Fire dynamics inside a large and open?plan compartment with exposed timber ceiling and columns: <i><scp>CodeRed</scp> #01</i>

There is an increasing global demand to build from timber as it a sustainable and attractive material. One of the key challenges associated with buildings their performance in fire, particular, for medium- high-rise when exposed. Research on this topic date has been performed compartments smaller than 84 m2 which does not capture fire dynamics large compartments. This paper presents first series experiments carried out inside large, purpose-built, open-plan compartment floor area 352 m2. The large-scale had fully exposed, unloaded, cross-laminated (CLT) ceiling glued laminated (glulam) columns, made adhesives that have tested exhibit char fall-off fire. At area, currently largest experiment globally. characteristics arrangement wood crib mimicked previous Poland non-combustible by Rackauskaite et al. (2021). was instrumented thermocouples measuring gas temperature compartment, above two openings, well within members. Plate thermometers were also included measure heat flux external flaming. Additionally, fixed drone-mounted cameras captured A protected steel column added calculate equivalent exposure compared standard resistance furnace test. allowed burn without fire-fighting intervention. Continuous measurements taken 48 h. ignited at one end compartment. Flames rapidly spread across other rest being involved 5 min 36 s ignition. total duration 22 30 s, time visible flaming ceased. Significant observed through openings order 3 m height but varied position travelled Analysis experimental results camera footage showed presence structure approximately doubled release rate (HRR) value expected alone. Smouldering combustion members continued hours after cessation flaming, burning several hotspots, resulting holes CLT slab. improves understanding open-plan, exposed shown issues such smouldering increase HRR need be considered deriving practical design solutions.