连续箱梁桥车辆荷载效应研究

Research on Different Standard Vehicle Load Effect of Continuous Box Girder Bridge

车辆荷载模式随着中国桥梁相关规范的更新亦有相应调整,为了解现存连续箱梁桥在新的车辆荷载模式下的结构响应,分别选用《城市桥梁设计准则》(CJJ1l-93)、《城市桥梁设计荷载标准》(CJJ77-98)、《城市桥梁设计规范》(CJJ11-2011)3种不同版本规范中的标准车辆荷载。选取一座旧桥利用Midas/Civil建模分析。研究结果表明,对于连续箱梁桥,必须加强各跨跨中抗弯和中墩墩顶处的抗剪验算;同时,该桥的初始设计汽-超20级荷载不能满足"11"规范城-A级车道荷载边跨跨中最大弯矩的验算要求。

The vehicle load patterns have changed along with the updating of Chinese bridge design codes .To investigate the structural responses under the new Chinese code ,an existing continuous box girder bridge was analyzed based on a real engineering project .Different vehicle load patterns defined in 3 versions of Chinese bridge design codes were used in the analysis process ,which were CJJ11 - 93 ,CJJ77 - 98 ,and CJJ11 - 2011 .The FEM software MIDAS/Civil was adopted to establish the numerical model .The research result indicates that the bending resistance of mid-span and shear-ing resistance of center piers’ top are essential for continuous box girder bridges .The bending resistance under the initial vehicle load design of HS 20 cannot meet the requirements of maximum bending moment for urban class A roads defined in CJJ - 2011 .