Confinement strengthening of heat-damaged reinforced concrete columns Available to Purchase

The effectiveness of different strengthening techniques in restoring heat-damaged concrete short columns was evaluated experimentally. Four confinement strengthening systems were employed: high-strength fibre-reinforced concrete (HSFRC), ferrocement (FC), glass-fibre-reinforced polymer (GFRP) and steel plate (SP) jacketing. Fifty-one reinforced concrete prisms of size 150 × 150 × 450 mm were first subjected to different elevated temperatures. Heated specimens were strengthened using one of the chosen techniques. Thereafter, all specimens were tested under monotonic loading to determine the axial ultimate strength, stiffness, ductility, energy absorption and peak stress–strain behaviour. It was observed that the GFRP jacketing was effective in restoring the compressive strength and energy dissipation, but was not capable of restoring the stiffness. However, FC and HSFRC jacketing were effective mainly in restoring the stiffness of heat-damaged concrete. SP jacketing was not effective in improving the strength or the stiffness properties. GFRP jacketing was found to be the most effective method for strengthening of fire- or heat-damaged concrete structures.