海洋环境下混凝土的硫酸盐腐蚀机理
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摘要
海水中存在的硫酸根离子传输至混凝土内部将导致其腐蚀破坏。针对矿粉掺量0～65%的C40引气混凝土进行海洋潮汐区、大气区和水下区腐蚀1～2a,测试其水溶和酸溶硫酸根离子浓度分布;分析水泥净浆中的腐蚀产物类型及含量。试验结果表明:海洋不同腐蚀区带混凝土中硫酸根离子传输量及传输深度排序为:潮汐区>水下区>大气区。混凝土中反应硫酸根离子与总硫酸根离子的关系服从线性函数分布,反应量占总硫酸根离子量的90%以上,反应的硫酸根离子量随腐蚀龄期增加而增加。海洋潮汐区和水下区生成的腐蚀产物量高于大气区,主要是钙矾石和石膏;海洋大气区暴露混凝土的腐蚀产物为钙矾石。对于P.I.52.5水泥制备的C40混凝土而言,掺加65%的矿粉有助于提升混凝土抗海洋硫酸根离子侵蚀能力。
Sulfate ions in seawater penetration into concrete would lead to damage of concrete in marine environment.In this paper,the air entraining concrete with 0-65% of GGBS content was exposed to marine tidal zone,atmosphere zone and submerged zone for 1～2 a.The water-soluble and acid-soluble sulfate ions profile were tested,and the corrosion products of cement paste in marine environment was analyzed.The experimental results shown that the order of the migration sulfate ion content and transmission depth of concrete exposed to different corrosion zones was in order of:tidal zone>submerged zone> atmosphere zone.The relationship between reactive sulfate ion and total sulfate ion in concrete could be expressed as a linear function.The reacted sulfate ion content accounted for more than 90% of total sulfate ions,and the amount reaction sulfate ion increased with the corrosion time.The amount of corrosion products including ettringite and gypsum were generated in pastes exposed to tidal zone and submerged zone.The corrosion product of concrete exposed to the atmosphere zone was only ettringite.For C40 concrete prepared with P.I.52.5 cement,cement replacement by 65% GGBS helps to improve the capacity of concrete to sulfate ion attack in marine environment.
Sulfate ions in seawater penetration into concrete would lead to damage of concrete in marine environment.In this paper,the air entraining concrete with 0-65% of GGBS content was exposed to marine tidal zone,atmosphere zone and submerged zone for 1～2 a.The water-soluble and acid-soluble sulfate ions profile were tested,and the corrosion products of cement paste in marine environment was analyzed.The experimental results shown that the order of the migration sulfate ion content and transmission depth of concrete exposed to different corrosion zones was in order of:tidal zone>submerged zone> atmosphere zone.The relationship between reactive sulfate ion and total sulfate ion in concrete could be expressed as a linear function.The reacted sulfate ion content accounted for more than 90% of total sulfate ions,and the amount reaction sulfate ion increased with the corrosion time.The amount of corrosion products including ettringite and gypsum were generated in pastes exposed to tidal zone and submerged zone.The corrosion product of concrete exposed to the atmosphere zone was only ettringite.For C40 concrete prepared with P.I.52.5 cement,cement replacement by 65% GGBS helps to improve the capacity of concrete to sulfate ion attack in marine environment.
引文
[1]CWIRZEN A,SZTERMEN P,HABERMEHL-CWIRZEN K.Effect of Baltic seawater and binder type on frost durability of concrete[J].Journal of Materials in Civil Engineering,2014,26(2):283-287.
[2]GONZALEZ M A,IRASSAR E F.Ettringite formation in low C3A Portland cement exposed to sodium sulfate solution[J].Cementand Concrete Research,1997,27(7):1061-1071.
