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。
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.
作者
龚宏伟
江世永
陈进
陶帅
GONG Hong-wei;JIANG Shi-yong;CHEN Jin;TAO Shuai(Department of Military Facility,Army Logistics University of PLA,Chongqing 401331,China;School of Civil Engineering,Chongqing Jiaotong University,Chongqing 400074,China;Unit 91144 of PLA,Qingdao 266031,China)
出处
《玻璃钢／复合材料》
CAS
北大核心
2019年第10期19-25,共7页
Fiber Reinforced Plastics/Composites
基金
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)。
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
polyvinyl alcohol(PVA)fiber
fiber reinforced cementitious composites
bending strength
toughness index
scanning electron microscope(SEM)
