Comportamento tensão-deformação de corpos de prova de argamassas de diferentes resistências submetidos a compressão axial

Abstract

The real behavior of the mortar in laying joints as the determination of its mechanical properties is difficult to reproduce in the laboratory, due to the confinement effects caused by the block and the changes resulting from the water exchange between blocks and mortar, which eventually results in little known knowledge of the subject. Thus, this work seeks to deepen the knowledge regarding the mechanical behavior of axially compressed mortar. For this, two different mortar traces (1:0.5:4 and 1:1:6), measured in volume of cement, lime and sand, and two different specimen heights (100 mm and 33 mm), with which compression tests were performed on strain gauges instrumented cylindrical specimens, in order to evaluate the influence of mortar strength and degree of confinement in relation to stress-strain behavior, modulus of elasticity and Poisson’s ratio. With the results achieved, it has been verified that the mortars with higher resistance presented superior deformation of the rupture and modulus of elasticity and that with the increase of the confinement there is a reduction of the modulus of elasticity. Poisson's coefficient showed different behavioural patterns according to the confinement conditions. In the case of less confined mortars, it remained constant with slight variations. In the most confined mortars, the variations were more pronounced from the critical stress level reached.