Estudo de matriz cimentícia reforçada com fibra têxtil para uso em painéis

Abstract

Textile reinforced concrete (TRC) is a cementitious matrix with the addition of long oriented fibers produced with multifilament. This composite is able of producing slender elements with reduced thickness, and important mechanical properties of high durability. The present work aims to evaluate in an experimental way the characteristics of two alkali resistant (AR) glass textiles with different mesh openings, as well as the influence on the mechanical properties when used as reinforcement with different amounts of layers in a cementitious matrix, in order to obtain efficiency parameters to be considered in two analytical structural design models. The experimental program was developed in stages, and in the initial, the textiles were characterized in terms of geometry with the aid of a digital microscope and tensile strength, in the isolated yarn and the fabric, for both orientations, weft and warp. The compressive strength and young’s modulus of the cement matrix were determined at the ages of 7, 28 and 91 days. In the next stage, were molded TRC specimens to characterize the tensile and flexural strength. Were produced containing one and two layers for the AR122 textile and specimens of one to four layers with the AR192 textile, with the textiles positioned in the two orientations. The results obtained were satisfactory from two layers, as they characterized the desired properties of textile reinforced concrete. Step three, based on the previous results, were molded panels with dimensions of 500 x 1000 mm, containing two and three layers of the AR192 textile, with thickness of 20 and 30 mm, in order to determine the flexural strength, only the textile AR 192 was used, because it demonstrated superior mechanical resistance in relation to the AR122 textile. Finally, in the last step, based on the results of the previous steps, it was possible to obtain the efficiency coefficients k1 and FPI, as subsidies for analytical design procedures. The theoretical results demonstrated satisfactory behavior and consistent with the experimental results, making it possible to insert the coefficients for design panel elements.