1989 年 38 巻 430 号 p. 747-751
The force in driving a nail into wood by pressing and the withdrawal resistance were measured. Among the factors affecting the force and resistance against nail of wood at various specific gravities (Hem-Fir) were the diameter of nail, nail point and type of shank.
(1) A curve for driving force and moving distance of a nail could be separated into two regions: the I-region as affected by the nail point inserted into wood and separating fibers and the II-region as affected by the friction between shank and fibers.
(2) The maximum driving force and withdrawal resistance had a linear relationship to the diameter of nail and the specific gravity of wood. The slope of nail driving force into wood in the II-region was reasonably equal to the slope of withdrawal resistance as affected by friction.
(3) The effect of screw-or ring-shank, when compared to that of common smooth-shank was recognized in the shape of curve near the maximum point and the change in residual strength with moisture conditions.