RETRACTED: Shear and flexural performance of low, normal and high-strength concrete beams reinforced with longitudinal SMA, GFRP and steel rebars

Abstract

Abstract Nowadays, developing the science of using modern materials plays a vital role to improve the structural behaviour of concrete members. This study aims to compare the influence of shape memory alloys (SMA), glass fibre reinforced polymer (GFRP) and steel longitudinal rebars on both flexural and shear performance of reinforced concrete (RC) beams produced by different concrete compressive strengths. Therefore, twenty-seven specimens with a cross-section of 150 mm wide, 200 mm high, and a length of 1500 mm, with different stirrup spacing and without transverse reinforcement, were manufactured and tested under four-point static load. Additionally, three types of concrete strength, including low-strength concrete (LSC), normal-strength concrete (NSC) and high-strength concrete (HSC) were employed to produce specimens. In these tests, the flexural capacity, displacement at the mid-span of the specimens, shear resistance, the maximum strain of concrete and ductility of specimens were evaluated. Additionally, some relationships were developed to show the approximate relationship between ductility and the flexural capability of RC beams based on the type of longitudinal rebars. Moreover, both shear and flexural experimental outcomes were compared with those obtained numerically according to the requirements of standards. The obtained results indicated that using GFRP and SMA rebars prevents the rapid reduction in the bearing capacity after the maximum load point. Also, GFRP and SMA rebars improve both maximum bending capacity and the deformation of specimens; however, the impact of SMA is higher than those manufactured with GFRP.