Avaliação das argamassas para encunhamento: aplicadas em parede de alvenaria

Abstract

Pathological manifestations in sealing masonry have been diagnosed early in the area of connection between the masonry and the structure, causing a major problem in civil construction, especially in the wedge region, so important and little explored in research. Thus, there is a need for a specific Brazilian standard for the execution and parameters of mortars for wedging. The objective of this work was to research, compare data and evaluate the effectiveness of wedge mortars, identifying the best flexible wedge mortar that is effective in minimizing pathological manifestations in the wedge region. And which mortar dampens the structural deformations that are transmitted to the masonry. To achieve the objective, compression tests were carried out on walls with five different wedge mortars. The deformations of the masonry and the wedge were evaluated, through laboratory tests of characterization and mechanical resistance of the mortars, in the fresh and hardened state, and the resistance of the mortars applied on walls. The tests in the fresh state were carried out to determine the consistency index, specific mass and air content. In the hardened state, the properties studied were water absorption, void ratio, specific mass, dynamic modulus of elasticity and mechanical compressive and tensile strengths in bending. And the wall shear and compression test, in order to determine the deformation and the shear strength of the mortars applied in the wedge region. For this specific study for the wedging region, it was limited to 4 mortars and polyurethane foam, being 3 resilient mortars and 1 rigid mortar. The results of the mortars show that the more resilient they are, with the modulus of elasticity and high incorporated air content, the more they absorb the tensions imposed on the wall and the occurrence of anomalies becomes later, according to the application of axial load in the sealing system. In the case of polyurethane foam, which is highly flexible, the anomalies appear early, with an applied load of 6 kN. On the other hand, the wall without wedge obtained the first anomaly evidenced at 61 kN and there was a rupture at 82.54 kN. While the industrialized mortar was the later, the first anomaly was evidenced at 137.20kN.