摘要
目的研究圆形截面混凝土构件中自由氯离子含量分布的预测方法和含量分布规律,为混凝土结构的耐久寿命评估提供可靠的方法,为基于耐久性的结构设计提供理论依据.方法基于导出的氯离子在圆形截面混凝土中的扩散传质方程,结合算例,用有限差分法求解方程,研究自由氯离子含量分布规律.结果对于小尺寸圆形截面构件,计算结果与基于Fick定律的一维扩散方程预测值有显著差异.圆形截面钢筋混凝土构件的耐久寿命与保护层厚度同截面半径的比值有关.结论得出了各种因素对自由氯离子含量分布的影响规律,基于Fick定律的一维扩散方程应用于小尺寸圆形截面时有较大误差,圆形截面构件钢筋锈蚀开始时间受截面曲边效应的影响.
The rules of free chloride mass concentration distributing in circular section concrete element were studied in order to provide a reliable method and theoretical guidance for evaluating the service life and the structural design based on durability of reinforcement concrete （RC） structure. Combining with cases, the deduced equation was solved by the use of the finite difference method and their results were analyzed. The error was remarkable between the one dimension Fiek diffusion equation and the equation presented when it involved circular section RC structure of little size. And the rules of factors affecting on the chloride concentration distributing in circular section concrete element were obtained. The influence of the section＇ s property on the service life of circular section concrete element whose radius was shorter than 800mm should be considered.
出处
《沈阳建筑大学学报（自然科学版）》
EI
CAS
2006年第6期890-894,共5页
Journal of Shenyang Jianzhu University：Natural Science
基金
国家自然科学基金资助项目(50178003)
关键词
混凝土
耐久性
氯离子
扩散方程
concrete
durability
chloride
diffusion equation