[3]张云清,余红发,孙伟,等.MgSO4腐蚀环境作用下混凝土的抗冻性[J].建筑材料学报,2011,14(5):698-702.ZHANG Y Q,YU H F,SUN W,et al.Frost resistance of concrete under action of magnesium sulfate attract[J].Journal of Building Materials,2011,14(5):698-702.(in Chinese)
[4]杨全兵,杨钱荣.硫酸钠盐结晶对混凝土破坏的影响[J].硅酸盐学报,2007,35(7):877-880.YANG Q B,YANG Q R.Effects of saltcrystalllization of sodium sulfate on deterioration of concrete[J].Journal of the Chinese Ceramic Society,2007,35(7):877-880.(in Chinese)
[5]JIN Z Q,SUN W,ZHANG Y S.Interaction between sulfate and chloride solution attack of concrete with and without fly ash[J].Cement and Concrete Research,2007,37(8):1223-1232.
[6]金祖权,孙伟,赵铁军,等.在不同溶液中混凝土对氯离子的固化程度[J].硅酸盐学报,2009,7(7):1068-1072.JIN Z Q,SUN W,ZHAO T J,et al.Chloride binding in concrete exposed to corrosive solutions[J].Journal of the Chinese Ceramic Society,2009,7(7):1068-1072.(in Chinese)
[7]SOIVE A,ROZIERE E,LOUKILI A.Parametrical study of the cementitious materials degradation under external sulfate attack through numerical modeling[J].Construction and Building Materials,2016,112:267-275.
[8]LIU Z Q,DENG D H,SCHUTTER G D,et al.Chemical sulfate attack performance of partially exposed cement and cement+fly ash paste research article[J].Construction and Building Materials,2012,28(1):230-237.
[9]SISOMPHON K,FRANKE L.Evaluation of calcium hydroxide contents in pozzolanic cement pastes by a chemical extraction method[J].Construction and Building Materials,2011,25(1):190-194.
[10]卢峰,金祖权,孙朋朋,等.混凝土粉末对硫酸根离子的固化能力[J].腐蚀与防护,2012,33(11):932-934.LU F,JIN Z Q,SUN P P,et al.Influnence of concrete powders on binding capacity of sulfate ions[J].Corrosion Science and Protection Technology,2012,33(11):932-934.(in Chinese)
[11]金祖权,陈惠苏,赵铁军,等.混凝土在硫酸盐冻融中的损伤与离子传输[J].建筑材料学报,2015,18(3):494-498.JIN Z Q,CHEN H S,ZHAO T J,et al.Damage and ion penetration in concrete subjected to sulfate frost[J].Journal of Building Materials,2015,18(3):494-498.(in Chinese)
[12]杨全兵.混凝土盐冻破坏机理(I)毛细管饱和度和结冰压[J].建筑材料学报,2007,10(5):522-527.YANG Q B.Mechanisms of deicer-frost scaling of concrete(I)-capillary-cptake degree of saturation and ice-formation pressure[J].Journal of Building Materials,2007,10(5):522-527.(in Chinese)
[13]马志鸣,赵铁军,李绍纯,等.海洋潮汐环境下混凝土硫酸盐侵蚀机理研究[J].海岸工程,2014,33(1):31-36.MA Z M,ZHAO T J,LI S C,et al.Study on mechanism of concrete sulfate erosion in ocean tidal environment[J].Coastal Engineering,2014,33(1):31-36.(in Chinese)
[14]何小芳,缪昌文,洪锦祥,等.水泥浆体的热分析动力学[J].东南大学学报(自然科学学版),2011,41(3):601-605.HE X F,MIAO C W,HONG J X,et al.Thermal analysis kinetics of cement paste[J].Journal of Southeast University(Natural Science),2011,41(3):601-605.(in Chinese)
[15]颜哩哩,周文,尤迁,等.基于DSC-TG的钙矾石半定量分析方法[J].新型建筑材料,2015,42(2):41-43.YAN L L,ZHOU W,YOU Q,et al.Semi quantifying ettringite by DSC-TG method[J].New Building Material,2015,42(2):41-43.(in Chinese)
[2]GONZALEZ M A,IRASSAR E F.Ettringite formation in low C3A Portland cement exposed to sodium sulfate solution[J].Cementand Concrete Research,1997,27(7):1061-1071.
