Search

The study aims to identify flexural behavior of RC beams strengthened using three different fiber‐reinforced polymers (FRPs) with differential cross‐sections configuration (i.e., middle and support sections). The experimental and calculations results of strengthening methods for RC beams were investigated utilizing FRPs under flexural loading. The strengthening FRP materials (CFRP, AFRP, and GFRP) were externally attached to the surface of the samples with U‐wrapped shape at the three different regions of the beams. The experimental results were compared with the fiber polymer systems of the American Concrete Institute according to the ACI 440.2R‐08 standards. The results demonstrated that RC‐9 specimen reinforced using AFRP exhibited higher load capacity performance than the others. The RC beams strengthened at both middle and support area exhibited more ductile behavior, which depends on the failure mode. Less crack formation was seen in the RC‐10 beams reinforced with AFRP, both in the middle and in the support area, compared with reference sample. The experiment revealed that FRP U‐jackets could be a promotive alternative to improve structural performance greatly and provide reliable and suitable solutions for sustainable buildings. [ABSTRACT FROM AUTHOR]

This study investigates structural behaviors of reinforced concrete (RC) moment frame connections strengthened using three different FRPs with different cross section configurations. The novelty of this research is the strengthening of a beam–column connection with FRP composites, where the joint consists of a weak column and a strong one that plays a vital role in the RC element. It is also rare in engineering to use inorganic composites in retrofit configurations (X shape, U shape, and T shape retrofit configurations). That is why we aimed to apply fiber-reinforced composite materials in different configurations (cross, diagonal, and parallel configurations). The experimental performance of strengthened samples was investigated using carbon fiber-reinforced polymer (CFRP), aramid fiber-reinforced polymer (AFRP), and glass fiber-reinforced polymer (GFRP) under loading systems. The strengthened RC specimens (SBWC-2—SBWC-7) were compared with a control specimen (SBWC-1) in terms of load capacity, ductility index, failure modes, and crack patterns. The strengthening of the SBWC-2 and SBWC-3 specimens using CFRP increased the ultimate loads up to 12.5% and 11.4% compared to reference sample, respectively. The first cracks in SBWC-4 and SBWC-5 beam–column joint specimens were found at loads of 35.4 kN and 33.8 kN, respectively. The results indicate that SBWC-2 specimen strengthened by AFRP displayed higher strength and ductile behavior than other specimens, as it depends on failure mode more than its counterparts. The reinforced X shape beam–column connection sample was protected from diagonal cracks. Strengthening with CFRP decreased visible-width shear cracks compared to control samples. The experiments revealed that CFRP composites could be a suitable alternative for greatly improving structural performance and providing suitable and reliable solutions for sustainable structures. [ABSTRACT FROM AUTHOR]