Engineering approach to the design of wooden fireproof structural elements based on the sacrifice-layer concept: Optimum design of the wood-based protection layers using bench-scale tests

Strategy for the development of wooden fireproof structural elements based on the sacrifice-layer concept through bench-scale tests is studied through a series of bench scale tests on the design composed of sacrifice layer (chemically untreated wood), barrier (fire retardant treated wood) and loadbearing part (untreated wood). It has revealed importance of the design of the sacrifice layer to reach the glowing combustion temperature at around the end of the heating for the achievement of self-extinguishment. It has resulted in the development of Japanese-cedar based l"hour fireproof beam only with small test apparatuses available almost everywhere, demonstrating its advantage for the technical development in the districts not accessible to large furnaces.