The characteristics and failure mechanism of the largest landslide triggered by the Wenchuan earthquake, May 12, 2008, China
The characteristics and failure mechanism of the largest landslide triggered by the Wenchuan earthquake, May 12, 2008, China
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汶川地震引发的最大滑坡特征及破坏机制，2008年5月12日，中国
DOI：
10.1007/s10346-011-0276-6
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发表时间：
2012-03
期刊：
影响因子：
6.7
通讯作者：
Li, Biliang1
中科院分区：
文献类型：
--
作者：
Huang, Runqiu1;Pei, Xiangjun1;Fan, Xuanmei1, 2;Zhang, Weifeng1;Li, Shigui1;Li, Biliang1
强震是滑坡的主要触发因素之一。2008年汶川地震（Mw= 7.9）引发了成千上万的山体滑坡。其中以大广堡滑坡为最大，滑坡面积7.8 km 2，最大宽度2.2 km，估算体积7.5 × 108 m3。滑坡位于四川安县映秀-北川断裂带的上盘。滑坡体移动了约4.5公里，阻塞了黄洞子山谷，形成了近600米高的滑坡坝。与研究区其他同震滑坡相比，大广堡滑坡获得了惊人的动能，强烈的开裂和变形，在滑坡后部暴露出1公里长的头部陡坎。通过现场调查，认为滑坡的发生主要受地震、地形、地质等因素的控制。滑坡的特殊位置和地形特征可能对地震动产生的地形放大作用决定了滑坡的破坏。地震对边坡稳定性的影响主要体现在两个方面：第一，地面震动会使岩体破碎，降低基底的摩擦强度;第二，地震加速度可能会导致在地震期间，在山坡上的正常（张）和剪应力的短期和阶段性的变化。根据滑坡的破坏机理，滑坡的动力学过程可分为4个阶段：（a）滑坡体后部岩体的破裂主要是由于地面震动产生的拉应力引起的，（B）由于地面震动引起的基底破碎，降低了基底的摩擦强度;（c）滑坡重力引起的大剪应力导致的坡脚剪切破坏;（d）沉积阶段。
Strong earthquakes are among the prime triggering factors of landslides. The 2008 Wenchuan earthquake (Mw= 7.9) triggered tens of thousands of landslides. Among them, the Daguangbao landslide is the largest one, which covered an area of 7.8 km2with a maximum width of 2.2 km and an estimated volume of 7.5 × 108m3. The landslide is located on the hanging wall of the seismogenic fault, the Yingxiu–Beichuan fault in Anxian town, Sichuan Province. The sliding mass travelled about 4.5 km and blocked the Huangdongzi valley, forming a landslide dam nearly 600 m high. Compared to other coseismic landslides in the study area, the Daguangbao landslide attained phenomenal kinetic energy, intense cracking, and deformation, exposing a 1-km long head scarp in the rear of the landslide. Based on the field investigation, we conclude that the occurrence of the landslide is controlled mainly by the seismic, terrain, and geological factors. The special location of the landslide and the possible topographic amplification of ground motions due to the terrain features governed the landslide failure. The effects of earthquakes on the stability of slopes were considered in two aspects: First, the ground shaking may reduce the frictional strength of the substrate by shattering of rock mass. Second, the seismic acceleration may result in short-lived and episodic changes of the normal (tensile) and shear stresses in the hillshopes during earthquakes. According to the failure mechanism, the dynamic process of the landslide might contain four stages: (a) the cracking of rock mass in the rear of the slope mainly due to the tensile stress generated by the ground shaking; (b) the shattering of the substrate due to the ground shaking, which reduced the frictional strength of the substrate; (c) the shearing failure of the toe of the landslide due to the large shear stress caused by the landslide gravity; and (d) the deposition stage.
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DOI：
10.1191/0309133302pp333ra
发表时间：
2002-06
期刊：
Progress in Physical Geography
影响因子：
--
作者：
O. Korup
通讯作者：
O. Korup
DOI：
--
发表时间：
2008
期刊：
--
影响因子：
--
作者：
Liu Tianbin
通讯作者：
Liu Tianbin
影响因子：
3.9
作者：
Chigira, Masahiro;Wu, Xiyong;Wang, Gonghui
通讯作者：
Wang, Gonghui
影响因子：
7.4
作者：
Jibson, RW;Harp, EL;Michael, JA
通讯作者：
Michael, JA
DOI：
--
发表时间：
2007
期刊：
Seismology and Geology
影响因子：
--
作者：
Chen Guo-guang
通讯作者：
Chen Guo-guang