Kemroc chain cutter makes easy work of Swiss rockPublished 16/4, 2018 at 16:35
The Swiss construction company, Gubler, decided to try something new when working on the foundations of a large, new residential complex.
Using an EK 100 chain cutter mounted on a 22t excavator, the company excavated the foundations, footings and the service trenches with speed and accuracy, making easy work of the local molasse rock.
A large job site at the company’s home town of Mettmenstetten near Zurich (Switzerland) gave M. Gubler GmbH Tiefbau & Strassenbau the opportunity to try out its new EK 100 chain cutter supplied by German manufacturer Kemroc. The cutter, purchased specifically for the project, had already proved itself during the site preparation phase of the residential development project.
From a geological point of view, the town of Mettmenstetten is situated in the Molasse Basin located in central Switzerland. The difficult ground conditions present a challenge to all construction companies who regularly need to excavate foundations and trenches to lay pipes and services, with additional difficulties being presented by the overburden containing boulders once the solid bedrock is reached.
Normally the boulders are removed by hydraulic breaking before lifting out with a backhoe. This is a time consuming process for operators and machines. Using the EK100 from Kemroc’s EK (ERKATOR) range of chain cutter attachments proved to be quicker, more economical and created less wear and tear on the equipment. The unit has a patented cutter chain, with round attack picks mounted running between two cutter drums. This allows the attachment to excavate narrow trenches exactly to the width required as there is no gap between the cutter drums.
At the Mettmenstetten site, Gubler excavated 2,500 m3 of material while excavating 600mm wide trenches going down to 5m. Managing director, Markus Gubler said, “The EK 100 enabled us to keep the trench width to specification while maintaining vertical side walls resulting in significant savings in time and transport costs for the removal of broken material. In addition, we were able to use the EK100 on our 22t excavator. If we had to use a breaker, we would have had to go up to a larger size excavator. As well as saving time, a large part of the excavation was completed in 170 working hours; we also achieved significant savings in fuel costs.”
At the same time, within an area of 4,500 m2 , a total of 120 footings and the perimeter of the underground car park foundations were excavated. “We achieved the targets we set for ourselves; when it came to lining the periphery walls for the underground garage, we were able to save an enormous amount on concrete”, commented Markus Gubler. According to the experienced civil engineer, there were additional benefits from using the chain cutter. The quality of the excavations was so good that construction work could start without any delays, resulting in additional savings in transport costs and materials.
According to Gubler’s own calculations, the chain cutter had covered 50% of its cost on its first job site. As well as savings resulting from productivity, transport and material costs when compared to conventional methods, the chain cutter was also much quieter. “Compared to using a hydraulic breaker, which creates noise levels emanating from the job site of over 100 dB, with the chain cutter it was down to 70 dB,” said Markus Gubler. “The client, as well as the neighbouring residents, thanked us for completing the work with so little noise and vibration.”