钢-混凝土组合简支桥面连续结构横向应力分析

针对钢-混组合简支梁桥的桥面连续结构开裂等病害,围绕桥面连接板的横桥向应力问题,采用线弹性理论和板的偏微分方程进行分析,得出了桥面连接板挠度和应力的分布函数,建立非线性有限元模型,并进行实桥荷载试验.通过比较理论解、有限元解和实测试验结果,证实了理论解和有限元的有效性.根据得到的分布函数,发现横桥向和纵桥向上的最大拉应力出现在钢梁端部位置的连接板的上缘.此外,还分析了连接板区域尺寸变化对横桥向应力峰值的影响,包括纵梁端部距支座的长度、纵梁的间距以及连接板区域整体尺寸变化.结果表明：较小的纵梁间距和较长的纵梁端部与支撑之间的距离会导致连接板中的横向拉应力峰值增加,并提高横向拉应力在总应力中的占比,从而导致桥面连接板早于设计荷载开裂.因此对于纵梁间距较小、梁端长度较长的钢-混组合简支梁桥桥面连续结构,仅计算其纵桥向受力性能会导致计算结果偏危险,建议按照本文方法考虑横桥向应力对桥面连接板的影响.

Transverse Stress Analysis of Link Slabs in Simply-supported Steel-concrete Composite Beam Bridges

This study examines the transverse bridge stresses of the link slab for the disaster such as the structural crack in the simply-supported steel-concrete composite bridge. The link slab''s deflection and stress distribution functions are determined using linear elastic theory and the partial differential equation of the plate. A nonlinear finite element model is also established based on actual bridge load testing. The theoretical solution, finite element solution, and real bridge load test results are compared to validate the theoretical solution and finite element. The study shows that the upper face of the link slab at the end of the steel girder experiences the maximum tensile stress in the direction of the transverse and longitudinal bridge. The paper also explores the impact of the link slab area size on the peak stress in the transversal bridge direction. Results reveal that smaller longitudinal beam spacing and longer longitudinal beam end length increase the maximum transversal tensile stress of the link slab, causing the link slab to develop cracks before reaching the design load. Therefore, for a jointless bridge with a small longitudinal girder spacing and a long girder end length, only calculating the mechanical performance in the longitudinal bridge direction yields dangerous calculation results. It is advisable to consider the transverse bridge direction stress according to the method in this paper.