Stability Analysis Of High Slope Supported By Frame Prestressed Anchor Rod Based On Anchor Rod Prestress Loss

As a new type of support system,the frame prestressed anchor support structure began to be gradually developed and applied in the 1980 s.It mainly combines the advantages of prestressed anchors and concrete frames,and is a flexible support structure.Slope stability analysis has always been an important research topic in the field of geotechnical engineering.In engineering practice,with the construction and development of railways,highways,airports,docks,embankments,and earth-rock existing projects,these fields have been involved There are a large number of slope engineering problems,but the prestress loss of the frame prestressed anchor cable needs to be further improved.Therefore,the research on the prestress loss of the frame prestressed anchor cable has important theoretical and practical significance.This paper introduces creep the method of combining the calculation of the coupling model with the numerical simulation is based on the theoretical basis of the predecessors,and the specific work is as follows:(1)Summarizing and expounding the failure characteristics,shape,and influencing factors of the slope,it is pointed out that in addition to human factors,the slope is mainly affected by rainfall and structural planes in the natural state.The analysis methods of slope stability are summarized and analyzed,and the differences between different analysis methods are compared.(2)The finite element software Plaxis is used to calculate the slope displacement and safety factor changes under different working conditions.The finite element software is used to establish the slope model,the model grid is divided and the debugging parameters are more consistent with the actual situation.Five different working conditions are established,and the influence of prestress loss on slopes of different grades,different rows of the same grade,and safety factor under different conditions is discussed,and compared with the measured data.(2)Taking a slope in Longnan,Gansu Province as a background,the finite element software Plaxis was used to calculate the slope displacement and safety factor changes under different working conditions.The finite element software was used to establish a slope model and five different working conditions were established.The influence of pre-stress loss on different levels of slopes,different rows of the same level,and safety factor under different conditions,and compared with the measured data,draws a conclusion that different rows of anchor rods and slopes of different levels have different effects on safety factor and displacement At the same time,the gray correlation analysis method is used to analyze the sensitivity of the slope safety factor to different influencing factors,and the influencing factors are arranged to obtain the most sensitive controllable and uncontrollable factors.(3)Taking the creep coupling model of rock and soil as the research starting point,considering the characteristics of large loss in long-term prestress prediction of the creep coupling model,more models are derived based on the(H-K)creep coupling model,so that the new model can predict the long-term The pre-stress level is closer to the real value.The composition and basic principles of the rock-soil rheological model are discussed,and the applicability of different creep coupling models to different soils is analyzed,and the creep parameters are back calculated from the monitoring data in the engineering examples.It was substituted into the written Matlab program for calculation and fitting.Based on the(H-K)model,the constitutive equation relaxation equations of the(H-3K),(H-4K)and(H-5K)creep coupled models were derived.And the creep equations were substituted into MATLAB software for fitting,and the stress loss law of the creep coupling model was obtained.It is concluded that the(H-3K)model can meet the needs of the project.