Influence of stress damage and high temperature on the freeze–thaw resistance of concrete with fly ash as fine aggregate

• Published in: Construction & building materials Vol. 229; p. 116845
• Main Authors: Zhang, Dongsheng, Mao, Mingjie, Zhang, Shangrong, Yang, Qiuning
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 30.12.2019
• Subjects: Concrete with fly ash as fine aggregate; Coupling action; Freeze–thaw; High temperature; Stress damage; Freeze–thaw; High temperature; Concrete with fly ash as fine aggregate; Stress damage; Coupling action
• ISSN: 0950-0618; 1879-0526
• DOI: 10.1016/j.conbuildmat.2019.116845

•Both experimental and microstructural analysis techniques were employed.•Initial stress damage accelerates the freeze–thaw damage of concrete.•Stress damage and high temperature affect freeze–thaw resistance of concrete.•Replacing fine aggregate with fly ash can improve freeze–thaw resistance of concrete. A multifactor coupling test protocol was designed to determine the freeze–thaw resistance of concrete with fly ash as fine aggregate (CFA). Rapid freeze–thaw tests were conducted to measure the mass loss and relative dynamic modulus of elasticity of concrete specimens to evaluate their freeze–thaw resistance. The test results show that the freeze–thaw resistance of the concrete decreases with the increase in the initial stress damage. The coupling effect of stress damage and high temperature accelerates the attenuation of mass and relative dynamic modulus of elasticity of concrete. CFA has a higher freeze–thaw resistance than concrete.