Study On The Safety Performance Of Earth-anchored Prestressed Concrete Single Slanted Pylon Cable-stayed Bridge

The earth-anchored prestressed concrete single slanted pylon cable-stayed bridge is a new type of combination system of cable-stayed bridge,which is developed gradually in recent years.The leaning tower of the cable-stayed bridge can balance a part of the weight of the main beam,which makes the stress of the structure more reasonable and achieves a better landscape effect.However,this type of bridge's stability is poor in the process of construction.It has a novel structural system and its stress state is complex.There are relatively few literatures about the safety performance of the bridge.Bridge workers need to understand the stress characteristics and safety performance of earth anchored single inclined tower cable-stayed bridge.So it is necessary to analyze the safety performance of the bridge.This paper takes an anchored prestressed concrete single tower cable-stayed bridge as the engineering background.On the basis of consulting a large number of relevant literatures,the cable-stayed bridge safety performance theory and analysis methods are summarized.The solid element model and beam element model of the cable-stayed bridge are established by using ANAYS finite element software,and the numerical simulation of the cable-stayed bridge is carried out.In this paper,the maximum cantilever stage and the bridge deck pavement stage are selected as typical construction stages.Considering the influence of nonlinearity,the stability and ultimate bearing capacity of typical construction stages are analyzed.This paper studies the stress characteristics of the cable-stayed bridge in the operation phase of the design load,and calculates the ultimate bearing capacity under different conditions.Considering the influence of the balanced load and the unbalanced load,the paper obtains the safety factor and the failure mode of cable-stayed bridge under different load conditions.The paper selects the cable fracture,the angle of the leaning tower,the span of the transverse beam and the structural system as the influence factor to analyse the influence of different parameters on ultimate bearing capacity of cable stayed bridge.The results show that the stability safety factor of cable-stayed bridge in construction stage is large,and its safety performance is good.Under the design load,the stress state of the bridge is reasonable in the operation stage.Considering the different loading modes of automobile load,the bridge has a large safety factor when it reaches the ultimate bearing capacity,and the cable-stayed bridge has a larger safety reserve.When the inclined cable of the back tower is broken,its influence on the ultimate bearing capacity of the cable-stayed bridge is greater than that the main span side cable is broken.On the basis of the angle of the original tower,the ultimate bearing capacity of the cable-stayed bridge decreases with the decrease of the angle of the leaning tower,and increases first and then decreases with the increase of the inclination of the leaning tower.The span between transverse beams plays an important role in the ultimate load carrying capacity of cable-stayed bridges when the bridge bears the unbalanced load.The rigid frame system should be preferred for earth-anchored prestressed concrete single slanted pylon cable-stayed bridges.