Seismic response and stability of rock tunnels-its history and problems today

摘要

In Japan, a lot of underground structures has been constructed and they are in service in spite of complex and poor geological conditions. On the other hand, Japan is famous for the big earthquakes resulting a huge national loss, thus the aseismic design to prevent the severe damage of structures is very important. Though many buildings and structures are designed considering earthquakes, the aseismic design of structures constructed in deep underground has not been well discussed up to now. In this paper, the historical background of aseismic design is reviewed and typical seismic damages of rock tunnels are presented. And the present situation of static and dynamic design for underground structures ranging from the cut and cover tunnels in the shallow underground to the rock tunnels in deep rock formation is presented. Then problems to establish a practical method of aseismic design for the rock tunnels is discussed.