Abstract: A dock building apparatus comprises a cantilever arm (11) having a first portion configured to be supported on a ground area and a second portion for overhanging a construction area. The cantilever arm (11) is displaceable perpendicularly to the length of the cantilever arm. The apparatus further includes a lifting device (19) movable along the cantilever arm for bringing construction materials including foundation members from the ground area to the second portion of the cantilever arm, and a foundation building tool (15) movable along the cantilever arm for installing the foundation members in the construction area.

Abstract: A dock building apparatus comprises a cantilever arm (11) having a first portion configured to be supported on a ground area and a second portion for overhanging a construction area. The cantilever arm (11) is displaceable perpendicularly to the length of the cantilever arm. The apparatus further includes a lifting device (19) movable along the cantilever arm for bringing construction materials including foundation members from the ground area to the second portion of the cantilever arm, and a foundation building tool (15) movable along the cantilever arm for installing the foundation members in the construction area.

Abstract: A pile driving control apparatus for a pile driving system includes a hydraulic control system that controls a throttle of a pile driving hammer, and thereby controls an impact velocity of the hammer with a pile. A controller provides a control signal to the hydraulic control system. Based on the control signal, the hydraulic control system controls an impact velocity of the hammer during a subsequent hammer stroke. The controller may determine one or more control parameters such as sound pressure at a sound control location during a hammer stroke, vibration at a vibration control location during a hammer stroke, an impact force imparted to the pile during a hammer stroke, and/or actual pile capacity of the pile, and provide to the hydraulic control system a control signal based on the determined control parameter(s).

Abstract: A pile driver comprises a hammer for impacting a pile, a velocity sensor for measuring the velocity at impact, and a control system for adjusting the hammer stroke in accordance with the readings from the velocity sensor so that the optimal impact energy is imparted to the head of the pile. Optionally, the system further comprises a pile driving analyzer (including at least one strain gauge and/or an accelerometer) mounted on the side of the pile itself to determine whether the impact loading on the pile is below the maximum allowable stress. If the pile driving analyzer senses an overload of stress on the pile, the control system will reduce the velocity of the subsequent hammer stroke so that it no longer exceeds the maximum allowable stress.

Abstract: A pile driver comprises a hammer for impacting a pile, a velocity sensor for measuring the velocity at impact, and a control system for adjusting the hammer stroke in accordance with the readings from the velocity sensor so that the optimal impact energy is imparted to the head of the pile. Optionally, the system further comprises a pile driving analyzer (including at least one strain gauge and/or an accelerometer) mounted on the side of the pile itself to determine whether the impact loading on the pile is below the maximum allowable stress. If the pile driving analyzer senses an overload of stress on the pile, the control system will reduce the velocity of the subsequent hammer stroke so that it no longer exceeds the maximum allowable stress.

Abstract: A tool is provided for use in submerged condition for installing anchor or foundation elements such as piles in a ground formation that is submerged under a body of water. A hammer body is fixedly supported in axial alignment with the head of a pile that is to be driven and carries a reaction body guided for movement thereon in a direction that is axial to the pile. The hammer body and reaction body define opposed first and second ends of an expansion chamber. A pyrotechnic charge is initiated to create a rapidly expanding volume of high pressure gas in the expansion chamber to generate a downwards pressure force pulse to drive the pile, an equal and opposite upwards pressure force pulse being applied to the reaction body. Damping structure operatively associated with the reaction body interacts with the water in which the tool is submerged using the inertia of the water to resist upwards movement of reaction body.

Abstract: An energy transfer unit is designed for use in conjunction with a pile driving that has an impact block projecting from the lower end of the hammer casing and axially movable therein for transmitting energy from the hammer to a pile to drive the pile. The unit comprises a housing for rigid attachment in axial alignment with the casing of the hammer, the housing receiving and guiding the projecting portion of the pile driver impact block for axial movement therein. A striker plate is guided for axial movement in the housing and is adapted to be impacted by the impact block and to transfer and distribute the impact force from the pile driver evenly and directly to the head of the pile. Cushioning rings within the housing prevent impact between said striker plate and the pile driving hammer housing upon rebound of the pile, and thus prevent damage to the pile driver.

Abstract: A test system for caissons, piles and the like provides an improved way of testing the load bearing capabilities of such inground foundation elements. The test method involves supporting an inertial mass, e.g. of concrete rings, on the upper end of a columnar foundation element that is installed in the ground and generating in a chamber defined between the underside of the inertial mass and the upper end of the foundation element over a limited duration a propellant gas pressure sufficient to accelerate the inertial mass upwards away from the upper end of the foundation element and at the same time to produce a downwards reaction force of a predetermined desired magnitude on the element. The rate of increase of fluid pressure is controlled such that the reaction force does not damage the foundation element. The magnitude of the downwards force and the response of the foundation element are measured by suitable instrumentation.