【摘要】 文章设计并制作3个2/3缩尺的梁柱节点构造形式为开槽水平搭接的装配整体式混凝土(PC)结构试件,对中柱进行了力-位移控制静力加载的试验。第1个为空间框架子结构,第2个为平面框架子结构,第3个为悬挑结构。根据试验的抗力、位移、应变、裂缝发展及破坏形态等结果对试件的受力变化及抗力机制进行分析。结果表明:压拱作用峰值点之前,空间框架子结构基本可以由平面框架子结构和悬挑结构来叠加等效。由于空间框架平面外横向梁的存在,使得空间框架子结构的压拱效应承载力相比于平面框架子结构的提高11.65%,这主要来源于平面外横向梁的梁机制提供的竖向承载力,但不影响空间框架和平面框架悬链线的开始位移。在悬链线阶段,空间框架子结构平面外横向梁的存在会使悬链线效应降低27.23%,且会使悬链线效应提前近一半的竖向位移结束。在空间框架子结构中发生连续倒塌时,柱头会发生平面外的偏转,会使压拱阶段的峰值相较于平面框架子结构和悬挑结构叠加之和降低4.77%,对悬链线阶段的峰值平面框架子结构和悬挑结构叠加之和降低39.04%。空间框架子结构和平面框架子结构的主要区别源于平面外横向框架梁的影响,会使得空间框架结构出现明显的扭转裂缝,且裂缝发展程度更集中和严重一些,这对结构受力是不利的。更多还原

【Abstract】 In this study, three specimens of two-third scale integrated precast concrete(PC) structures with slotted and lapped splicing of beam-column joints were tested.The first one was the spatial frame substructure, the second one was the planar frame substructure, and the last one was the cantilever structure.The quasi-static loading tests with the force-displacement control were applied to the mid-column.According to the structural performance including the load-carrying capacity, deformation capacity, crack distribution, rebar strain and failure mode, the progressive collapse resistance mechanism of the specimens was analyzed.The test results showed that before the peak point of compressive arch action, the spatial frame substructure can be superimposed by the planar frame substructure and the cantilever structure.Due to the existence of the out-of-plane transverse beam of the spatial frame, the compressive arch action of the spatial frame substructure is increased by 11.65% compared with that of the planar frame substructure.The vertical bearing capacity of the spatial frame substructure is provided by the beam mechanism of the out-of-plane late transverse beam, but the initial displacements of the catenary action of the spatial frame and the planar frame are not affected.In the stage of catenaryaction, the out-of-plane transverse beam of the spatial frame substructure can reduce the catenary action by 27.23%, and complete the catenary action by nearly half of the vertical displacement in advance.In the case of progressive collapse of spatial frame substructure, the out-of-plane deflection of the mid-column head may occur, which may reduce the peak value at the arch compression stage by 4.77% compared with the superposition of planar frame substructure and cantilever structure, and reduce the peak value at the catenary stage by 39.04% compared with the superposition of planar frame substructure and cantilever structure.The main difference between the spatial frame substructure and the planar frame substructure comes from the influence of the out-of-plane transverse frame beam, which may cause obvious torsional cracks and serious development and concentration of cracks in the space frame structure, which shall be adverse to the structural forces.更多还原