Mechanical Behavior Research On "Cable-Suspension" SystemTransformation Of Self-Anchored Suspension Bridge

Self-anchored suspension bridge has the advantages of beautiful appearance,novel structure,landscape and modeling,which has developed rapidly in recent years.Since the anchor suspension bridge of traditional construction method usually need to build support or temporary pier girder installation,terrain conditions have higher requirements for the construction site,which limits the development of the anchor suspension bridge,so urgently need a kind of both can satisfy the requirements of the stents or even no less,and can be convenient to realize the system transformation of construction technology.Cable-stayed buckle hang construction method is able to meet the requirements of the construction method,the construction method to set up the anchor of suspension Bridges need to pass "after the first suspension cable" system transformation process,structure has experienced a very complex stress process.At present,there is no mature experience in engineering field at home and abroad.This paper based on chongqing male goose rock rail service bridge engineering,in view of the "first after the suspension cable system structure in the process of transformation and law analysis,the main research contents and results are as follows:(1)The paper combined with traditional since anchor suspension bridge construction method,analysis of cable-stayed buckle hang a construction method of system transformation in the structure characteristic,proposed the "first after the suspension cable system control factors in the process of transformation and shall comply with the principle,puts forward some ideas of the system transformation process.(2)The paper combined with the structure characteristics of the engineering background,in order to control factors in the process of system transformation and shall comply with the principles for the design,put forward three system transformation construction scheme,and by using finite element software Midas/civil calculation and analysis of the three schemes,the "first after the suspension cable system transformation in the process of sling force and displacement of main cable and girder stress and the changing rule of the temporary suspension cable force.Compared with the traditional construction method,the stress of the main girder is different from the longitudinal distribution of the bridge and the variation of the stress on the lower edge of each section.Based on the evaluation criteria of construction period,construction economy and construction safety,the optimal scheme is obtained by comprehensive evaluation of various system transformation schemes.(3)On the basis of the system transformation project of the three,the "first after the suspension cable system transformation process of the main tower and temporary steel tower the whole process of deformation and stress distribution was analyzed,and studies the bridge tower change rule and the change mechanism of pushing stiffness.The local solid model of the main tower and temporary steel buckle is established and the local force of the connection part under typical construction condition is analyzed.(4)The space finite element model is established for the anchor suspension bridge construction stage and into a state of bridge were carried out the first and the second category of stability analysis,get the change of the stability safety coefficient in different stages of the process and the modal and buckling analysis shows that the structural buckling instability forms are primarily tower,and overall buckling stability coefficient in cable-stayed bridge phase should be greater than the buckling stability factor of system transformation stage.In addition,the influence of initial defect,wind load and temperature load on the stability of the system is also studied.