型钢混凝土柱粘结滑移本构关系与粘结滑移恢复力模型

Bond-slip constitutive relation and bond-slip resilience model of shape-steel reinforced concrete columns

进行了弯矩、轴力、剪力共同作用下型钢混凝土柱的粘结滑移性能试验。以试验所得的粘结应力-滑移关系曲线为基础,定义了三个特征粘结应力点,并提出了特征粘结强度、特征滑移的统计回归计算公式,建立了型钢混凝土柱距柱底50mm处的基准粘结滑移本构模型。以基准粘结滑移本构模型为基础,引入反应不同位置粘结应力和滑移分布差异的位置函数,建立了型钢混凝土柱任意位置的粘结滑移本构关系。综合考虑反复荷载作用下型钢混凝土柱粘结强度、滑移刚度退化规律,建立了型钢混凝土柱粘结滑移恢复力模型,提出了恢复力模型中骨架曲线、加卸载刚度的确定方式,加卸载路径、强度衰减规律以及滞回环规则。研究结果为型钢混凝土柱考虑粘结滑移的有限元分析和地震反应全过程分析提供了必要条件。

A series tests are conducted to study the bond-slip behavior of shape-steel reinforced concrete columns under bending, shear and axial forces. According to the experimental results of bond-slip curves at the point 50mm from the bottom of columns, three key bond strengths and the corresponding slippages are defined, and formulas for calculation of these key bond strengths and slippages are determined through regression. Using these key bond strengths and slippages, the basic bond-slip constitutive models are established. A position function reflecting the difference of bond stress and slippage in various places along the column is presented. Based on the basic bond-slip constitutive models and position function, a bond-slip constitutive equation applicable to all positions along the column is formulated. Considering bond degeneration in cyclic reversed loading, a bond-slip resilience model of shape-steel reinforced concrete column is proposed. Method is introduced to confirm the skeleton curve and loading rigidity as well as the strength attenuation and hysteretic rule of the bond-slip resilience model. The proposed bond-slip constitutive relation and bond-slip resilience model may be employed for finite element analysis and seismic reaction analysis of shape-steel reinforced concrete columns.