PURPOSE: To enhance anti-earthquake property and obtain a structure foundation of high reliability by a method wherein, a wall cylinder is sunk by penetrating into a ground inside of which site piles are driven in, followed by the pouring of base concrete for the structure to be built, and the whole foundation is strengthened by the uses of wall cylinder and site piles.

CONSTITUTION: Anchors 2 are sunk and fixed at each predetermined location around a wall cylinder to be sunk into the ground. Each tip end of steel wire 3 being connected to each anchor and extending above the ground is connected to a lifting apparatus such as a center hole jack 6 passing through a vertical hole 4 which is holed at each corresponding part of the lowest end part 1a of the wall cylinder, while the jack 6 is set through a jack receptacle 5 being set at the top of the wall cylinder. By operating the lifting appatus 6, inside of the wall cylinder is excavated and the cylinder sinks penetrating into the ground, followed by the driving in of the site piles within the wall cylinder. Thereafter, a base concrete for the structure is poured into the wall cylinder to a predetermined depth using the driven-in site piles as supporters.