CONCRETE PIN AND MANUFACTURING METHOD THEREFOR

摘要

PROBLEM TO BE SOLVED: To provide a concrete pin capable of preventing the generation of crevice on concrete at placing, and having excellent drawing stress after placing. SOLUTION: A body portion 2 is concentrically provided with a head portion having a larger diameter than the body portion 2 at one end, and a shell-shaped tip end portion 4 having a smaller diameter than the body portion 2 at the other end. A tapered step portion 6 increasing diameter from the tip end portion 4 toward the body portion 2 is formed at a border between an end portion of the body portion 2 and the tip end portion 4, and a large number of grooves 7 inclining to an axis of the body portion 2 is provided on an outer peripheral surface of the body portion 2. By increasing of a surface area of the body portion 2 and rotational entering of the grooves 7 at placing, drawing stress after placing is improved.