冻融循环和碳化交替作用下的混凝土耐久性  

Study of concrete durability under alternative effect of carbonation and freeze-thaw cycles

作　　者：赵高升[1] 何真[1] 杨华美[1] 

机构地区：[1]武汉大学水资源与水电工程科学国家重点实验室,湖北武汉430072

出　　处：《武汉大学学报（工学版）》2013年第5期604-609,共6页Engineering Journal of Wuhan University

基　　金：国家重点基础研究发展计划项目-973计划(编号:2013CB035901);国家重点基础研究发展计划项目-973计划(编号:2009CB623201);长江水利委员会长江科学院开放基金(编号:CKWV2012309/KY)

摘　　要：采用单边冻融和一维碳化的方法,在冻融循环和碳化交替作用下,研究混凝土耐久性能的演变规律及其与气孔结构变化的关系.结果表明,在交替作用早期,碳化能够阻止部分冻融产生的气孔结构衰变,但随着交替作用周期的延长,碳化不断消耗孔壁周围的钙电子层,破坏气孔体系的稳定.在交替作用早期,碳化有利于提高混凝土的抗冻耐久性,但到后期,碳化反而加速混凝土的冻融破坏.在实际工程中进行混凝土结构抗冻耐久性设计和使用寿命预测时,必须考虑和引进碳化与冻融的交替作用.By single side freezing and thawing and one-dimensional carbonation, the evolution of concrete durability and pore structure were investigated under exposure of freeze-thaw cycles and carbonation in turn. Results show that carbonation can prevent part of degradation of pore structure caused by process of freezing and thawing in the early cycles. But the pores structure stability was destroyed due to consump- tion of calcium electronic shell on the pore walls by carbonation as the increment of alternative cycle. Therefore, carbonation can improve the freeze -thaw durability of concrete in the early cycles; but it＇s pre- cisely the opposite in the later period. The alternative effect of freeze-thaw cycles and carbonation should be taken into account as respect to freeze -thaw durability design and service life prediction of concrete structure in practical engineering.

关 键 词：冻融循环 碳化 交替作用 气孔结构 耐久性 

分 类 号：TV431[水利工程—水工结构工程]