| 摘要 |
<p>Strut for use as bar for gymnastics is composed of wood and plastics, the latter preventing cracking and/or splintering of the strut, which is predominantly subjected to flexural stresses. The strut is suitably tubular and composed of an epoxy or polyurethane (which may be porous), reinforced with glass-fibres. The tube is wood-veneered, the veneer being glued to the underlying matrix. The veneer is relatively much thinner than the wall of the plastics tube, the ratio of the veneer: plastics thicknesses being 1:20-5:1.</p> |
