Abstract: A hybrid foundation structure includes a first perforation hole formed in the ground, at least one second perforation hole formed adjacent to the first perforation hole on a side surface of the first perforation hole, and a first pile and a second pile formed by mixing and injecting soil and soil solidifying agent into the first perforation hole and the second perforation hole.

Abstract: The present invention relates to a screw pile for reinforcing the ground, and in particular, a pile for reinforcing the ground which can dig the ground. The screw pile includes: a bar-shaped body with a pile hole that is a passage of air and grouting solution; a screw that is formed spirally and integrally around the body; one or more grouting holes formed around the body so that grouting solution can be sprayed; a tip expanding-reinforcing plate that has a plate shape, is coupled to one end of the body on its top, and has an air discharge hole formed through the top and the bottom in the same line as the pile hole; and a excavation bit that has one end coupled to a side of the bottom of the tip expanding-reinforcing plate and the other end with a blade, in which when the bit 500 and the screw form a hole in the ground by rotation, the tip expanding-reinforcing plate moves to the bottom of the hole and performs grounding, increasing a tip support force.

Abstract: The present invention relates to a foundation structure vertically installed on the ground, and comprising: an upper support layer 10 formed on the ground in the vertical direction; and a lower support layer 20 formed so as to extend downward from the upper support layer 10 and such that the width thereof is less than that of the upper support layer 10. The disclosed upper support layer 10 and the lower support layer 20 are structures formed from soil solidified by means of feeding and mixing an earth and soil-solidifying agent therein, and therefore are efficient and prevent overload due to boring equipment.