Treatment Design Of The 2nd Landslide In Xiaohegou And Numerical Simulation Analysis

With the background of the proposed highway from Yinchuan to Baise and taking the 2nd landslide in Xiaohegou as the research object, the basic characteristics, causes and mechanism of formation is found out through data collection, field exploration and laboratory testing. On the basis, the paper calculates and evaluates the stability of the landslide. The landslide thrust and anti-slide pile design are also calculated. The specific design of the landslide treatment plan is also given out combined with the engineering geological characteristics of the landslide. Based on the treatment design, the finite element numerical simulation software Midas/GTS is used to simulate the stability of the landslide under different conditions. Conclusions are summarized below:(1)The 2nd landslide in Xiaohegou are formed by two large loess landslides. The front part of south landslide has suffered secondary slide under the effect of scouring water.(2)The stability of the landslide under two working cases is evaluated by transfer coefficient method. Under normal condition, the north landslide is in the stable state on the whole. the south landslide is currently overall stable, but the front part is a little unstable. Under the abnormal working condition, the north landslide is in the unstable state. The south landslide is unstable on the whole and the front part is easy to slide, which may result in the failure of soil mass in the back.(3)According to principles of landslide treatment design and results of landslide thrust calculation, anti-slide piles are used in the south landslide and the north part adopt the project of counterweight fill with anti-slide piles.(4)By comparing and analyzing the results of numerical simulation, the front part of the south landslide has got a very large resistance slide effect on the back section; the front part will slid under the abnormal working condition. After setting anti-slide piles the main sliding body turns into a stable state. And this effect explains anti-slide pile’s important role in improving the stability of landslide body. Soil before the piles plays a role against sliding for soil behind the piles. In the design of anti-slide piles the resistance slide effect should be considered.(5)The project of anti-slide piles of south landslide has been optimized without considering the antiskating force of soil before the piles.