钢筋混凝土异形柱轴压比限值研究

根据《混凝土结构设计规范》关于正截面承载力计算原理，对L形、T形和十字形截面柱的轴压比限值进行了数值计算分析，得出了不同截面形状、不同纵向配筋率和不同和轴角度时的轴压比限值随含箍特征值的变化规律。提出对于T形柱和L形柱，目前按规范规定的轴压比限值或广东省标准规定的轴压比限值进行异形柱抗震设计，是偏于不安全的；按天津市标准进行异形柱抗震设计，其可靠度需进一步研究。十字形截面柱配筋基本均匀布置，平衡破坏时轴压比较矩形截面情形略有提高，采用规范规定的矩形柱轴压比限值是可行的，并且柱的延性比矩形柱的有所提高。

Study of ultimate axial compression ratio for specially-shaped columns

The ultimate axial compression ratio for the specially shaped columns is computed by the numerical method. The effects of the section shape, the angle of neutral axis and the content of steel on this ultimate axial compression ratio are analyzed and the design requirements for each form are also discussed. The following conclusions can be drawn: For T ,L shaped columns, it is not safe to design according to the ultimate axial compression ratio of the present Design Code For Concrete Structures and the criterion of Guangdong Province, and the reliability of the criterion of Tianjin City needs to be studied. For Cross shaped columns, it is feasible to design according to the ultimate axial compression ratio of the present Design Code For Concrete Structures.