PURPOSE: To reduce earthquake input and stresses of an upper structure when an earthquake happens by supporting the upper structure by means of foundation piles which penetrate into the ground to a bearing bed, and pile head parts which are located upward apart from the ground surface.

CONSTITUTION: Foundation piles 1 penetrate into the ground 3 directly below an upper structure 2 to a bearing bed 4, and the pile head parts located upward apart from the ground surface support the structure 2 to separate the structure 2 from the ground 3. Further, isolation members 5 made of shield pipe, etc., being concentric with the foundation pile 1 are fitted onto the piles into the ground 3, and damping material 6 made of sponge-loke or rubber-like polymeric material are loaded between the isolation member 5 and the foundation piles 1 to structually insulate the foundation piles 1 from the ground 3. Thus, horizontal earthquake waves are not transmitted directly to the piles 1, further, from the piles 1 to the structure 2, and thereby earthquake input and stresses can be substantially reduced.