HRB500级钢筋混凝土框架柱的数值模拟与轴压比限值分析

Numerical simulation and axial compression ratio extreme analysis of HRB500 reinforced concrete frame columns

利用ANSYS对8个HRB500框架柱构件塑性铰区的抗剪性能进行了非线性有限元计算,模型中混凝土采用SOLID65单元,钢筋采用LINK8单元,分离式建模,破坏准则采用Willam—Warnke五参数破坏准则,混凝土本构关系采用多线性随动强化模型(KINH),钢筋的本构关系采用双线性随动强化模型(BKIN)。计算了模型的屈服位移、极限位移和位移延性系数,计算值与试验值符合较好,验证了计算模型的适用性;利用已校验的计算模型,变化HRB500框架柱构件的截面尺寸、轴压比与配箍特征值等参数,计算得出位移延性系数、轴压比与配箍特征值的关系表达式,进而给出HRB500框架柱在不同抗震等级下轴压比的建议设计限值。

Nonlinear finite element analysis of plastic hinge regions of 8 HRB500 RC frame columns under cyclic loading was calculated based on ANSYS. SOLID65 element was used for concrete and LINK8 element was used for reinforcement. Willam - Warnke five parameter＇ s failure criterion was used. KINH was used for concrete constitutive relation and BKIN was used for reinforcement constitutive relation. The yielding displacement, ultimate displacement and displacement ductility factor were all calculated. The calculation results and the experimental results is in good agreement, and the adaptability of finite element models is verified. Based on changed section sizes, axis compression ratios and stirrup characteristic values, the formula of relationship between displacement ductility factor, axial compression ratio and stirrup characteristic value is obtained for HRB500 RC frame column by verified model. Finally, the suggestion of limit values of axial compression ratio is proposed for different grades of seismic design.