摘要
通过分析混凝土中各原材料的氯离子含量,研究了不同氯离子含量的砂样和水样、不同养护龄期以及不同强度等级对新拌混凝土及硬化混凝土中氯离子总量的影响。结果表明:随着砂、水中氯离子含量的增加,混凝土拌合物及硬化混凝土中氯离子含量显著增加;混凝土硬化后随着龄期的增长,其氯离子含量呈下降趋势;当砂中氯离子含量超出规定时,混凝土中的氯离子总量容易超标,即使混凝土其他原材料氯离子含量都达标,硬化后的氯离子含量也仍可能超标;随着混凝土强度等级的提高,混凝土中的氯离子总量明显降低;各原材料的氯离子含量计算总量接近且略高于新拌混凝土实测氯离子含量,可采用计算混凝土各原材料中氯离子含量的方法预测硬化混凝土中氯离子总量是否超标。
Through the analysis of the Cl-content of various raw materials in concrete,the impact of sand samples and water samples with different Cl-content and different curing ages,different strength grades on the total Cl-content in concrete mixtures of and hardened concrete were studied.The results show that as the Cl-content in sand or water increases,the Cl-content in the concrete mixture and hardened concrete increases significantly.After hardening,as the curing age increases,the Cl-content of the concrete shows a downward trend.When the Cl-content in the sand exceeds the standards,the Cl-content in the concrete easily exceeds the target.Even if the Cl-content of each raw material of concrete meets the standard,the Cl-content of the concrete may still exceed the standard after hardening.With the improvement of concrete design strength grade,the Cl-content in the concrete decreases significantly.The calculated values of total Cl-content of each raw material is close to and slightly higher than the test values of chloride ion content of fresh concrete.The method of calculating the total amount of Cl-in each raw material of concrete can be used to determine whether the Cl-content in hardened concrete exceeds the standard.
作者
张琨健
ZHANG Kun-jian(Fujian Academy of Building Research Co.,Ltd.,Fuzhou 350025,China;Fujian Provincial Key Laboratory of Green Building Technology,Fuzhou 350025,China)
出处
《混凝土与水泥制品》
2021年第12期24-28,共5页
China Concrete and Cement Products
关键词
氯离子含量
混凝土
原材料
耐久性
强度等级
养护
Chloride ion content
Concrete
Raw material
Durability
Strength grade
Curing
