Examination on Behavior of Existing Shield Trunk Sewers during an Earthquake

In Japan, major earthquakes such as Niigata Prefecture Chuetsu Earthquake and Great Tohoku Earthquake have frequently occurred after Southern Hyogo Prefecture Earthquake, and brought about great damages of sewage facilities. After these disasters, earthquake resistant measures of sewage facilities have been concerned and promoted. In this study, a dynamic nonlinear analysis using 3D-FE Model was performed to examine the seismic performance of trunk sewers built by the shield tunneling method and decide the earthquake-resistant measures. The oldest existing shield pipe in Yokohama City was examined successfully by a dynamic nonlinear analysis utilizing 3D-FE model. Shield pipe located in the uniformly soft ground satisfies the earthquake-proof performance requirement of Level 2. However, in the changing point of the ground, any structural member fails to satisfy the earthquake-proof performance requirement. In addition, the ground condition has great impact on the seismic performance of sewer pipeline has been identified.