碳酸盐环境下水泥基材料性能劣化与腐蚀破坏的研究进展

Research Progress on Performance Degradation and Corrosion Failure of Cement-based Materials in Carbonate Environment

目前,土壤或水中的SO_(4)^(2-)对水泥基材料的腐蚀已被人们所重视,但对碳酸盐环境下水泥基材料的的劣化与腐蚀破坏问题的关注程度较低。相关研究主要集中在碳酸水与水泥基材料中的水化产物氢氧化钙(Ca(OH)_(2))和水化硅酸钙凝胶(C-S-H)进一步反应生成可溶解物质,较少有对碳酸盐环境下其他破坏形式进行研究,例如碳硫硅钙石型破坏。通过综合评述近年来国内外水泥基材料中碳酸性侵蚀和碳硫硅钙石型破坏方面的研究成果,结合我国实际工程中碳酸盐环境下的混凝土劣化与腐蚀破坏案例进行分析,认为碳硫硅钙石型破坏通常发生在我国的西部、西南部地区的隧道初支部位,这可能与喷射混凝土中形成了大量钙矾石有关。最后提出了今后的研究方向,为避免碳酸盐环境下水泥基材料出现劣化与腐蚀破坏提供了理论依据。

At present,the corrosion of SO_(4)^(2-)in soil or water on cement-based materials has been paid more attention,but the problem of performance degradation and corrosion failure in carbonate environment is less attention.Related studies mainly focus on the reaction of carbonated water with calcium hydroxide(Ca(OH)_(2))and calcium silicate hydrate gel(C-S-H)in cement-based materials to generate soluble substances,and few studies focus on other damage forms in carbonate environments,such as thaumasite.This paper reviews the domestic and foreign research results of carbonation erosion and thaumasite on cement-based materials in recent years.Based on the analysis of concrete degradation and corrosion failure in carbonate environment in actual engineering in China,it is considered that the thaumasite is usually found in the initial lining of tunnels in the west and southwest of China,which may be related to the formation of a large number of ettringite in shotcrete.Finally,the future research direction is proposed to provide a theoretical basis for avoiding the deterioration and corrosion failure of cement-based materials in carbo-nate environment.