新店子滑坡分析及稳定性评价

The mechanical analysis and stability evaluation of Xindianzi landslide

新店子滑坡是位于 10 8国道广北段 K1 4 + 6 0 0 处的一个古滑坡体 ,纵向长 180 m,横向宽约 12 0 m (平均值 ) ,平均厚约 30 m,总体积近 6 5万 m3。在边坡开挖修建 10 8国道后 ,由于嘉陵江对滑坡体前缘的不断冲刷 ,导致滑坡体前缘高陡部分出现拉裂缝。如果该滑坡复活 ,将严重破坏 10 8国道的交通 ,并且破坏坡顶的高压输电线路。为对滑坡进行有效的处治 ,必须首先搞清楚滑坡的成因机制。经过对滑坡详查勘探 ,查清了滑坡形成的地质背景、滑坡的物质组成以及滑带的基本特性。通过地质力学方法对滑坡成因机制进行分析 ,在此基础上利用极限平衡方法 ,采用安全系数和破坏概率对该滑坡天然状态及不利组合条件下的稳定性进行了评价 ,同时对防治措施进行了初步分析 ,为选择治理设计方案提供了重要的依据。

Xindianzi landslide is an ancient landslide which lies on the north sector of GuangYuan 108 nation's road.The landslide is 180 m long,120 m wide (average value),and 30 m thick(average value).The total volume of landslide is approximately 6500000 m 3.After road construction,the tension crevices are developed on the front of cliff because of the JiaLing River's erosion.It will destroy the communications of 108 nation's road and the power transmission network on the top of the slope if the landslide falls down.So a detail geological investigation has been carried out.An analysis of the sliding mechanism,structure of the slide mass and the properties of the sliding zones brings to light that the old slides mass will be break down in a disadvantageous situation.On the basis of formation mechanism analysis,using the methods of limit equilibrium and the damage probability,the authors calculated and evaluated the stability of Xindianzi landslide under the natual state and adverse conditions,and initially analyzed the prevention cure step.The important geologic basis for selecting project design has been provided.