Construction Control Research Of The Hoisting Steel Trussed Girder Of Suspension Bridge

The modern suspension bridge consisting of stiff girder and main cable is a system of flexible suspension. It becomes the first choice of long-span bridges for its great spanning capacity and lightness structure model. To ensure suspension bridges'safety during construction and service, the research on several problems of the hoisting steel trussed girder of construction controlling of the long-span suspension bridge is developed in this paper based on Sidu River Suspension Bridge in the west of national highway from Shanghai to Chengdu. The main contents and achievements are as following:1. Aiming at the process the hoisting steel trussed girder of construction controlling of Sidu River Suspension Bridg, the encountered problems of pushing cable saddle in actual, the control scheme of the state being under the control of the cable saddle freely moving is put forth. And the new controlling project is intensively studied.2. The main impact factors of the cable sadde freely moving are studied. The relationship of actual measuremen values of dissymmetry of tower and the monitoring deviator of cable saddle with the values theoretical arithmetic is analyzed. The analyzing thought of calculation comparison about the sustainable of development programs'cumulant of cable saddle moving is obtained, and the analyzing thought is adopted to decide the sustainable of the changing of deviator of cable saddle.3.In the whole construction controlling of the hoisting steel trussed girder, monitoring deviator of cable saddle, dissymmetry of tower, stress of tower, the configuration changing of main cable and steel truss girder,as well as the strain of anchorage cable and so on. The results drawn from the model comparison with the measured value show that the precision demand of the configuration changing of main cable and steel truss girder is met,and the control effect is ideal.4. Aiming at construction features of the steel truss girder suspension bridg, the change law of configuration changing of the hoisting steel trussed girder of construction is studied. The construction scheme of secondary dead load and the suitable time of rigid connection are obtained after the closure of the hoisting steel trussed girder, and the corresponding suggestion is put forward.5. The adjustment technics and effect of the strain of anchorage cable of Sidu River Suspension Bridge are illustrated in this paper, and the change of the strain of anchorage cable is analyzed in the end of the hoisting steel trussed girder of construction. From the effect of adjustment and monitoring, the stress of the upstream and downstream cable is harmonious, and the control effect was favorable.