| 摘要 |
The present invention provides a small bore steel pipe pile which has an excellent coupling force of steel pipe piles and enables reverse-withdrawal during rotary penetration. Moreover, the present invention prevents a leakage of a grout material during grouting and prevents a building from settling and resists pull-out resistance. According to a preferred embodiment of the present invention, the small bore steel pipe pile comprises: a lower steel pipe pile where one or more helical wings are installed on an outer surface of a lower side of a pipe body to enable rotary penetration of the ground; the upper steel pipe piles connected to be attached to and detached from an upper end of the lower steel pipe pile; a pair of shaft keys bonded to correspond to the outer circumferential surface of an upper end part of the pipe body of the lower steel pipe pile to be symmetric to each other to mutually couple the lower steel pipe pile and the upper steel pipe pile and transmit the rotational force of the lower steel pipe pile and the upper steel pipe pile; a cylindrical socket having a socket hole installed in the lower end part of the pipe body of the upper steel pipe pile to be inserted into the upper end part of the lower steel pipe pile (12); and a pair of socket keys bonded to correspond to the inner circumferential surface of the socket hole of the cylindrical socket to be symmetric to each other to transmit the rotational force of the upper steel pipe pile to a shaft key. |
