Análise da resistência à compressão de concreto com fibra de liga com memória de forma.

Abstract

Since concrete is one of the building materials most used in civil construction, it is necessary to carry out further studies aimed at improving its basic resistance properties, mainly through additions of other materials that can contribute significantly to its construction. use, such as fibers and chemical additives. With this in view, the following study intends to analyze the compressive strength of concrete specimens with the addition of shape memory alloys and their feasibility of use in civil works. Where were made the proper analysis of the properties of each component of the concrete. The phase transformation temperatures were determined, the stress x strain curve and the chemical composition of the shape memory alloy were determined. Due to the shape recovery property of this alloy when subjected to its shape recovery temperature ("activation"), it was used as reinforcement for the concrete in two distinct ways, the first being simply cut to the desired size and added to the mass of concrete and the second, being previously deformed and added in the mass, so that after the curing is heated above the "activation" temperature and generate a pretension inside the specimen. The results of the uniaxial compression strength of these specimens and of a control model without the alloy were obtained. It was possible to verify that the bodies with the activated wires had resistance above the ones with non activated wires, in which the functionality of the activation of the wires in the specimens was noticed. But when compared to the test specimens of the control, they had a lower resistance, but with very different models of rupture. Where those with activated wires could still withstand high loads even after their breakage due to their recovery from alloy form.