Estudo sobre os efeitos do aumento da temperatura ambiente durante a cura da argamassa

• Autor(a) principal: Pires, Rafaela Pereira
• Data de Publicação: 2020
• Tipo de documento: Trabalho de conclusão de curso
• Idioma: por
• Título da fonte: Repositório Universitário da Ânima (RUNA)
• Texto Completo: https://repositorio.animaeducacao.com.br/handle/ANIMA/4546
• topic: Resistência mecânica; Tempo de pega; Temperatura

Over the years, we have seen the population increase and the appearance of several buildings, new skyscrapers and buildings with varied architectures, ranging from simpler construction patterns to the most elaborate architectural projects. Therefore, greater care must be taken with the construction stages, seeking to ensure the safety and stability of these new buildings. When it comes to safety, the creation and updating of technical standards are intended to meet quality standards and guarantee users the best cost-benefit ratio, preserving the construction criteria, from the raw material in the initial stages, to finishing and delivery of these. Some standards address the parameters in order to obtain the best resistance and cure of mortars. The latter in turn can receive influences of the most diverse, from the temperature fluctuation in the preparation of the material to the ambient temperature when it is used in civil construction. Following this reasoning, the research has as main objective to examine the effect of temperature on the mortar curing and its mechanical resistance at the end of the curing period. Another factor investigated will be the time of catching this material subject to certain temperature variations. This work has an experimental character, where several mortar samples were produced which were submitted to temperature variations. Under these variations, the behavior of the mechanical resistance and the setting times were monitored, the samples cured in a thermal tank at temperatures of 20ºC, 30ºC, 40º and 50ºC were evaluated. From the results obtained, it was observed that the mortars showed better resistance in the samples submitted to temperatures between 30º C and 40ºC, where they acquire an increase of the mechanical resistance of 17.7% and 18.6% respectively in relation to the standard sample of 20ºC for the 28 days of healing. The samples submitted to temperatures of 50ºC suffered a small reduction of mechanical resistance of 1.8% in relation to the standard sample, but are close to the requested resistance of 25 MPa. Regarding the setting time, there was a reduction in the start and end times. The samples analyzed at 40º C and 50ºC showed a reduction of 36.36% in the variation of the setting time, which demonstrates that the internal reactions of the cement are accelerated with the increase of the ambient temperature, causing that there is not a complete filling of the matrix, generating pores and consequently reducing the mechanical resistance, as observed.