Combustion performance of engineered bamboo from cone calorimeter tests

Abstract

The combustion and charring properties of two types of engineered bamboo for structural applications: laminated bamboo sheets and bamboo scrimber were investigated through cone calorimeter tests conducted at three levels of heat flux, 25, 50 and 75 kW/m². The test was conducted with the grain both perpendicular and parallel to incident heat flux. The ignitability and combustibility parameters of these two types of engineered bamboo were calculated and the time to ignition, heat release and mass loss rates, specific extinction area, effective heat of combustion, and carbon monoxide and carbon dioxide yield were compared. Based on observations for timber, the average measured charring rates from the cone calorimeter tests at a heat flux of 50 kW/m² and exposure time of 30–60 min were taken as equivalent charring rates for standard furnace tests and compared with those promulgated by European and Australian standards. Bamboo scrimber, having a density almost twice that of laminated bamboo, demonstrated superior fire performance in all parameters considered and approached the performance of a representative hardwood. The orientation of the grain was observed to have negligible influence on their charring performance for laminated bamboo, while for bamboo scrimber, the charring rate when the grain was perpendicular to the incident heat flux was slightly smaller than when the grain was parallel to incident heat flux. Finally, this study demonstrates the utility of the relatively inexpensive cone calorimeter test, for the rapid assessment of combustion and particularly charring performance of bamboo.