| 摘要 |
A rotary pile having a spiral lower end is provided to prevent a spiral drilling blade from falling and to prevent the deformation of a drilling blade or a pile body with penetration resistance when penetrating a pile to the ground. The rotary pile(100) having a spiral lower end includes a body(30) formed in a spiral type at a lower end to excavate the ground easily and opened downward to let soil of the excavated ground flow inward to reduce penetration resistance when penetrating the pile, and a spiral drilling blade(40) crooked to be same as a spiral of the bottom of the body to make an upper end(41) welded to the lower end of the body to minimize flexural stress added on the drilling blade. |
