四川广元市区周家坡滑坡形成机制及稳定性评价

周家坡滑坡位于四川省广元市南城区,目前局部处于不稳定状态,直接威胁城内300余户1,200余人以及环城南路过往车辆和行人安全,城内约3hm2土地被迫闲置。因此准确评价该滑坡稳定性至关重要。该滑坡由4个变形体组成,系古滑坡受建房和公路建设等工程活动影响后复活形成。滑坡所处斜坡长逾1,000m,且坡度较大,加之区域内雨季持续时间长,雨强大,持续降雨后滑体被激活。文章在分析滑坡所处地质环境条件的基础上,结合滑坡结构和变形特征分析滑坡形成机制,参考土工实验结果,采用不平衡推力传递系数法对滑坡稳定性进行评价,得出该滑坡体在天然状态基本稳定,但在饱水工况或饱水 地震工况条件下处于不稳定状态。依据上述分析评价结果,论文提出加固护坡、支挡工程、排水工程以及雨季监测等治理和防治措施。

Analysis on formation mechanism and stability of Zhoujiapo Landslide in Guangyuan City, Sichuan Province

Zhoujiapo Landslide is located in south district of Guangyuan City,Sichuan Province.There are over 1,200 people in the danger of the landslide.And some of the land which near the landslide,can not be developed.So it is very important to evaluate the stability of the landslide.There are 4 deformation masses in the landslide.It is the second activity of ancient landslide.The landslide is located in a slope that is over 1,000m and very steep.Moreover,the rainfall is so heavy in this area every summer that the landslide is induced.In this paper,based on analyzing the characteristics of geological environment of Zhoujiapo Landslide and its formation-evolution mechanism,the stability of the landslide is evaluated by using the imbalance thrust force transfer coefficient method.The result shows that the landslide is stable at natural situation,but it will be unstable when it is saturated with water or saturating water with earthquake.In this paper it also provides a reference of engineering design for the optimized treatment project,including anchoring,draining and monitoring.