[3]张云清,余红发,孙伟,等.MgSO4腐蚀环境作用下混凝土的抗冻性[J].建筑材料学报,2011,14(5):698-702.ZHANG Y Q,YU H F,SUN W,et al.Frost resistance of concrete under action of magnesium sulfate attract[J].Journal of Building Materials,2011,14(5):698-702.(in Chinese)
[4]杨全兵,杨钱荣.硫酸钠盐结晶对混凝土破坏的影响[J].硅酸盐学报,2007,35(7):877-880.YANG Q B,YANG Q R.Effects of saltcrystalllization of sodium sulfate on deterioration of concrete[J].Journal of the Chinese Ceramic Society,2007,35(7):877-880.(in Chinese)
[5]JIN Z Q,SUN W,ZHANG Y S.Interaction between sulfate and chloride solution attack of concrete with and without fly ash[J].Cement and Concrete Research,2007,37(8):1223-1232.
[6]金祖权,孙伟,赵铁军,等.在不同溶液中混凝土对氯离子的固化程度[J].硅酸盐学报,2009,7(7):1068-1072.JIN Z Q,SUN W,ZHAO T J,et al.Chloride binding in concrete exposed to corrosive solutions[J].Journal of the Chinese Ceramic Society,2009,7(7):1068-1072.(in Chinese)
[7]SOIVE A,ROZIERE E,LOUKILI A.Parametrical study of the cementitious materials degradation under external sulfate attack through numerical modeling[J].Construction and Building Materials,2016,112:267-275.
[8]LIU Z Q,DENG D H,SCHUTTER G D,et al.Chemical sulfate attack performance of partially exposed cement and cement+fly ash paste research article[J].Construction and Building Materials,2012,28(1):230-237.
[9]SISOMPHON K,FRANKE L.Evaluation of calcium hydroxide contents in pozzolanic cement pastes by a chemical extraction method[J].Construction and Building Materials,2011,25(1):190-194.
[10]卢峰,金祖权,孙朋朋,等.混凝土粉末对硫酸根离子的固化能力[J].腐蚀与防护,2012,33(11):932-934.LU F,JIN Z Q,SUN P P,et al.Influnence of concrete powders on binding capacity of sulfate ions[J].Corrosion Science and Protection Technology,2012,33(11):932-934.(in Chinese)
[11]金祖权,陈惠苏,赵铁军,等.混凝土在硫酸盐冻融中的损伤与离子传输[J].建筑材料学报,2015,18(3):494-498.JIN Z Q,CHEN H S,ZHAO T J,et al.Damage and ion penetration in concrete subjected to sulfate frost[J].Journal of Building Materials,2015,18(3):494-498.(in Chinese)
[12]杨全兵.混凝土盐冻破坏机理(I)毛细管饱和度和结冰压[J].建筑材料学报,2007,10(5):522-527.YANG Q B.Mechanisms of deicer-frost scaling of concrete(I)-capillary-cptake degree of saturation and ice-formation pressure[J].Journal of Building Materials,2007,10(5):522-527.(in Chinese)
[13]马志鸣,赵铁军,李绍纯,等.海洋潮汐环境下混凝土硫酸盐侵蚀机理研究[J].海岸工程,2014,33(1):31-36.MA Z M,ZHAO T J,LI S C,et al.Study on mechanism of concrete sulfate erosion in ocean tidal environment[J].Coastal Engineering,2014,33(1):31-36.(in Chinese)
[14]何小芳,缪昌文,洪锦祥,等.水泥浆体的热分析动力学[J].东南大学学报(自然科学学版),2011,41(3):601-605.HE X F,MIAO C W,HONG J X,et al.Thermal analysis kinetics of cement paste[J].Journal of Southeast University(Natural Science),2011,41(3):601-605.(in Chinese)
[15]颜哩哩,周文,尤迁,等.基于DSC-TG的钙矾石半定量分析方法[J].新型建筑材料,2015,42(2):41-43.YAN L L,ZHOU W,YOU Q,et al.Semi quantifying ettringite by DSC-TG method[J].New Building Material,2015,42(2):41-43.(in Chinese)