Fire Resistance of the Korean Asymmetric Slim Floor Beam Depending on Load Ratio

Abstract

In Korea recently, interest is increasing in slim floor systems that have superior structural performance and fire resistance. This paper contains the results of tests to confirm the fire resistance behavior of the composite asymmetric slim floor beam. The fire resistance behavior was analyzed using the finite element program ANSYS and the finite element models were validated against the test results. The validated thermal and structural models were used to predict the fire resistance of the Korean asymmetric floor beam and the average temperature of the steel bottom flange depending on load ratio changes. As a result, the 346ASB and the 350ASB were found to have 60 minutes of fire resistance when their load ratios were under 0.47 and 0.48 respectively without additional fire protection. Also, the authors have set the average temperature of the bottom flange, which has a direct impact on the ASB system, as a limiting temperature that enables gauging of its fire resistance as a table according to the load ratio, and presented the limiting temperature as a regression equation according to the fire resistance time.