Behaviour of FRP Confined Concrete Cylinders: Experimental Investigation and Strength Model
The present paper is devoted to investigate the behaviour of FRP confined concrete cylinders subjected under axial compressive loading. A total of 54 FRP confined concrete cylinders with 2 types of FRP composite wrap, Carbone fiber reinforced polymer (CFRP) and glass fiber reinforced polymer (GFRP), were tested under monotonic axial compression. The effects of several parameters such as unconfined concrete strength, type of FRP composite and number of FRP layers are investigated. Three different concrete mixes were examined, with a compressive strengths average of 26, 40 and 60MPa. The effective circumferential FRP failure strain and the effect of the effective lateral confining pressure were investigated. Peak axial compressive strength and corresponding strain of unconfined and FRP confined concrete cylinders were compared. The obtained results show that the CFRP reinforced cylinders provide a significant increase in ultimate compression stress compared to the GFRP reinforced ones. A new model is presented to predict the compressive axial strength and corresponding strain of FRP confined columns.