Applications, properties, and influence of the curing in stabilized mortars supplied in Concórdia - SC

Abstract

Brazilian standards that standardize the execution, application and technological control of stabilized mortars have not yet been developed, with only guidelines and care provided by the manufacturers. In addition, there is concern about the application of stabilized mortar on facades due to exposure, once the system is subject to static and dynamic environmental pressures that contribute to the opening of cracks, facilitating the entry of water and aggressive agents. Within this context, this work aimed to evaluate stabilized mortars supplied in the city of Concordia, SC. For this, it began with a questionnaire to workers who apply the mortar on site. Then, the properties in the fresh and hardened state of the mortars were analyzed in the laboratory. Finally, a comparison of curing execution in hardened mortar was performed. The results showed that the two mortars under study had high water retention, which may have influenced the low tensile bond strength of mortar B. Furthermore, water spray curing also reduced the tensile bond strength at 28 days of the two mortars under study. Furthermore, submerged curing increased the compressive strength and tensile strength in the flexion of mortar A, however, there was a reduction in these properties for mortar B. Regarding the applications and procedures performed by companies participating in the research, the results showed that mortars with stabilization time of 36 and 48 hours are the most used, since most applications are for laying, internal and external coating of masonry, and that 92% of the companies do not made cure on mortars. Thus, it could be concluded that there is no performance standard for the mortars of the two supplying companies in the city, demonstrating the importance of developing specific standards for stabilized mortars. In addition, the reduction in the physical properties of the samples in which curing was performed may demonstrate a dosage strategy, by the companies, which foresees the non-performing of curing at the construction site.