Comparative analysis of the combustion behavior of inorganic-bonded bamboo and engineered bamboo-wood composites

Inorganic-bonded bamboo composite (InorgBam) has potential advantages in improving the fire performance of bamboo-based materials owing to its organic–inorganic composite structure. In this study, cone calorimeter tests were conducted to investigate the combustion behavior of InorgBam, spruce wood, laminated bamboo lumber (LBL), and parallel strand bamboo (PSB) under a heat flux of 50 kW/m 2 , with InorgBam additionally tested at 60 kW/m 2 , and the fire-retardant effect of a water-based intumescent coating was also examined. The results showed that, at 50 kW/m 2 , only one InorgBam specimen ignited at 148 s, and its peak heat release rate (pHRR) was 18.4 kW/m 2 , corresponding to reductions of 91.5% and 93.0% compared with LBL and PSB, respectively. Meanwhile, its effective heat of combustion (EHC), mass loss rate (MLR), and overall combustion intensity were markedly reduced. Even at 60 kW/m 2 , InorgBam still exhibited lower heat release and combustion efficiency than conventional bamboo- and wood-based materials. After treatment with the fire-retardant coating, none of the specimens ignited, and HRR, EHC, and smoke release were further suppressed. The analytic hierarchy process (AHP)-based comprehensive fire hazard assessment showed that InorgBam had an integrated fire hazard index (IFHI) of 0.826, higher than those of PSB (0.424), LBL (0.404), and spruce wood (0.376), indicating the lowest overall fire hazard within the evaluation framework. Overall, the MOS inorganic bonding system effectively reduced the thermal contribution of bamboo-based composites to fire development, and its combination with an intumescent fire-retardant coating can enhance its potential for building fire protection applications.