Study On Basic Mechanical Properties Of A New Type Of Cable-stayed Arch Bridge

Cable-stayed arch bridge is a new bridge and it combines the advantages of bridge and arch bridge.Cables can provide multiple supports for the arch and the arch also increases the stiffness and stability of the bridge and the two factors complement each other.The research on the new system of cable-stayed arch bridge is relatively few and most of the studies focus on the analysis of the static and dynamic performance of existing bridges.Based on the cable-stayed arch bridge,this paper introduces two kinds of new structures;arch string cable-stayed arch bridge and cable-stayed arch bridge with truncated cables and the basic mechanical properties such as cable force,bending moment and deflection of the middle of the span are studied.In this paper,the parameters of the two systems are analyzed by using Midas civil,and the reasonable range of parameters is summarized.The main research contents and results are as follows:1)Based on the previous research,this paper describes the basic structural layout of the arch string cable-stayed arch bridge and cable-stayed arch bridge with truncated cables and analyzes the two vertical and horizontal layout and construction,anchorage and other details,and uses Midas civil to analyze.As an extension of beam string structures,arch string cable-stayed arch bridge can give full play to the synergistic effect of cable,suspender and arch when the clearance does not meet the requirements.Cable-stayed arch bridge with truncated cables is based on the traditional cable-stayed arch bridge and cables on arch ring cut,and keep in the same line and the two structural systems can provide more effective support for the main girder,and the cables in both systems can provide more support to the arch.2)Control variable method is used to analyze the mechanical properties of string arch cable-stayed arch bridge,and the models with five groups of cables and four span is made by midas civil and compared with the traditional cable-stayed arch bridge,the string arch system has its advantage in static performance,and through the parameters of height span ratio,arch span ratio,height rise ratio,eccentric ratio,a suitable range of parameters string arch is put forward and the layout of the expansion joints is analyzed.The influence of different parameters on the cable-stayed arch bridge is also compared and it can provide reference for practical engineering.3)The basic mechanical properties of the cable-stayed arch bridge with truncated cables are studied using the control variable method,and compared with the traditional cable-stayed arch bridge,the new system shows its advantage and parameters such as the length of the anchorage area of the cable on the arch,height-span ratio,arch rise-span ratio,are analyzed and the suitable range of the cable-stayed arch bridge with truncated cables is showed.In the end,the comparable analysis of the string arch and the truncated cable systems is made and the suitable ranges of the two systems are showed and it can provide reference for practical engineering.