| 摘要 |
PROBLEM TO BE SOLVED: To prevent a concrete pile driven into the ground from being easily pulled out by applying the constitution that a part of an end holder divided into a plurality is expanded according to the upward motion of a spherical body laid on a rod type end for expanding each part of an end member in contact with the expanded end holder. SOLUTION: An end holder 32 having three separated parts 32b on the lower part of a cylindrical part 32a is internally fixed to a pile end member 31. Also, the end member 31 has an end capable of being separated for opening integrally to the same number as the part 32b of the end holder 32 divided into a plurality. Also, a ball 33 laid at one end of a round bar 34 led through a concrete pile 30 is positioned within the three separated parts 32b of the end holder 32. Thus, when the concrete pile 30 is driven into the ground and a double nut 36 screwed to the external thread of the round bar 34 is tightened, the ball 34 moves upward together with the round bar 34. As a result, the ball 33 expands the three separated parts 32b of the end holder 32, and the end member 31 coming in contact therewith opens, thereby protecting the concrete pile 30 driven into the ground from being easily pulled out. |
