ON SHOCK LOADING THE KARAMATSU WOOD FOR PROTECTING THE FIRE

摘要

Sugi (Cryptomeria japonica D.Don) wood generally has the so-called black heartwood, which contains the extremely high moisture content. Although subjected to the drying process, it is difficult to be dried up completely so that Sugi wood does not have the sufficient strength for use. The reason 4s that during drying process, the bordered pit membrane on iracheids closes faster near the heartwood in Sugi wood so that the internal moisture is not easily come out to the outside. At the mean time, it also makes very difficult to saturate the rotten-proof and/or the fireproof chemicals into the dried Sugi wood to have it become an additionally valuable wood. In this paper, we will develop an underwater shock wave technique to treat the pre-dried wood for the improvement of the drying property as well as the permeability of Sugi and/or Karamatsu (Larix kaempferi Carriere) wood by selectively fracturing the bordered pit membrane. The result indicates an improvement on the drying property and the permeability and the improvement of fireproof characteristic by the saturation of fireproof chemicals into wood can be confirmed.