钢筋地聚物涂层的耐腐蚀性能研究

Corrosion resistance of geopolymer coating of reinforcement

为研究建筑钢筋的地聚物涂层在不同氯离子浓度下的耐腐蚀性能。以偏高岭土、硅酸盐水泥等为原料制备地聚物涂料,将其均匀涂覆于钢筋,对仅涂覆一遍地聚物涂层的建筑钢筋试件依据Fick第二定律分析氯离子扩散的浓度、系数及时间。结果表明:随氯离子浓度从30%升到90%过程中,试件的锈蚀增加、电通量增大,但整体数值较小。随氯离子浓度的增长,钢筋试件的拉伸强度、断裂伸长率等均下降。地聚物涂层试件吸水率大幅减小,最终减小到约为0.2%。当氯离子浓度达到100%时,地聚物涂层试件的质量损失率约为0.1%,且质量损失率速率较慢。

In order to study the corrosion resistance of geopolymer coatings on building steel bars under different chloride ion concentrations,the geopolymer coating was prepared with metakaolin,portland cement,etc.As raw materials,and coated on the reinforcement.For the building reinforcement specimens with only one layer of geopolymer coating,the concentration,coefficient and time of chloride ion diffusion were analyzed according to the second law of Fick.The results show that with the increase of chloride concentration from 30%to 90%,the corrosion and electric flux of the specimen increase,but the overall value is small.As the concentration of chloride ions increases,the tensile strength and elongation of the steel bar specimens decrease.The water absorption rate of the geopolymer coated specimen decreases significantly,ultimately decreasing to about 0.2%.When the chloride ion concentration reaches 100%,the mass loss rate of the geopolymer coated specimen is about 0.1%,and the rate of mass loss is relatively slow.