Produção e análise de compósitos epóxi e fibras vegetais para reforço à flexão em vigas de concreto armado

Abstract

The present study aims to analyze the production and application of vegetable fibers reinforced polymers (VegFRP) to the reinforcement of reinforced concrete structures. It has been produced composites with contents of about 50% 60% and 70% in fiber volumes. The composites tensile mechanical properties have been determined to evaluate the fiber content and arrangement with the best mechanical performance. Epoxy matrix and ramie and sisal vegetable fibers have been adopted in the production of VegFRP and their performance has been compared to epoxy matrix composites reinforced with carbon fibers (CFRP). The experimental program had been constituted by two phases, the first one in which VegFRP have been produced and characterized. In the second phase, vegetable reinforcements have been produced and applied in reinforced concrete beams, which have been subjected to threepoint flex testing. The reinforcements have been anchored to the beams in two forms, glued to the concrete surface and in notches on the covering layer. In parallel to the experimental program it has been performed numerical simulations using the finite elements method to dimension the reinforcements in the beams and simulate applications different from the experimental ones. The obtained results have showed that VegFRP have presented similar performance to the composites with carbon fiber applied as bending reinforcement of reinforced concrete beams. The load increase up to 76% to the ramie VegFRP anchored by the bonding technique of reinforcement on the concrete surface.