Effects of Freeze-Thaw Cycle on the Mechanical Properties of Early-Age Mortar

Abstract

Cement mortar subjected to freeze-thaw cycle action at an early age is expected to suffer serious physical damage, resulting in the cement mortar’s mechanical performance degradation. In this study, we examine the effects of rapidly repeated freeze-thaw cycles on 81 moulded cement mortar specimens of different mixed proportions at an early age by using destructive and non-destructive testing methods. Three mortar mixes with different water-cement ratios of 50%, 60%, and 70% were tested to compare the mechanical properties according to JIS R 5201. The test findings demonstrate that the 50% water-cement ratio of mix composition is highly advised due to its improved early-age strength following the freeze-thaw process. The freeze-thaw test against mortars also indicates a strong link between mix proportions, curing age, and frost durability. Furthermore, ultrasonic pulse velocity showed a high correlation with compressive strength for specimens not subjected to freeze-thaw cycle action. These highlights could provide a laboratory reference of theoretical values for early-age cement mortar on its mechanical properties and can also be applied to extend the strength-weakness theory of cement mortars subjected to freeze-thaw cycles.