Abstract: A method of forming a base for a building structure comprises forming a plurality of holes in the ground on which the structure is to be supported, each hole diverging upwardly and pouring a mould for a concrete support column formed in situ therein, the support columns supporting beam sections forming a ring beam on which the building structure can be built.

Abstract: A soil displacement tool, or mole, comprises a hollow cylindrical body in which is provided an hydraulically reciprocal piston the movement of which drives the tool through the soil to form a hole, the body and piston being annular such that the tool is hollow.

Abstract: Several underpinning arrangements are described. In each, a concrete pile is cast in a hole formed adjacent to the structure to be underpinned. The hole is formed from at or near ground level and is vertical or at an angle close to the vertical. At least one supporting limb is also formed. This extends from the pile hole and engages the structure. When the pile is cast in the pile hole, the pile and supporting limb are made to form a unitary element so that forces exerted on the supporting limb by the structures are transmitted to and borne by the pile. Various configurations of supporting limb are described, as are various arrangements for ensuring that the supporting limb is retained in a position in which it supports the structure. A drilling assembly for use in the method is also described.

Abstract: A method of forming a support or foundation for a building structure comprises forming a number of upwardly diverging support members interconnected at their upper ends by making correspondingly shaped holes in the ground on which the structure is to be supported thereafter pouring concrete into the holes and allowing it to set to form the foundation. In certain grounds it may be necessary to extend the support structures by driving piles from their base.

Abstract: A pile section for a sectional pile including a string of sections includes a concrete member (10) having at least one longitudinally reinforcing rod (12), the rod including a spigot (14) at one end and a socket (18) at the other which in use are adapted for permanent interconnection so that on driving one section against its neighbor a continuous reinforcing element is provided.

Abstract: A method of supporting a structure comprises driving a pile casing through a hold in a structure to be supported until the leading end of the pile casing reaches its desired position and thereafter introducing a cutter into the top of the pile casing, positioning a cutting element of said cutter to a location at or near the lower surface of the structure to be supported, actuating the cutter to cut off the pile above said location so that the unwanted top portion of the pile can then be removed and introducing concrete into the pile casing and hole through the structure.

Abstract: The specification discloses a in situ cased pile and method for constructing same under the footing of a building. The invention is particularly suited to the stabilization of building footings in regions of unstable soil subject to uplift or subsistence. The cased pile extends through the unstable soil to a region of stable soil, and rests thereon. An enlarged pile footing in the stable soil is used. The movement of the unstable soil is isolated from the pile by means of a casing or tubular sleeve which surrounds the casing. A method of forming this structure in situ, without removing the unstable soil, is also disclosed. In the practice of this method a self-propelled soil displacing mole forms a hole in the subsoil and draws down a steel tube (15) to line the hole. The mole is withdrawn, a PVC or cardboard tube (16) is slid down the lined hole, and the lined hole is filled with concrete. The mole is re-run to produce a pile footing (17) and is again withdrawn.

Abstract: A method of installing a pile beneath the foundations of a building comprises forming a hole, preferably at a small angle to the vertical, through the foundation driving a first pile casing section through said hole into the ground beneath the foundation with a percussive machine located at or near floor or ground level of the building, applying to the end of the first pile casing section a further pile casing section and driving the composite pile casing into the ground by a percussive machine located no lower than the floor or ground level of the building, fitting a further percussive machine having a maximum external diameter no greater than the maximum external diameter of the foundation hole and driving said casing further into the ground with said further percussive machine following the casing into the ground, completing said further driving operation before said further percussive machine penetrates completely below floor or ground level, withdrawing said further percussive machine and thereafter inse