陶瓷粉再生混凝土氯离子扩散性能研究

(1. 南昌铁路勘测设计院有限责任公司,江西 南昌330002; 2. 华东交通大学 土木建筑学院,江西 南昌 330013)

陶瓷粉; 氯离子; 水胶比; 扩散系数; 耐久性

Study on chloride diffusion properties of reclaimed concrete from ceramic powder
PENG Yuehui1, HUANG Linya2, CHEN Mengcheng2, YUAN Mingsheng2

(1.Nanchang Railway Survey and Design Institute Co. Ltd. Nanchang 330002, China;2.School of Civil Architecture, East China Jiaotong University, Nanchang 330013, China)

ceramic powder; chloride ion; water-to-binder ratio; diffusion coefficient; durability

DOI: 10.15986j.1006-7930.2019.02.004

备注

针对自由氯离子在陶瓷粉再生混凝土中的扩散性能研究,试验采用自然浸泡法,探究了不同水胶比、陶瓷粉取代量以及浸泡时间三种因素对混凝土中氯离子扩散规律的影响.基于实测数据,通过研究不同陶瓷粉取代量对混凝土抗压强度的影响,以及自由氯离子浓度分布和扩散系数规律,并且对混凝土微观形貌进行分析.结果表明:混凝土的抗压强度随着陶瓷粉取代量的增大而降低; 陶瓷粉混凝土的氯离子扩散系数随着浸泡时间的延长而减小,随着水胶比的增大而增大; 混凝土中掺入陶瓷粉替代部分水泥能够提高混凝土的抗氯离子侵蚀性能,保护钢筋不易受到腐蚀,有效延长结构的使用寿命.掺入的陶瓷粉量在20%左右时能得到最佳效果.

In order to study the diffusion properties of free chloride ions in ceramic powder recycled concrete, the natural immersion method was used to investigate the effects of different water-to-binder ratios, ceramic powder substitution and soaking time on the diffusion of chloride ions in concrete. Based on the measured data, the effects of different ceramic powder substitutions on the compressive strength of concrete, the distribution of free chloride ion concentration and the law of diffusion coefficient were studied, and the microstructure of concrete was analyzed. The results show that the compressive strength of concrete decreases with the increase of ceramic powder substitution; the chloride ion diffusion coefficient of ceramic powder concrete decreases with the immersion time, and increases with the increase of water-to-binder ratio; The inclusion of ceramic powder in the concrete instead of part of the cement can improve the chloride ion corrosion resistance of the concrete, protect the steel bar from corrosion, and effectively extend the service life of the structure. The best effect is obtained when the amount of ceramic powder incorporated is about 20%.