To explore the seismic performance of horseshoeshaped
tunnel and predict the postearthquake disaster
situation of the tunnel, a case study is conducted on the Mopanshan tunnel, a
water diversion project in central Yunnan, a finite element model of rocktunnel interaction is established, and structural dynamic analysis
is conducted using nonlinear dynamic timehistory
method. Considering the uncertainty of site conditions and earthquakes,
suitable seismic intensity indices are selected for two different site
conditions. Meanwhile, considering the impact of damage parameters on the
fragility analysis of the structure, the relative deformation rate of the
section and the bending moment bearing capacity ratio are used as damage
indices respectively. The results show the following: (1) In the fragility
analysis of tunnel structures, peak ground acceleration has a low degree of dispersion
and is a more effective seismic intensity index. (2) The trend of tunnel
fragility under different damage indices is basically consistent, but when the
same damage index is used, the fragility of tunnels in softer sites is higher,
and the seismic performance deviates. Therefore, the safety of structures in
complex site should be guaranteed. (3) Under fortification conditions, the
probability of failure at each performance level of the tunnel is relatively
low, meeting the design requirements. In rare earthquakes, the probability of
failure at each level is relatively high, and the tunnel damage is relatively
severe.
DUAN Chaojie, HE Zhijia, SHI Yanke, XU Lin, MEN Wenbo, CHEN Rongguo
. Influence of Site Condition on Seismic Fragility of
HorseshoeShaped Tunnels[J]. Tunnel Construction, 2023
, 43(S2)
: 252
-262
.
DOI: 10.3973/j.issn.2096-4498.2023.S2.029
