中文摘要：

沟谷型剧动式滑坡以其启程剧动、高速短程、灾害链生效应等特点在深切峡谷地区具有极高的潜在风险。以拉月滑坡为例,基于滑坡堵江动力学过程,首先分析沟谷型滑坡的变形破坏机制与灾害链成灾模式,将拉月滑坡灾害链全过程概括为：节理化边坡地震降雨协同劣化→倾倒拉裂模式下变形发展→剪出口锁固段破裂牵连坡体高位剪出→碰撞解体并碎石流化→刨蚀河床并阻塞堆积→堰塞堵江。然后针对沟谷型滑坡堵江灾害高速短程的特点,提出滑坡强度（规模、速度和滑距）为堵江灾害的主控因素,而水沙运动规律则为影响因素。在此基础上,采用层次分析法确定各致灾因素的权重作用,并建立沟谷型滑坡堵江危险性判别模型表达式。最后通过典型案例计算表明,该模型较好地反映了沟谷型剧动式滑坡堵江的特点,对今后沟谷山区工程建设所遭遇的滑坡堵江灾害预测和风险调控,防灾减灾具有指导意义。

英文摘要：

High-speed rocky landslide has a great potential risk in the deep-cutting gorges by its unique characteristics,i.e. high speed but short travel distance,disaster chain effect,high potential energy. This paper,based on kinematics of Layue landslide-damming process,firstly concluded the failure mechanism of rocky high speed landslide occurred in gully terrain. And then analyzed its disaster chain effect,which could be outlined as follows：quake-rainfall coupled degradation of slope stability,rock slide in a topple-pull apart model,brittle rupture of the locked path,rock avalanche,riverbed ploughed and thither slope uplifted,blocking and dammming. Given the trait of high speed but short travel distance, this paper formulated that it＇s the landslide intensity（volume,velocity,runout） determins the occurance of landslide-damming disaster while river features perform as influential factors. Eventually,based on the analytic hierarchy process to highlight the factors‘ weight function,this paper established the gorge-type high-speed short-runout landslide damming hazard evaluation model. Two case studies have shown that this hazard model can fairely well reflects the effect of rocky high-speed landslide damming disaster chain in deep-cutting gorges. Moreover,such model has a great significance and instructions for future mountainous engineering risk control and disaster prevention and mitigation.