Centrifuge model tests of the formation mechanism of coarse sand debris flow  

作　　者：周建 周韵鸿 LI Ye-xun WANG Zi-han 

机构地区：[1]Department of Geotechnical Engineering,Tongji University [2]Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education,Tongji University [3]The Second Engineering Company of CCCC Third Harbor Engineering Co.Ltd. [4]School of civil engineering,Hebei University of Technology

出　　处：《Journal of Chongqing University》2014年第3期77-89,共13页重庆大学学报（英文版）

基　　金：Funded by National Natural Science Foundation of China(Grant No.41272296)

摘　　要：Using the self-developed visualization test apparatus, centrifuge model tests at 20 g were carried out to research the macro and microscopic formation mechanism of coarse sand debris flows. The formation mode and soil-water interaction mechanism of the debris flows were analyzed from both macroscopic and microscopic points of view respectively using high digital imaging equipment and micro-structure analysis software Geodip. The test results indicate that the forming process of debris flow mainly consists of three stages, namely the infiltration and softening stage, the overall slide stage, and debris flow stage. The essence of simulated coarse sand slope forming debris flow is that local fluidization cause slope to wholly slide. The movement of small particles forms a transient stagnant layer with increasing saturation, causing soil shear strength lost and local fluidization. When the driving force of the saturated soil exceeds the resisting force, debris flow happens on the coarse sand slope immediately.Using the self-developed visualization test apparatus, centrifuge model tests at 20g were carried out to research the macro and microscopic formation mechanism of coarse sand debris flows. The formation mode and soil-water interaction mechanism of the debris flows were analyzed from both macroscopic and microscopic points of view respectively using high digital imaging equipment and micro-structure analysis software Geodip. The test results indicate that the forming process of debris flow mainly consists of three stages, namely the infiltration and softening stage, the overall slide stage, and debris flow stage. The essence of simulated coarse sand slope forming debris flow is that local fluidization cause slope to wholly slide. The movement of small particles forms a transient stagnant layer with increasing saturation, causing soil shear strength lost and local fluidization. When the driving force of the saturated soil exceeds the resisting force, debris flow happens on the coarse sand slope immediately.

关 键 词：coarse SAND DEBRIS flow CENTRIFUGE model tests formation mode water-soil interaction mechanism 

分 类 号：P642.23[天文地球—工程地质学]