NRC-UHPC界面抗剪性能试验研究  

Experimental Study on Shear Behavior between NRC‑UHPC Interface

作　　者：陈振侃 李军生 时权 方浩圳 莫凡 姜海波[3] CHEN Zhenkan;LI Junsheng;SHI Quan;FANG Haozhen;MO Fan;JIANG Haibo(Operating Branch,Guangzhou Communications Investment Group Co.,Ltd.,Guangzhou,Guangdong 511430,China;Guangzhou Guangming Expressway Co.,Ltd.,Guangzhou,Guangdong 511430,China;School of Civil and Transportation Engineering,Guangdong University of Technology,Guangzhou,Guangdong 510006,China)

机构地区：[1]广州交通投资集团有限公司营运分公司,广东广州511430 [2]广州广明高速公路有限公司,广东广州511430 [3]广东工业大学土木与交通工程学院,广东广州510006

出　　处：《中外公路》2024年第6期176-184,共9页Journal of China & Foreign Highway

基　　金：国家自然科学基金资助项目(编号:51778150);广州交通投资集团有限公司科技项目(编号:YXGL211GZ1890)。

摘　　要：为了探讨植筋螺杆直径以及超高性能混凝土(UHPC)浇筑方法对普通钢筋混凝土(NRC)与UHPC间抗剪受力性能的影响,该文设计了两组共6个推出试件,并进行抗剪性能试验。试验结果表明:NRC-UHPC界面混凝土黏结力失效后,植筋螺杆仍可继续发挥抗剪作用,从而使荷载达到峰值后的试件破坏过程呈现出延性特征;对于使用直径为12 mm和16 mm螺杆的试件,随着螺杆直径的增大,试件的抗剪承载力和界面破坏时的延性均得到提升。在采用后浇UHPC层的试件(ZJ组)中,当螺杆直径为16 mm时,其破坏形态介于剪断与拔出之间。而使用高强砂浆作为填充材料的试件(GJ组)的界面,在荷载-滑移曲线上表现出的延性低于后浇UHPC试件(ZJ组)。此外,基于试验结果,对比了ACI、AASHTO和FIB规范给出的抗剪公式发现,同时考虑了剪-摩擦和销栓效应的FIB公式能较为准确地描述试件的界面抗剪承载力。因此,建议采用FBI规范来计算使用UHPC加固的植筋NRC结构的抗剪承载力。In order to investigate the effect of the screw diameter of planted bars and ultra-high performance concrete(UHPC)pouring method on the shear behavior of normal reinforced concrete(NRC)and UHPC,two groups of six push-out specimens were designed for shear behavior tests.The results show that after the failure of the concrete bonding force in the NRC‑UHPC interface,the screw can maintain shear behavior so that the failure process of the specimen after the load reaches the peak shows ductile characteristics.For specimens with screw diameters of 12 mm and 16 mm,greater screw diameter indicates higher shear capacity of the specimens and ductility after interface failure.When the screw diameter is 16 mm,the specimens in Group ZJ using the post-pouring UHPC layer fail in a mode of partial shearing off and partial pulling out.The ductility at the interface of the specimens in Group GJ using high-strength mortar as filling material is lower than that of the specimens in Group ZJ using the post-pouring UHPC layer in terms of the load-slip curve.Based on the experimental results,the shear behavior formulas of ACI,AASHTO,and FIB specifications are compared.The FIB formula,which considers both the shear friction and the bolt pin effect,can accurately describe the interfacial shear capacity of the specimens.Therefore,it is recommended to use the FBI specification to calculate the shear capacity of NRC structures reinforced with UHPC.

关 键 词：桥梁工程 抗剪性能 推出试验 UHPC 植筋 延性 

分 类 号：U444[建筑科学—桥梁与隧道工程]