摘要
为合理评价混凝土中发生硫铝酸盐膨胀反应的硫酸根离子浓度,应用电子探针显微分析技术,研究了碳化对水泥石中硫元素分布的影响,阐明了碳化作用下混凝土中硫元素的迁移规律.结果表明:碳化前水泥石截面的硫元素分布比较均匀,碳化后水泥石中的硫元素由碳化区向非碳化区迁移和积聚,硫元素在碳化区浓度较低,非碳化区浓度较高,钙矾石含量也随之增大,这种因碳化作用造成的硫元素分布不均匀可能导致混凝土局部发生硫铝酸盐膨胀开裂.
In order to evaluate the concentration of sulfate ion that would cause sulphoaluminate expansion in concrete,the influence of carbonation on sulfur distribution in hardened cement paste was investigated and the migration characteristic of sulfur under the carbonation was also clarified.The results show that the elemental sulfur distribution in hardened cement paste is relatively uniform before carbonation.However,sulfur element in carbonation area migrates and concentrates on the non-carbonation area in the process of carbonation,so the sulfur concentration deceases in carbonated zone and significantly increases in non-carbonated zone and the contents of ettringite.The uneven elemental sulfur distribution may cause local sulphoaluminate expansion of concrete.
出处
《建筑材料学报》
EI
CAS
CSCD
北大核心
2015年第3期477-481,共5页
Journal of Building Materials
基金
国家自然科学基金资助项目(51278255
51478227)
浙江省自然科学基金资助项目(LY12E08006)
宁波市重大科技计划项目(2013C51006)
关键词
水泥石
碳化
硫元素
迁移
积聚
hardened cement paste
carbonation
sulfur element
migration
concentration
