摘要
纤维增强复合材料筋(Fiber Reinforced Polymer,简称FRP)具有超高的抗拉强度,有望在恶劣环境下代替钢筋使用;但是GFRP筋弹性模量较小,导致GFRP筋增强混凝土结构变形和裂缝宽度较大,影响正常使用。超高韧性纤维增强水泥基复合材料(Engineered Cementitious Composites,简称ECC)作为一种高性能土木工程建筑材料,与普通混凝土相比具有超高韧性、应变硬化、多级开裂和细密裂缝特征。GFRP筋增强ECC结构能够实现较小的裂缝宽度和超高耐久性能,因此具有良好的应用前景。然而,FRP筋与ECC之间的黏结性能尚不清楚,相关文献较少。拟开展FRP筋与不同强度和韧性的ECC材料的黏结性能试验研究,通过中心拉拔试验,测试其拔出承载力和端部黏结滑移,描述试验现象,分析其黏结滑移曲线特征。分析了ECC材料不同强度和韧性对于黏结性能的影响。研究发现:ECC材料和FRP筋的中心拉拔试验荷载-滑移曲线由上升段,下降段和波浪状的残余段3部分组成;ECC材料较高的强度和韧性对FRP与ECC的黏结强度都发挥着有利的作用;FRP与ECC的黏结强度是ECC强度和韧性综合影响的结果,其并不随着单一因素的提高而提高。
Fiber reinforced polymer(FRP)is expected to take the place of steel bars and used in harsh environment,since it has superior tensile strength.But GFRP tends to have small elastic modulus,resulting in structural deformation and crack width,affecting normal use.As a high-performance civil engineering building material,the engineered cementitious composites(ECC)is characterized by its superior high toughness,strain hardening characteristics compared with ordinary concrete,multi-stage cracking and fine cracks.The ECC structure with GFRP reinforcement can achieve smaller crack width and high durability,so it has a good application prospect.However,the bonding properties between FRP tendons and ECC are not yet clear,and there are few related documents.It carried out the experimental study on the bond performance of FRP bars and ECC materials with different strength and toughness,measured the pull-out capacity and the slippage at the end of the bond slip through the center pull-out test,and described the test phenomenon and analyze the bond slip curve characteristics.By analyzing the effect of different strength and toughness of ECC materials on the bonding performance,some conclusions have been obtained.The study finds that the central pullout test load-slip curve of ECC material and FRP tendon is composed of three parts,ascending segment,descending segment and wavy residual segment.The higher strength and toughness of ECC materials play an advantageous role in the bond strength between FRP and ECC.The bond strength between FRP and ECC is the result of the combined effect of ECC strength and toughness,which does not increase with the increase of single factor.
作者
司豆豆
张普
孙新茂
丁亚进
韩月一
吴凌旭
唐国斌
SI Doudou;ZHANG Pu;SUN Xinmao;DING Yajin;HAN Yueyi;WU Lingxu;TANG Guobin(School of Civil Engineering,Zhengzhou University,Zhengzhou 450001,China;Henan Transportation Research Institute Co.,Ltd.,Zhengzhou 450015,China)
出处
《混凝土》
CAS
北大核心
2019年第8期108-111,共4页
Concrete
基金
国家自然科学基金项目(51508519)
河南省产学研项目(162107000024)
河南省教育厅高等学校重点项目(14B560014,15A560040)
作者简介
第一作者:司豆豆(1997-),男。联系地址:河南省郑州市高新区科学大道100号郑州大学土木工程学院(450001)联系电话:13275972465;通讯作者:张普(1982-),男,副教授。联系电话:13523009543。
