Study On The Structure Design Theory And Stability Of The Anti-slide Piles With Pre-stressed Cables

As a new type of slope supporting structure,prestressed anchor cable anti slide pile has been widely used in engineering practice because of its unique advantages,but relative to other supporting system,the study of design calculation theory is not mature enough,theory achievement far behind in the engineering application.This paper takes the Chongqing Yubei District Metro Airport Z30 Road No.2 slope treatment project as the background and based on the summary of slope stability and anchor cable anti slide pile applied current research,and then studies the stability of No.2 slope through theoretical calculation and numerical simulation.The main content of the study and the results are as follows:(1)This paper summarized the theoretical,experimental and numerical analysis of slope stability and prestressed anchor cable anti slide pile,and emphasised on generalizing the development and present situation of the prestressed anchor cable anti slide pile reinforcement slope.(2)The actual slope stability has been simulated by using finite element software MIDAS / GTS,Anti slide pile spacing,section size and prestress parameters were selected,the influence of these parameters on slope safety factor,displacement and displacement of anti slide pile were obtained,and then the best values of the parameters were determined by the way of numerical simulation and analysis of results.(3)This paper has analyzed and calculated the stress and safety factor of the stress field,displacement field,plastic zone,supporting measures of the No.2 slope under excavation without support and four kinds of supporting schemes by using the finite difference FLAC3 D software.The results show that the maximum displacement of the slope value decreases gradually,plastic zone distribution reduced gradually,safety coefficient gradually increases with the support of the support measures enhanced,and then we can get that slope does not meet the specification requirements of the steady state under the case of excavation without support and No.1,No.2,No.3 supporting scheme while No.4 supporting scheme make the slope reach stable state of the requirements specification.(4)This paper has studied and analyzed the stability of No.2 slope in the No.4support scheme(retaining wall and anti slide pile and anchor and frame beam and cableanchor supporting)under the four kinds of different seismic peak acceleration through using finite difference software FLAC3 D.The results show that the more obvious the slope surface is,the greater the earthquake effect is;For the same monitoring point,the greater the input earthquake acceleration peak,the greater the corresponding displacement;When the propagation of seismic waves to the slope surface,the seismic acceleration is higher than that from the peak earthquake acceleration input at the bottom of the slope model;With the increase of earthquake peak acceleration,the distribution range of the plastic zone gradually increases,but the plastic zone in the four cases is not in a state of penetration;With increase of seismic peak acceleration,the safety factor of the slope is decreased gradually,but in four kinds of different seismic acceleration factor of safety than regulatory requirements,therefore,the No.4supporting scheme is in line with the requirements of the seismic stability.