Influence of freezing test methods, composition and microstructure on frost durability assessment of clay roofing tiles

• Published in: Construction & building materials Vol. 25; no. 6; pp. 2888 - 2897
• Main Authors: Sánchez de Rojas, M.I., Marín, F.P., Frías, M., Valenzuela, E., Rodríguez, O.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.06.2011; Elsevier B.V
• Subjects: Cement; Clay (material); Clay minerals; Clay roofing tiles; Construction materials; Failure; Frost durability; Frost resistance; Lifetime; Mechanical properties; Microstructure; Porosity; Properties; Roofing; Roofing tiles; Tiles; Spain; Mechanical properties; Lifetime; Porosity; Microstructure; Frost durability; Clay roofing tiles
• ISSN: 0950-0618; 1879-0526
• DOI: 10.1016/j.conbuildmat.2010.12.041

► This paper compares the standard methods C and E (new) to predict the frost resistance of clay tiles. ► It deals with the effect of clay, microstructure and manufacturing on the frost durability. ► Microstructure was studied by DRX, FRX and mercury porosimetry. ► It leads on clay characterisation and industrial process control to improve frost durability. Clay roofing tiles are sensitive to frost action and require testing by repeated freezing and thawing cycles. The research purpose is to predict frost durability, taking into account the effect of clay mineralogy, microstructure (studied by DRX, FRX and mercury porosimetry) and manufacturing parameters, drawing an empirical comparison between methods C and E suggested by the European Standard. Method E is more severe and selective than method C, showing earlier failure and smaller dispersion, which may be explained due to the different saturation process, cooling kinetic and the presence of cloth. The damage increased with the number of cycles, it is substantially affected by the fired clay porosity and calcium content, being consistent with the thermodynamics and kinetics of the mechanisms that lead to failure. The findings provide guidance to improve frost durability based on clay characterisation and industrial process control.