大型岩质水库滑坡复活变形过程的影响因素分析

鉴于识别处于复杂环境下的滑坡体变形影响因素是目前滑坡变形机理研究的重点。以三峡库区木鱼包滑坡为例,基于监测数据识别出滑坡变形的阶跃段,统计得出阶跃段往往出现于高库水位阶段,约在175.0～165.0m之间波动。应用格兰杰因果检验得出库水位高程变化将导致滑坡阶跃段的出现,并进一步以Geo-Slope模拟实际库水位波动与不同库水位变化速率下滑坡稳定性的变化。结果表明,木鱼包滑坡的阶跃段出现与稳定系数下降段相对应,均处于库水位的高水位阶段,且库水位处于172～175m时滑坡稳定性系数将接近最小值,确定了滑坡复活变形的影响因素是高库水位阶段。研究成果对滑坡的复活变形机理研究及防灾预警均具有重要意义。

Influencing Factor Analysis of Large Rock Reservoir Landslide during Reactivation Deformation Process

To identify the influencing factor of landslide in complex environment is the key point of research on landslide deformation mechanism. Taking Muyubao landslide in the Three Gorges Reservoir region as an example, the"step segments of landslide deformation was identified based on the analysis of monitoring data. The statistics show that the "step segments" usually occur in the stage of high reservoir water level from 175.0m to 165.0m. Granger causality test finds that the elevation change of the reservoir water level will lead to the emergence of the landslide "step segments", and further Geo-Slope is used to simulate the landslide stability changing with the fluctuation of the actual reservoir water level and different reservoir water level change rate. The results show that the "step segments" of Muyubao landslide corresponds to the decrease of the stability coefficient, and they are all in the high reservoir water level stage. It is determined that the high reservoir water level is the influencing factor of the resurrection deformation, and the landslide stability coefficient is close to the minimum when it is between 172-175 m. The research results are of great significance to the study of the reactivation deformation mechanism of landslide and the disaster prevention.