库水波动下堆积层滑坡稳定性研究

堆积层滑坡是三峡库区中最常见的地质灾害类型。库水位的不同变化速率对滑坡稳定性影响显著。以三峡库区凉水井滑坡为例,分析了±0.2、±0.4、±0.6、±0.8、±1.0、±1.2、±1.4、±1.6、±1.8和±2.0 m/d 10种速率下,0.01、0.1、1和10 m/d 4种不同饱和渗透系数的堆积层滑坡在库水上升和下降过程中的稳定性变化规律。在此基础上提出了针对堆积层滑坡的三峡库区水位调度风险等级划分方案,认为库水位升降速率小于0.6 m/d为低风险,在0.6 m/d与0.8 m/d之间为中风险,大于0.8 m/d为高风险。利用实际库水位变动获得的安全系数曲线结合地质灾害等级划分方法,直观地显示了凉水井滑坡长期风险过程。研究结果对于滑坡的监测预警和水库调度具有一定的应用价值。

Research on the colluvial landslide stability during reservoir water level fluctuation

Colluvial landslide is a very common geological disaster in the Three Gorges Reservoir Area. Changes of water level in different rate significantly influence on landslide stability. Taking the Liangshuijing landslide as an example, the stability of the colluvial landslide were analyzed with ten rates between 0.2 to 2.0 m/day and four different saturated permeability coefficients of colluvial landslide in the process of water rise and drawdown in the reservoir. Based on which, the risk grading scheme of the water level regulation was put forward for the colluvial landslide in the Three Gorges reservoir area,taking v < 0.6 m/day as a lower risk, and 0.6 m/day < v < 0.8 m/day as a medium risks, and v > 0.8 m/day as a high risk. Using the safety coefficient curve calculated under the real fluctuation of water level in the reservoir and the method combined with the geological disaster hierarchies, the long-term risk of landslide process curve was shown intuitively. The results have certain application values for landslide monitoring and warning and reservoir scheduling in Three Gorges Reservoir Area.