Research of Charring and Resulting Char in Natural and Treated Timber

Abstract

Wood is a material widely used for construction purposes, which has quite a number of advantages in comparison with other materials – it is light, strong, resistant to impacts and vibration, easy to process, etc. However, one of the largest drawbacks of wood – it is flammable. In case of fire in wooden buildings or buildings made of timber structures, the most noticeable feature of combustion is charring of these structures. This property is important in identifying the cause of a fire. Therefore, it is necessary to relate charring of timber structures with certain significant effects of fire, such as its duration and temperature. It is also important to identify whether timber has been treated with fire retardant solutions before the fire break-out. The article analyses the wood properties that have influence on combustion and charring processes. The indicators of charring, and calorific values, the electrical resistance and electrical capacitance were determined for char resulting in natural and treated timber under different conditions. Microscopic examination was carried out. The research results were summarised by conclusions.