箱形柱芯筒式双法兰刚性连接节点平面框架拟静力试验研究

QUASI-STATIC TESTING OF CORE-TUBE BOX-COLUMN STEEL FRAMES WITH DOUBLE FLANGED RIGID CONNECTIONS

  • 摘要: 提出一种箱形柱芯筒式双法兰刚性连接节点平面纯框架及减震框架,设计了两榀5层原型结构,对两榀原型结构试验子结构进行0.7倍缩尺,完成拟动力试验之后继续进行拟静力试验,该文对拟静力试验中两榀框架的滞回性能、各典型部位应变变化、刚度退化及耗能能力等进行对比研究。试验结果表明,当层间位移角为0.005 rad(1/200)时,纯框架和减震框架整体均保持弹性状态,中间柱型摩擦阻尼器开始摩擦耗能,占结构总耗能的71.3%;当层间位移角为钢结构弹塑性位移角限值0.02 rad(1/50)时,两榀试验结构滞回曲线均呈双线性,节点域均无塑性产生,减震框架柱脚塑性发展较纯框架更小;当层间位移角为0.04 rad(1/25)时,滞回曲线均更为饱满,节点域仍无塑性产生,纯框架柱脚屈曲更为明显。拟静力试验中两榀框架连接节点可靠,中间柱型摩擦阻尼器通过摩擦耗能,有效延缓减震框架主体结构塑性发展,减震框架结构刚度、耗能能力、抗震性能优于纯框架。

     

    Abstract: This paper proposes two types of box-column steel frames with double flanged rigid connections, namely, the plane core-tube frame and the damped core-tube frame. Correspondingly, two prototypes of 5-story structures were designed. Quasi-static testing on 0.7-scale subsystems was conducted following a pseudo-dynamic test of the subsystems. Structural properties including the hysteretic performance, strain variations of typical members, degradation of structural stiffness, energy dissipation are analyzed and compared. The results indicate that both frames remain elastic while the intermediate columns with friction dampers consume 71.3% of the dissipated energy in the building at the stage of 0.005 rad. (1/200) interfloor drift. As the drift reaches the threshold of 0.02 rad. (1/50) of the elastoplastic angles of steel structures, the hysteretic curves of the two substructures are bilinear. The panel zones of the connections remain elastic. Plasticity of a column base of the damped frame develops more slowly than that of the plane frame. As the drift ratio goes to 0.04 rad. (1/25), the areas of the hysteretic curves are enlarged without plastic deformation in the panel zones. The base buckling of the plane frame is severer than that of the damped frame. The connections of the two frames are reliable. The intermediate column with friction dampers effectively restrains the plasticity development in the damped frame through frictional energy dissipation in the quasi-static test. The stiffness, energy-dissipation capacity and seismic performance of the damped frame are much better than those of the plane frame.

     

/

返回文章
返回