Experimental Analysis And Model Simulation On Combustion Performance Of Wood Members In Ancient Brick-wood Buildings

Most of the ancient Chinese buildings are brick-wood structures.After years of exposure to the wind and sun,the wood moisture content is low and the wood is loose.Even if a little mars is encountered,it is very likely to cause fire and destroy the ancient buildings.It is necessary to adopt scientific and effective methods to control the fire development of ancient buildings.The opening condition and the burning performance of ancient wood have an important influence on the fire development of ancient buildings.However,the influence of ventilation openings on fire is mainly focused on modern buildings,and the research on the burning performance of ancient wood is very few.Therefore,it is of great scientific research value and practical significance to conduct in-depth research on the two.The combustion parameters of ancient wood components were obtained by cone calorimeter,and then the combustion performance of ancient wood was analyzed.The combustion parameters obtained from the above tests are put into the ancient building model.By changing the switch state of doors and windows,the influence of the change of opening condition on the development of ancient building fire is studied.The changes of the average temperature,visibility and carbon monoxide concentration inside the ancient building are observed.The results show that there are two peaks in the curves of heat release rate,carbon dioxide concentration and flue gas temperature of ancient wood specimens.The higher the intensity of thermal radiation,the higher the heat release rate and the higher the fire risk of ancient wood specimens.The critical thermal radiation flux of ancient wood is 10.34kW/m2,and the ignition point is 380.3℃.After a fire in an ancient building,opening doors and windows will make the internal temperature and carbon monoxide concentration of the ancient building rise rapidly.At this time,the staff will fire extinguish the fire,and the indoor high temperature and poisonous gas will pose a threat to their life safety.This paper provides some valuable reference basis for the study of fire simulation and fire-fighting of ancient buildings.