Key Technology Research Of Long-span Steel Truss Cable-stayed Bridge Construction Control

In recent years, with the board and cable-stayed truss bridge development, a new form ofbridge-plate girder cable-stayed bridge came into being. It inherits the advantages of acommon plate truss bridge with cable-stayed bridge, has a better application of performance,especially in terms of long-span bridges, has a high competitive value, which is the importantreason of quick development of long-span cable-stayed bridge truss plate at home and abroad.To ensure this long-span bridge construction safety, construction monitoring is an essentialpart. Basing on the construction of rail-cum-Tongling Yangtze River Bridge, this paper hasbeen studied for key technologies of the construction monitoring, especially in cable forcecontrol, the main contents are as follows:(1) Molding and contrasting of FEA molds. Relying on the background of TonglingYangtze River Bridge and basing on wide absorption of the results of previous studies, thepaper further explores the key issues in molding of long-span truss plate cable-stayed bridge,including the simulation of the floor system、bridge tower、cable and boundary conditions.（2）Contrasting the theoretical data of different FEA. The paper molds the Tonglingbridge with FEA Midas2011and TDV2008.Contrasting the theoretical data of above twomodels with data of3Dbridge provided by China Railway Bridge Bureau of Investigation andDesign institute, the paper concludes that TDV and3Dbridge has more accuracy than Midasin the result of FEA.(3) Technology of steel strand cable force uniformity control. Based on the principle ofequivalent tensioning method, the paper derives the program of Tongling bridge in strandcable tension uniformity control and achieves the goal of uniformity control of the cablestrand, proves the practicality and reliability of intelligent tensioning systems;(4) Technology of steel strand cable force control. Basing on the contrast and analysis ofthe advantages and disadvantages of various testing methods employed in Tongling bridgeand via the measured data and accurate calculation analysis, the paper draws the conclusionthat the vibration frequency method has a large advantage in bridge cable force testing.