Crushing concrete

The task

Demolishing concrete structures.

The problem

As part of the refurbishment of a hospital maternity block, it was necessary to demolish a 15 m long section of concrete wall. This could have been done with small pneumatic breakers which might have caused typical worker vibration exposures of 7 m/s² A(8) and created intrusive levels of noise.

The solution

The wall was cut away from the building pillars by drilling lines of overlapping holes (stitch drilling) using a diamond drill. The diamond drilling machine was held in a clamp and so the operators were not exposed to vibration. Each section was then broken up by ‘biting’ off pieces with a hydraulic concrete crusher. The jaws of this device close slowly, allowing the operators to loosen their grip before crushing takes place.

Concrete crusher demolishing a wall

Using a concrete crusher to crush a wall

The cost

About 50% more than the cost of using pneumatic breakers on the same job.

The result

The operator’s exposure to vibration is negligible.
Very low vibration is passed into the structure which helps to reduce damage and structure-borne noise.
This method is less messy than using breakers as the debris is in larger pieces and less dust is produced.
Noise levels are very low, both for the operators and the environment.

Case courtesy of Specialist Services (Cutting and Drilling) Ltd