault is active, special treatment should be considered. In order to analyze the shape and amount ofrnfault rupture effect on tunnel lining, it was necessary to build an accurate tunnel model. This casernstudy concerns Gavoshan tunnel in west of Iran, which is a twenty kilometers, horseshoe shaped,rnwater supply tunnel by 4.2 meters diameter. The tunnel crosses the Morvarid fault, which is an activernstrike slip. The Tunnel is modeled by Finite Element Method, using ANSYS software. First, the faultrnrupture has imposed and failure zone in lining and rock is calculated. In the second step, liningrnisolation is achieved by considering a gap between lining and rock mass. The last step is filling therngap with rubber-based material and study the effect of this material over lining behavior duringrnearthquake. Finally, a suitable solution and some comments for the protection of lining in seismicrnzone are suggested.