高强箍筋约束高强混凝土轴心受压本构关系研究

约束混凝土是克服高强混凝土脆性的重要措施，采用高强箍筋约束能够有效的改善受压构件的力学性能。同时，约束混凝土的本构关系是结构非线性分析的基础，本构关系的选取对计算结果的合理性有显著影响。该文基于多组高强箍筋约束高强混凝土轴压试验数据，提出了改进的约束混凝土本构模型，分析了高强箍筋应力的发挥水平，给出了约束混凝土峰值应力、峰值应变和极限应变的计算公式。计算结果表明建议的本构模型与试验曲线符合较好。该模型可用于高强箍筋约束混凝土构件的非线性分析。

UNIAXIAL COMPRESSIVE STRESS-STRAIN MODEL FOR HIGH-STRENGTH CONCRETE CONFINED WITH HIGH-STRENGTH LATERAL TIES

Lateral ties in the concrete component play an important role in overcoming the fragility of high-strength concrete. High-strength lateral ties can improve the mechanical behavior of compressed members effectively. Meanwhile, as a basis requirement in the nonlinear analysis of a structure, the stress-strain model has a remarkable influence on the validity of computed results. Based on a series of experimental results of concrete specimens confined with high-strength lateral ties subjected to axial loading, a modified confined concrete model is developed. The stress of high- strength lateral ties is analyzed, the formulas to determined peak stress, peak strain and ultimate strain are proposed. The results show a good agreement with experimental curves. The model is feasible in the nonlinear analysis of the confined concrete member confined with high-strength lateral ties.