Demolishing concrete structures.
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 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
About 50% more than the cost of using pneumatic breakers on the same job.
- 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