INFLUENCE OF INITIAL WATER CONTENT ON SANDY DEBRIS FLOW STARTING PROCESS
ZHOU Jian1，2，GAO Bing2，ZHANG Jiao3，JIA Mincai1，2
(1. Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education，Tongji University，Shanghai 200092，China；2. Department of Geotechnical Engineering，Tongji University，Shanghai 200092，China；3. School of Civil Engineering and Transportation，Shanghai Technical College of Urban Management，Shanghai 200432，China)
Abstract：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 water content on the sandy soil flow starting process. Based on landslide type debris flow starting process，precise measuring instrument matrix suction is used to measure variation relation of soil cohesion with water content，and pore water pressure gauge is used to measure the performance of pore water pressure during rainfall process. Using software GeoDog，the sandy soil displacement field is analyzed before it turns to debris flow；and the relation of water-soil interaction on the slippery fracture is confirmed. By researching the macro damage state and the slippery fracture position of different initial water contents sandy soil，the influence of water content on the sandy soil flow starting process is revealed.
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2012, Vol. 31 
