配置核心钢管的钢筋混凝土柱-钢骨混凝土梁组合框架力学性能非线性分析

NONLINEAR ANALYSIS ON MECHANICAL PERFORMANCE OF FRAME STRUCTURES COMPOSED OF STEEL REINFORCED CONCRETE BEAMS AND STEEL-TUBE REINFORCED CONCRETE COLUMNS

  • 摘要: 基于两榀配置核心钢管的钢筋混凝土柱-钢骨混凝土梁组合框架试件在水平低周往复荷载作用下的试验结果,分别采用三维实体单元和纤维梁柱单元建立了试验框架数值模型,并开展力学性能和滞回全过程分析。考察了试验框架的破坏形态和内置钢骨架、钢筋骨架及预应力筋的应力状态。对组合框架开展滞回性能参数分析,考察了柱长细比、轴压比、梁柱内型钢截面抵抗矩和配筋率、柱内钢管的含钢率、钢管约束系数和径厚比、混凝土强度和预应力度的影响,并在大量参数分析的基础上建立了单层单跨组合框架的恢复力模型。结果表明:基于三维实体单元的数值模型可较为直观的反应试件的破坏形态;计算所得组合框架滞回曲线较为饱满,具有良好的耗能能力,当轴压比超过0.6以后,组合框架的位移延性才有所变小,变形能力变差;建立的滞回模型可对组合框架在水平荷载下的滞回性能进行可靠的预测。

     

    Abstract: Based on the test results of two frame specimens composed of steel-tube reinforced concrete columns and steel reinforced concrete beams under cyclic horizontal loading, the numerical models of the specimens are established by three-dimensional entity elements and fiber beam-column elements, respectively. The mechanical performance and whole process of the hysteresis are studied. The failure mode and the state of stress of steel skeleton, reinforcement skeleton and the prestressing tendons in the specimens are also observed. The parametric analysis of the hysteretic behavior of the frame specimens are conducted. The influence of column slenderness ratio, axial compression ratio, sectional modules and reinforcement ratio, ratio of steel tube in column, steel tube confinement factors, radius-thickness ratio, concrete strength and prestressing level on the composite frame are observed. The hysteretic model of single-storey and single-span composite frame are proposed on the basis of a large number of parametric analysis. The results indicates that the failure modes could be simulated intuitively by the numerical model established by three dimensional entity elements; the hysteretic curves calculated show a plump shape and favorable energy-dissipating capacity in the frame; when the axial compression ratio is bigger than 0.6, the displacement ductility of the frame decreases; the proposed hysteretic model by parametric analysis could give reliable prediction of the composite under horizontal loading.

     

/

返回文章
返回