氧化镁微膨胀混凝土的变形特性研究

Deformation Characteristic Research of Mangnesium Oxide Microexpanded Concrete

本文通过长达十余年的自生体积变形试验研究,阐明了氧化镁水泥的膨胀特性与机理,并着重论述了微膨胀混凝土的体积变形,证明氧化镁水泥混凝土的长期变形性能是稳定的。通过工程验证,氧化镁的膨胀特性,掺合料质量与掺量都是可控制的。在工程中应用氧化镁延迟性微膨胀水泥,是坝体混凝土温控防裂的极其有效措施,也是理想的防裂新材料。

By means of the concrete autogenous volume deformation experiment research in a long time of more than ten years, the paper clarifies the characteristics and mechanism of magnesium oxide cement expansion, and discusses with emphasis the volume deformation of microexpanded concrete to prove the stability of long-term deformation behaviour of magnesium oxide cement concrete. It is verified by experiments for projects that the expansion characteristics of magnesium oxide, admixture quality and quantity are controllable. The research indicates that the influence of temperature on deformation rate and value of magnesium oxide cement concrete is significant and increases as temperature rises, and the deformation is irreversible. The research makes known that the deformation of outside admixed magnesium oxide cement concrete is heightened as the admixture quantity increases, and its stability time is far moved up than that with cement containing high quantity of magnesium.