简支空心板桥车辆荷载效应分析

Research on Different Standard Vehicle Load Effect of Simply Supported Hollow Slab Bridges

车辆荷载模式随着中国桥梁相关规范的更新进行了调整,以空心板桥为研究对象,利用Midas/Civil建模分析。分别针对《城市桥梁设计准则》(CJJ1l-93)、《城市桥梁设计荷载标准》(CJJ77-98)和《城市桥梁设计规范》(CJJ11-2011)3种不同时期发布的规范要求的标准车辆荷载进行加载,计算并分析新旧规范下的荷载组合效应差异,以及挠度和冲击系数之间的差别。研究结果表明,对于简支空心板桥,必须加强支座处抗剪验算;同时,在3种不同时期城市桥梁设计规范的标准车辆荷载(不计冲击力)作用下产生的挠度效应均能满足各自规范要求。

The vehicle load patterns have changed along with the updating of Chinese bridge design codes. To investigate the different load effect combinations,deflections,and impact coefficients under old and new Chinese codes,simply supported hollow slab bridges were analyzed based on real engineering projects. The FEM software MIDAS / Civil was adopted to establish the numerical model. Different vehicle load patterns defined in 3 versions of Chinese bridge design codes,which are Code for Design of the Municipal Bridge（ CJJ 11-93）,The Standard of Loadings for the Municipal Bridge Design（ CJJ 77-98）,and Code for Design of the Municipal Bridge（ CJJ 11-93）,were used in the analyzing process. The difference of load effect combinations,deflections,and impact coefficients under the 3 versions were studied. The research result indicates that the shearing resistances of bridge bearings are essential for simply supported hollow slab bridges. The deflection effects of the different vehicle load patterns can respectively meet the requirements of the 3 codes.