反复荷载作用下钢筋再生混凝土框架边节点的破坏机理  

Failure mechanism of exterior reinforced recycled concrete joint under cyclic loading

作　　者：孙祯[1] 郑建岚[1,2,3] SUN Zhen;ZHENG Jianlan(College of Civil Engineering,Fuzhou University,Fuzhou,Fujian 350108,China;Coordinative Innovation Center for Environmentally Friendly and Energy Saving HPC,Fuzhou,Fujian 350108,China;College of Engineering,Fujian Jiangxia University,Fuzhou,Fujian 350108,China)

机构地区：[1]福州大学土木工程学院,福建福州350108 [2]福建省环保节能型高性能混凝土协同创新中心,福建福州350108 [3]福建江夏学院工程学院,福建福州350108

出　　处：《福州大学学报（自然科学版）》2020年第1期76-82,共7页Journal of Fuzhou University(Natural Science Edition)

基　　金：国家自然科学基金资助项目(51578153)

摘　　要：为研究反复荷载作用下钢筋再生混凝土框架边节点的破坏机理,以再生粗骨料取代率为研究变量,设计4个框架边节点试件进行拟静力实验.观察节点区域的裂缝发展形态,获取节点混凝土应变、箍筋应变、梁柱纵筋应变随加载位移的变化曲线,并分析再生粗骨料取代率变化对试件破坏形态的影响规律.结果表明:节点剪力主要由混凝土斜压杆机构承担,通裂后则由钢筋构成的桁架机构和斜压杆机构共同承担;节点箍筋明显早于梁纵筋和柱纵筋发生屈服,体现节点剪切变形的受力特征;再生粗骨料的存在会加剧试件的裂缝发展、增大钢筋和混凝土的应变,其中以取代率为70%的试件最为严重.In order to study the failure mechanism of exterior reinforced recycled concrete joint under cyclic loading,four exterior joint specimens were designed considering different recycled coarse aggregate replacement ratios,and subjected to cyclic loading.During the pseudo-static test,concrete cracking of joint core area was observed,concrete strain,stirrup strain,beam and column longitudinal reinforcement strain were obtained,and the failure modes of specimens under different recycled coarse aggregate replacement ratios were analyzed.The results showed that:the shear force was undertaken by concrete through diagonal compression strut mechanism before cracking,and then transferred to joint stirrup.The joint stirrup yielded before the beam and column longitudinal reinforcement reached yield condition,representing shear failure mode of joint.Recycled coarse aggregates may affect the cracking trend of exterior joint,and increase the concrete and steel strain,especially for specimen RJ70.

关 键 词：框架边节点 再生混凝土 再生粗骨料 取代率 破坏机理 

分 类 号：TU375.4[建筑科学—结构工程]