碱矿渣胶凝材料的开裂性能研究

Study on Cracking Properties of Alkali Slag Cementitious Material

碱矿渣胶凝材料是具有高强、高耐久性的胶凝材料,但其收缩大,易开裂,是阻碍其广泛应用的主要原因。通过圆环法研究了MgO膨胀剂、聚丙烯纤维和减缩剂单掺或复掺对碱矿渣胶凝材料开裂性能的影响。研究结果表明:单掺MgO膨胀剂对碱胶凝体系抗裂不利,减缩剂和聚丙烯纤维的掺入能够有效延缓裂缝的形成,减小开裂面积。

Alkali slag cementitious material is a material with high strength and high durability.However,its great shrinkage and easy-cracking properties are the main reasons to restrict its wide application.The ring crack testing method is used to study the effect of single or multiple additions of MgO expansion agent,polypropylene fiber and shrinkage reducing agent on the cracking properties of alkali slag cementitious material.The study results show that the single addition of MgO expansion agent is not good for cracking resistance of alkali cementitious system,but the additions of shrinkage reducing agent and polypropylene fiber can effectively delay the formation of cracks and reduce a cracking area.