挤压纤维增强水泥板及复合梁抗弯与耐久性能.pdf

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第3卷第6期
土木建鏡与环境
Vol 31 No, 6
2009年12月
ournal of Civil, Architectural & Environmental Engineering
Dec、2009
挤压纤维增强水泥板及复合梁抗弯与耐久性能
张君,李启宏,侯东伟
(清华大学土木工程系结构工程与振动教育部重点实验室,北京100084)
摘要:研究了水灰比、纤维种类、掺量和水泥基材対挤压成型纤维水泥板及其复合梁的力学性能
与耐久性能的影吻。结果表明捲加纤维后板材韧性有显著改善;PVA纤维增强顽材当纤维掺量达
1.7%时表现应变硬化,出现多点开栗;PP纤维则虽现应变软化。两种纤增强水泥基材料性能的
差异是由于纤維自身性能的不同。以纤维增强板为底板,制作的纤维板/混凝土复合梁的极限荷載
和相应浇度,与普通混凝土梁相比都得以改善;同时与普通混凝士梁相比,复合梁的抗氣离子渗透
性能更好。
关键词:挤压成型;釬维増强水泥板;カ学性能;耐久性能
中图分类号:TU528文献标志码;A文章编号:1674-4764(2009)06-0081-95
Mechanical Properties and Durability of Extruded Fiber Reinforced
Cement Mortar Board and Its Composite Beam
ZHANG Jun, L Qi-hong, HOU Dong-wei
Department of Civil Engineering, Key Laboratory of Structural Engineering and Vibration of Education Ministry, Tsinghua
University, Beijing 100084, P. R. China)
Abstract: The effect of water to cement ratio, fiber types and content, cement types on the bending
performance of the extruded fiber reinforced cementitious board were studied. And it was found that
polyvinyl alcohol ( PVA) filers can significantly improve the ductility of the board compared with
polypropylene (PP) fibers. As PVA fiber content achicved 1.7%3, the strain hardening and multiple
cracking were occurred on the extruded board, while strain-softening were shown on PP fiber reinforced
cemcnt board. The differenc betweer the two kinds of board was from the differences of the mechanical
properties of the two fibers. In addirion, taking the fiber reinforced extruded board as base, the ultimate
bending strength, as well as and the corresponded deflection and the resistant to chloride iron penetrating
was improved for a composite beam with fiber board and concrete compared with those of traditiona
concrete beam
Key words: extrusion molding; fiber reinforced cement board; mechanical property durability
普通水泥基材具有很高的抗压强度、较大的刚变软化特性,人们开始借助微观、细观力学手段研究
度,但存在收缩大、抗拉强度低、极限延伸率小以及具有应变硬化特性的水泥基材料,其中基于细观力
抗冲击性差等缺点。将纤维加人水泥基材中可以改学设计的高韧性纤维増强水泥基复合材料
善水泥基材的抗拉、抗冲击性能,起到阻裂,提高其( Engineered: ementitious Composite-ECC)是当前
初性的作用。为了克服传统混凝土材料的脆性和应比较成功的具有应变硬化特性的水泥基材料之
收稿日期:2009-06-1
基金项目:国家自然科学基金资助项目(50878119)
作者简介:张君(1962),男?教授,博上生导师,主要从事纤维増强混凝上研究,(E-mnail)junz(@tsinghua.cdu.cn