钢筋钢纤维高强混凝土梁柱节点承载力计算方法

Calculation method for bearing capacity of steel fiber reinforced high-strength concrete beam-column joints

通过7个钢筋钢纤维高强混凝土梁柱节点和1个钢筋高强混凝土梁柱节点的低周反复加载试验,研究钢筋钢纤维高强混凝土梁柱节点的受力机理及破坏模式,分析钢纤维体积率、节点核心区配箍率以及柱端轴压比对节点受剪承载力的影响。结果表明:钢筋钢纤维高强混凝土梁柱节点的破坏主要有节点核心区剪切破坏和梁端弯曲破坏两种模式;随着钢纤维体积率和节点核心区配箍率的增加,节点受剪承载力显著提高。结合对国内外相关试验数据的综合分析,分别提出了考虑轴压比、钢纤维体积率以及节点核心区配箍率影响的适用于钢筋钢纤维普通和高强混凝土梁柱节点受剪承载力计算方法,以及考虑钢纤维影响的节点梁端受弯承载力计算方法。

Through the experiments on seven steel fiber reinforced high-strength concrete （SFHSC） beam-column joints and one high-strength concrete beam-column joint under reversed cyclic loading, the mechanical characteristic and failure mode of SFHSC beam-column joints were analyzed; the influencing factors, such as the steel fiber volumetric ratio, stirrup ratio and axial compression ratio on shear capacity of the joint core region were studied. The results show that the fundamental failure modes of SFHSC beam-column joints are shear failure in the joint core region and flexural failure in the beam end; the shear capacity is improved evidently with the increase of the steel fiber volumetric ratio and stirrup ratio. Finally, the calculation method for shear capacity of joint core region which not only considers the affecting factors mentioned above, but can also be applied to conventional steel fiber concrete beam- column joints and SFHSC beam-column joints was developed; and the calculation method for flexural capacity of beam which considers the influence of steel fiber was proposed