Temporal Variation of Charring Depth of the Wood-Frame Walls in Fire

In this study, temporal variation of charring depth of wood studs inside wood-frame walls (WFWs) in fire was investigated. First, the time variation in the surface temperature of wood studs inside WFWs was deter-mined based on ISO 834 fire-resistance tests, and the resulting heating conditions were used in subsequent heat exposure tests. Then, wood stud specimens of four different wood species (Chinese fir, Japanese cedar, southern pine and spruce) were each subjected to a heat exposure test in an electric furnace. The results exhibited no significant correlation be-tween the charring depth of the wood stud specimens and the preheating density. In addition, the test data validated that the equation proposed by Sugahara can be used for predicting the charring depth of wood studs in-side WFWs in a fire.