RC框架-内填带竖缝剪力墙结构的滞回性能及计算模型研究

Cyclic behavior and analytical model of RC frame with infill slit shear walls

为研究钢筋混凝土框架-内填带竖缝剪力墙(RCFW)结构的抗震性能,对两个单跨两层、缩尺比为1∶2的RCFW试件进行了拟静力试验研究。结合RCFW结构在往复荷载作用下的响应特性,提出了适用于RCFW结构弹塑性分析的带刚臂纤维截面计算模型,并基于有限元程序ABAQUS提供的用户子程序接口UMAT,开发了混凝土、钢筋两种材料的单轴滞回本构模型,从材料本构层次直接反映构件层次的恢复力特性。通过与RCFW结构低周反复荷载试验结果的对比,验证了计算模型的准确性,模拟曲线较好地反映了RCFW结构在反复加载过程中荷载-位移曲线的承载力和刚度退化及捏拢现象;此外,该计算模型还具有高效的求解效率和数值稳定性,适用于RCFW结构的弹塑性分析和整体抗震性能评估。

Cyclic behavior of a structural system consisting of reinforced concrete frame with infill slit shear wails （RCFW） is studied in this paper. Pseudo-static tests were performed with two one-bay, two-story RCFW specimens built at one-half scale. A fiber section analytical model with rigid arm elements is proposed for this system to research the nonlinear structural behavior under cyclic loadings. Based on the user subroutine interface UMAT provided by the ABAQUS program, a set of uniaxial hysteresis constitutive models for concrete and steel reinforcement is developed, which can directly describe the resilience characteristics of a component from material constitutive models. It is proved correct and applicable of the proposed model through comparing with the experimental results of RCFW specimens under the cyclic loadings, the stiffness and strength degradation and pinch phenomenon can be well described in the calculated load-displacement curves of the RCFW structure under repeated loadings. Besides, the presented analytical model incorporating developed UMAT is efficient and numerically stable, which can he used for elastoplastic analysis of the RCFW structure and for assessment of seismic demand.