纤维增强磷酸镁水泥刨花板性能研究

关键字：水泥刨花板,磷酸镁水泥,PVA纤维,抗弯强度,断裂能

（1.武汉理工大学 交通学院，湖北 武汉  430063；2.香港理工大学 土木与环境工程系，香港  999077）

    摘要：水泥刨花板是由水泥、木材、化学添加剂为原材料制成的绿色环保建材，利用磷酸镁水泥为胶凝材料可使其快速固化成型，在此基础上研究聚乙烯醇（PVA）纤维对板材抗弯强度以及断裂能的影响。结果表明，PVA纤维能显著提高磷酸镁水泥刨花板的抗弯强度和断裂能，在等体积纤维添加时，直径较小的PVA纤维具有更好的强度提高效果；此外，表面油剂处理的PVA纤维能更好地提高磷酸镁水泥刨花板的韧性；微观分析发现，在板材破坏界面处，表面油剂处理的PVA纤维多为拔出状态，而未处理的PVA纤维主要表现为拉断状态。
    关键词：水泥刨花板；磷酸镁水泥；PVA纤维；抗弯强度；断裂能
    中图分类号：TU525.2；TU528.58        文献标识码：A        文章编号：1001-702X（2017）06-0073-05

Study on performance of fiber reinforced magnesium phosphate cement-bonded particleboards
LI Shuang1，2，LI Zhida1，WANG Lei2，ZENG Chaohua2
（1.School of Transportation，Wuhan University of Technology，Wuhan 430063，China；2.Department of Civil and Environmental Engineering，The Hong Kong Polytechnic University，Hong Kong 999077，China）

    Abstract：Cement-bonded particleboard is a kind of environmental-friendly building material composed of cement，wood and chemical admixtures. Magnesium phosphate cement could accelerate setting and hardening of particleboards. Based on this，the effects of polyvinyl alcohol（PVA） fiber on the bending strength and fracture energy of particleboards were investigated. The experimental results showed that PVA fiber can significantly enhance the bending strength and fracture energy of magnesium-phosphate particleboards. Under the condition of equal volume fraction，PVA fiber with smaller diameter showed higher improvement effect on the strength. In addition，oiled PVA fiber presented larger enhancement on toughness of particleboards when compared to unoiled fiber. On the fractured interface，microscopic analysis indicated that most oiled PVA fiber was pulled out，while most unoiled fiber was ruptured during failure of particleboards.
    Key words：cement-bonded particleboard，magnesium phosphate cement，PVA fiber，bending strength，fracture energy