库区堆积层滑坡地表变形规律模型试验研究

Model Tests on Surface Deformation Pattern of Colluvial Landslide in Reservoir Area

受库水位波动影响,三峡库区堆积层滑坡呈非均匀运动,其地表变形具有明显的分区特征。传统的变形监测手段(如全站仪、GPS、GNSS等)仅能实现滑坡体上重要部位少量“单点”数据采集,无法发现无监测区域的变形情况。基于物理模型试验,采用三维激光扫描技术和时空地理加权回归模型,研究了不同蓄水位高度下堆积层滑坡地表变形规律。结果表明,坡表变形云图可较为直观地展示滑坡整体的变形趋势与特征,发现肉眼及监测点外难以识别的变形现象,可作为点变形监测的重要补充。时空地理加权回归模型(GTWR)由于考虑了空间和时间的非平稳性,对滑坡坡表变形拟合效果较好。

Affected by the fluctuation of reservoir pooling water level,the movement of a colluvial landslide in the Three Gorges reservoir area exhibits the non-uniform behavior and the distinct zoning characteristics.The conventional deformation monitoring means(such as total station,GPS,GNSS,etc.)can only achieve limited point data collection at important locations on the landslide mass and cannot detect deformation in unmonitored areas.Based on the physical model test,a three-dimensional laser scanning technology and the geographical and temporal weighted regression model(GTWR)are used to study the surface deformation pattern of the colluvial landslide at different pooling water storage levels.The results show that the laser point cloud of the slope surface deformation can present the characteristics and the overall deformation trend of the landslide intuitively and find the deformation phenomenon that is difficult to be identified by the naked eye or outside the monitored area,which can be an important supplement for point monitoring.The GTWR performs well in fitting the surface deformation of the landslide slope for considering the non-stationarity of space and time.