Contribuição ao entendimento do fenômeno do transporte de umidade na alvenaria de blocos de cerâmicas assentada com argamassa cimentícia.

Abstract

In Brazil, buildings use ceramic bricks and Portland cement mortar as constituent materials for the walls of buildings, which act as coatings and delimiting elements for internal areas. These materials are porous and highly susceptible to degradation due to the presence of moisture. Water penetrates structures through pores and compromises the useful life of buildings if not identified and treated early. The region between one layer and another of a wall is called the interface, and due to the presence of this region, the moisture transport in multilayer elements differs from those found in monolithic elements. The change in moisture transport behavior is proportional to the change in the nature of the contact and the water properties of the interface, and is called the Interface Resistance. The research discusses the behavior of moisture transport in specimens composed of ceramic brick and cementitious mortar, with different contact configurations, mortar traces and base dimensions. We sought to understand how these factors influence the cumulative moisture flow, the moisture content of porous materials and the water resistance of the interface. An extensive experimental program was developed with tests on 180 specimens. Three mixes of mortar, in mass, using CP V cement, hydrated lime, washed sand and distilled water were prepared: 1:2:9, 1:1:6 and 1:0.5:4. The specimens had a square base with sides measuring 5 cm, 7 cm and 10 cm. The research investigated hydraulic and perfect contact. For each contact configuration, 90 specimens were made, 30 for each mortar mix. Different performances were observed for specimens of different traits, where some absorbed less water than others. When comparing the different areas of the bases of the specimens for each mix, in all cases the absorption (moisture content) of water increases when the area is increased. The calculation of the water resistance was carried out by two different methodologies, with an important difference between them in the final result, even though they were in the same order of magnitude.