UHTCC局部增强框架节点抗剪承载力计算方法

A calculation method for bearing capacity of ultra high toughness cementitious composite reinforced beam-column joints

通过8个超高韧性水泥基材料(UHTCC)增强框架节点的低周反复加载试验,得到了UHTCC增强框架节点的破坏形态、滞回曲线、骨架曲线和节点抗剪承载力,分析了节点核心区体积配箍率和轴压比对节点抗剪性能的影响,结合试验数据,提出了UHTCC增强框架节点抗剪承载力计算公式。结果表明,UHTCC能显著提高节点的抗剪承载能力,对节点核心区的箍筋有一定程度的替代作用;增大轴压比可提高UHTCC节点试件的初裂剪力;节点承载力公式计算值与试验值吻合较好,可为此类节点的试验和设计提供参考。

Through the experiments on eight Ultra High Toughness Cementitious Composite beam-column joints under reversed cyclic loading,the failure mechanism, hysteretic curve, skeleton curve and ultimate shear capacity of beam-column joints enhanced by UHTCC were obtained. The influences of volumetric ratio of stirrup at core area of joint and axial compression ratio on the shear bearing capacity of joints were analyzed. Combined with experimental data, a calculation method for bearing capacity of UHTCC reinforced beam-column joints was proposed. The results show that UHTCC can obviously improve the shear bearing capacity of beam-column joints and replace the stirrups at core area to some extent. Increasing the axial compression ratio can improve the initial cracking shear capacity of the UHTCC specimens. The calculation results agree well with the experimental results, and the proposed calculation method can be employed for future experiments and designs.