Research On Construction Control Of Long Span Steel Box Girder Bridge

In recent years,with the national policy guidance to increase the proportion of steel structure bridges,the design institute needs to compare and select the steel structure bridge schemes from the initial stage.With the gradual increase of traffic volume,the continuous improvement of bridge load level and the navigation level under the river crossing bridge,there are more and more new steel box girder reconstruction and expansion projects.Based on the actual project of Xinzhan bridge and longxigang bridge across Xitiaoxi River of Hangzhou Nanjing Expressway,this paper studies the construction control of reconstruction and expansion of steel box girder bridge without deck pavement.For the construction control method of steel box girder bridge with sectional transportation,on-site hoisting,positioning and assembly,it mainly analyzes and calculates the required parameters and safety stability in the construction stage according to the actual site conditions,design parameters,specifications and standards,construction scheme and other factors,supplemented by the finite element theoretical analysis software.1.Firstly,according to the actual conditions of the site,design parameters,specifications and standards,construction plans and other factors,the overall construction process is theoretically simulated,and the theoretical construction process is established to provide parameter reference and comparison for the next stage of construction.2.Through the actual measurement of the internal temperature transfer effect of the steel box girder,the temperature gradient transfer effect formula is fitted,and the temperature gradient effect of the steel box girder without bridge deck pavement is simulated by ANSYS,and the measured temperature gradient effect is mutually verified,and the steel box is obtained The optimal time period for beams to be welded together provides a reference for the analysis of the influence of the temperature field during the construction of steel box girder without bridge deck pavement in some areas.3.Carry out numerical theoretical analysis on the bridge surface elevation,introduce the error trend chart in the linear control to adjust the bridge surface alignment,and use the data set difference analysis for the error,confirming that the artificial error adjustment can promote the bridge alignment and design alignment More consistent.4.Carry out solid element simulation in the construction stage that produces large stress and deformation,and load according to the actual situation on the spot to determine whether the structure is safe and stable.5.Comparing the reinforcement methods for the transverse partitions with insufficient local strength,establishing the physical model of the reinforcement scheme,and adjusting the position of the reinforcement corbels to compare the effect of the corbel position on the bearing capacity of the transverse partitions The size,the law of the reinforcement effect of the corbel position on the diaphragm is summarized,and the maximum effect plan is adopted to reinforce the diaphragm,and the actual strain data is collected.The results show that the compressed diaphragm at the front fulcrum after reinforcement can meet the bearing capacity requirements.