不同养护制度下粉煤灰混凝土压缩冻融损伤演化
Evolution of Compression Freeze-thaw Damage of Fly Ash Concrete Under Different Curing Systems
莫黎 1魏留明 1周强 2于雷3
作者信息
- 1. 河南建筑职业技术学院工程管理系,河南 郑州 450064
- 2. 中国港湾工程有限责任公司,北京 100027
- 3. 武汉理工大学硅酸盐建筑材料国家重点实验室,湖北 武汉 430070
- 折叠
摘要
为研究不同养护制度下混凝土冻损受压损伤演化规律,开展粉煤灰混凝土冻融循环试验和单轴压缩—声发射试验.结果表明,蒸养混凝土冻损受压行为呈明显"三阶段"分布特征,即瞬时变形期(Ⅰ阶段)、变形发展期(Ⅱ阶段)及变形陡增期(Ⅲ阶段);随着冻融循环次数的递增,变形发展期与变形陡增期的分界点在时间横轴上后移,累计事件数峰值呈先增后减变化趋势;蒸汽养护温度过高对混凝土抗冻性不利.
Abstract
To study the evolution law of concrete freeze-thaw compression damage under different curing systems,freeze-thaw cycle tests and uniaxial compression-acoustic emission tests for steam cured concrete were conducted.The re-sults indicate that the compressive failure process of freeze-damaged steam cured concrete can be divided into three stages:instantaneous deformation period(Phase Ⅰ),deformation development period(Phase Ⅱ),and deformation steep in-crease period(Phase Ⅲ).As the number of freeze-thaw cycles increases,the boundary point between the deformation de-velopment period and the deformation steep increase period shifts backward on the horizontal axis of time,and the peak cumulative event number shows a trend of increasing first and then decreasing.Excessive steam curing temperature is detrimental to the frost resistance of concrete.
关键词
养护制度/粉煤灰混凝土/冻融循环/冻损受压/损伤度/声发射Key words
curing system/fly ash concrete/freeze-thaw cycle/freeze damage and compression/degree of damage/acoustic emission引用本文复制引用
基金项目
国家自然科学基金项目(52108170)
2023河南省社科联项目(SKL-2023-133)
出版年
2024
NETL
NSTL
万方数据