PVA纤维增强纳米SiO_(2)水泥基复合材料弯曲韧性研究

Study on flexural toughness properties of PVA fiber reinforced nano-SiO_(2) cement composites

以初始弯曲韧度比Re,p、弯曲韧度比Re,k作为表征纳米水泥基复合材料弯曲韧性的评价指标,通过9组配合比共27个小梁试件的三分点加载弯曲试验,探究了PVA纤维掺量对普通水泥基复合材料和纳米SiO2水泥基复合材料弯曲韧性的影响。结果表明,随着PVA纤维掺量的增加,PVA纤维增强普通水泥基复合材料和纳米SiO2水泥基复合材料的弯曲韧性指标都呈现出先增大后减小的趋势,且均在PVA纤维掺量为1.2%时达到最大值,此时2种水泥基复合材料的荷载-挠度曲线最饱满。

The initial bending toughness ratio Re,p bending toughness ratio Re,k are used as evaluation indexes to characterize the bending toughness of nano-cement-based composites.The influences of PVA fiber dosage on the bending toughness of ordinary cement-based composite and nano-cement-based composites are explored through a three-point loading bending test of 27 trabecu-lar specimens mixed with PVA fiber in 9 mix proportions.The results show that the flexural toughness indexes of PVA fiber rein-forced ordinary cement-based composite and reinforced nano-SiO2 cement-based composite both show a trend of increasing first and then decreasing with the increase of PVA fiber content,and the PVA fiber content is 1.2%when the maximum value is reached.At this time,the load-deflection curves of the two cement-based composite materials are the fullest.