PURPOSE: To permit the smooth and exact withdrawal of an existing hollow pile without causing any break at a joint, etc., by a method in which drawing out the hollow pile through a drawing bar material is performed by converting the pulling force of the bar material into a pushing-up force.
CONSTITUTION: A drawing steel bar 3 is inserted into an existing hollow pile 1 buried underground from the ground's surface and the lower end of the drawing steel bar 3 is integrally fixed to the inner bottom portion of the existing hollow pile 1 with the aid of a solidifier 5. Afterwards, the drawing steel bar 3 projecting from the upper end of the existing hollow pile 1 is drawn out upwards so as to pull the existing hollow pile 1 up and then a fluid material is injected 9 into a void 12 between the outer bottom portion of the pile and the ground, which is produced when the existing hollow pile 1 is pulled up.
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