| 摘要 |
PROBLEM TO BE SOLVED: To provide a civil engineering construction material which has high strength and high rigidity in the longitudinal direction in spite of light weight. SOLUTION: In the rectangular civil engineering construction material, e.g. a horizontal sheet pile, obtained by injection-molding a crystalline resin high in orientation properties, the molten resin 21 introduced into a sprue 14, after being introduced from the lower end of the sprue 14 into a runner 15 to be spread in the shape of a fan, is introduced from the lower end of the runner 15 into a cavity 11 via film gate 16. The molten resin 21 flows right in Fig. in the cavity 11, and fibrils (a bundle of polymer chains) 22 in the molten resin are oriented in the flow direction of the molten resin 21. The molten resin 21 is cooled and solidified in a mold 10 to be the horizontal sheet pile 1. The orientation of the fibrils 22 is kept even in the horizontal sheet pile 1 of a finished product. Together with the formation of a peripheral flange 3 and a horizontal rib 4, the strength and rigidity in the longitudinal direction of the horizontal sheet pile 1 are increased eminently. COPYRIGHT: (C)2006,JPO&NCIPI |
