Investigation and assessment on mountain tunnels and geotechnical damage after the Wenchuan earthquake

Abstract

On May 12, 2008, a strong earthquake with a magnitude of 8.0 (Ms) struck Wenchuan town, in the eastern Sichuan area of west China. Following the earthquake on May 18, the Southwest Jiaotong University organized a damage survey team and dispatched it to the affected area for the investigation into the damage and collection of information and data. This paper outlines the findings of this investigation on the earthquake disaster to mountain tunnels and geotechnical engineering. The systematic investigation, involving geological conditions, design documents, construction and maintenance records of the tunnels, has been conducted and the degree of damage to investigated tunnels has been assessed according to the width and length of cracks, the stability of the slope above the tunnel, and the condition of the groundwater inrush. The results show that the major damage of the mountain tunnels was mainly concentrated in the tunnel portals due to widespread landslides and rockfalls, and the inner part of investigated tunnels suffered moderate damages mainly due to fault displacements. It is hoped that the information shared herein could enhance the outstanding of seismic behavior of mountain tunnels and improve seismic design and construction procedures. damage investigation, wenchuan earthquake, mountain tunnels, ground failures

Shaking table tests of tunnel linings in progressive states of damage

“…Tunnel linings are often shown to be partly cracked following strong vibrations and there is an increased interest in identifying the complex damage mechanisms. For example, following the 2008 Wenchuan earthquake, over 30 tunnel linings were reported to have cracked with different types of cracks found in almost all the tunnel linings (Wang et al, 2009). It was found that longitudinal cracks observed in some tunnels developed and extended along the whole tunnels.…”

Model test study on the dynamic response of the portal section of two parallel tunnels in a seismically active area

“…On May 12, 2008, a violent earthquake struck Wenchuan town and destroyed many tunnels to various degrees in the region, and the tunnel damage in the portal section was particularly serious (Wang et al, 2009). So, the dynamic response of underground structures to earthquakes emerges as significant research direction.…”

Nonlinear response and reliability analysis of tunnels under strong earthquakes

“…During the Kobe earthquake in Japan in 1995, underground structures, such as the Daika subway station, were destroyed severely (Nishiyama, Kawama, & Haya, 2004), while in 1999 during the Chichi earthquake in Taiwan, 49 out of 57 mountain tunnels were destroyed to some extent (Wang et al, 2001). In 2008, during the Wenchuan earthquake in China, 56 tunnels were damaged and required retrofitting (Wang, Gao, Jiang, & Yuan, 2009). Subsequent investigations and analyses revealed that the damages of the pertinent tunnels related closely to the geotechnical conditions of the surrounding soil -rock deposits.…”