AXIAL REINFORCEMENT OMNIPRESENCE-TYPE COMPOSITE CONCRETE PILE AND ITS MANUFACTURE

摘要

PURPOSE:To form a concrete pile having high bending strength at low cost by a method in which axial reinforcement bars of more than a specific number are contacted with the inner surface of an outer tube over the whole length of each axial reinforcement bar at equal intervals and buried with concrete layer by positioning them in an omnipresence manner toward the peripheral side. CONSTITUTION:Flat steel plates 12 as a kind of axial reinforcement material are set in 6-20 numbers, preferably 8-12 numbers, at equal intervals in the circumferential direction and fixed to a ring spring 13 to form an axial reinforcement bar cage 17. An outer tube 10 is fit on the outside of the cage 17, and ready-mixed concrete containing an expandible material is charged into the outer tube 10 and molded centrifugally. Since the axial reinforcement bars are positioned in an omniprence manner on the outermost side of the concrete layer 15, max. bending resistance effects can be obtained by using smallest number of axial reinforcement bars.