碱-硅酸反应和硫酸盐侵蚀复合作用下的混凝土耐久性

Durability of Concrete Subjected to the Combined Action of Alkali-silica Reaction and Sulfate Attack

碱-硅酸反应(ASR)和硫酸盐侵蚀是影响混凝土耐久性的两个重要因素。目前,对于单一因素作用下混凝土劣化过程的研究已有诸多报道,但关于混凝土在碱-硅酸反应和硫酸盐侵蚀复合作用下的损伤失效过程及机理研究却很少。本文介绍了近年来国内外在碱-硅酸反应和硫酸盐侵蚀方面的研究现状,主要阐述了它们各自的膨胀机理和抑制措施。在对Grattan等人试验中得到的膨胀数据、X射线衍射图和扫描电子显微镜图进行分析的基础上,讨论了混凝土在这两种因素复合作用下可能出现的膨胀值变化和强度变化,并提出有效的抑制措施。

Alkali-silica reaction （ASR） and sulfate attack are two of the most important problems on concrete durability. The deterioration of concrete under single destructive action have been broadly investigated, but the damage process and the corresponding mechanisms subjected to combined action of ASR and sulfate attack have rarely studied yet. This pa- per introduces the recent research progress in alkali-silica reaction and sulfate attack achieved home and abroad, and mainly describes the expanding mechanisms and inhibitive measures of each reaction. The probable changes of expansion and strength of concrete subjected to combined action of ASR and sulfate attack are discussed on the base of analyzing experimental results of expansion ,X-Ray diffractogram and SEM micrograph by Grattan et al, and the effective inhibitive measures are also been proposed.