泥石流启动过程中水土作用机制的宏细观分析  

MACRO-MESO ANALYSIS OF WATER-SOIL INTERACTION MECHANISM OF DEBRIS FLOW STARTING PROCESS

作　　者：高冰[1] 周健[1,2] 张姣[3] 

机构地区：[1]同济大学岩土及地下工程教育部重点实验室,上海200092 [2]同济大学地下建筑与工程系,上海200092 [3]上海城市管理职业技术学院土木工程与交通学院,上海200432

出　　处：《岩石力学与工程学报》2011年第12期2567-2573,共7页Chinese Journal of Rock Mechanics and Engineering

摘　　要：利用自制小比例模型槽,结合可控降雨强度的降雨模拟器,进行人工降雨诱发泥石流的室内模型试验,着重研究不同降雨强度对砂性泥石流启动下滑过程的影响。利用精密的基质吸力测量仪器(PF-Meter测量仪),对非饱和砂土基质吸力随含水量的变化关系进行研究。利用孔隙水压力量测技术,对降雨过程中孔隙水压力的变化进行测量。通过水土作用的力学变化规律对泥石流启动时的宏观影响因素进行分析。在宏观分析的基础上,利用CCD微观摄像技术,观测砂土内部砂颗粒的运动规律,运用GeoDip软件从细观的角度对泥石流堆积土体力学变化的成因进行探讨。分析结果表明砂土在雨水作用下,砂颗粒的运动是导致堆积土体内部力学变化的主要因素。Using the self-developed small-scale model flume, combined with the controllable intensity, artificial rainfall simulator, the experiment of debris flow induced by artificial rainfall is carried out to study the influence of rainfall intensity on debris flow starting progress. Based on molar heat capacity principle, precise measuring instrument PF-Meter is used to measure variation relation of matrix suction with water content; and pore water pressure gauge is used to measure the performance of pore water pressure during rainfall process. Based on the water-soil interaction mechanism combining with the changes of pore water pressure and matrix suction, the macro influencing factors of debris flow are analyzed. Using the CCD camera and software GeoDip, motion characteristics of sand particles in sandy soil and water-soil interaction mechanism of debris flow are both studied from microscopic view, which indicate that the motion of sand particle under the action of rain is the main influencing factor of water-soil interaction mechanism during the starting process of debris flow.

关 键 词：工程地质 泥石流 砂土 土水相互作用 细观机制 

分 类 号：P642[天文地球—工程地质学]