Fire Resistance of Protected Composite Slab With a Stiffened Lower Flange Steel Deck

This study developed a simplified method to evaluate the fire resistance of composite slabs with steel decking protected by a novel steel shield. A numerically validated model, incorporating experimental data, demonstrated that the steel shield increases insulation failure time by approximately 25% (criterion I) and significantly reduces temperatures in critical zones. New empirical coefficients (b i c i ) were calibrated for use with the EN 1994‐1‐2 simplified method, enabling accurate prediction of the thermal and structural behaviour of this system. Mineral wool insulation provided even superior performance. The research offers a practical design tool for engineering more efficient and fire‐safe composite slabs.