四川彭州市灯杆坡滑坡变形特征及稳定性分析

作者等对"5.12"汶川地震诱发的彭州市灯杆坡大型堆积体滑坡的变形破坏特征、滑坡的过程机制及震后稳定性进行了较系统的研究。滑坡变形可分为三个区,Ⅰ区为主变形区,Ⅱ和Ⅲ区为Ⅰ区后缘开裂诱发的向两侧的塌陷;滑坡Ⅰ区和Ⅱ区为推移式滑坡,Ⅲ区为牵引式滑坡,主滑Ⅰ区为沿基覆界面的推移式滑移,后缘开裂下错,中前部挤胀开裂;降雨和地震因素对滑坡稳定性影响较大,暴雨和地震情况下滑坡体处于欠稳定到不稳定状态,其中Ⅰ区中前部存在较严重的局部稳定性问题。

Analysis on deformation characteristics and stablity of Denganpo landslide in Pengzhou city, Sichuan province

The deformation failure,evolvement mechanism and post-quake stability of the Dengganpo landslide off a large-scale accumulation body in Pengzhou county induced by WenChuan earthquake were studied from a viewpoint of a system.The landslide was divided into three zones： Ⅰ,the master deformation zone;Ⅱ and Ⅲ,the induced collapse zones made by crack of the tailing edge of Ⅰ zone.Ⅰ and Ⅲ zones were landslides caused by thrust load,but Ⅱ was a retrogressive slide.The dominating landslide,Ⅰzone was pushed to slide along the interface of bed rock and overlying stratum,and its following edge cracked and sinked,the middle and front part extruded and cracked.The rainfall and earthquake greatly influenced the stability of the landslide,which is in a less steady to unstable state when storm railfall and earthquake.There were severe local landslides in the middle and front part ofⅠzone.