FRP-UHTCC复合层抗剪增强钢筋混凝土梁受力性能试验研究  

Experimental study on mechanical performance of reinforced concrete beams shear-strengthened with FRP-UHTCC composite

作　　者：郑宇宙 王文炜[3] 戴建国[4] 朱忠锋[3] ZHENG Yuzhou;WANG Wenwei;DAI Jianguo;ZHU Zhongfeng(School of Field Engineering,Army Engineering University of PLA,Nanjing 210007,China;State Key Laboratory of Disaster Prevention & Mitigation of Explosion & Impact,Army Engineering University of PLA,Nanjing 210007 ,China;School of Transportation,Southeast University,Nanjing 210018 ,China;Department of Civil and Environmental Engineering,The Hong Kong Polytechnic University,Hong Kong 999077 ,China)

机构地区：[1]中国人民解放军陆军工程大学野战工程学院,江苏南京210007 [2]中国人民解放军陆军工程大学爆炸冲击防灾减灾国家重点实验室,江苏南京210007 [3]东南大学交通学院,江苏南京210018 [4]香港理工大学土木与环境工程系,香港999077

出　　处：《建筑结构学报》2019年第8期118-126,共9页Journal of Building Structures

基　　金：国家自然科学基金项目(51578135);江苏省博士后基金项目(2018K087B);国家留学基金委公派访学项目(201606090126)

摘　　要：进行了6根纤维增强复合材料(FRP)格栅增强超高韧性纤维水泥基(UHTCC)复合材料加固钢筋混凝土梁的受剪性能试验研究,将FRP格栅增强率和剪跨比作为试验变量,分析各变量对FRP-UHTCC复合增强混凝土梁受剪性能的影响.在试验研究的基础上,给出了FRP-UHTCC复合增强混凝土梁的受剪承载力计算方法.结果表明:加固梁的破坏模式为剪压破坏和受压区混凝土压碎破坏,FRP-UHTCC复合层与混凝土间黏结良好,可以有效抑制混凝土斜裂缝的形成和发展;随FRP格栅增强率的提高,加固梁的受剪承载力得到显著提高;随剪跨比的增加,加固效果更加明显;与未加固的普通混凝土梁相比,加固梁极限荷载的最大提高幅度为61%;受剪承载力理论计算值与试验值吻合较好,可以有效预测FRP-UHTCC复合增强混凝土梁的受剪性能.Six reinforced concrete(RC)beams shear-strengthened with FRP grid reinforced-ultra high toughness cementitious composite(UHTCC)were tested to investigate the shear performance.The reinforcement ratio of FRP grid and the shear-span of the beams were selected as the test parameters to investigate their effects on the mechanical performance of FRP-UHTCC-strengthened RC beams.A shear capacity formula of FRP-UHTCC-strengthened RC beams was proposed based on the test results.The experimental results show that the failure modes of the tested RC beams are shear compression failure in the shear/flexure region and crushing of concrete in the compression zone.Good bonding performance between the FRP-UHTCC composite and the concrete substrate is observed during the test.The propagation of diagonal cracks in the shear/flexure regions is effectively suppressed.The shear capacity of strengthened RC beams is greatly improved with the increase of reinforcement ratio of FRP grid.The reinforcement effect of this strengthening technique is improved with the increase of the shear-span ratio.The maximum increase in shear capacity reached 61%comparing to the non-strengthened reference beam.The proposed formula is validated through the comparisons between the prediction and the measured shear capacity of RC beams shear-strengthened with FRP-UHTCC composite.

关 键 词：钢筋混凝土梁 FRP格栅 超高韧性纤维水泥基复合材料 加固 静力试验 受剪承载力 

分 类 号：U445.7[建筑科学—桥梁与隧道工程] TU317.1[交通运输工程—道路与铁道工程]