Fire Performance and Design of LSF Wall Panels with 3D Printed Concrete and Steel Lipped Channel Sections (2025-12)¶

Conventional plasterboard linings impose a hard limit on the fire resistance of light steel frame (LSF) walls because gypsum rapidly degrades at high temperature. This study analyses whether substituting those linings with 3D-printed concrete (3DPC) can enhance load bearing fire rating (LFR) and insulation fire rating (IFR) under both standard and severe hydrocarbon fire exposures. Eighty-eight finite-element models simulated LSF walls combining steel lipped channels and 3DPC facings. Parameters varied were 3DPC thickness (25–100 mm), cavity-insulation type (rockwool or glass fibre) and infill ratio (20–100%). Critical outputs were time to reach steel temperatures of 320 °C, 490 °C and 640 °C (load ratios 0.6, 0.4, 0.2) and time to 160/200 °C on the unexposed face. Replacing 25 mm panels (IFR = 18 min in hydrocarbon fire) with 100 mm 3DPC panels extended insulation fire resistance beyond the 240-min analysis window; under the standard curve, 50 mm panels already sustained the 0.2 load ratio for over four hours. Rockwool increased IFR by up to 55% and added more than 60 min to LFR. Regression models linking thickness, fill, fire severity and insulation type achieved R2 values to 0.992. This is the first systematic investigation of 3DPC-LSF walls under both rapid-rise hydrocarbon and standard fires. It supplies design-ready regression models and shows that 3DPC walls = 50 mm, especially with rockwool, deliver multi-hour structural and insulation fire resistance, up to 50% higher than plasterboard, making them a viable, fire-robust alternative for fire-safe LSF construction.