摘要
为进一步明确新旧地铁车站接驳改造过程中用于连接新建和既有结构的新旧混凝土连接节点力学行为,设计了6个新旧混凝土连接节点试件,并测试了其受弯和弯剪性能,分析了不同植筋排布方案和弯剪工况对节点变形性能、承载能力、开裂行为和破坏模式的影响,结合测试结果揭示了节点的全过程力学行为机理,并以此为基础提出了纯弯和弯剪耦合作用下的节点承载力计算方法。结果表明:以植入钢筋和既有结构预留钢筋为主要连接措施的新旧混凝土连接节点整体工作性能良好;纯弯和弯剪耦合作用下节点均在既有结构保留墙段处破坏,其承载力主要由植筋的拉力和销栓力协同受压区混凝土提供。提出的新旧混凝土连接节点承载力计算方法可较好地预测纯弯和弯剪耦合作用下节点的承载力;在满足相关规范植筋要求的前提下,可通过增大植筋直径来减少植筋数量。
To further clarify the mechanical performance of the old-to-new concrete connecting joints used to link old and new structures during renovation,six old-to-new concrete connecting joint specimens were designed and their bending and shear-bending performance were tested.The effects of different post-installed rebar arrangement schemes and bending-shear conditions on the deformation performance,load-bearing capacity,cracking behavior and failure modes of the joints were analyzed.Based on the full-process mechanical behavior of the joints,the load-bearing mechanism of the joints was revealed and a method for calculating the load-bearing capacity of the joints under both bending and bending-shear coupled conditions was proposed.The results show that the old-to-new concrete connecting joints,primarily connected by embedded post-installed and reserved rebars in the existing structures,exhibit good integrated performance.Under both bending and bending-shear coupled conditions,the failure location of the joints is the preserved wall section in the existing structure.The bearing capacity of the joints is mainly provided by the tension and dowel action of the planted rebars in concert with the concrete in the compression zone.The proposed method for calculating the load-bearing capacity of the old-to-new concrete connecting joints,can be used to predict the joint load-bearing capacity under both bending and bending-shear coupled conditions.Under the premise of meeting the requirements of design codes,larger diameter post-installed rebars are recommended to reduce the number of rebars required.
作者
张素梅
罗贤志
向阳欢
李爱东
张晨明
吴逸凡
张西巡
ZHANG Sumei;LUO Xianzhi;XIANG Yanghuan;LI Aidong;ZHANG Chenming;WU Yifan;ZHANG Xixun(School of Civil and Environmental Engineering,Harbin Institute of Technology(Shenzhen),Shenzhen 518055,China;Guangdong Provincial Key Laboratory of Intelligent and Resilient Structures for Civil Engineering,Harbin Institute of Technology(Shenzhen),Shenzhen 518055,China;China Railway Design Corporation,Tianjin 300308,China)
出处
《建筑结构》
北大核心
2024年第19期157-168,共12页
Building Structure
基金
中国铁路设计集团有限公司科技开发项目(2022CJ0102)。
关键词
地铁车站
接驳改造
新旧混凝土连接节点
植筋
剪跨比
受力性能
metro station
renovation
old-to-new concrete connecting joint
post-installed rebar
shear span ratio
mechanical performance
