闵浦大桥上层钢桥面铺装力学分析与优化设计

Mechanistic Analysis & Optimizing Design of Upper Layer-Steel Bridge Deck Paving of Minpu bridge

以沥青混合料铺装层的最大拉应力、铺装层与钢桥面板间最大剪应力等为控制指标,对闵浦大桥双层桥面的上层钢桥面裸板及铺装层进行了力学响应分析。计算结果表明:轮载作用下正交异性钢桥面板的力学响应具有显著的局部特征,与荷载作用位置密切相关;上层钢桥面上弦杆宽度范围内局部的变形量接近0.8mm,对铺装层的受力不利,应进行加劲处理;上层钢桥面上弦杆靠近轮迹带的支撑点和T型纵向加劲肋与钢表面板的交汇点为钢桥面铺装受力最不利点,应进行优化设计。最后提出:对上弦杆部分的钢桥面板进行局部加劲处理,供载重骑车行驶的外侧两车道的钢桥面板厚度宜采用16mm。

Taking the largest tensile stress in asphalt concrete layer and the largest shear stress between steel deck and asphalt concrete layer as the control indicators, the mechanical response of the upper layer naked steel bridge and asphalt concrete layer of Minpu Bridge is analyzed. The results show that: under the wheel load, the mechanical response of orthotropic steel bridge has significant local features, and is closely related to the location of loads; the deformation of the part within the width of upper chord is about 0.8 mm, which is disadvantage to the paving and should be further stiffened. The support points around the tracks of the upper chord of steel deck and the joint of T-vertical stiffening rib and steel deck are very sensitive to the loading, and should be optimized. It is suggested that the steel deck near the upper chord should be locally stiffened and the thickness of the outside steel deck with heavy loads had better be increased to 16 mm.