基于测斜仪监测成果的蠕滑体变形机制分析

ANALYSIS OF CREEP DEFORMATION MECHANISM BASED ON INCLINOMETER MONITORING RESULTS

向家坝水电工程马延坡变形体是沿特定滑面产生整体蠕滑变形的典型工程实例。基于勘探成果,布置测斜仪对变形体的内部变形进行监测,获得了良好的监测成果。在此基础上,对测斜仪变形曲线的突变进行深入分析,提出变形曲线与蠕滑变形体形态的对应关系,揭示滑动带的位置及厚度,阐明蠕滑变形机制,为工程处理措施的制定和实施提供了可靠依据。进而通过对位错–时间曲线的分析,对加固措施的作用进行说明,且对蠕滑变形体在治理后的稳定性进行评价。研究结果表明,马延坡蠕滑变形体主要受JC①夹层控制,为典型顺层滑动变形模式。在实施减载、支档和排水等综合治理措施后,滑动带位错速率减缓,边坡趋于稳定。研究工作扩展了监测成果的应用范围,对今后类似边坡的勘探、监测和资料分析具有参考意义。

The creep deformable mass of Mayan Slope, which is located at the dam site of Xiangjiaba Hydropower Station, is a typical structure-controlled integral sliding landslide. It is important to monitor deformation inside the slope, so inclinometers are disposed according to geological analysis and exploration. Based on inclinometer deformation curve obtained, the relationship between the curve of displacement-depth and geological characteristic is analyzed, and the location and thickness of the slipping zone are determined. Moreover, the mechanism of creep movement has been studied. So the corresponding reinforcement measures have been taken in time. Then, based on the displacement-time curve of slipping zone, the creep deformation trend is illustrated, and the stability condition after reinforcement is also estimated. It is found that interlayer JC（1） is the creep-controlled slipping zone with typical bedding slipping failure modes. The treatments including load-decreasing, reinforcing and groundwater-draining have greatly reduced the creep rate of speed, and the deformable mass tends to be stable. It shows that the deformations of landslide monitored by inclinometers are practicable, and it is also valuable for analogical slope-monitoring.