| Landslide is one of the more frequent geological disasters,which often poses a great threat to national economy and engineering construction.Taking Wang Jia Ping No.3 landslide as an example,through field investigation,exploration and indoor geotechnical tests,this paper deeply discusses the relevant geological background of the study area and the formation mechanism of the landslide.Secondly,the transfer coefficient method and finite element numerical simulation software are used to evaluate the stability of the landslide under different working conditions in different construction stages.Finally,on the basis of the above analysis and evaluation,corresponding treatment measures are taken for the landslide,and the landslide treatment project after treatment is simulated to verify the rationality of the treatment scheme.The main research contents and conclusions of this paper are as follows:(1)Wang Jia Ping No.3 landslide is a deep medium-sized bedded loess bedrock mixed landslide.The landslide has a clear spatial form,with obvious boundary on both sides.The rear wall is high and steep,and it transitions to the middle part as a wide and gentle platform.The front part presents a slope extending on the Gao Man Beach of Xiuyan River at the bottom.A small secondary slide exists in the east part of the slide,and the west part is scoured by longterm running water,forming a steep bank with a height of tens of meters.(2)The transfer coefficient method is used to calculate the stability of each calculated section of the landslide under different working conditions,and the stability state and development trend of the landslide are analyzed and evaluated.(3)Midas GTS NX was used to simulate the II-II’ section of the landslide before and after the subgrade excavation.The simulation results and the results of the transfer coefficient method show that the engineering excavation and rainfall have great influence on the stability of the landslide,which needs to be treated.(4)According to the landslide formation mechanism and stability evaluation results,the corresponding engineering measures are proposed for Wang Jia Ping No.3 landslide,and the treatment effect is analyzed by numerical simulation.The results show that:(1)After treatment,a high stress concentration area appears at the place where anti-slide piles are arranged in the landslide body,which indicates that anti-slide piles play a full role in the treatment of landslide and effectively transmit the sliding thrust of the upper slide body to the lower stable stratum;(2)The stress concentration phenomenon and its numerical value,the range of shear strain and the displacement of the sliding body near the front sliding belt are obviously reduced compared with the control.(3)Shear force and bending moment nephogram intuitively show that the maximum bending moment is located near the sliding surface,and the maximum shear force is located in the middle of the anchoring section of the anti-sliding pile;(4)The stability coefficient of the landslide after treatment meets the requirements of relevant provisions in the specification,and the scheme is reasonable and feasible.(5)No matter from the displacement,maximum shear strain or X-direction stress nephogram,clear soil arching effect can be seen,which indicates that the anti-slide pile can bear the landslide thrust and the landslide soil existing between the piles can also give full play to its own role.Displacement soil arches are "saddle-shaped" and mainly exist in soil between piles.Strain soil arches show different degrees of "hump-shaped" distribution between piles and behind piles.Stress soil arches are mainly developed between piles and are basically similar to strain soil arches.The three types of soil arching effects show decreasing spatial characteristics in their distribution range and arching thickness. |
