Evaluation of Friction Properties According to Normal Force and Direction of Wood Grain in Real Contact Area

In Korea, there has been a traditional post and beam wood construction with large roof load. Because a large friction is generated in wooden joint or members, it is important to evaluate the friction between wood members according to wood direction. Because most of studies have been concerned with friction between wood and steel, excluding effect of real area of contact, there are a few studies on the friction between wood members. The object of this study was to evaluate friction or coefficient of friction accord- ing to normal force and real area of contact of wood. With Japanese larch (Larix kaempferi) test speci- mens, five steps of normal force and combinations of test were prepared. Results indicated that normal force had almost no affection on the friction, however there was difference about friction or coefficient of friction according to real contact conditions of wood grain and contact area.