Study On Stability Analysis Of Highway Clay Slope And Treatment Of T-shaped Anti-slide Pile

Anti-slide pile is a reinforced concrete structure,which is mainly used in engineering landslide treatment,slope protection and foundation pit support.It is an important research direction to study the working mechanism and state of anti-slide pile with different sections and to optimize the section design of anti-slide pile.In this thesis,the transfer coefficient method and inverse algorithm are used to calculate the sliding force of the landslide on the upper slope of Macaozai Tunnel.On the basis of the calculation theory of internal force and deformation of rectangular anti-slide pile,the theoretical formula of internal force and deformation of T-shaped pile is derived through material mechanics and differential theory,and on the basis of the theory,a concrete example of T-shaped pile is given.Combined with ABAQUS numerical simulation analysis software,the working state of anti-slide pile in treating the upper slope of Macaozai Tunnel was simulated,and the working mechanism of traditional round pile and a new T-section anti-slide pile was studied.The numerical model established in this thesis compares and analyzes the mechanical behavior of traditional round pile and a new type of T-shaped anti-slide pile in landslide treatment.The main work and conclusions are as follows:(1)On the basis of reviewing related literatures on slope stability and anti-slide pile,this thesis briefly summarizes the current research status of slope stability and anti-slide pile treatment,and points out the shortcomings of the current research status,mainly from the number of piles distributed or from the form of piles distributed,lack of data diversity,and lack of research on the treatment effect of double-row T-shaped piles under complex geological conditions.In this thesis,the numerical simulation of T-shaped pile will be studied from various angles.(2)The sliding mechanism of slope and the principle of transfer coefficient method are described,the basic conditions of landslide generation and the sliding process are summarized,and the slide is generally divided into four stages according to its development process: the early creep deformation stage,the middle severe deformation stage,the late massive sliding stage and the late stable stage.How to determine the position and shape of sliding surface and shear strength index of sliding soil are summarized.The transfer coefficient method and inverse algorithm are summarized.(3)The traditional section,namely circular and rectangular anti-slide pile landslide treatment mechanism is theoretically explained and deduced,and the bending theory analysis,deformation and internal force calculation formula of anti-slide pile are deduced;The development process of T-shaped anti-slide pile and the optimization process of cross section are introduced briefly.On the basis of rectangular anti-slide pile,the theoretical formula for calculating the internal stress of T-shaped anti-slide pile is summarized and deduced.The calculation theory of T-shaped pile is substituted into a concrete example,and the displacement,shear force and bending moment of anti-slide pile are calculated and compared with that of rectangular pile.The comparative analysis shows that the displacement,rotation Angle,shear force and bending moment of T-shaped pile are all smaller than that of rectangular pile.(4)The causes of landslide,the development process of landslide and the characteristics of landslide are analyzed and summarized,and the residual sliding force of soil mass in the landslide is calculated by using the transfer coefficient method,and relevant conclusions are drawn.The anti-slide pile treatment scheme of Macaozai Tunnel is designed,including the pile position,pile diameter and length.(5)A numerical model was established,focusing on the study and comparison of the pile stress distribution,pile displacement,pile Angle size,bending moment and shear force of double-row circular pile and double-row T-shaped pile section anti-slide pile.It is also pointed out that T-shaped pile has some disadvantages in resisting lateral soil pressure due to the relatively small bearing area of the wing plate.It is found that the change of pile section has certain influence on the torque and shear transfer path.(6)Based on the numerical model,the working condition analysis after the tunnel excavation is added.The influence of soil disturbance on the working state and mechanical properties of round pile and T-shaped pile after tunnel excavation is studied.It is found that T-shaped pile has a larger increase value of pile body stress under soil disturbance,but it has stronger resistance ability and better safety performance than circular pile in terms of pile body displacement and corner resistance.