Study On The Fireproof Performance Of Fire-retardant Treated Wood Component

This paper analysised the fire resistance performance of wood. The authorselected five kinds of wood as object of study, first analysised the charring rate ofwood, and then obtained the fire-retardant wood by using pressure impregnatedtreatment, the last, measured the charring rate of fire-retardant materials and its fireresistance limit calculation formula.The results show:Wood charring rate was different in different directions after calculated, thehorizontal chrring rate was less than the vertical charring rate, the charring rate wasdifferent between different species,but the difference was smll,the average verticalcharring rate was between0.8-1.0mm/min,the average horizontal chrring rate wasbetween0.6-0.9mm/min, the horizontal chrring rate descended in order is: fir>Chinafir>spruce>pine>larch,the vertical chrring rate:pine>fir>China fir>larch>spruce.onthe base of the principle which can be used calcuating the fire resistance limit, gotthe formula of fire resistance limit of wood components in wood on three sides bythe fire, fire resistance limit calculation formula is t_f=0.08ZB(4-B/D).Using mathematical model simulation the instantaneous chrring rate of woodfound that polynomial model is suitable for instantaneous chrring rate, and the trendof the chrring rate tend to level,using the linear model to simulate the chrring rate ofwood found a good linear correlation between the simulated and experimentalvaule,this can be seen the linear model can simulate the chrring rate in a short time.Compared the chrring rate between fire-retardant material and not fire-retardantmaterial found the horizontal chrring rate small0.28,and the vertical chrring ratesmall0.23,the fire-retardant material chrring ratedeclined significantly.Through the measured mechanical properties of carbonized wood afterfire-retardant treatment, we found the strength and stiffness reduction factor of thewood is in the range of0.85to0.90, so take the flame-retardant material reductionfactor α=0.8in the calculation process is permited; test algorithm, we derived theformula of fire resistance limit is: t_f=0.12ZB(4-B/D),the fire resistance limit of woodcan be boosted by50%through fire retardant processing.