基于拓扑优化及拉压杆模型的宽箱横梁配筋方法研究

Study on Reinforcement Calculation of Wide-box Cross Girder Based on Topology Optimization and Strut-tie Model

以一座大悬臂箱梁桥全桥实体分析为基础,得出横梁在多种荷载工况下的受力特点,进而得出横梁受力的简化荷载模型,以实体分析的结果能很容易确定提出的荷载简化计算模型的各参数值。确定荷载模型后,以二维平面应力单元模拟横梁对其在最不利荷载工况下进行拓扑优化,得到横梁用于拉压杆模型的构型,并总结了类似形式横梁拉压杆模型的构造方法,最后结合规范给出了针对各拉、压杆件的配筋计算公式。

Based on the entity analysis of some box girder bridge with cantilever, the stress characteristics of the cross girder under various load cases are obtained, and then the simplified load model of the cross girder is derived. According to the finite element analysis result, the parameters of the proposed model can be easily determined. After these, the topology optimization of the cross girder based on a stress model with 2D plan is implemented under the most unfavorable load case, and the configuration of the strut-tie model is obtained. Based on the topology optimization result, the method for establishing the strut-tie model is summarized. Finally, the reinforcement calculation formulas for the struts and ties are given according to the corresponding standards.