钢-聚丙烯混杂纤维混凝土与既有混凝土的黏结劈拉性能试验研究  

Experimental research on splitting tensile property between steel-polypropylene HFRC and existing concrete

作　　者：夏冬桃 郑挚 吴昊 XIA Dongtao;ZHENG Zhi;WU Hao(Civil Engineering,Architecture and Environment,Hubei University of Technology,Wuhan 430068,China;Office Affairs Center,Changjiang Navigation Administration,Wuhan 430014,China)

机构地区：[1]湖北工业大学土木建筑与环境学院,湖北武汉430068 [2]长江航务管理局机关事务中心,湖北武汉430014

出　　处：《混凝土》2022年第9期132-136,共5页Concrete

基　　金：国家自然科学基金(51108164);湖北省创力结构工程研发基金。

摘　　要：为研究不同掺量的混杂纤维及界面剂对新老混凝土黏结性能的影响,对12组混杂纤维混凝土(聚丙烯纤维体积掺量为0.11%,多锚点钢纤维体积掺量分别为0.8%和1.2%)与既有混凝土的立方体黏结试件(150 mm×150 mm×150 mm)进行劈拉性能试验,并对黏结界面取样进行SEM扫描,分析不同纤维掺量及界面剂对新老混凝土的界面黏结强度和破坏形式等的影响以及混杂纤维在黏结面的作用机理。试验结果表明:单纤维及钢-聚丙烯混杂纤维的掺入均能提高试件的黏结劈拉强度,其中钢纤维体积掺量1.2%的混杂纤维混凝土试件提高幅度最大,相较于普通混凝土提高幅度最大为26%;涂抹环氧界面剂试件的黏结劈拉强度均大于无界面剂试件,涂抹环氧界面剂能有效提高混凝土试件的黏结劈拉性能;混杂纤维掺入后能有效改善黏结界面区的孔隙结构,提高界面黏结性能。In order to study the influence of different content of hybrid fiber and interfacial agent on the bond performance of new to old concrete,the splitting tensile properties of 12 groups of hybrid fiber concrete(polypropylene fiber volume content is 0.11%,multi anchor steel fiber volume content is 0.8% and 1.2%)and existing concrete cube bond specimens(150 mm×150 mm×150 mm)were tested,SEM scanning was carried out for the adhesive interface samples.The influence of different fiber content and interfacial agent on the interfacial bond strength and failure mode of new and old concrete is analyzed.The experimental results show that the addition of single fiber and steel and polypropylene hybrid fibers can improve the bond splitting tensile strength of the specimens,and the increase range of the hybrid fiber concrete with 1.2% volume fraction is the largest,it′s 26% higher than that of OC.The bond splitting tensile strength of the specimens coated with epoxy interfacial agent is greater than that of the unbounded agent specimen,and the epoxy interfacial agent can effectively improve the bond splitting tensile strength.The bond splitting tensile properties of concrete specimens were studied.The pore structure of interfacial region can be improved and improve the interface bonding performance by the incorporation of hybrid fibers.

关 键 词：混杂纤维混凝土 既有混凝土 黏结劈拉性能 界面剂 SEM 

分 类 号：TU528.572[建筑科学—建筑技术科学]