For many customers in Asia the hydraulically powered silent piler, especially when powered by a highly silenced power pack, is the method of choice when the disturbance to the environment in vibrations or noise must be kept to an absolute minimum. While in Europe advanced resonance free vibratory hammers are used when surrounding areas need to be free from piling impact.
 
The silent piler overcomes soil friction by force; as much force as is necessary to drive down a sheet pile is applied. Brute force is applied to reach designed depth. The piler is most suited to clay soils, as stones and pebbles that are in the driving path are spliced by the driving force. Silent pilers are self-propelling, they move along driven sheet pile walls with an internal mechanism. This process requires ample organization on site, as repositioning the equipment is time intensive. The driving speed of the pile is fixed by the speed of hydraulic press regardless of soil conditions. Operators need specialist training to operate the equipment, to handle complex maneuvers such turning corners.
 
The resonance free vibratory hammer uses a different mechanism: the hammer’s amplitude changes the friction of the soil by liquefaction of the soil particles, facilitating the driving of the sheet pile. Stones that are in the driving path are pushed aside by the vibrations clearing a path for the sheet pile. Vibratory hammers are either crane suspended or fitted to the boom of an excavator. They are moved around the construction site quickly and can be used with little prior planning. The compact size of the equipment allows the hammer to operate in confined spaces. Vibratory hammer’s driving speed is dependent on soil conditions and in easy driving conditions can be much faster than the pressing method.
 
What is resonance free technology?
Conventional vibro hammers have a constant eccentric moment. When passing the critical frequency area during start-up and stop, the constant amplitude will cause disturbing negative vibrations in the boom of the crane and in the soil; not just at the working area, but with a considerable perimeter distance. When working in highly urbanized areas or in the vicinity of fragile structures this may cause damage to nearby structures. In applications such as these regular vibratory hammers may not be a feasible choice and contractors will need to opt for a high frequency vibro hammer instead.

When using an ICE high-frequency (Variable Moment) vibro hammer with an adjustable moment of 0 to max 2300 rev. per minute, critical vibrations in start-up and stop are eliminated. After passing the critical frequency area, the eccentric weights are automatically adjusted and synchronized to the current eccentric moment.
 
The benefits of working with ICE Resonance Free technology are: cost effective, agile and lightweight excavator mounted or crane suspended hammer, with minimal disturbance to the surroundings. Ideal for cramped working conditions close to sensitive areas.