Evaluación del acero estructural reforzado con fibra de carbono unidireccional mediante el método de ensayo a flexión de tres puntos, descrito en la normativa ASTM E290- 22 para determinar el incremento de resistencia

Abstract

The need for a method to rehabilitate a structural member has increased significantly due to the increase in magnitudes in live load. The reconditioning method using steel plate is not a viable solution due to the added weight, difficulty of fixing and welding problems, as well as being prone to corrosion and fatigue. Previous research, determined that there is a directly proportional relationship between roughness and adhesive strength, also developed alternative methods of surface cleaning, to improve adhesive bonds, because of this we proceeded to evaluate how the contact area influences depending on the flexural strength, obtaining results when applying the three-point bending test described in the ASTM E290-22 standard, In addition, the compressive properties of the adhesive were analyzed by means of a group of specimens dimensioned according to the ASTM D695 standard, however a mathematical model was implemented to establish differences between tests. With the present investigation we compared the results obtained from the behavior of structural steel ASTM A-36 reinforced with unidirectional carbon fiber adhered by a high strength thixotropic adhesive, in a three-dimensional format, in two groups of specimens, which one of them did not have reinforcement, evidencing the doubled increase in resistance, the group that presented the best results for not having failure due to detachment, was the one with the largest contact area with an average value of 10,646 micrometers and a maximum flexural effort of 893.05 MPa.