集料中含碱矿物的分解及对碱-集料反应的影响

化学组成中含有Na,K的含碱矿物,如各种长石、云母等,普遍存在于混凝土集料中。作为地质演变的主要证据,这些含碱矿物在酸性、中性以及弱碱性条件下的分解析碱反应得到了证实。但是处于水泥混凝土中的强碱性复杂环境下,箕料中含碱矿物是否能够分解并析出大量的碱,是否由此而导致混凝土碱-集料反应(alkali-aggregate reaction, AAR)破坏的加剧一直以来成为混凝土碱集料反应研究中的一个悬而未决的问题。针对此问题进行了大量的研究,但至今并未得到统一的认识。本文对混凝土中含碱矿物的碱析出的研究进行了评述,指出了现有研究存在的不足, 并对今后的研究方向提出了意见。

Decomposition Reaction of Alkaline Minerals in Concrete Aggregate and the Effect on AAR

The alkaline minerals which contain Na and/or K, such as feldspars, micas, etc., exist commonly in the aggregate. As main evidence of geologic succession, the decomposition and alkali release of alkaline minerals in acidic, neutral or slightly alkaline solution were affirmed. Though it was studied carefully, the question about the decomposition and alkali releasing of alkaline minerals in concrete and its effect on AAR were not answered uniformly. In this paper, studies on alkali released from alkaline mineral in concrete were summarized, the insufficiencies in these researches were pointed out, and some ideas about developing study on this question were given also.