岩土力学
巖土力學
암토역학
ROCK AND SOIL MECHANICS
2014年
z1期
127-132
,共6页
郝明辉%许强%杨磊%杨兴国%周家文
郝明輝%許彊%楊磊%楊興國%週傢文
학명휘%허강%양뢰%양흥국%주가문
滑坡碎屑流%运动机制%模型试验%流态化%影响因素
滑坡碎屑流%運動機製%模型試驗%流態化%影響因素
활파쇄설류%운동궤제%모형시험%류태화%영향인소
landslide-debris avalanche%movement mechanism%physical modeling%fluidization%impact factor
滑坡-碎屑流由于高速、远程的特点常常引发灾难性事故,其复杂的运动机制导致预测致灾范围非常困难。通过开展室内模型试验,研究了碎屑粒径、滑床糙率和挑坎对运动特性的影响。试验结果发现,滑坡碎屑运动距离受控于前端碎屑,且随着碎屑的粒径增大而增加,增加滑床糙率、挑坎均可使碎屑的运动距离减小。在前人研究成果的基础上结合碎屑材料的力学特性探讨了滑坡-碎屑流出现流态化的原因和高速远程机制,即高速运动中颗粒间的作用力远小于完整岩体,因此颗粒间的“黏聚力”不能维持滑坡体的整体性,同时致使滑坡体与滑床接触的过程中传递至滑坡体内部的摩阻力减少,从而导致碎屑滑坡的远程结果。
滑坡-碎屑流由于高速、遠程的特點常常引髮災難性事故,其複雜的運動機製導緻預測緻災範圍非常睏難。通過開展室內模型試驗,研究瞭碎屑粒徑、滑床糙率和挑坎對運動特性的影響。試驗結果髮現,滑坡碎屑運動距離受控于前耑碎屑,且隨著碎屑的粒徑增大而增加,增加滑床糙率、挑坎均可使碎屑的運動距離減小。在前人研究成果的基礎上結閤碎屑材料的力學特性探討瞭滑坡-碎屑流齣現流態化的原因和高速遠程機製,即高速運動中顆粒間的作用力遠小于完整巖體,因此顆粒間的“黏聚力”不能維持滑坡體的整體性,同時緻使滑坡體與滑床接觸的過程中傳遞至滑坡體內部的摩阻力減少,從而導緻碎屑滑坡的遠程結果。
활파-쇄설류유우고속、원정적특점상상인발재난성사고,기복잡적운동궤제도치예측치재범위비상곤난。통과개전실내모형시험,연구료쇄설립경、활상조솔화도감대운동특성적영향。시험결과발현,활파쇄설운동거리수공우전단쇄설,차수착쇄설적립경증대이증가,증가활상조솔、도감균가사쇄설적운동거리감소。재전인연구성과적기출상결합쇄설재료적역학특성탐토료활파-쇄설류출현류태화적원인화고속원정궤제,즉고속운동중과립간적작용력원소우완정암체,인차과립간적“점취력”불능유지활파체적정체성,동시치사활파체여활상접촉적과정중전체지활파체내부적마조력감소,종이도치쇄설활파적원정결과。
Landslide-debris avalanches always cause disastrous catastrophes because their high speed and long runout. Their complex movement mechanisms make the prediction of runout very difficult. Laboratory experiments are used to investigate some factors influencing the movement of rock fragments, including size of fragments, bed roughness and scrap. Flume tests show that the runout of rock fragments is decided by front part and increased with the increasing size of rock fragments. The runout becomes smaller when the bed roughness increasing or scrap is added. The movement mechanism of landslide-debris avalanche is also discussed based the physical properties of granular material and previous studies: the force between particles is much smaller than intact rock in high speed, so the “cohesion” of particles can not ensure the landslide maintain an fixed shape, and the friction reduces when transferred by the particles at bottom, making the result of long run out.