四川泸定6.8级地震地质灾害调查

Investigation on Seismic Geological Hazards of the Luding,Sichuan M_(S)6.8 Earthquake in 2022

2022年9月5日四川泸定6.8级地震发生后,防灾科技学院组织现场科考工作组,对震中附近泸定县和石棉县地震地质灾害进行调查。调查结果表明:震中位于青藏高原向四川盆地过渡带,属于高山峡谷区域。地震诱发的地质灾害点成带状分布,展布于大渡河两岸和鲜水河断裂两侧,方向与发震断层一致,表现为数量多、范围广和人数伤亡多的特点。边坡坡面陡峭,岩体风化程度高,颗粒破碎。滑坡多以表层堆积体溜滑为主,切割深度不大。地震滑坡掩埋路基、冲击桥梁、对隧道洞口区域造成破坏。建造于边坡附近建筑物,一要注意半挖半填地基稳定性,二要留足基础底面外缘至坡顶边缘的水平距离。

After the Luding,Sichuan M_(S)6.8 earthquake occurred on Sep.5,2022,a field scientific research team of the Institute of Disaster Prevention was organized to investigate the seismic geological disasters in Luding County and Shimian County near the epicenter.The investigation results show that the epicenter of the Luding earthquake is located in the transition zone from the Qinghai Tibet Plateau to the Sichuan Basin,and it is a mountain valley area.The seismic geological disaster spots are distributed in strips on the banks of Dadu River and along the both sides of Xianshuihe Fault,with the same direction as the seismogenic fault,which are characterized by largeness in number,width in range,and heavy casualties.The slope surface is steep,the rock mass is highly weathered,and the particles are broken.Landslides are mainly caused by the sliding of surface deposit,and the cutting depth is not large.The landslide buried the subgrade,impacted the bridge,and damaged the tunnel portal areas.So for buildings built near the slope,it’s suggested that the stability of the half cut and half fill foundation should be emphasized and the enough horizontal distance from the outer edge of the foundation bottom to the edge of the slope top should be secured.