钢筋聚丙烯纤维混凝土深梁受弯承载力试验研究  

Experimental Tests of Flexural Bearing Capacity of Polypropylene Fiber Reinforced Concreted Deep Beams with Reinforcement

作　　者：付敏 夏冬桃 颜帅 朱峰 FU Min;XIA Dongtao;YAN Shuai;ZHU Feng(School of Civil Engin.,Architecture and Environment,HubeiUniv.of Tech.,Wuhan 30068,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

出　　处：《湖北工业大学学报》2020年第1期55-58,74,共5页Journal of Hubei University of Technology

基　　金：国家自然科学基金(51108164)。

摘　　要：为研究聚丙烯纤维对高性能混凝土深梁受弯性能的影响,采用三分点加载方式对不同聚丙烯纤维掺量(掺量分别为0、0.055%、0.11%、0.165%)的混凝土深梁的受弯性能进行对比试验研究,分析聚丙烯纤维对深梁工作性能和破坏形态、混凝土应变、深梁挠度及纵筋应变的影响。研究结果表明:聚丙烯纤维体积掺量为0.11%时可使试件裂后变形能力得到很大改善,其混凝土弯拉应变超过2000με,屈服荷载提高30%~50%,受弯过程具备明显的纤维强化阶段,聚丙烯纤维的强化作用在纵筋屈服后充分发挥,极限受弯承载力提高58%。当聚丙烯纤维掺量为0.055%或0.165%时,对高性能混凝土深梁的受弯性能影响不明显。本文提出了钢筋聚丙烯纤维混凝土深梁的正截面受弯承载力计算公式,计算值与试验值吻合较好。In order to study the effect of polypropylene fibers on the flexural properties of high performance concrete deep beams,three-point loading method was used to compare the flexural properties of concrete deep beams with different polypropylene fibers(0,0.055%,0.11%,0.165%,respectively).The effects of polypropylene fiber on the working performance and failure mode of deep flexural beams,concrete strain,deep flexural beam deflection and longitudinal reinforcement strain were analyzed.The results show that when the volume fraction of polypropylene fiber is 0.11%,the deformation ability of the specimens after cracking can be greatly improved.The concrete tensile strain exceeds 2000με,and the yield load increases by 30%to 50%.The loading process has a distinct fiber strengthening stage,and the strengthening effect of the polypropylene fiber is fully exerted after the longitudinal reinforcement yields,and the ultimate flexural capacity is increased by 58%.When the content of polypropylene fiber is 0.055% or 0.165%,the flexural performance of high performance concrete deep beams is not significantly affected.The calculation formula of normal section flexural strength of polypropylene fiber reinforced concreted deep beams with reinforcement was proposed.The calculated value agrees well with the experimental value.

关 键 词：聚丙烯纤维 深梁 抗裂 受弯承载力 

分 类 号：TU312[建筑科学—结构工程]