Analysis on Dynamic Stability of Rock Slope in Seismic Area in Sichuan Province

A three-dimensional numerical model for rock slope of Lixian-Xiaojin highway in Sichuan province was established by FLAC3D. The seismic wave in Wenchuan earthquake on 12th May in 2008 measured at the Lixian seismic station was an 8.0 magnitude earthquake The Wenchuan earthquake was adopted to analyze dynamic stability of the slope. The calculation results show the slope was stable and the maximum value of acceleration time histories of slope face was amplified, and the range of the amplification multiple for PGA (peak of ground acceleration) is from 2.16 to 3.48. The max amplification multiple appeared around the slope middle which was the most unstable position under seismic load and permanent displacement in slope ground surface was 2.584mm ~5.141mm. Both of horizontal permanent displacement and acceleration response peak have vertical amplification effects. Furthermore, permanent displacement had 14 times amplification and acceleration response peak have 1.3 times amplification at the top of slope.