冲击作用下CFRP修复损伤RC叠合梁动力性能试验研究  

An experimental study on dynamic performance of CFRP-repaired RC composite beams under impact

作　　者：何庆锋[1] 岳泪阳 毛佳伟 HE Qingfeng;YUE Leiyang;MAO Jiawei(College of Civil Engineering,Hunan University,Changsha 410082,China)

机构地区：[1]湖南大学土木工程学院,长沙410082

出　　处：《振动与冲击》2021年第4期171-178,共8页Journal of Vibration and Shock

基　　金：既有工业建筑非工业化改造技术研究(2016YFC0701308);中央高校基本科研业务费(2016YFC0701400)。

摘　　要：采用落锤冲击试验机,进行了现浇梁、叠合梁以及碳纤维增强复合材料(carbon fiber reinforced polymer,CFRP)修复的损伤梁的动力性能对比试验。冲击作用下试件破坏形态以及冲击力与变形时程曲线表明,叠合面在一定程度上抑制了跨中裂缝向上开展的趋势,损伤修复后的叠合梁在冲击荷载下的破坏程度明显减轻,初始损伤减弱了梁跨中位移的滞后现象;相比完好梁,现浇与叠合修复梁抗冲击承载力有着同等程度的提高。基于有效应变计算的修复梁承载能力提升与试验结果的对比显示,CFRP能有效改善并增强构件的整体受力性能,在冲击作用下对构件的实际抗力贡献大于原有构件承载力与FRP受拉能力简单叠加时的理论抗力贡献。A dynamic performance comparison test of cast-in-situ beams,laminated beams,and CFRP-repaired damaged beams was carried out using a drop hammer impact tester.The failure mode of the specimen under impact and the time history curves of impact force and deformation indicate that the superimposed surface inhibits the upward trend of the mid-span crack to a certain extent,the damage degree of the composite beam after damage repair is obviously reduced when subjected to impact load,the hysteresis of displacement in the beam span is significantly reduced by the initial damage,the impact bearing capacity of the cast-in-place and the superimposed repaired beam has the same degree of improvement.The comparison between the bearing capacity improvement of the repaired beam and the test results based on the effective strain calculation shows that CFRP can effectively improve and enhance the overall mechanical performance of the component,when subjected to impact loads,CFRP contributes more to the actual resistance of the component than the theoretical resistance which is a simple superposition of the bearing capacity of the original component and the FRP tensile capacity.

关 键 词：叠合梁 初始损伤 CFRP 落锤试验 

分 类 号：TH375.1[机械工程—机械制造及自动化]