Anti-overturning Stability Research Of Curved Beam Bridge With Single Column Pier Under Overloaded Customized Transport Vehicle Load

Highway customized transport plays an important role in the infrastructure construction of China.Emergency situations might occur on the bridge during the passing of a customized transport vehicles(CTV)and result in partial closure of the traffic lane,thus CTVs must drive deviating from the center line of bridges,which has a negative impact on the transverse anti-overturning stability of curved beam bridges with single column pier.In recent years,bridge collapse accidents have occurred frequently in China.According to the statistical investigation,curved beam bridges with single column pier account for a high proportion.In allusion to the problems of eccentric running of CTVs due to emergency and overturning of curved beam bridges with single column pier,this paper takes curved beam bridges with single column pier as research object and mainly conducts the following research work:(1)In order to establish CTV and curved beam bridge coupled vibration analysis system,this paper elaborates the formation of space coordinate transformation matrix.Besides the existing literature of selecting five kinds of typical CTV models of dynamic analysis lay the foundation of the system establishment.The subsequent calculation and analysis are carried out based on the analysis system.Finally an application example is given to validate the calculation precision of analytic system.(2)The coefficient of anti-overturning stability of curved beam bridges with single column pier is calculated based on the latest specification.Then mainly analyze the influence of the four main structural factors on the inhomogeneity of reaction force of double supports at the end of the beam and torsional moment inside and outside of the beam,which affect transverse anti-overturning stability of curved girder bridges with single column pier,including the radius of curvature,the eccentricity of the block in the single bearing,the distance of double pedestal piers of side piers,torsional span.And get the influence rule of four main factors on the anti-overturning stability of curved beam bridge with single column pier.In addition,the influence of lateral eccentricity of CTV on the anti-overturning stability of bridge is analyzed,and the critical eccentricity of CTV and the overturning area of bridge are determined.(3)The sample bridges are selected to calculate the destabilization effect of bridges under five types of typical CTVs and highway-I grade lane loading respectively,and conduct the analysis of specific value.Thus the anti-overturning safety coefficient determined of curved beam bridges is 5.4 and the most unfavorable vehicle model for bridge stability is C-IV CTV on condition that connected length of the bridge is less than 120 meters.The anti-overturning stability of the bridges under CTVs load can be transformed into the anti-overturning stability of the bridge under the highway-I grade lane loading.The result shows it is not easy to satisfy the requirement that the unidirectional compression supports of curved beam bridge with single column pier are always compressed under CTVs load.(4)Constitutive model of rubber bearing is determined and fine models of box girder and bearing are built to simulate the anti-overturning stability.Finally compare the results of simulation analysis with those calculated by anti-overturning stability analysis method in the latest specification,which shows the simulation results based on the fine model are more accurate and reasonable.It is suggested that analyzing the anti-overturning stability of the curved beam bridges with single column pier under CTVs by using fine model.