Steel Truss Arch Bridge Research On Key Technology

China's steel truss arch bridge development is lagging behind,as well as the need for construction steel truss arch bridge,and some of the advantages and features,combined with its attractive appearance,construction speed,low cost,with a strong competitive edge,domestic steel truss arch bridge grows demand and steel truss arch bridges' research also increases.In this paper,Nanqin railway three shore yongjiang river bridge as the engineering background,the construction process of bridge is discussed,including the overall construction plan,large temporary facilities,side span and across different erection of steel beam and the closure segments in the closure,etc.There are many types of steel truss arch bridge construction method,and the bridge adopts the erection of suspension process,need to put in more temporary facilities,many factors affecting the safety of bridge construction and increase the risk of the construction difficulty and closure.Steel truss is set to cross,in order to enable the resistive overturning safety factor meet the requirements,should be carried out the heavy pressure on both sides,for environmental protection and cost saving consideration,this paper boldly adopted the repeated use of piers based as loading material of expanding method,this method has a certain innovation.In the process of midspan erect,bar stress and vertical displacement are larger,this article adopts the method of installation tower and hang stay-cables adjustment,which reduces the construction difficulty and risk,to ensure the bridge closed successfully.Paper uses the finite element modeling software MIDAS/CIVIL,the construction process is simulated and analyzed beam erection during rod stress,buttress reaction force,vertical displacement of the cantilever end and a longitudinal displacement,the results show that these parameters are in line with regulatory requirements,indicating the construction method used in this paper is feasible in theory,can be used as a reference steel truss arch bridge.To avoid overturning the tower and to ensure construction safety,paper finally checks its stiffness,strength and stability before sling tower put to use;Monitor the construction process of the bridge,providing beam elevation and hanging cable tension measured data by comparing analysis and constant correction,bridge construction to ensure accuracy.