双阶受力干式装配梁-柱节点抗震性能试验研究

EXPERIMENTAL INVESTIGATION ON SEISMIC PERFORMANCE OF DOUBLE-STAGE-BEHAVIOR DRY-CONNECTED BEAM-TO-COLUMN JOINT

研究提出了一种双阶受力干式装配梁-柱节点(DADBJ)。该节点的关键组件是摩擦铰(RFH)和预设缝防屈曲钢板(SBRSP),具备2个受力工作阶段和损伤集中易修复的特性。为了验证DADBJ构造的合理性,揭示其双阶段受力工作机理,设计加工了DADBJ试件,以SBRSP的预设缝隙宽度作为试验变量,进行了2个工况的低周往复拟静力试验。结果表明:提出的DADBJ构造实现了预期的双阶段受力特性,第一阶段由RFH提供节点的力学性能,第二阶段由RFH和SBRSP共同提供节点的力学性能;DADBJ的损伤集中于芯板,通过更换SBRSP芯板对节点快速修复,节点的性能可恢复到初始状态;SBRSP的预设缝隙宽度可直接决定DADBJ第二阶段的启动位移;提出的DADBJ双阶屈服荷载理论公式和二阶启动位移理论公式精确度好。该研究可为装配式框架结构和多阶受力型结构的设计和研究提供参考。

This study proposes a double-stage-behavior dry-connected beam-to-column joint(DADBJ),the key component of which is the rotational friction hinge(RFH)and the slitted buckling restrained steel plates(SBRSP).This novel joint features a double-stage mechanical behavior and repairable concentrated damage.In order to verify the rationality of DADBJ and reveal the mechanism of its double-stage mechanical behavior,a test specimen of DADBJ was designed and manufactured.The width of the preset slit of SBRSP was selected as the test variable.Two load cases are conducted under pseudo-static cyclic loading.The test results indicated that the proposed DADBJ achieves its expected double-stage mechanical behavior.In the first stage,the mechanical properties of the joint are provided by RFH.In the second stage,the mechanical properties of the nodes are jointly provided by RFH and SBRSP.The damage of DADBJ is concentrated at the core plates.By replacing the core plates of the SBRSP,the joint could be rapidly repaired with the performance equivalent to the original state.The width of the preset slit of SBRSP directly determines the activation displacement of the second stage of the DADBJ.The proposed theoretical formulas for the double-stage yield loads and the activation displacement of the second stage of the DADBJ are accurate.This research can provide a reference for the research and design of precast concrete frame structures and structures with multi-stage mechanical behaviors.