6 - Strengthening of reinforced concrete (RC) columns with fibre-reinforced polymer (FRP) composites

Abstract

Listen

Translate article

Publisher Summary An important application of Fiber-Reinforced Polymer (FRP) composites is to provide confinement to Reinforced Concrete (RC) columns to enhance their load-carrying capacity and ductility. This method of strengthening is based on the phenomenon that the axial compressive strength and ultimate axial compressive strain of concrete can be significantly increased through lateral confinement. Various methods have been used to achieve confinement to columns using FRP composites. In situ FRP wrapping has been the most commonly used technique, in which unidirectional fiber sheets or woven fabric sheets are impregnated with polymeric resins and wrapped around columns in a wet lay-up process, with the main fibers orientated in the hoop direction. In addition, filament winding and prefabricated FRP jackets have also been used. The filament winding technique uses continuous fiber strands instead of sheets/straps, so that winding can be achieved automatically by the means of a computer-controlled winding machine. When prefabricated FRP jackets are used, the jackets are fabricated in half-circles or half rectangles and circles with a slit or in continuous rolls, so that they can be opened up and placed around columns.