Effectiveness of Surface Coatings Against Intensified Sewage Corrosion of Concrete
来源期刊:Journal Of Wuhan University Of Technology Materials Science Edition2019年第5期
论文作者:孔丽娟 FANG Jun ZHANG Bei
文章页码:1177 - 1186
摘 要:Three different kinds of coatings were coated on the concrete surface, and the changes in appearance, surface roughness, microstructure and components of coatings in artificial sewage were investigated. In addition, the strength, micrograph, mineral compositions and pore structure of concrete specimens after removing coatings were also studied. The results show that epoxy coal tar pitch coating(ECTPC) has the best effect of protecting concrete from the sewage corrosion. After being immersed in sewage for 90 days, the compressive strength of concrete coated with ECTPC is still as high as that of specimen immersed in water, and the cement paste has a high CH content and dense structure with low porosity, which mainly accounts for its excellent barrier property and certain antibacterial function. Cement-based bactericidal coating(CBC) also has good effectiveness to sewage corrosion of concrete. The strength and microstructure of concrete coated with CBC in sewage are still significantly superior to those of uncoated concrete. Although cement-based capillary crystalline waterproofing coating(CCCWC) is a good waterproof material, it is not suitable for the corrosion resistance of concrete in sewage. After 2 months corrosion, almost all of the CH crystals in coating reacted with the metabolic acid substance by microbes. Therefore, the strength and pore structure of concrete coated with CCCWC are only slightly superior to those of uncoated concrete. Overall, the protective effect of cement-based inorganic coatings is relatively poor.
孔丽娟1,2,FANG Jun1,ZHANG Bei1
1. School of Materials Science and Engineering, Shijiazhuang Tiedao University2. Hebei Provincial Key Laboratory of Traffic Engineering Materials, Shijiazhuang Tiedao University
摘 要:Three different kinds of coatings were coated on the concrete surface, and the changes in appearance, surface roughness, microstructure and components of coatings in artificial sewage were investigated. In addition, the strength, micrograph, mineral compositions and pore structure of concrete specimens after removing coatings were also studied. The results show that epoxy coal tar pitch coating(ECTPC) has the best effect of protecting concrete from the sewage corrosion. After being immersed in sewage for 90 days, the compressive strength of concrete coated with ECTPC is still as high as that of specimen immersed in water, and the cement paste has a high CH content and dense structure with low porosity, which mainly accounts for its excellent barrier property and certain antibacterial function. Cement-based bactericidal coating(CBC) also has good effectiveness to sewage corrosion of concrete. The strength and microstructure of concrete coated with CBC in sewage are still significantly superior to those of uncoated concrete. Although cement-based capillary crystalline waterproofing coating(CCCWC) is a good waterproof material, it is not suitable for the corrosion resistance of concrete in sewage. After 2 months corrosion, almost all of the CH crystals in coating reacted with the metabolic acid substance by microbes. Therefore, the strength and pore structure of concrete coated with CCCWC are only slightly superior to those of uncoated concrete. Overall, the protective effect of cement-based inorganic coatings is relatively poor.
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