Seismic design and performance of tunnels and underground structures

Although recent earthquake events (e.g. Kobe 1995, Duzce 1999, Chi-Chi 1999, Wenchuan 2008) have demonstrated that underground structures and tunnels may undergo extensive deformations or even collapse, their seismic response has not been adequately explored compared to aboveground structures, due to lack of well-documented experimental data and field evidence. In this regard, design specifications in modern seismic codes are based primarily on simplified methods, the implementation of which may lead to substantially different seismic design for underground structures. Along these lines, the Research Unit of SDGEE expertise regarding tunnels and underground structures covers the following areas:

• Investigation of the seismic behaviour of circular tunnels and box-type structures
• Experimental and numerical modelling of the seismic behaviour of embedded structures
• Seismic design of pipelines (gas, water, waste water), tunnels and metro stations
• Vulnerability assessment of tunnels and underground structures
• Evaluation of seismic design methods
• Site and structure specific studies for pipelines, metro lines and underground structures