基于静动载试验的钢-UHPC组合桥面应用研究

Study of Application of Steel-UHPC Composite Deck Based on Static and Dynamic Load Tests

为评估钢-超高性能混凝土(UHPC)组合桥面体系(通过剪力钉将配筋UHPC薄层与正交异性钢桥面板组合而成的新型桥面结构)的实桥应用效果,以太原摄乐大桥为背景,分别建立80 mm厚SMA铺装层、60 mm厚UHPC+80 mm厚SMA铺装层2种铺装方案有限元模型进行静力性能分析,并对桥面行车道开展静、动载试验研究。结果表明:设置UHPC铺装层能显著提高结构刚度,大幅降低正交异性钢桥面板各构造细节应力;实桥静载测试数据与计算值吻合度较高;当车辆以60 km/h设计速度行驶时,钢-UHPC组合桥面无明显动力冲击效应;钢-UHPC组合桥面体系在实桥上应用效果良好。

In this paper,the Shele Bridge in Taiyuan is used as a case to evaluate the application effect of steel and ultra high performance concrete(UHPC)composite deck system on real bridges.The steel-UHPC composite deck system refers to the deck structure where the thin reinforced UHPC slabs are connected with the orthotropic steel panels via shear studs.Finite element models of two types of pavements were established for static performance analysis,including the pure 80 mm-thick SMA pavement and the combined 60 mm-thick UHPC and 80 mm-thick SMA pavement.Static and dynamic load tests were also conducted for the traffic lanes that have already experienced a winter and heavy load operation.As per the study,adding UHPC pavement can significantly improve the stiffness of the structure,remarkably reduce the stresses in each structural details of the the orthotropic steel deck.The stress level in the steel-UHPC composite deck system after a winter and heavy load operation is low.The measured data agree well with the calculations,proving that winter time and heavy loads have negligible effect on the stiffness and load bearing performance of the composite deck.When the vehicle was passing through the bridge at a speed of 60 km/h,no obvious impact effect was observed on the steel-UHPC composite deck,indicating that the application effect of the steel-UHPC composite deck system on the real bridge is good.