可更换耗能连接组件的装配式混凝土柱脚抗震性能试验研究  

Experimental study on seismic behavior of precast concrete column base with replaceable energy dissipation connectors

作　　者：章锦洋 吴京[1] 谢鲁齐[1] 李春雨 朱云青 ZHANG Jinyang;WU Jing;XIE Luqi;LI Chunyu;ZHU Yunqing(Key Laboratory of Concrete and Prestressed Concrete Structures of the Ministry of Education,Southeast University,Nanjing 211189,China;Changzhou Municipal Bureau of Housing and Urban-Rural Development,Changzhou 213022,China;Key Laboratory of Roads and Railway Engineering Safety Control(Shijiazhuang Tiedao University),Ministry of Education,Shijiazhuang 050043,China)

机构地区：[1]东南大学混凝土及预应力混凝土结构教育部重点实验室,江苏南京211189 [2]常州市住房和城乡建设局,江苏常州213022 [3]道路与铁道工程安全保障省部共建教育部重点实验室(石家庄铁道大学),河北石家庄050043

出　　处：《建筑结构学报》2022年第11期51-62,共12页Journal of Building Structures

基　　金：国家重点研发计划(2019YFC1509305);国家自然科学基金项目(51978165);河北省自然科学基金项目(E2021210096)。

摘　　要：为使装配式混凝土结构在强震作用下达到损伤集中的效果,增强装配式混凝土结构的震后可修复性,提出一种可更换耗能连接组件(REDC)的装配式混凝土柱脚。设计并制作了1个足尺REDC装配式混凝土柱脚,通过改变柱设计轴压比、REDC核心耗能钢板厚度等参数,开展了4个工况下的拟静力试验。研究结果表明:加载过程中柱脚始终表现出稳定的滞回特性和较高的延性,低轴压比(n=0.3)下呈饱满的梭形滞回环,高轴压比(n=0.8)下滞回环有一定捏缩;除高轴压比下柱底钢套筒局部区域竖向压应变接近屈服应变外,柱脚始终保持完好,塑性变形集中于REDC核心耗能钢板内;混凝土柱身处于微损伤状态,表现为柱脚卸载至初始位置后可闭合的水平向弯曲裂缝;核心耗能钢板断裂前,在5%水平位移角下经历了至少25次加载循环,表现出良好的低周疲劳性能;核心耗能钢板的失效模式为疲劳断裂,断裂位置均位于屈服段中部或屈服段与过渡段交界处。REDC核心耗能钢板的实测变形量与理论计算结果基本一致,验证了理论分析的准确性,可用于该种装配式混凝土柱脚设计。A type of precast concrete column base with replaceable energy dissipation connectors(REDCs)was proposed for controlling damage of precast concrete structures during large earthquakes and improving the repairability of precast concrete structures after earthquakes.A full-scale specimen of precast concrete column base with REDCs was designed and constructed for four quasi-static tests.The concerned variables include the design axial compression ratio of the column and the thickness of the core plates of REDCs(REDC-CPs).The research results reveal that the column base exhibits stable hysteretic property and high ductility during the loading process.The spindle shaped hysteretic loop is quite plump when the axial compression ratio is low(n=0.3),but a certain amount of pinching occurs with high axial compression ratio(n=0.8).Except that the vertical compressive strain of partial regions in the steel tube of the column base is close to yield strain with high axial compression ratio,the column base remains intact,and the plastic deformation is concentrated on the REDC-CPs.The concrete column is at the stage of micro-damage since the concrete cracks are horizontal flexural cracks which can close by themselves when the specimen is unloaded to its original position.Besides,the REDC-CPs do not fracture after more than twenty-five repeated cycles at a 5.0%lateral drift ratio,showing their good low cycle fatigue performance.The failure mode of REDC-CPs is the fatigue fracture in the middle of the yielding segment or at the junction of the yielding segment and the transition segment.The measured deformation of REDC-CPs is basically consistent with theoretical results,verifying the accuracy of theoretical analysis,which can be used for the design of this type of precast concrete column base.

关 键 词：装配式混凝土柱脚 可更换耗能连接组件 轴压比 拟静力试验 抗震性能 低周疲劳特性 

分 类 号：TU375.403[建筑科学—结构工程] TU352.11