基于弹性扭转约束边界的高强度钢材波形腹板剪切屈曲性能研究

High strength steel has advantages of high yield strength and good processability. Fabricating corrugated steel webs in long span bridge with high strength steel effectively avoid use of ordinary thick steel web and then the reduction of mechanical property of ordinary thick steel web during cold working. The material property index and defect sensitivity of high strength steel are different from that of ordinary steel. In addition, the overall buckling stress calculation methods provided in existing codes were not considering elastic torsion restraint effect of flange on corrugated steel plates. In view of the above questions, this project focuses on the study of shear buckling performance of the corrugated high strength steel plates with edges elastically restrained against rotation. Based on the model test and numerical simulation, elastic torsion restraint effect of different flange connections on corrugated high strength steel plates and buckling performance influence factor of corrugated high strength will be studied. Shear buckling failure mechanism obtained from research can be used to guide corrugated high strength steel plates design with reasonable parameters. Computing theory of global shear buckling critical stress of corrugated steel plates will be developed, Research results provide theoretical basis for corrugated high strength steel plates design.

高强度钢材具有屈服强度高、加工性能好等优点，应用高强度钢材制作大跨径波形钢腹板组合梁桥的腹板可有效避免采用普通钢材厚板加工波形板时可能产生缺陷而降低腹板力学性能的弊端，但高强度钢材的材性指标以及对缺陷的敏感程度与普通钢材有别；同时，现行规范中的波形钢腹板整体剪切屈曲临界应力计算公式均未考虑混凝土翼缘板对腹板的弹性扭转约束效应。针对上述问题，本项目拟在考虑弹性扭转约束边界的基础上，对高强度钢材波形腹板的剪切屈曲性能展开研究。通过模型试验研究翼缘板与腹板间的不同连接方式对波形腹板的弹性扭转约束效应，采用数值模拟方法对影响高强度钢材波形腹板剪切屈曲性能的因素进行参数分析，得到高强度钢材波形腹板在弹性扭转约束边界下的剪切屈曲破坏机理与用于指导高强度钢材波形腹板设计的合理参数范围；建立考虑弹性扭转约束边界的波形钢腹板整体屈曲临界应力计算理论。研究成果可为高强度钢材波形腹板的设计理论依据。

高强度钢材具有屈服强度高、加工性能好等优点，应用高强度钢材制作大跨径波形钢腹板组合梁桥的腹板可有效避免采用普通钢材厚板加工波形板时可能产生缺陷而降低腹板力学性能的弊端。本项目对高强度钢材波形腹板的剪切屈曲性能进行了研究。首先，研究了波形钢腹板与翼缘板之间的真实边界，在此基础上，采用数值模拟方法分析了翼缘板尺寸、腹板高度、腹板厚度、波形直板段长度、波高、折叠角度等参数对波形钢腹板弹性剪切屈曲性能的影响；采用经试验验证的有限元模拟方法研究了高强度钢材波形腹板的弹塑性剪切屈曲性能，分析了整体尺寸、局部波形尺寸、初始几何缺陷和钢材强度等级对波形钢腹板弹塑性剪切屈曲性能的影响；最后，采用波形钢腹板剪切屈曲试验数据对现有计算方法的适用性进行分析，基于高强度钢材波形腹板的弹塑性剪切屈曲分析结果，给出了建议的的剪切屈曲强度计算方法。