MARUTAI DOBOKU

A method, by transferring the vibration of the Vibratory hammer to the pile via a steel pile chuck to lessen the soil particle bonding around the pile to reduce the surface friction and point resistance of the pile, in order to drive the pile into the ground with the self-weight of vibratory hammer and the pile itself.
When no environmental measure is needed, an electric vibratory hammer is used. For less vibration and noise, an electric variable momentum type or hydro variable super-high frequency type is used.
In cases of punching through a hardened intermediary layer, into a bedrock/ gravel layer with boulder, or a long and large diameter pile, where vibratory hammer alone is not capable to apply, a water-jet or auger is used as auxiliary method, enabling to correspond with various sorts of ground or situation.

Vibratory hammer Driving Method with use of Water-Jet (Hydraulic: PTC100HD)

Vibratory hammer Driving
(Hydraulic: PTC100HD)

A method in which a steel pile or steel pipe sheet pile is installed with vibratory hammer, and when the pile reaches a set depth, hydrohammer strikes the pile head to drive the pile point into the bearing layer for optimal bearing power. In this method the level of bearing value is easily confirmed with the pile drive, and also possible to reduce the number of gears with the use of crawler crane to pull up the hydrohammer.

Vibratory hammer Driving (Hydraulic: PTC100HD) Hydrohammer Final Strike (S-280)

Vibratory hammer Driving
Hydrohammer Final Strike (S-90)

A driving method of steel and steel pipe sheet piles at minimum pollution using a hydrohammer equipped three-point pile driver. In recent years, the system was replaced by a single acting type with free falling ram. By adopting "Double Action Method" that is when a ram hammer falls, it is hydraulically pushed up, and thus the number of strike is increased for improved work speed. The bearing value may also be calculated by the amount of pile drive and its rebound.

Hydrohammer Direct Strike Method
(S-280)

S-150

SC-150

A method in which an auger screw is inserted into the hollow of a steel or steel pipe sheet pile, and rotated with an auger driver, then, the auger head installed on the auger screw point drills at the base of the pile and extract the soil via the hollow and bring out through the pile head. The pile is driven into the ground by its own weight or with a driver gear until it reaches the set depth. After reaching the depth, a hydrohammer strikes the pile head in order to drive the pile point into the bearing layer for optimal bearing capacity.

Steel Pile Hollow Injection (Battered Pile)

Hydrohammer Final Strike (Battered Pile) S-200

In the foundation consolidation method, a pile is driven into a set depth in the same manner as in the final strike method, and then using the special auger head and hollow of the auger screw to inject cement milk into the ground around the pile point to consolidate the foundation for optimal capacity.

Condition of the Hollow Injection

Hollow Injection and Upper Pile with Injection of Auger Screw into the Hollow