PROPERTIES VARIATION OF CONCRETE ATTACKED BY ACIDIC SOLUTIONS
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摘要: 根据酸雨的特点配制了5种具有不同pH值、不同硫酸根离子浓度的酸性溶液,研究了混凝土在干湿循环、酸性溶液侵蚀30d到150d强度的变化、表层混凝土的吸水性以及其孔结构的变化。经过含有硫酸盐溶液的侵蚀后,混凝土强度的变化经过一个先降后升、然后再降低的过程;而经过不含硫酸盐溶液的侵蚀后,混凝土的强度持续下降。受不含硫酸根离子的酸性溶液侵蚀后,表层混凝土的孔隙结构变化较大,孔隙率增加、孔径增大。硫酸盐侵蚀产物的形成过程与混凝土的宏观性能的变化密切相关。Abstract: Rapid development of industry caused increase of acidic medium concentration in environments,and the deterioration of concrete performance caused by acidic attack had been paid more attention.In the present paper,five acidic solutions with different pH,different SO_4~(2-) concentration were prepared to simulate acidic rains.The strength variation,sorptivity and pore structure of concrete were measured after acidic attack for 30-150 d,in a dry-wet regimen.Results showed that,after attack of acidic solutions with SO_4~(2-),the strength of concrete reduced at firstly,then increased and reduced at last.It is possible that the reaction products of cement hydrates in concrete with SO_4~(2-) governing property variation of acid attacked concrete.However,after attack of acidic solution without SO_4~(2-),the strength decreased continuously.The reason might be the quality degradation of pore structure after pure acidic attack.
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Key words:
- acidic medium /
- concrete /
- attack /
- sorptivity /
- pore structure
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洪乃丰.水环境腐蚀与混凝土的耐久性[J].腐蚀与防护,2006,27(4):174-177; [2] 刘泳珍.酸沉降的形成、危害及其防治.湘潭矿业学院学报,1994,9(1):21-24; [3] Regourd M.31-RCA:Resistance of Concrete to Chemical Attack[J].Material and Structures,1981,14:130-137; [4] 于忠,胡蔚儒.化工大气环境中混凝土的腐蚀机理及性能研究[J].混凝土,2000(8):10-15; [5] Kong L H,James G.Concrete Deterioration Due to Acid Precipitation[J].ACI Materials Journal,1987,84:110-116; [6] Attiogbe K,Rizkalla S H.Response of Concrete to Sulfuric Acid Attack[J].ACI Materials Journal,1988,85:481-488; [7] Chandra S.Hydrochloric Acid Attack on Cement Mortar-an analyticalStudy[J].Cement and Concrete Research.1988,18:193-203; [8] Fattuhi N I,Hughes B P.The Performance of Cement Paste andConcrete Subjected to Sulphuric Acid Attack[J].Cement and ConcreteResearch[J],1988,18:545-553; [9] Ceukelaire L D.The Effects of Hydrochloric Acid on Mortar[J].Cement and Concrete Research,1992,22:903-914; [10] Pavlik V.Corrosion of Hardened Cement Paste by Acetic and NitricAcids PartⅠ:Calculation of Corrosion Depth[J].Cement andConcrete Research,1994,24:551-562; [11] 申春妮,杨德斌,方祥位,等.混凝土硫酸盐侵蚀影响因素的探讨[J].水利与建筑工程学报,2004,2(2):16-19.
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