氧化镁膨胀剂的研究现状

Review on the research of MgO-based expansive agent

与以钙矾石作为膨胀源的传统的膨胀剂相比,MgO膨胀剂具有水化需水量少、膨胀过程可调控、水化产物稳定的优点,适用于补偿大体积混凝土温降收缩、混凝土自收缩和干燥收缩,可广泛应用于水工建筑、机场道面、公路、地下工程等。本文着重介绍了目前关于MgO膨胀剂的膨胀机理、膨胀性能、工业化生产、安定性评估、工程应用等方面的现状。在此基础上提出了当前关于MgO膨胀剂的研究应用过程中所急需解决的问题和研究方向。

Compared to the traditional expansive agents for which the expansion results from the formation of ettringite,many advantages of MgO-based expansive agent(MEA) exist,such as lower requirement of water for hydration,designable expansion properties and physical-chemistry stable hydration products.MEA could be used not only in compensating the thermal shrinkage of massive concrete,but also in compensating the autogenous shrinkage and drying shrinkage of concrete.It could be used in the hydraulic buildings,concrete pavement,underground building and so on.The expansion mechanism,expansion properties,industrial production,soundness evaluation and the application of MEA were summarized in this paper.The problems existed about the research and application of MEA were also discussed.