中文摘要：

超前冲击气浪是高速滑体运动过程中强烈推挤压缩周围的空气所产生。它具有强大的破坏能力,在运动路径上,对滑体前方的建筑物及人民生命财产常造成毁灭性灾难。以典型高速滑坡为原型,运用空气动力学理论,采用计算流体力学软件,建立了二维粘性、不可压缩、定常流模型,再现仿真了高速滑坡超前冲击气浪产生流场的特征,分析了其形成的动力学机理。结果表明：滑坡高速下滑中产生的超前冲击气浪压力与滑体的形态密切相关。滑体前部、尾部壁面倾角越大,滑坡外流场冲击气压越大。直立壁面滑坡体在前方500 m以内产生的冲击气浪压力相当于11～12级风力的破坏能力;翼型滑坡体产生的气浪压力最小,前方100 m以外对建筑物的破坏能力已较小,相当于6级风力。从而得出超前冲击气浪潜在威胁的范围和破坏作用的强度,为超前气浪灾害的防治提供了科学依据。

英文摘要：

Rock avalanches are commonly preceded by a strong blast of air.As a result of the huge volumes of material involved and long distances traveled,the major threat of rock avalanche to lives,properties and environment comes from its preceding airblast being capable of exerting enormous impacts on objects in the runout path.It lifts roofs off houses or buildings,breaks off trees and bowls them ahead of it,scours soil and colluvium,hurls rocks and wood splinters through the air,spatters mud up trees and rolls people along the ground or lifts them high in the air as the autumn wind whirls fallen leaves.This preceding blast of wind acted powerfully only in the direction in which the rock masses shot forward,but that laterally it was entirely insignificant,so the substantial damage caused by a rock avalanche is often beyond the limits of distal debris;besides,its velocity was so great in the track that as it shot out from ahead of the displaced mass detached from the slope,a powerful airblast can carry blocks of rock to cross the narrow valley and impact the opposite slope with subsequent upstream and downstream surging and run up,fall back,and finally run back up the source slope before coming to rest.In mechanism,the airblast was attributed to air pressure rise in front of a fast-moving avalanche,and its movement can be described by the model of viscous,incompressible,steady flow of aerodynamics theory.So three models of the slide bodies on slip surface with different shapes are established and the characteristics of flow field surrounding the bodies are simulated by the software for numerical hydrodynamics,Computational Fluid Dynamics.It is showed that the airblast is controlled remarkably by the shape of slide body,the larger obliquity of walls of leading edge and rear edge of slide body,the greater of the airblast pressure.Within 500 m in front of the slide body with leading edge of vertical wall,the intensity of devastating airblast pressure is equivalent to 11～12 wind pressure;whereas the airblast caused by the