WOOD RESEARCH Volume 63, Number 4, 2018
Zuzana Kamenická, Jaroslav Sandanus, Lukáš Blesák, Kamila Cábová, and František Wald

Methods for determining the charring rate of timber and their mutual comparison

There are simplified and advanced design methods for the determination of the mechanical resistance of timber structures in fire. The simplified methods have some limitations and in case it is not possible to use the simplified methods, it is necessary to use the advanced ones. These advanced design methods can be analytical or numerical. This contribution deals with the determination of the one-dimensional charring rate depending on time by advanced calculations, focusing on the influence of different input parameters, with the results of an experiment being presented for comparison. The aim of this paper is to show that despite the suitability and conservativeness of the method according to Eurocode 5, there are various cases (different moisture, wood species etc.) when it is necessary to perform numerical or analytical analyses without the possibility to apply standard input parameters. Therefore, this contribution compares individual methods for finding of the most appropriate one.

WOOD RESEARCH Volume 64, Number 3, 2019
Hung-Chi Su, Shu-Fen Tung, Chun-Ta Tzeng, and Chi-Ming Lai

Variation in the charring depth of wood studs inside wood-frame walls with time in a fire

In this study, the variation in the charring depth of wood studs inside wood-frame walls (WFWs) in a fire was investigated. First, the time variation in the surface temperature of wood studs inside WFWs was determined 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 between 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 inside WFWs in a fire.