Influence of GFRP rebars diameter on bond characteristics of reinforced cement concrete

Abstract

The bond strength of any reinforced concrete elements is important to enhance the structural strength and durability of the structures. In this present study, Glass Fibre Reinforced Plastic (GFRP) reinforcing bars have been introduced as reinforcement for concrete structures subjected to corrosive conditions or where electrical/electromagnetic insulation is required. In order to ascertain the bond behaviour, a beam bond strength test and pull-out test were conducted, in addition to the preliminary tests such as physical and mechanical properties (compressive strength, splitting tensile strength test, flexural strength test) of the specimens. Totally, four types such as GFRP, Thermo-Mechanically Treated steel (TMT), High yield strength deform (HYSD) and Mild steel (MS) of rebars were used with varying diameters of the bar. GFRP rebars showed higher bond stress values compared to HYSD and TMT steel rebars from the beam bond test. And TMT rebars showed higher bond stress values compared to HYSD rebars from both beam bond and pull-out tests.