Around 50 overground high-rise bunkers from the Second World War still dominate the cityscape in Hamburg to this day. They are now gradually being demolished to create new living space in coveted parts of the city. This is also the case for the bunker in Eimsbüttelerstraße, which will soon be replaced with an apartment block.
The demolition alone is an extremely expensive process and is being carried out expertly by the specialists from Abbruch und Verwertungsgesellschaft Nord GmbH (AVG Nord). They have developed a special process for gentle, selective demolition, where emissions levels are kept significantly lower than with conventional demolition methods, such as using breakers. The concept is particularly suited to the use of Erkat's robust drum cutters, which are renowned for their efficient, yet extremely low-vibration, quiet operation.
Two Erkat transverse drum cutters (types ER1500 and ER2000) are mounted on Doosan DX340 crawler excavators which are being used to demolish the high-rise bunker. Because the work is being carried out in stages from top to bottom, the machines were initially lifted onto the bunker roof by a 220 tonne mobile crane. Working up above the clouds is no problem for the high-quality drum cutting units. Thanks to their robust design and high resistance, each drum cutter can demolish around 3 cubic meters of reinforced concrete per hour. Even with a total volume of 4,500 cubic meters, the work will still take several months.
The picks on each drum cutter are checked for signs of wear every 20-minutes. The daily consumption is around 30 units. So it's even more important that the efficient Erkat-Quicksnap safety mechanism is extremely user-friendly and enables quick and easy pick changes.
While the noise levels are kept in check during this project by the specially designed protective walls, potential vibrations are a major concern. Due to the close proximity of the neighbouring buildings (0.7 m) and the difficult ground conditions (sand, clay, peat and a high proportion of water), vibrations can be easily transferred.
But the Erkat drum cutters once again proved their worth, working quietly and with low vibration levels despite their impressive demolition performance. This makes them ideal for use in sensitive areas like this. The two highly experienced excavator operators are also extremely impressed by the numerous advantages. Based on their experience, no other attachment tool is better suited for tricky demolition work like this. The high-quality cutting units have already proven themselves as the most robust and reliable machines of their kind on many other construction sites. Minimal maintenance, quick pick changes and cutting heads with replaceable wear parts prolong the service life and help to keep operating costs low.