沌口长江大桥钢桥面铺装荷载谱研究

Study on Load Spectrum of Steel Deck Pavement in Zhuankou Yangtze River Bridge

为更有效预测正交异性钢桥面铺装层的疲劳寿命,需针对项目预测交通量尤其是重载情况进行分析研究,对正交异性钢桥面板的结构特性进行力学分析。通过调研分析临近过江通道实际监测的交通数据,得出桥面轴载谱。建立钢桥面铺装有限元模型进行计算分析,得出钢桥面铺装最不利荷位中心横向位于U形肋与桥面接缝处,纵向位于距离横隔板0.2 m处,得到了不同轴载作用下铺装层的关键力学指标形变量和应变量,结合轴载谱得出荷载谱,并推算出初步设计阶段铺装层的疲劳寿命仅为2年。

In order to predict the fatigue life of pavement layer in the orthotropic steel bridge more accurately,the predicted traffic volume in a project was investigated,especially the traffic volume of heavy loads,and the mechanical analysis on the structural characteristics of orthotropic steel decks was conducted. The axle load spectrum that could be applied to the bridges was determined by analyzing the real-time traffic data of a crossriver passageway. A finite model for the steel bridge pavement was developed and then employed to calculate the worst loading position. It is concluded that the center was horizontally located at the joint between U shaped stiffening rib and bridge pavement and was longitudinally away from the diaphragm plate with a distance of 0.2 m. The key mechanical indices of pavement layers under different loading conditions（ i. e. deformation and strain） were then obtained,which,along with the axel load spectrum,and were utilized to compute the load spectrum.And it is estimated that the fatigue life of pavement in the preliminary design stage is only 2 years.