The resurrection instability of old landslides is mainly based on the sliding zone soil near the base cover interface functioning as the sliding surface.Wanyuan City has large topographical fluctuations,abundant rainfall,and too many landslide events.This paper analyzes the instability process of the Maoba-zi landslide through engineering geological survey and related geological disaster monitoring methods:The primary cause of the Maobazi landslide is the excavation of the foundation pit at the front edge of the land-slide,and the excavation of the foundation pit leads to the entire slope.The stress distribution is manifes-ted as the stress concentration at the foot of the slope,the shear failure zone appears,and the landslide be-gins to creep and deform;under continuous heavy rain conditions,the groundwater level rises sharply,and the existence of tensile cracks makes rainwater easily enter the slope.The shear strength of the sliding body is reduced,and the existence of silty clay causes a larger hysteresis in the dissipation of pore water pressure.The water barrier of the bedrock causes the local uplift pressure of the slope body to support the landslide;manual excavation induces creep deformation of landslide,and accelerates the deformation un-der continuous heavy rain,which finally causes instability.
关键词
老滑坡/复活/降雨/开挖/变形特征
Key words
old landslide/resurrection/rainfall/excavation/deformation feature
维普
万方数据