A HUGE excavation for an underground car park in Tarragona, north east Spain has caused minimal disturbance to residents and businesses by using a silenced heavy duty hydraulic hammer.
The 450-space car park will alleviate parking problems in the city.
Rambla Nova, the central avenue lined with shops and restaurants, has been converted into a 12m deep, 15m wide and 200m long excavation.
Contractor Excavaciones J Morell decided to use a heavyduty hammer because it was the quickest and most ecologically 3of limestone. Blasting could not be used in the city.
The firm used a Krupp HM4000 Marathon V hydraulic hammer.
This 7t hammer can unleash up to 13,000J of power but is fitted with the VibroSilenced Plus silencing system, which reduces noise levels by 10dB(A) 7m from the machine. This is achieved by acoustic isolation of the percussion mechanism from the hammer box, using elastic mountings and plugging of all openings.
Excavations were completed in five months.