预制钢筋增强ECC壳-混凝土组合柱轴压力学性能  

Axial compressive behaviour of precast steel reinforced ECC shell-concrete composite column

作　　者：王瑾[1] 许维炳[2] 杜修力[2] 丁梦佳 陈彦江[2] 闫晓宇[3] 徐小蓉 WANG Jin;XU Weibing;DU Xiuli;DING Mengjia;CHEN Yanjiang;YAN Xiaoyu;XU Xiaorong(School of Water Resources and Hydropower Engineering,North China Electric Power University,Beijing 102206,China;Faculty of Architecture,Civil and Transportation Engineering,Beijing University of Technology,Beijing 100124,China;School of Engineering,The Open University of China,Beijing 100039,China)

机构地区：[1]华北电力大学水利与水电工程学院,北京102206 [2]北京工业大学城市建设学部,北京100124 [3]国家开放大学理工教学部,北京100039

出　　处：《复合材料学报》2024年第9期5083-5097,共15页Acta Materiae Compositae Sinica

基　　金：国家自然科学基金项目(52108428,52178446);中央高校基本科研业务费专项资金(2023MS067);北京工业大学重点实验室校外开放课题(2022B02)。

摘　　要：为经济、有效、合理地应用工程水泥基复合材料(Engineered cementitious composites,ECC)以提升钢筋混凝土(Reinforced concrete,RC)柱的力学性能,本文发展了一种预制钢筋增强ECC壳-混凝土组合柱,设计制作了该型组合柱的试验模型和全RC、ECC柱对照模型,通过轴压力学性能试验对比分析了预制钢筋增强ECC壳-混凝土组合柱和全RC、ECC柱轴压力学性能的差异,重点探究了ECC壳厚度和箍筋间距对预制组合柱轴压力学性能的影响规律,并以此构建了考虑箍筋和ECC壳组合约束的组合柱轴心受压承载力计算公式。结果表明:相比于RC柱,预制钢筋增强ECC壳-混凝土组合柱与ECC柱均表现出延性破坏特征,破坏时未出现ECC保护层剥落以及预制ECC壳与混凝土内芯分离等现象。随ECC壳厚度增加,预制组合柱的峰值荷载和峰值位移增加,初始刚度和延性系数降低;预制ECC壳的引入显著提高了试件的延性和耗能能力,本文ECC壳厚度变化范围内,预制组合柱的延性系数是RC柱的1.13~1.35倍,累积耗能是RC柱的2.13~2.46倍;箍筋间距减小,预制组合柱的承载力提高,峰后延性和耗能能力显著增加。组合柱的轴压承载能力应考虑预制ECC壳的约束作用,相关承载力计算公式可用于该型组合柱的轴压承载能力计算。To economically,effectively and reasonably apply engineered cementitious composites(ECC)on improving the mechanical properties of reinforced concrete(RC)column,a novel composite column consisting of precast concrete core and precast steel reinforced ECC shell(SECC-PC composite column)was developed in this paper.SECC-PC composite column specimens as well as the contrast pure RC column and pure ECC column specimens were designed and manufactured.The axial compression tests were conducted to investigate the axial compression behaviours of the specimens.And the influence law of ECC shell thickness and stirrup spacing on the axial compression behaviours of the specimens was systematically analyzed.Based on this,the calculation equation of axial compressive bearing capacity of the composite columns considering the additional confinement effect of the stirrup and ECC shell was established.The results show that,compared with the RC column,the SECC-PC composite columns and ECC column exhibit obvious ductile failure characteristic,and no ECC spalling and no segregation phenomena between the precast ECC shell and concrete core occur at failure state.With the ECC shell thickness increasing,the peak load and displacement of the precast composite columns increase,while the relevant initial stiffness and ductility coefficient decrease.The incorporation of the precast ECC shell can significantly improve the ductility and energy dissipation capacity of the specimens.Within the designed ECC shell thickness in this study,the ductility coefficients and the accumulated energy dissipation of the precast composite columns are 1.13-1.35 times and 2.13-2.46 times larger than that of the RC column.With the stirrup spacing decreasing,the bearing capacity improves,while the post-peak ductility and energy dissipation capacity of the specimens improve remarkably.The axial compressive bearing capacity of the composite column should take the constraint effect of the prefabricated ECC shell into account.The relevant bearing capacity calculation

关 键 词：工程水泥基复合材料 预制ECC壳-混凝土组合柱 ECC壳厚度 箍筋间距 轴压性能 约束机制 

分 类 号：TU528.58[建筑科学—建筑技术科学] TB333[一般工业技术—材料科学与工程]