钢-UHPC组合梁横向接缝构造形式及抗弯性能研究

Study on Transverse Joint Structure and Flexural Performance of Steel-UHPC Composite Beams

提出一种钢-UHPC组合梁横向接缝构造形式,并对横向接缝进行负弯矩试验和全过程受力理论分析。结果表明:负弯矩作用下,UHPC表面裂缝呈多缝密集发展,接缝界面位置为试件薄弱区;提出的最大裂缝宽度计算公式可准确预测界面裂缝发展,考虑UHPC面板受拉刚化效应的挠度计算方法和弯矩简化计算方法可以较好地吻合横向接缝弯曲受力状态全过程。文中接缝构造和弯曲理论分析可为组合梁设计和计算提供一定参考。

A structural form of transverse joints of steel-UHPC composite beams was proposed, and the negative moment test and theoretical analysis of the whole process of transverse joints were carried out.The results show that, under the action of negative bending moment, the cracks of UHPC develop intensively and the joint interface is the weak area of specimen.The proposed maximum crack width calculation formula can accurately predict the development of interface cracks, and the proposed deflection calculation method and simplified bending moment calculation method considering the rigidization effect of UHPC panel under tension can well match the whole process of bending stress state of transverse joints.The analysis of joint structure and bending theory can provide some reference for the design and calculation of composite beams.