Bond performance of CFRP strengthened concrete subjected to fire

Abstract

CFRP (Carbon Fibre Reinforce Polymer) strengthening system has recently emerged as a practical alternative for the flexural strengthening of reinforced concrete structures because of its efficiency in terms of structural performances, costs, labour and time savings. While CFRP is widely used in bridge construction, it can also be taken advantage of for strengthening concrete members such as beams, columns and slabs. Even though structural engineers are interested in using CFRP for the strengthening work of concrete members in buildings, always hesitation occurs due to lack of knowledge of its fire performance. Therefore it is essential to assess and develop the needed information on fire resistance of CFRP strengthened concrete structural members. The epoxy adhesive used to create the bond is known to be very sensitive totemperature and its mechanical properties deteriorate rapidly with exposure toelevated temperature. The CFRP sheet or plate itself cannot provide sufficient insulation to the composite system. Therefore, application of a suitable insulation onto the CFRP sheet is important, especially in the application to buildings.In this study the behaviour of insulated CFRP/concrete members subjected to standard fire condition is explored. A finite element model, developed by using commercially available software ANSYS was used to simulate the thermal behaviour of the insulated composite structure.