混杂钢纤维UHPC单轴拉伸性能的混杂效应分析  

Hydrid effects of steel fibers on the uniaxial tensile properties of ultra-high performance concrete

作　　者：苏家战 林毅焌 陈宝春[1,2] 黄卿维 SU Jiazhan;LIN Yijun;CHEN Baochun;HUANG Qingwei(College of Civil Engineering,Fuzhou University;Sustainable and Innovative Bridge Engineering Research Center of Fujian Province University,Fuzhou 350116,China)

机构地区：[1]福州大学土木工程学院 [2]可持续与创新桥梁福建省高校工程研究中心,福建福州350116

出　　处：《南昌大学学报（工科版）》2019年第4期358-364,共7页Journal of Nanchang University(Engineering & Technology)

基　　金：国家重点研发计划资助项目(2018YFC0705405)。

摘　　要：为研究混杂不同钢纤维对UHPC轴拉强度、初裂强度和弹性模量的影响,采用优化设计的狗骨试件尺寸,开展了4组,共150个试件的单轴拉伸试验研究。混杂钢纤维参数有:混杂不同长径比圆直纤维、混杂不同长径比弓形纤维,以及混杂不同形状纤维。试验结果表明:在钢纤维总掺量不变下,混杂短圆直和长圆直钢纤维对UHPC材料的抗拉强度、初裂强度和弹模,均能达到正混杂效应;混杂不同长径比的弓形钢纤维,仅提高抗拉强度和弹模,对初裂强度没有明显的影响。其余的混杂纤维试验组,对材料抗拉强度、初裂强度和弹模均显示零效应。因此,采用短圆直钢纤维与大长径比圆直钢纤维或者弓形钢纤维进行混杂,能充分发挥长短纤维各自优势,上述分析结果可为UHPC混杂纤维设计提供参考。In this study,uniaxial tensile testing for a total of 150 specimens,dividing into four sets of test groups were carried out to analyze the hybrid effect on the uniaxial tensile strength,initial crack strength and modulus of elasticity,using the optimized design of dog-bones.The type of hybrid steel fibers included hybrid straight steel fibers with different length-diameter ratios,hybrid hook steel fibers with different length-diameter ratios,as well as hybrid straight and hook steel fibers.For UHPC reinforced with hybrid short and long straight steel fibers could improve its uniaxial tensile strength,initial crack strength and elasticity modulus,achieving its positive hybrid effect.For UHPC reinforced with hybrid long straight fibers or with hybrid long hook fibers could increase its uniaxial tensile strength and elasticity modulus,except for initial crack strength due to without short fiber in UHPC.For the other testing groups,there has no significant hybrid effect on uniaxial tensile strength,initial crack strength and elasticity modulus.The results indicated that short straight fiber should be mixed in UHPC reinforced with long straight and hook fibers which can give full play to their advantages.The results would provide references for design of hybrid fiber in UHPC.

关 键 词：超高性能混凝土 单轴拉伸 钢纤维 初裂强度 混杂效应 

分 类 号：O341[理学—固体力学]