Study On Prestress Loss Evaluation Method Of Anchor Cable Based On Finite Element Method

There are a lot of slope engineering in our country,so it is very important to prevent and reduce the disaster.A kind of slope anchor technology is prestressed anchor cable frame structure.The main characteristics of prestressed anchor cable frame structure is able to make full use of the slope rock mass strength and bearing capacity,can greatly reduce the weight of structure,and ordinary masonry reinforcement technology has obvious advantages and economic benefits compared.Due to the influence of various external factors,the prestress of anchor cable will inevitably lose or even failure due to various external factors.Therefore,in the construction process of slope anchor cable prestress,the prestress of anchor cable should be tested.At present,the method of anti-pulling is the method to detect the prestress of anchor cabl.However,it is not perfect to evaluate the prestress loss of prestressed anchor cable through the value of the percentage value of prestress,which is used to detect the prestress under anchor.There are two main problems in the detection of prestressed anchor cable by the method of reverse tension.The first one is that it is not reasonable to use the same fixed percentage(20%)in different conditions.Second: at present,there is no scientific and effective theoretical basis for the 20% evaluation criteria.This paper through the ANSYS software modeling and analysis of different conditions,different degrees of influence of prestress loss by simulation of slope anchor cable under different working conditions on slope stability,to find the law from the results obtained in prestress detection,according to different conditions,should adopt different detection standards,this paper made the following work:(1)This paper introduces the structure,construction process and stress characteristics of prestressed anchor cable frame structure.(2)The failure types of the slope are analyzed,the factors that affect the stability of the slope and the main causes of the failure of the slope are found out.(3)he application of finite element theory,strength yield criterion and strength reduction method in slope stability analysis is analyzed.(4)By using the finite element method of ANSYS software to establish the four level model of three different slope gradient,the same simulation models of different level with the row anchor,the same model with a different row of anchor cable,the three models of the same row three conditions of prestress loss in the step by step under the condition that the variation of slope model the X and Y direction,the plastic strain development rule and the slope safety factor,and comparative analysis on the change law.(5)Conclusion: on the basis of the modeling process in prestress detection,according to the actual condition of finite element model is established for numerical simulation analysis,to determine a specific assessment of the standard conditions of prestressed anchor cable.(6)Some measures can be taken to reduce the prestress loss of slope anchor cable.