Deformações e modo de ruptura em prismas de alvenaria de blocos cerâmicos: análise experimental com extensometria e correlação de imagem

Abstract

The main objective of this work is to analyze the stress-strain curve of masonry materials in prisms with two different hollow clay blocks and two mortars with different strengths, verifying the mechanical behavior of the prisms and the rupture mode of each typology when submitted to axial compression. This study used two clay block types, hollow face shell and solid face shell. The compressive strengths of the blocks are 9.85 MPa for the hollow face shell and 22.50 MPa for the solid face shell. The prisms were molded with mortar produced in the laboratory, made of cement, lime and sand, aiming to obtain a mortar with a fa/fbm,líq relationships = 0.30 and another with a fa/fbm,líq = 0.70. For this purpose, tests of resistance to axial compression were performed on instrumented prisms to analyze the behavior and specific axial deformation separately of each material in the set, in addition to being also filmed for the evaluation of the rupture mode and deformations through digital image correlation. Besides to the prisms, the ceramic blocks and mortars were also instrumented and filmed during the compressive strength tests individually in order to correlate them with the behavior together in the prisms. From the analysis of the results, the influence of the proportion that exists between the compressive strength of the mortar and the block on the strength and the rupture mode of the ceramic prisms was observed. It was found that the strength of the mortar did not have significant interference in the ultimate strength of the prisms, but in the triggering of the rupture mode process, which could accelerate or delay the start of the rupture process. The deformations of the components of the prisms recorded through the strain gauges and through the DIC technique showed differences, and it was found that the deformations recorded through the DIC technique more adequately represent the behavior of the evaluated typologies. In addition, it is concluded that the DIC technique becomes an appropriate mechanism for the evaluation of displacements and deformations for masonry.