Abstract: A pile foundation, on top of which a structural object is placed, supported at the ground surface by a plurality of batter piles, has a pile foundation body comprising a lower plate disposed on the bottom side, an upper plate disposed on the top side, and a support post for supporting the lower plate and the upper plate, separated by a prescribed gap, to be substantially parallel. A plurality of piling holes, through which each of the batter piles pass through in a downward direction in a substantially radial form, are formed in the lower plate and the upper plate.

Abstract: [Problem] To provide a pile foundation and a pile foundation installation method for which the manufacturing to transporting of structural members and installation work at the site are simple and inexpensive, mass production and cost reduction are possible, and frost damage countermeasures and frost heaving countermeasures can be effectively performed. [Solution] A pile foundation (1), on top of which a structural object is placed, supported at the ground surface (F) by a plurality of batter piles (3), has a pile foundation body (2) comprising a lower plate (21) disposed on the bottom side, an upper plate (22) disposed on the top side, and a support post (23) for supporting the lower plate (21) and the upper plate (22), separated by a prescribed gap, to be substantially parallel. A plurality of piling holes (24), through which each of the batter piles (3) pass through in a downward direction in a substantially radial form, are formed in the lower plate (21) and the upper plate (22).