摘要
对浸泡在0.44%和5.00%硫酸钠溶液中水灰比为0.24、0.28和0.32的硬化水泥浆体不同龄期下的膨胀率、质量损失和抗压抗蚀系数等性能进行了研究,并采用差热分析仪(DSC)、X射线衍射仪(XRD)和扫描电镜(SEM)对侵蚀产物物相和微结构进行了分析。结果表明:水泥浆体出现由边角向内部逐层侵蚀,导致水泥试件膨胀、开裂和剥落;增加水灰比和环境中硫酸根离子浓度都会加速侵蚀破坏;在高浓度侵蚀环境下,劣化过程包含慢速破坏阶段和快速破坏阶段,石膏的大量形成是引起试件快速破坏的主要原因。
The expansion,mass loss and compressive corrosion resistance coefficient of hardened cement pastes,with water cement ratio of 0.24,0.28 and 0.32,soaked in 0.44%and 5.00%sodium sulfate solutions,were studied at different ages.The phases and microstructure of attacked specimens were analyzed by differential scanning calorimeter(DSC),X-Ray diffractometer(XRD)and scanning electron microscope(SEM).The results show that the cement paste specimens are attacked layer by layer from the corner to the inside,causing the expansion,cracking and spalling.The increase of water cement ratio and sulfate ion concentration in the environment can all accelerate the erosion damage.In the environment of high sulfate concentration,the deterioration process includes slow and fast failure stages,and the formation of a large number of gypsum is the main reason for the rapid failure of specimens.
作者
王金川
陈登
WANG Jin-chuan;CHEN Deng(Hainan Construction Engineering Co.,Ltd.,Haikou 570102,China;College of Civil Engineering,Suzhou University of Science and Technology,Suzhou 215011,China)
出处
《混凝土与水泥制品》
2021年第7期21-25,共5页
China Concrete and Cement Products
基金
安徽省先进建筑材料工程实验室开放课题项目(JZCL006KF)。
关键词
硫酸盐侵蚀
硫酸钠
钙矾石
石膏
水泥浆体
Sulfate attack
Sodium sulfate
Ettringite
Gypsum
Cement paste
