A Study Of Pushing Construction Of Wide Box Beam Of Large Tonnage

A curding to the top-pushing of R^7# box bvidge in wu su of shan xi province and the study of the newest top-pushing construction, the model of the strueture is established. Then a loud test on the bridge is done.by selelting proper parameters and rectifiny the design.The internal force of the stnllture is analysed acurding to the construltion stadge and exercise stadye by analyzing the construlture. System of bridge. Then the force capability is analysecl through the angle of bending of protruit freeness torsion and restrilting torsion. On the section of box beam, the force of bending will induce, the asymmetry of positive stress. When it transfers from venter bourd to the top bourd. The shearing force lag effctions is analysed and the prestress system of wide box beam which is constructed by the metholl of top-puching is designed. The prestressecl steel rope is disposed in the top bourd and bottom boord of box beam by adopting the principle of "center disposing", therefore, the pressure stress on the secton will be uniformity to suit for the positive and negative bending moment of top-pushing beam and clecreuas the second force because of prestress.To fuvther dearly understand the working pevfor mance of wide box-beam bridge, it adopts super SAP91 lineav electvostatic force pvocedure to analyse and calculate fovce capability, which is made up of by different work condiction in the worst construction condition and the stage of exercise about box-beam bridge. The results manifested that tha coustuction model is cvedibile and the amalise concequence is pvecise. Through constracting and analyzing the single peak-push and severals points peak-push, it adopts the single peak-push method to make construction, that is exerting a big tonnage peak-push force in a section. It also andlyses the horizoutal and vevticular stability of the rigid peak pole and the result indicates the stability meets demamd, which is the horizontal and verticualav position of the rigid peak-pole systerm.To design the top-pushing force, it fanally certains the imposed horizontal equipment used to construct, and designs the pnemaking flat foof.In the course of the construction, it also can analyse the reasons of deviation and rectify them.The artide reserches the premaking of box-beam bridge, the top-pushing craftwork, joint construction and method among of the concveate bridge, the joint method between the box-beam bridge and the lead-birder, it also introduces the construction of the temporary frusta and the adjustmeat of the temporary frusta in the course of construction.It chovses dynamic and static experiment project. Experiment result shows bridge box beam has well whole nature; and shows box beam stiffness completely satisfies designed desire. Autual survey value of charactersistic section processed by worst load is less tham academic calculate value, draw-bend work performance of main suffer-power section is completely reliable; resisted woring work of bridge body is well- balanced, performance of horizontal spreading load is all right.Concussion coefficient value is all less than 1.10125 adhitited in construction calculate, and concussion coefficient brought by auto of same load and different rate has no distinct difference, it shows bridge beam and bridge floor satisfies useness desive.Top-pushing construction method is one of advanced and big outlook contruction methods in the present age, which has capacious.