2015年7月11日浙江绍兴太平山村滑坡灾害研究

2015年7月11日23时，受前期连续降雨和灿鸿台风短时强降雨影响，浙江省绍兴市太平山村滑坡在2000年首次发生滑动变形基础上，再次出现剧烈的变形迹象，前缘土体明显隆起，滑坡边界急剧扩大，直接威胁到下方约25幢居民住户的生命财产安全。本文在地表裂缝、滑坡表面位移及坡体深层水平位移监测基础上，结合详细的地质调查、现场工程地质测绘、含水率及渗透试验等手段，对太平山村滑坡的基本特征进行了分析，并形成了滑坡形成机制及破坏模式的初步认识。结果表明：（1）滑坡平面形态呈圈椅状，主滑方向约140，滑坡体斜长约330m，前缘宽150～180m，后缘宽度约75～105m，厚15～25m，体积105104m3，以残坡积和坡洪积含碎石粉质黏土层为主；（2）强降雨是诱发滑坡体失稳变形的主要因素；（3）滑坡基本呈蠕动变形状态，滑动速度缓慢，仅在强降雨条件下出现依次明显的错动，一般时期内基本保持稳定状态，可以判定为牵引式滑坡。

INVESTIGATION ON CATASTROPHIC LANDSLIDE OF JULY 11, 2015 AT TAIPINGSHAN,SHAOXING COUNTY,ZHEJIANG PROVINCE

On July 11, 2015, by the early continuous rainfall and short-term heavy rainfall caused by the Chan Hung Typhoon, a large landslide occurred on the basis of first sliding during the year of 2000 in Shaoxing county, Zhejiang Province. The front of landslide swelled significantly and the landslide boundary expanded rapidly. Life and property safety of about 25 households in front of the landslide were threatened. The crack, surface displacements and deep horizontal displacements monitoring were examined in this paper. Such examinations were combined with site geological investigation, site engineering geological survey, site moisture content test and permeability test. The characteristics of the landslide and the formation and failure mode of the landslide by preliminary understanding were analyzed. The results show that:(1) the plane form of the landslide was shaped like a chair and the main slide direction was about 140nd the plagioclase was about 330meters long and the front and trailing edge were 150~180 meters and 75~105 meters wide, respectively, and the volume was 105104m3 and the landslide was made of eluvial and alluvial silty clay with gravel; (2) heavy rainfall is the major factor in inducing the sliding deformation; (3) the landslide is substantially in state of creep deformation and slides slowly and will remain steady state within the general period, which can be determined for the tractive landslide.