Darda ROCK SPLITTERS
Underwater demolition - demolition on the bed of the East River
The Job:
A new power line had to be laid under water, on the bed of the East River in Manhattan, NY. The cable itself would be laid in a trench. During the trenchdigging operations, the workers hit a stratum of hard slate, over 200 m in length, at a depth of 10m under water.
The Requirements:
This posed a problem in that the site was located near the Long Island railway tunnel, making it impossible for explosives to be used.
The Solution:
Two divers, using suitable pneumatic hammer drills, drilled the necessary holes in the bed of the river after which the slate was split with two hydraulic splitting cylinders. The hydraulic equipment, mounted on a barge, was connected to the cylinders with long hydraulic hoselines. The splitter destroyed the structure of the slate, after which it was reduced with a hydraulic breaker and extracted by a dredger.
