滑坡涌浪的三维SPH方法模拟及其工程应用  

A SPH based numerical method of landslide induced impulse wave and its application on Huangtian landslide event

作　　者：石传奇 安翼[1] 杨家修[2] 

机构地区：[1]中国科学院力学研究所,流固耦合系统力学重点实验室,北京100190 [2]中国电建集团贵阳勘测设计研究院有限公司,贵阳550081

出　　处：《中国科学：物理学、力学、天文学》2015年第10期52-60,共9页Scientia Sinica Physica,Mechanica & Astronomica

基　　金：长江科学院开放研究基金(编号:CKWV2012305/KY);国家自然科学基金(批准号:11372326);国家重点基础研究发展计划(编号:2014CB04680202)资助项目

摘　　要：滑坡涌浪是一种严重的次生地质灾害.滑坡体与水体的强耦合作用以及非线性水波演化是其核心特点.本文基于Navier-Stokes方程和光滑粒子动力学(SPH)离散方法,建立了能反映上述特点的滑坡涌浪产生过程的数值模型,并将其应用于复现小湾荒田滑坡涌浪事件,模拟了其三维涌浪产生的全过程,得到了符合实际观测结果的首浪参数.通过对涌浪近场特征的分析表明,常见的V形河谷中,涌浪首浪的形成受地形影响显著,可传播的涌浪波幅远小于冲击产生的首浪,传统的二维或半无限空间三维模型可能明显高估远场的涌浪高度.Landslide induced impulse wave, which is the result of high speed impact of sliding mass into water, is a serious subsequent geological hazards. Its key features are the coupling effects between water and landslide mass during the impact process and the subsequent nonlinear wave evolution in complex boundaries. Classical numerical models, e.g. shallow water equation based models, would encounter many difficulties when dealing with these features. This paper employed the Smoothed Particle Hydrodynamics method to simulate the initial stage of the landslide induced wave by solving the Navier-Stokes equation, which avoids the most of those difficulties. The slide mass is considered as rigid body while the interaction between it and the water is calculated directly. Monaghan＇s experimental data are used to validate this model and a good agreement is observed. Then the model is used to study the initial wave and evolution in Huangtian landslide event. The complete three-dimensional evolution of the wave initial stage is obtained and the simulated initial wave height is close to the observed record. Analysis of detailed near field wave characteristics shows that： the generalized near field zone could be divided into three subzones： the impact zone, the evolution zone and the propagating zone; the formation and magnitude of the initial wave are strongly constrained by topography in the deep V channel of mountain reservoirs. The namely initial wave will propagate along the impact direction and consume its energy on the opposite shore, while the energy of the waves which propagate along the river is much smaller. Thus, the amplitude of the near field waves which propagate along the river should be used to estimate the far field wave height instead of the namely initial wave. The commonly used classical two-dimensional or infinite half-space model, which use namely initial wave height as the key factor, could result notable overestimation of the wave amplitude.

关 键 词：滑坡涌浪 光滑粒子动力学 流-固耦合 非线性水波 荒田滑坡 

分 类 号：P642.22[天文地球—工程地质学]