Steel pipe micro-pile foundation system and construction method of micropile foundation using the same

摘要

The present invention relates to a basic steel pipe micro-pile system and a basic micro-pile construction method using the same, which are able to punch a weak ground, to install a metal pin in the ground, and to inject an injection material called a grout solution in general, thereby transferring the load of a structure transferred through the metal pin towards the ground with a firm ground on the bottom side. According to the present invention, the basic steel pipe micro-pile system comprises: a micro-pile which comprises: a hollow settlement unit installed in the ground right after or at the same with punching the ground to transfer a load transferred from the top side to the adjacent ground and to have an external diameter shorter than the diameter of the punching; and a load unit formed on the top end side of the settlement unit; a punching bit unit to punch in the size of an external diameter of the micro-pile or greater, to pull the micro-pile, and to get smaller after the punching is ended, thereby being recollected through an internal diameter of the micro-pile; an injection material to fill the space between the inside of a punched wall and the settlement unit and to make the settlement unit one body with the adjacent ground; and a basic unit made of ferroconcrete formed to bury the load unit inside. The micro-pile is made of a plurality of steel pipes with a certain length. The settlement unit additionally comprises a connection structure body to wrap around and fixate the external side of an adjacent steel pipe, and transfers and supports the load of a building on the top side of firm ground near the settlement unit through the load unit made as one body with the basic unit. The present invention is to provide a basic steel pipe micro-pile system and basic micro-pile construction method using the same, which are able to reduce the volume of used steel by not using a casing which has no function after the end of construction.