A pile (100) includes a first elongated hollow body (101) having a first end and a second end, the first end being closed by an end member (103) provided with an opening (104). The pile (100) includes a second elongated hollow body (102) having a first end and a second end, the second elongated hollow body (102) being arranged inside the first elongated hollow body (101) so that the first end of the second elongated hollow body (102) extends through the opening (104) and is attached to the end member (103). A method is for installing a pile (100) into the ground.

Provided is a drilling apparatus, comprising a PHC pipe cased pile having a drilling section for containing fluid and a hammer element arranged inside the cavity of the PHC pipe cased pile which moves along the drilling direction till the bottom of the drilling section. As the hammer element moves along the drilling direction till the bottom of the drilling section, a localized hydraulic force will be induced in the fluid contained in the drilling section of the PHC pipe cased pile by a sharp rise in the fluid pressure in addition to the impact force directly acted on the rock and soil by the hammer element. Under action of the hydraulic force and the impact force, the surrounding soft rock stratum could be crushed and the rock stratum with higher strength is left intact, that is, the drilling apparatus proceeds until harder rock. At this point, concrete casting will bond with the harder rock, resulting in a better bearing capacity of the PHC pipe cased pile foundation.

Provided is a drilling apparatus, comprising a PHC pipe cased pile having a drilling section for containing fluid and a hammer element arranged inside the cavity of the PHC pipe cased pile which moves along the drilling direction till the bottom of the drilling section. As the hammer element moves along the drilling direction till the bottom of the drilling section, a localized hydraulic force will be induced in the fluid contained in the drilling section of the PHC pipe cased pile by a sharp rise in the fluid pressure in addition to the impact force directly acted on the rock and soil by the hammer element. Under action of the hydraulic force and the impact force, the surrounding soft rock stratum could be crushed and the rock stratum with higher strength is left intact, that is, the drilling apparatus proceeds until harder rock. At this point, concrete casting will bond with the harder rock, resulting in a better bearing capacity of the PHC pipe cased pile foundation.

The invention relates to a driving device, in particular a screw foundation driving device, having an anchor with a rotational axis for receiving a driving tool, an outer rotor, which is arranged concentrically to the rotational axis of the anchor and can be rotationally driven by a motor, and an impact device from which an impact energy can be introduced into the anchor. By means of rolling bodies arranged circumferentially on the anchor, the anchor is mounted in the outer rotor in such a way that a relative movement between the anchor and the outer rotor can be executed in the direction of the rotational axis and a torque about the rotational axis can be introduced from the outer rotor to the anchor via the rolling bearings.

The invention relates to a driving device, in particular a screw foundation driving device, having an anchor with a rotational axis for receiving a driving tool, an outer rotor, which is arranged concentrically to the rotational axis of the anchor and can be rotationally driven by a motor, and an impact device from which an impact energy can be introduced into the anchor. By means of rolling bodies arranged circumferentially on the anchor, the anchor is mounted in the outer rotor in such a way that a relative movement between the anchor and the outer rotor can be executed in the direction of the rotational axis and a torque about the rotational axis can be introduced from the outer rotor to the anchor via the rolling bearings.

A pile installing system for a pile including a cylindrical wall surrounding a hollow space, the system having a central cutter which is locatable at a lower end of the pile for loosening soil below the hollow space upon installing the pile into the ground and which is displaceable within the pile in longitudinal direction thereof so as to remove the central cutter from the pile after installing the pile in the ground, a peripheral cutter locatable at the lower end of the pile for loosening soil below the cylindrical wall, a soil passage for guiding loosened soil from below the cutters to the hollow space, and a soil conveying member for transporting loosened soil upwardly through the hollow space. The soil passage is located at at least one of the central and peripheral cutter at a radial distance from the cylindrical wall.

A pile installing system for a pile including a cylindrical wall surrounding a hollow space, the system having a central cutter which is locatable at a lower end of the pile for loosening soil below the hollow space upon installing the pile into the ground and which is displaceable within the pile in longitudinal direction thereof so as to remove the central cutter from the pile after installing the pile in the ground, a peripheral cutter locatable at the lower end of the pile for loosening soil below the cylindrical wall, a soil passage for guiding loosened soil from below the cutters to the hollow space, and a soil conveying member for transporting loosened soil upwardly through the hollow space. The soil passage is located at at least one of the central and peripheral cutter at a radial distance from the cylindrical wall.

A machine, method and system for installing helical foundation piers that sues a driving tamper connected to a rotary tool to drive helical piers into the ground. Once the pier reaches the target depth, the tamper is decoupled, and counter rotated away from the pier. While it is withdrawn the soil between the driven and pier and the driving tamper is compressed by intermittent downward action of the tamper.

A machine, method and system for installing helical foundation piers that sues a driving tamper connected to a rotary tool to drive helical piers into the ground. Once the pier reaches the target depth, the tamper is decoupled, and counter rotated away from the pier. While it is withdrawn the soil between the driven and pier and the driving tamper is compressed by intermittent downward action of the tamper.

Improved masts for solar pile driving machines are provided that incorporate inline drilling as well as alignment and assembly devices that enable greater positional accuracy than possible with conventional equipment. In some cases, a jig, holder, or other device on the mast of the machine can be used to place a bearing assembly for a single-axis tracker while the foundation is being installed. Also disclosed are various multi-piece foundation piles that enable positional adjustment between below and above-ground components to compensate for misalignment.