Análisis comparativo de la flexión simple y compuesta entre vigas de concreto reforzadas con: acero y polímeros reforzados con fibra de vidrio

Abstract

Abstract: Steel rebars are the main reinforcement material in structural elements, achieving a high adhesion when fused with concrete, forming an element resistant to compression, traction and shear. However, corrosion of rebar causes deterioration of reinforced concrete structures, which leads to research into new reinforcement technologies that extend the useful life of structural elements. Glass fiber reinforced polymer rods (GFRP) emerge as an alternative material to replace steel as reinforcement for structural elements. The objective of this project is to study the flexural behavior, ultimate load capacity, failure modes and crack patterns of structural elements (single and double reinforced beams with steel and GFRP). A total of 8 beams, with the following dimensions 150 mm x150 mm x600 mm, were prepared and tested in three-point bending following the provisions of ASTM C293. The behavior of three beams simply reinforced with steel (𝐴𝑠 = 2.534 𝑐𝑚2 ) versus one beam simply reinforced with GFRP (𝐴𝑓 = 1.571 𝑐𝑚2 ) is compared, as well as the behavior of three beams doubly reinforced with steel (𝐴𝑠 = 2.836 𝑐𝑚2 ) versus one beam simply reinforced with GFRP and steel (hybrid reinforcement) (𝐴𝑓 = 1.540 𝑐𝑚2 ). The single and double GFRP-strengthened beams have higher flexural strength as a function of ultimate load capacity considering that they are working with a lower cross-sectional area recommended by the GFRP bar suppliers. The single and double GFRP reinforced beams failed in shear while the steel reinforced beams experienced ductile failure and flexural cracking. GFRP bars can be considered as the best alternative reinforcement to replace steel because it has better mechanical and physical properties than steel bars.