纤维增强水泥基复合材料弯曲性能与纤维作用机理研究

玻璃钢/复合材料 ›› 2019, Vol. 0 ›› Issue (10): 19-25.

纤维增强水泥基复合材料弯曲性能与纤维作用机理研究

龚宏伟¹, 江世永^1,2, 陈进¹, 陶帅³

1.陆军勤务学院军事设施系,重庆401331;
2.重庆交通大学土木工程学院,重庆400074;
3.中国人民解放军91144部队,青岛266031

收稿日期:2019-03-18 出版日期:2019-10-28 发布日期:2019-10-28
作者简介:龚宏伟(1994-),男,硕士研究生,主要从事结构工程及建筑新材料方面的研究,hechuan7hao@163.com。
基金资助:
重庆市高校优秀成果转化资助重点项目(KJZH14220);重庆市社会民生科技创新专项项目(cstc2015shmszx30006)

STUDY ON BENDING PERFORMANCE AND MECHANISM OFFIBER REINFORCED CEMENTITIOUS COMPOSITES

GONG Hong-wei¹, JIANG Shi-yong^1,2, CHEN Jin¹, TAO Shuai³

1.Department of Military Facility, Army Logistics University of PLA, Chongqing 401331, China;
2.School of Civil Engineering, Chongqing Jiaotong University, Chongqing 400074, China;
3.Unit 91144 of PLA, Qingdao 266031, China

Received:2019-03-18 Online:2019-10-28 Published:2019-10-28

摘要/Abstract

摘要： 通过四点弯曲试验,研究了5组不同PVA纤维掺量的纤维增强水泥基复合材料试件的弯曲性能。试验结果表明,纤维掺量对试件的弯曲性能有着显著影响,掺入适量纤维可以明显改善试件的脆性破坏特征,裂缝呈现出细而密的特点。当纤维体积掺量V_f不超过2.0%时,初裂弯曲强度、峰值弯曲强度、等效弯曲强度值和韧性指标均随纤维掺量的增加而增大;而V_f为2.5%的试件流动性能较差,部分纤维结团,弯曲强度较V_f=2.0%组试件有所下降。结合荷载-挠度曲线,采用电镜扫描定性分析了复合材料中纤维的作用机理,对影响纤维桥联作用发挥的因素进行了研究。

关键词: PVA纤维, 纤维增强水泥基复合材料, 弯曲强度, 韧性指标, 电镜扫描

Abstract: To study the bending properties of fiber reinforced cementitious composite, five groups of specimens with different PVA fiber content were studied by four-point bending test. The experimental results show that the fiber content has a significant effect on the bending properties of specimens. Appropriate amount of fiber can significantly improve the brittleness of specimens, and crack is small and dense. When the fiber volume V_f≤2.0%, the initial cracking bending strength, peak bending strength, equivalent bending strength and toughness index increase with the increase of fiber content. For specimens with V_f=2.5%, the flowability is poor and some fiber agglomerates. As a result, the bending strength of specimens with V_f=2.5% is lower than specimens with V_f=2.0%. Combined with the load-deflection curve, the mechanism of fiber in the composite was qualitatively analyzed by scanning electron microscope, and the factors affecting the fiber bridging effect were studied.

Key words: polyvinyl alcohol (PVA) fiber, fiber reinforced cementitious composites, bending strength, toughness index, scanning electron microscope (SEM)

中图分类号:

TB332

龚宏伟, 江世永, 陈进, 陶帅. 纤维增强水泥基复合材料弯曲性能与纤维作用机理研究[J]. 玻璃钢/复合材料, 2019, 0(10): 19-25.

GONG Hong-wei, JIANG Shi-yong, CHEN Jin, TAO Shuai. STUDY ON BENDING PERFORMANCE AND MECHANISM OFFIBER REINFORCED CEMENTITIOUS COMPOSITES[J]. Fiber Reinforced Plastics/Composites, 2019, 0(10): 19-25.

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