钢-PVA混杂纤维高性能混凝土断裂性能与弯曲韧性试验
Experimental on Fracture Properties and Flexural Toughness of High Performance Concrete with Steel-PVA Hybrid Fiber
许成祥 1金旭 2许奇琦 2肖良丽1
作者信息
- 1. 武汉科技大学城市建设学院,武汉 430065;武汉科技大学高性能工程结构研究院,武汉 430065
- 2. 武汉科技大学城市建设学院,武汉 430065
- 折叠
摘要
为了研究钢-聚乙烯醇(polyvinyl alcohol,PVA)混杂纤维对高性能混凝土(high performance concrete,HPC)的增强增韧效果,以钢纤维体积分数、PVA纤维体积分数和矿粉掺量为三因素,采用正交试验,设计并制作16组试件,进行四点加载和三点加载弯曲试验,获取了荷载(P)-跨中挠度(δ)曲线和荷载(P)-裂缝张口位移(crack mouth opening displacement,CMOD)曲线,测定了 28 d龄期后的弯曲韧性和断裂性能等.研究表明:混凝土中掺入钢纤维或PVA纤维,P-δ曲线和P-CMOD曲线都变得更加饱满,对其有较为明显的增强增韧效果;特别是当两种纤维和一定量的矿粉掺入混凝土中,曲线下降段趋势变得更加平缓,混掺纤维高性能混凝土试件比单掺纤维混凝土试件具有更好的变形能力,掺入1.5％的钢纤维、0.2％的PVA纤维和20％的矿粉的效果最佳,对弯曲韧性和断裂性能的提升最为显著,具有不错的正混杂效应.
Abstract
In order to study the strengthening and toughening effect of steel-PVA(polyvinyl alcohol)blended fibers on HPC(high performance concrete),16 sets of specimens were designed and fabricated by using steel fiber volume fraction,PVA fiber volume frac-tion and mineral powder dosing as triple factors,and four-point loading and three-point loading bending tests were conducted to obtain load(P)-mid-span deflection(δ)curves and load(P)-CMOD(crack mouth opening displacement)curves,the flexural toughness and fracture properties after 28 days of age were determined.The study shows that:the P-δ curve and P-CMOD curve become more full when the concrete is mixed with steel fiber or PVA fiber,which has a more obvious enhancement and toughening effect;especially when the 2 fibers and a certain amount of mineral powder are mixed into the concrete,the trend of the falling section of the curve be-comes more gentle,and the mixed fiber high performance concrete specimens have better deformation ability than the single fiber con-crete specimens,mixed with 1.5％of steel fiber,0.2％of PVA fiber and 20％of mineral powder has the best effect,the most signifi-cant improvement of bending toughness and fracture performance,with a good positive mixing effect.
关键词
钢-PVA混杂纤维/弯曲韧性/断裂性能/混杂效应/正交试验Key words
steel-PVA hybrid fibers/flexural toughness/fracture performance/hybrid effects/orthogonal test引用本文复制引用
基金项目
湖北省高等学校优秀中青年科技创新团队计划(T2022002)
出版年
2024
NETL
NSTL
万方数据