大挑臂钢箱结合梁剪力滞效应研究

Research on Shear Lag Effect of Large-cantilever Steel Box Composite Beams

摘要:

宽桥面桥梁结构的剪力滞问题由来已久，目前针对钢箱结合梁的剪力滞效应的研究相对较少。该研究对某单索面大挑臂钢箱结合梁斜拉桥进行节段模型试验，通过有限元分析方法与实验结果相结合，系统探讨了不同工况下各板件的正应力分布特征。研究发现，在考虑剪力滞效应的影响下，全梁的应力控制点均位于根部，为优化设计提供了重要参考依据。同时，进一步揭示了剪力滞效应对正负弯矩作用下的应力分布特性的影响规律，为结构性能优化提供了重要的分析基础。

Abstract:

The shear lag problem of wide-deck bridge structures has existed for a long time. At present, there are relatively few studies on the shear lag effect of steel box composite beams. The segmental model test is carried out on a single-plane large-cantilever steel box composite beam cable-stayed bridge. By integrating the finite element analysis methods and the experimental results, the normal stress distribution characteristics of various plate components under different loading conditions are systematically discussed. It is found that the stress control points of the whole beam if considering the shear lag effect are all at the root section, providing the important reference basis for the design optimization. Furthermore, the influencing rule of shear lag effect on the stress distribution features under both positive and negative bending moments is further revealed, which provides the important analyzing foundation for the optimization of structural performances.