水工混凝土中氧化镁安定掺量的判定方法述评

为了促进外掺MgO混凝土的深入研究和推广应用,本文对现行水工混凝土中MgO安定掺量的五种判定方法进行了对比分析。结果表明,根据现行判定方法确定的MgO外掺量生产的MgO混凝土,其自身体积膨胀量很难满足补偿坝体混凝土温降收缩量的需要。对于如何科学合理地提高水工混凝土的MgO掺量,仍然需要深入研究。同时建议,利用实际工程的原材料和混凝土配合比,开展直接根据混凝土试件的自生体积膨胀量来确定水工混凝土中MgO外掺量的研究。

Review on methods for determining soundness admixing amount of magnesium oxide in hydraulic concrete

In order to prompt the deep research and popularized application of the concrete admixed with magnesium oxide（MgO concrete）, five methods used at present for determining the admixing amount of magnesium oxide in hydraulic concrete are compared and analyzed herein. The result shows that the self-volume expansions of MgO concrete can hardly meet the demands for compensating the temperature-decrease shrinkage of dam concrete when the admixing amount of Mgo is determinde with the current rnethods. Therefore, how to scientifically and reasonably increase the admixing amount of MgO in hydraulic concrete is still necessary to be deeply researched. Meanwhile, it is suggested to carry out the research on determining the admixing amount of MgO directly based on the self-volume expansion of concrete specimen in accordance with the mixing ratio of raw materials and concrete for the actual construction.