粉煤灰掺量对PVA-ECC性能的影响

摘要/Abstract

摘要： 采用粉煤灰替代部分水泥(40%、50%、60%和70%(质量分数))进行聚乙烯醇纤维增强水泥基复合材料(PVA-ECC)的力学性能、韧性、抗渗性能研究;建立了PVA-ECC抗压强度与其极限拉伸强度、弯曲荷载、弯曲韧性指数、挠度及抗渗性能之间的相关性;同时还进行了PVA-ECC渗水高度的统计数据概率分布分析。结果表明,随粉煤灰含量增加,强度逐渐下降,极限拉伸应变逐渐增大,韧性指数、能量吸收能力及跨中挠度逐渐增大,各组别抗渗性能相对于粉煤灰40%含量组别均有所提升。建立抗压强度与其余指标之间相关性,得到一套完整的强度、韧性、抗渗性的相关性理论体系。对PVA-ECC的渗水高度的频率分布直方图采用正态分布进行统计分析,得到渗水高度概率分布,同时计算出平均渗水高度95％置信区间。

关键词: 粉煤灰, PVA-ECC, 力学性能, 韧性指数, 挠度, 抗渗性能

Abstract: The mechanical properties, toughness and impermeability of polyvinyl alcohol fiber reinforced cement-based composites (PVA-ECC) were studied by replacing part of cement (40%, 50%, 60% and 70% (mass fraction)) with fly ash. The correlation between the compressive strength of PVA-ECC and its ultimate tensile strength, bending load, flexural toughness index, deflection and impermeability was established. At the same time, the relationship between the compressive strength of PVA-ECC and its ultimate tensile strength, bending load, flexural toughness index, deflection and impermeability was established statistical data probability distribution analysis. The results show that with the increase of fly ash content, the strength decreases gradually, the ultimate tensile strain increases, the toughness index, energy absorption capacity and mid span deflection increase gradually, the impermeability of each group is improved compared with the 40% fly ash content group. The correlation between compressive strength and other indexes is established, and a complete correlation theoretical system of strength, toughness and impermeability is obtained. The normal distribution is used to analyze the frequency distribution histogram of water seepage height of PVA-ECC, and the probability distribution of seepage height is obtained, and the 95% confidence interval of the average seepage height is calculated.

Key words: fly ash, PVA-ECC, mechanical property, toughness index, deflection, impermeability

中图分类号:

TU528

李晓琴, 周旭, 李世华. 粉煤灰掺量对PVA-ECC性能的影响[J]. 硅酸盐通报, 2020, 39(12): 3783-3790.

LI Xiaoqin, ZHOU Xu, LI Shihua. Effect of Fly Ash Content on Properties of PVA-ECC[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2020, 39(12): 3783-3790.

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