Proceedings - Fifth International Conference & Exhibition on Piling and Deep Foundations, 1994, Bruges, Belgium, (DFI)
HFV amplitude control vibratory hammers: piling efficiency without the vibration inconvenience
Vibratory pile drivers were originally introduced in the late fifties with electric motor technology that leads to low frequency (900 rpm) machines from which originated significant and sometimes damaging vibrations. The replacement of electric motors by hydraulic motoros improved the frequency up to 1400-1800 rpm which reduced the propagation of vibrations. A major improvement was the launching of high frequency hydraulic vibrator (2000-2300 rpm) which significantly reduced the vibratory nuisance except for start up and stop down and would remain at a fixed amplitude. Then, the PTC-HFV amplitude control vibrator, thanks to its variable eccentricity capacity, eliminates the last inconveniences of the high frequency vibrator: the PTC-HFV vibrators start and stop without vibrating and their amplitude of vibration can be adjusted at any time to reduce noise or propagation of vibrations. They also keep their speed in hard ground and are of a great help in delicate jobs. A full range of machines is now available to enjoy the efficiency of hydraulic vibratory piling without the vibration inconveniences in sensitive environment. Four typical examples are given as well as the specifications of this new range of vibrators.
|article #791; publication #36 (IC-1994)|