基于变形分区确定某反倾岩质岸坡变形体锁固段

DEFORMATION ZONING BASED DETERMINATION METHOD FOR LOCKED SEGMENT OF DEFORMABLE BODY IN BENDING ROCK BANK SLOPE

对处于蠕滑阶段的边坡而言，准确确定蠕滑段和锁固段是进行稳定性评价及演化趋势预测的基础和前提。以我国西南山区某水库型岸坡变形体为例，在综合分析岸坡工程地质条件的基础上，通过联合运用野外现场地质调查、地表位移监测、钻孔、平硐、深部位移监测、物探等多种勘察手段，查明了岸坡的结构特征，并分别对岸坡进行地表和深部变形分区。在此基础上，结合当前稳定性现状，划分出岸坡蠕滑段与锁固段。结果表明：（1）岸坡在河谷下切过程中发生了弯曲倾倒变形，弯曲折断面深度为20～80m；（2）岸坡前部为蠕滑段，中部为锁固段，后部为拉裂段，具备滑移一拉裂一剪断“三段式”发育特征。研究结果可直接用于该岸坡变形体的稳定性评价，且对于同类型处于蠕滑阶段边坡的勘察手段及综合分析具有一定的借鉴意义。

To the creeping slope,accurate determination of creep segment and lock segment is the basement of stability evaluating and evolution trend predicting. This paper examines a deformable body of bending rock bank slope in southwest mountainous of China. The examination is based on the comprehensive analysis on the slope engineering geological conditions. The field investigation, ground displacement monitoring, drilling, adit,underground displacement monitoring and geophysical prospecting are used to detecting the structural characteristics of the bank slope. Then,the ground and underground deformation zoning is taking to the slope. The present stability status is examined. The locked segment and creeping segment are divided accordingly. The results show the follows.( 1) The bank slope has occurred bending and toppling during the river bed scour. The depth of bending fractureplane is between 20 m and 80 m.( 2) Creeping segment is located in middle-anterior and posterior of the slope. The locked segment is located in the middle of the slope. These results can be used to stability evaluating of these slopes. They have some reference meaning to investigation method and comprehensive analysis of other creeping slopes.