Experimental and numerical investigation on temperature field of stainless-steel core plate exposed to fire considering cavity radiation effects

This study investigates the influence of various parameters on the thermal performance of a stainless-steel core plate when a single side or two sides of the plate exposed to fire. An experiment is conducted to investigate the temperature field of the slab when a single side exposed to fire. A detailed finite element model considering the cavity radiation effects is established using the software ABAQUS. The model is validated through tests and is used to conduct a parametric study to investigate the influence of boundary conditions, thermal properties of filling material, and geometry on the temperature distribution within the stainless-steel core plate. The results show that the temperature field is not uniform when a single side of the plate exposed to the fire; however, the temperature field is approximately uniform when both sides of the plate exposed to the fire. The thermal properties of the filling material and emissivity of stainless steel in the cavity have a significant influence on the temperature distribution. The fire resistance of the stainless-steel core plate according to thermal insulation criteria (when a single side exposed to fire) is generally governed by the average temperature measured at the unexposed surface, rather than the maximum temperature. To provide adequate fire protection and resistance design, a prediction formula with equivalent thermal resistance for fire protection against increasing temperatures in the fire-exposed plate is proposed. The equivalent thermal conductivity of heat transfer in the cavity was calculated to address the modeling difficulties and provide a convenient method to model the fire resistance of stainless-steel core plates in further mechanical studies. •The temperature field of the stainless-steel core plate exposed to fire is tested.•A detailed FEA model considering cavity radiation is established and validated.•The parameters affecting the stainless-steel core plate temperature are studied.•A prediction formula for fire protection against increasing temperatures is proposed.•The equivalent thermal conductivity of heat transfer in the cavity is introduced.