Experimental and numerical study of circular columns reinforced with steel and glass FRP bars

Abstract

Fibre-reinforced polymer (FRP) bars are important replacements for reinforcements made of ordinary steel because the former offer structural durability, electromagnetic neutrality and a high strength/weight ratio, as well as being lightweight and flexible. In the present study, six concrete columns with a diameter of 29·7 cm, a height of 1·5 m but with different percentages of steel and glass FRP bars were tested for endurance under a combination of an axial load and a reversed cyclic bending load up to failure. The experimental and numerical results in terms of force–displacement hysteresis are presented and discussed in this paper. Theoretical analysis was devoted to the refined modelling of the complex hysteretic response of experimentally tested columns with ordinary and composite reinforcement. Finite-element models of the specimens were formulated using a modelling concept of refined fibre sections.

Numerical investigation of GFRP bars contribution on performance of concrete structural elements

“…On the other hand, a study carried out by Afifi et al [18], [19] attributed lower ultimate compressive strength to GFRP rebars (approximately 35% of their ultimate tensile strength) than that measured by Deitz et al [17]. Due to the relatively low elastic modulus of GFRP bars, they are required to be well confined with stirrups in order to safely sustain some buckling [20]. This fact was also confirmed by the results of investigations attributing low ultimate capacity, low ductility, and brittle failure mode to columns with large tie spacing [21], [22].…”