Performance of insulated FRP-strengthened concrete flexural members under fire conditions
Pratik P. BHATT1, Venkatesh K. R. KODUR1(), Anuj M. SHAKYA2, Tarek ALKHRDAJI2
1. Department of Civil and Environmental Engineering, Michigan State University, East Lansing, MI 48823, USA 2. Structural Technologies A Structural Group Company, Columbia, MD 21046, USA
This paper presents the results of fire resistance tests on carbon fiber-reinforced polymer (CFRP) strengthened concrete flexural members, i.e., T-beams and slabs. The strengthened members were protected with fire insulation and tested under the combined effects of thermal and structural loading. The variables considered in the tests include the applied load level, extent of strengthening, and thickness of the fire insulation applied to the beams and slabs. Furthermore, a previously developed numerical model was validated against the data generated from the fire tests; subsequently, it was utilized to undertake a case study. Results from fire tests and numerical studies indicate that owing to the protection provided by the fire insulation, the insulated CFRP-strengthened beams and slabs can withstand four and three hours of standard fire exposure, respectively, under service load conditions. The insulation layer impedes the temperature rise in the member; therefore, the CFRP–concrete composite action remains active for a longer duration and the steel reinforcement temperature remains below 400°C, which in turn enhances the capacity of the beams and slabs.
. [J]. Frontiers of Structural and Civil Engineering, 2021, 15(1): 177-193.
Pratik P. BHATT, Venkatesh K. R. KODUR, Anuj M. SHAKYA, Tarek ALKHRDAJI. Performance of insulated FRP-strengthened concrete flexural members under fire conditions. Front. Struct. Civ. Eng., 2021, 15(1): 177-193.
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