The invention relates to a pile-driving device and a method for driving driving material into a ground, wherein, for the purpose of driving-in, the driving material is clamped and held by means of a clamping means on a pile-driving power unit and prior to clamping the driving material is connected by means of a flexible securing element, in particular a securing chain, to the pile-driving power unit. In accordance with the invention a pressing element is provided which is displaced relative to the pile-driving power unit towards the driving material and, in doing so, a pressing force is applied onto an upward-directed front face of the driving material.

An underground construction device includes a hydraulic assembly having an internal combustion engine and a hydraulic pump driven by the internal combustion engine, a work device connected with the hydraulic assembly in a hydraulic circuit for introducing material to be pile-driven into the ground, a clamping apparatus connected with the work device for holding a material to be pile-driven, in clamped manner, which device has a hydraulic clamping cylinder, as well as a controller for opening and closing the hydraulic clamping apparatus. A further hydraulic pump for building up the clamping pressure of the clamping cylinder of the clamping apparatus is provided, which pump is operated by an electric motor. A method operates such an underground construction device.

A pile includes a first pile section having a first end that engages a supporting medium and an opposing second end. A first end of a second pile section is engageable with the second end of the first pile section, each of the first and second pile sections having mating end fittings that create an interlocking fit. A sleeve overlays the first and second engaged ends of the first and second pile sections. At least one through hole aligned with at least one corresponding through hole of the first pile section is sized for receiving a fastener for securing the sleeve to the first pile section. In another version, the ends of the pile section are engaged in contact while the overlaying sleeve has a pair of interlocking sleeve or coupler portions that are configured to provide torsional resistance. Additional pile sections can be sequentially attached to the second pile section.

A pile includes a first pile section having a first end that engages a supporting medium and an opposing second end. A first end of a second pile section is engageable with the second end of the first pile section, each of the first and second pile sections having mating end fittings that create an interlocking fit. A sleeve overlays the first and second engaged ends of the first and second pile sections. At least one through hole aligned with at least one corresponding through hole of the first pile section is sized for receiving a fastener for securing the sleeve to the first pile section. In another version, the ends of the pile section are engaged in contact while the overlaying sleeve has a pair of interlocking sleeve or coupler portions that are configured to provide torsional resistance. Additional pile sections can be sequentially attached to the second pile section.

A method and apparatus place an auger grouted displacement pile or helical pile in soil. The pile has an elongated shaft with at least one lateral compaction protrusion which establishes a regular circumference in the supporting medium. The pile also has a helical blade configured to move the pile into the supporting medium. The bottom of the shaft includes means for forming irregularities in the circumference after compaction by the lateral compaction protrusion. The bore is filled with grout while leaving the pile in the soil.

A method and apparatus place an auger grouted displacement pile or helical pile in soil. The pile has an elongated shaft with at least one lateral compaction protrusion which establishes a regular circumference in the supporting medium. The pile also has a helical blade configured to move the pile into the supporting medium. The bottom of the shaft includes means for forming irregularities in the circumference after compaction by the lateral compaction protrusion. The bore is filled with grout while leaving the pile in the soil.

A method and apparatus place an auger grouted displacement pile or helical pile in soil. The pile has an elongated shaft with at least one lateral compaction protrusion which establishes a regular circumference in the supporting medium. The pile also has a helical blade configured to move the pile into the supporting medium. The bottom of the shaft includes means for forming irregularities in the circumference after compaction by the lateral compaction protrusion. The bore is filled with grout while leaving the pile in the soil.

A method and apparatus place an auger grouted displacement pile or helical pile in soil. The pile has an elongated shaft with at least one lateral compaction protrusion which establishes a regular circumference in the supporting medium. The pile also has a helical blade configured to move the pile into the supporting medium. The bottom of the shaft includes means for forming irregularities in the circumference after compaction by the lateral compaction protrusion. The bore is filled with grout while leaving the pile in the soil.

Foundation for a tower of a wind turbine with at least three columns. The foundation includes a reinforced concrete pile corresponding to each of the tower columns. According to one embodiment the pile includes a bolt cage and a main reinforcement formed by a cylindrical framework made up of horizontal rings interconnected by vertical bars. The bolt cage is arranged inside the main reinforcement radially at a distance of less than 0.1 meters. Each of the piles resides in a hole formed in the ground. Concrete is not poured into the holes until the main reinforcements and bolt cages are placed therein and aligned with one another.

Foundation for a tower of a wind turbine with at least three columns. The foundation includes a reinforced concrete pile corresponding to each of the tower columns. According to one embodiment the pile includes a bolt cage and a main reinforcement formed by a cylindrical framework made up of horizontal rings interconnected by vertical bars. The bolt cage is arranged inside the main reinforcement radially at a distance of less than 0.1 meters. Each of the piles resides in a hole formed in the ground. Concrete is not poured into the holes until the main reinforcements and bolt cages are placed therein and aligned with one another.