混掺精细钢纤维/PVA纤维水泥基复合材料的四点弯曲力学性能试验研究  

Experimental study on four-point bending mechanical behavior of cement-based composites with mixed fine steel fiber and PVA fiber

作　　者：刘雁宁[1,2] 张涛 李杉 LIU Yanning;ZHANG Tao;LI Shan(Shanxi Polytechnic College,Taiyuan 030006,China;School of Civil Engineering,Wuhan University,Wuhan 430072,China)

机构地区：[1]山西职业技术学院,山西太原030006 [2]武汉大学土木建筑工程学院,湖北武汉430072

出　　处：《混凝土》2022年第9期16-19,共4页Concrete

基　　金：国家自然科学基金项目(51778507);纤维复材网格增强水泥基复合材料加固锈蚀钢筋混凝土梁受力性能研究。

摘　　要：通过四点弯曲试验研究精细钢纤维/聚乙烯醇(PVA)纤维混掺对水泥基复合材料的弯曲性能的影响,试验考虑PVA纤维体积掺量为1.0%,精细钢纤维体积掺量为0.4%、0.8%、1.2%、1.6%,分析不同掺量对试件破坏形态、荷载-挠度曲线、韧性指数、裂缝分布的影响规律。结果表明:精细钢纤维与PVA纤维混掺后,试件的荷载-挠度曲线呈双峰状,破坏后呈多缝开裂,裂缝宽度减小。体积掺量为0.8%精细钢纤维与1%PVA纤维的混掺试件,其抗弯强度提高了138%,韧性指数I_(5)、I_(10)、I_(20)分别提高了8.5%、18.3%、25.9%,混掺纤维可有效提高水泥基复合材料的抗弯性能。By conducting four-point bending experiments,it investigate the effect of blending polyvinyl alcohol fibers and fine steel fibers on the bending performance of the cement-based material.1.0% PVA fiber and four volume contents of fine steel fiber(0.4%,0.8%,1.2% and 1.6%)are considered in the experiment for studying the influence of the fine steel fiber content on failure modes,load-deflection curves,toughness indexes and crack distribution.Experimental results indicate that the specimens with mixed fibers have bimodal load-deflection curves,and presents multiple crack propagation under external loading,with smaller crack width.The bending performance of specimen with 0.8% fine steel fiber and 1% PVA fiber is improved,with an increase of 138% on its bending strength,and 8.5%,18.3%,25.9% increments on its bending toughness indexes of I_(5),I_(10)and I_(20),respectively.It is found that the bending performance of the cement-based composite can be improved by blending fine steel fiber and PVA fiber.

关 键 词：工程材料 混杂纤维 试验研究 弯曲力学性能 精细钢纤维 聚乙烯醇纤维 

分 类 号：TU528.572[建筑科学—建筑技术科学]