贵州福泉滑坡冲击水塘的涌浪过程分析

Dynamic analysis on the catastrophic landslide and related impulse water waves in Fuquan,Guizhou,China

2014年8月27日20∶30左右,贵州福泉突发灾难性山体滑坡灾害,致使两个村庄受灾,23人死亡。滑坡失稳后,滑体沿140°方向高速剪出,冲击坡脚深水塘激起涌浪,产生的高压水波裹挟滑坡碎屑沿滑坡路径西侧越过小山包,淹没新湾村民小组3户居民房屋,部分滑坡碎屑运动40 m破坏了小坝村民小组。为了对贵州岩溶山区灾害易发地区潜在的类似滑坡灾害预测防治提供依据,本文运用DAN-W软件反演了滑坡入水前的运动参数和几何形态,并利用FLUENT软件对滑坡碎屑入水产生的涌浪及其传播过程进行了模拟分析,结果表明:滑坡前缘在9.2 s时开始入水,滑坡启动后21.7 s时涌浪水波裹挟滑坡碎屑冲向对岸,模拟结果与现场调查基本吻合。

At about 8：30 p.m. on 27 August 2014, a catastrophic landslide occurred in Fuquan, Yunnan, southwestern China. This landslide and related impulse water waves destroyed two villages and killed 23 people. After the landslide initiation, the slide mass ran down rapidly toward the direction of 140 （ and the main part of the displaced materials plunged into a water-filled quarry below the source area and resulted in an impulse wave of muddy water and rock debris. The wave ran up the opposite slope on the western side of the runout path and overwhelmed three homes in the Xinwan village. Part of the displaced materials travelled a horizontal distance of about 40 m from its source and destroyed the Xiaoba village. To provide information for hazard zonation of similar type of potential landslides in the same area, a combined landslide-wave simulation is carried out in this paper. The DAN-W model is used to simulate the landslide propagation before entering the quarry, while FLUENT is applied to simulate the impulse wave generation and propagation after entering the quarry and output data from the DAN-W simulation of the landslide before entering the quarry are used as input parameters for wave modelling. The results shows that the sliding mass began entering the quarry at 9.2 s and 21.7 s after the landslide initiation, the impulse wave and trapped rock debris ran up the opposite slope at an elevation of 1 280 m amsl, respectively. Very good agreement between the observed and simulated results of the landslide propagation has been achieved. It is worth noting that locations affected by recordable waves according to the simulation correspond to those ones recorded by field investigation.