Estudo da fibra natural do capim annoni como elemento de reforço em matriz cimentícia

Abstract

This work aims study the capim annoni fiber as a reinforcing element in cementitious matrix. Tensile tests were performed for the mechanical characterization the fiber, and pullout fiber tests, for evaluating fiber in the cementitious matrix. The tensile strength was evaluated for three fiber lengths 15, 30 and 50 mm and each them at different speeds: 0,5 mm/min, 1 mm/min, 5 mm/min and 10 mm/min. The best tensile results were found for the speed of 5 mm/min, for both the 30 mm and 50 mm fiber length the break voltage values fall between 14,44 and 158,67 MPa, results similar to coconut fiber, and the modulus of elasticity between 1,41 and 10,24 GPa, values close to the fiber Sisal, Coco and Palmyra. The pullout tests were performed at speed 0,05 mm/min for two fiber embedment lengths in the cementitious matrix, 25 mm and 50 mm. For pullout testing with a length of 25 mm embedment fiber was predominantly the frictional tension, and length 50 mm was the predominant adesional tension, shear stress values were between 0,0012 and 0,0461 MPa, do not occurring fiber breakage, but a detachment of the same from the interior of the matrix. Based on the results obtained and comparing them with the literature, it was not possible to determine the best embedment for fiber, for better grip fiber-matrix due to sliding of the fiber.