双膨胀中热水泥混凝土的膨胀性能

对双膨胀中热水泥混凝土的自生体积变形以及在钢筋约束下的膨胀应力进行了试验，结果表明：用双膨胀中热水泥拌制的混凝土不仅能产生早期膨胀，也能产生后期膨胀，在约束条件下能产生预压应力，可以比较有效地补偿大坝等大体积混凝土的收缩，增强其抗裂能力，从而提高工程的整体性、安全性和耐久性。结果还表明：双膨胀中热水泥在推迟钙矾石膨胀、加快方镁石膨胀以及提高总的膨胀量等方面，值得继续研究。

Expansive Property of Double-expansive Moderate Heat Portland Cement Concrete

Doubleexpansive moderate heat Portland cement contains both ettringite and periclase expansive sources. In this paper, the autogenous volume deformation and prestress of the concrete prepared with this cement were tested. The results show that concrete prepared with doubleexpansive moderate heat Portland cement has both the early and the late expansion, and can produce prestress when restricted, therefore may compensate the shrinkage of massive concrete projects, dams for example, and hence improve their security, durability. The results also show that the doubleexpansive moderate heat Portland cement should be further studied and improved to retard its ettringite expansion, accelerate its periclase expansion and increase its total expansion magnitude.