Study on the disaster effect and prevention countermeasures of landslide in Zhouqu fault zone

Zhouqu is one of the areas with the most serious landslide disasters in China, in which the fault zone landslide are frequent and the harm is huge. Based on the comprehensive remote sensing, deformation monitoring and field investigation, this paper studies the reactivation characteristics and disaster-causing mode of fault zone landslide, and puts forward the prevention and control countermeasures. The results show that: (1) the landslide in the fault zone is mainly in a strip shape and dustpan shape; The sliding body and sliding bed are generally composed of slate, phyllite and rubble, and the sliding zone soil is pebbly clay; The landslide has the characteristics of multi-level and block activity, and the differential sliding characteristics of different blocks are significant; Landslide is generally slow sliding and has fluidity characteristics; Landslide has the characteristics of rainfall sensitivity, and the response of deep landslide to rainfall has obvious lag. (2) the disaster modes of landslides in fault zone are mainly creep, tension crack effect and impact push effect in the process of slow sliding, river blocking and flooding effect, extrusion erosion effect and social impact effect after sliding. (3) the landslide conditions are large and the treatment measures are difficult to get together. However, its sudden nature is not strong, so it should focus on management and prevention. The recommended prevention measures are land use control, monitoring and early warning, risk avoidance and relocation, and engineering treatment measures are not recommended.