ECC+BFRP格栅复合加固钢筋混凝土梁弯曲抗冲击性能试验研究  

Experimental investigation of flexural performance of reinforced concrete beams strengthened with ECC and BFRP grid under impact loading

作　　者：赵德博 黄峰 陈湘生[1,2] 崔宏志[1,2] 包小华[1,2] 陈斌[1,2] Zhao Debo;Huang Feng;Chen Xiangsheng;Cui Hongzhi;Bao Xiaohua;Chen Bin(College of Civil and Transportation Engineering,Shenzhen University,Shenzhen 518060,China;Key Laboratory of Coastal Urban Resilient Infrastructures(MOE),Shenzhen University,Shenzhen 518060,China;Guangzhou Municipal Group Co.,Ltd.,Guangzhou 510060,China)

机构地区：[1]深圳大学土木与交通工程学院,广东深圳518060 [2]深圳大学滨海城市韧性基础设施教育部重点实验室,广东深圳518060 [3]广州市市政集团有限公司,广东广州510060

出　　处：《土木工程学报》2025年第4期24-36,共13页China Civil Engineering Journal

基　　金：国家自然科学基金重大项目(52090084);国家自然科学基金面上项目(52178292);广东省自然科学基金面上项目(2023A1515010224)。

摘　　要：文章对超高韧性水泥基材料(ECC)+玄武岩纤维复材(BFRP)格栅复合加固钢筋混凝土(RC)梁的静力与冲击动力行为进行试验研究,共进行4根梁的三点弯曲静力试验和9根梁的落锤冲击试验,考虑ECC强度、混凝土强度、FRP格栅种类、FRP格栅厚度等影响因素。试验中测量了支座反力、冲击力、加速度及挠度时程响应,并采用高速摄像机和非接触式数字成像测试系统(DIC)分析冲击过程中加固梁表面的动态应变。试验结果表明,随着加固层BFRP格栅配置率增大,相同冲击能量下加固梁表现出更小的挠度变形和界面剥离长度。当采用低强度ECC作为加固层基体时,提高梁体混凝土强度对界面黏结性能有所削弱,但可通过同时提高加固层ECC与梁体混凝土强度以增强界面黏结性能。采用基于平截面假定的简化模型可以较为准确地计算ECC+BFRP格栅复合加固RC梁的抗冲击承载力,但界面黏结滑移使得加固梁冲击最大挠度大于相同承载力的钢筋混凝土梁。In this work,the static and impact dynamic behavior of reinforced concrete(RC)beams strengthened by the composite of Engineered Cementitious Composite(ECC)and Basalt Fiber-reinforced Polymer(BFRP)grids were experimentally investigated.Four beams subjected to three-point bending static loads and nine beams subjected to drop hammer impact loads were tested,with the influencing factors such as ECC strength,concrete strength,FRP grid type and FRP grid thickness being considered.In the tests,the support reaction force,impact force,acceleration,and time history of deflection response were measured,and the dynamic strain on the strengthened beam surface during impact was analyzed by using high-speed video cameras and the digital imaging correlation(DIC).The test results demonstrated that with the increase of the thickness of the BFRP grid in the strengthening layer,the strengthened beams presented smaller deflection deformation and interface peeling length under the same impact energy.When low-strength ECC was used as the strengthening layer matrix,the interfacial bonding performance was weakened by increasing the concrete strength of the beams,while the interfacial bonding performance was enhanced by simultaneously increasing the strength of both the ECC and the concrete of the beams.The plane cross-section assumption-based simplified model can predict the impact resistance of strengthened beam with reasonable accuracy,but the interface debonding resulted in the peak deflections of strengthened beams generally larger than those of unstrengthened RC beams with equal resistances.

关 键 词：ECC材料 BFRP 落锤冲击试验 抗冲击加固 界面剥离 

分 类 号：TU375.1[建筑科学—结构工程]