EXPERIMENTAL STUDY ON FIRE BEHAVIOR OF INSULATED FULL-SCALE CFRP-STRENGTHENED RC BEAMS UNDER SERVICE LOAD

摘要

In this paper, a series of experimental study conducted to investigate the fire behaviour of insulated full-scale CFRP-strengthened reinforced concrete (RC) beams is presented.Four rectangular CFRP-strengthened RC beams, respectively insulated with thick fireproof coating system, ultra-thin fireproof coating system and calcium silicate board system, were tested under ISO-834 standard fire and service load.The thermal and structural response of these beams in fire were recorded and analyzed.The results show that satisfactory fire endurances for CFRP-strengthened concrete beams can be obtained with the protection of these three systems above.The major role of fire insulation materials was delaying the failure of adhesive in the early stage, and reducing the performance degradation of concrete and internal reinforced bars after the bond failure of CFRP-concrete interface.Also, it is indicated that effective anchorages of CFRP and reasonable anchoring constructions of insulation system play important roles in assuring the fire-resistant capability of CFRP-strengthened concrete beams.