PVA纤维对混凝土抗裂与增韧效应影响的研究进展

Progress of PVA fibers research in improving crack resistance and toughness of concrete

对高抗拉强度和高弹性模量的聚乙烯醇(PVA)纤维在影响混凝土抗裂与增韧效应方面的研究进展和存在的问题进行了综述。在改善抗裂性能方面,PVA纤维提高了混凝土的抗塑性开裂能力和极限拉伸值等性能,我国大型水利水电及水运工程已经开始采用PVA纤维提高混凝土的抗裂性;在韧性提高方面,研究主要集中在纤维掺量、混凝土强度、钢筋配筋率等因素对混凝土弯曲韧性的影响上。认为应在PVA纤维增韧材料的设计理论、裂缝形成与扩展的机制、PVA纤维混凝土本构方程等方面开展进一步的研究。

The progress of research on and existing problems with polyvinyl alcohol ( PVA) fibers with high tensile strength and high elastic modulus in improving crack resistance and toughness of concrete are summarized. In terms of crack resistance improvement, PVA fiber improves the resistance to plastic cracking and ultimate tensile strength of concrete. Projects in hydraulic engineering, hydropower engineering, and water transport engineering in China have begun using PVA fibers to improve crack resistance of concrete. In terms of toughness improvement, research mainly focuses on the effect of fiber content, concrete strength, the reinforcement ratio, and other factors in the flexural toughness of concrete. The theory of design of toughening materials, mechanisms of crack formation and propagation, and constitutive equations of PVA fiber-reinforced concrete should be further investigated.