The crane on a major construction site, which was indispensable to ongoing building operations, broke down and had to be repaired as a matter of priority. As a result, four concrete mixers, filled with liquid concrete, were forced to wait for a relatively prolonged period of time before the first could be discharged. By the time the last mixer should have been emptied, the concrete had set hard in the drum.
On previous occasions, one or two workers broke up and removed the concrete from the drum using light-duty pneumatic chisels. This process, however, made a deafening noise and took three weeks. Even large demolition hammers were tried, but not every drum was able to withstand the force these applied. Dynamite not only broke the concrete but the mixing drum itself. Therefore, an effective method, causing no damage to the drum, had to be found.
Two workers, using a single Darda splitting cylinder and a light-duty hammer drill, removed all the concrete from the drum, in only five days, without causing it any damage to the drum. This proved to be the optimum solution to the problem, thanks to its speed and the cost-savings it offered through reductions in working hours and safety precautions and, in particular, through the renewed availability of the mixer truck.