Fire reaction properties of bio-based aggregates used in thermally insulated building components

Abstract

Bio-based aggregates can be seen as one of the promising alternatives to reduce the environmental impacts of buildings due to their lower carbon footprint and energy efficiency. They have great potential to be incorporated into inorganic matrices and produce insulating materials. However, there is a lack of information about the flammability of these materials. This work presents the results of an experimental investigation of the fire behaviour of bio-based materials. In this study, wastes of bamboo, wood shavings and rice husk were used and were evaluated for their fire performance in the natural state and after treatment in an alkaline solution. The fire reaction properties were determined by using a Mass Loss Cone Calorimeter in order to obtain the parameters of heat release rate (HRR), total heat released (THR), effective heat of combustion (EHC), total mass loss (TML), ignition time (IT) and time of combustion (TC). In addition, physical characterization and thermogravimetric tests were carried out as well as scanning electron microscopy analyses. The results show that the alkaline treatment of the bio-based aggregates is able to reduce the average HRR and the EHC of all bio-aggregates but does not delay the ignition of these materials. Among the residues studied, rice husk presented the lowest peaks and averages of HRR, THR, total mass loss, EHC and time to flameout; however, the ignition occurred faster.