Maximum performance on glacier
A man-made reservoir with the name „Panorama“ has been created at an altitude of almost 3,000 m at the foot of the Tiefenbachferner, a glacier in the Ötztal Alps. As of 2011, it will supply the water for an artificial snowmaking facility. To make the reservoir basin, 270.000 m³ of granite were blasted out of the mountain, 120.000 m³ of which were crushed by a Kleemann crusher and compacted into an embankment by a Hamm 3520 HT single drum compactor equipped with GPS Navigator.
Global warming has caused the glacier in Ötztal to continuously melt over the past 40 years at a rate of one meter per year. „Technical Snow“ produced from the water collected in the new reservoir is intended to halt this process in future. Austria‘s largest man-made lake has a volume of 405,000 m³, a water depth of 17 m and a water surface area of 35,000 m². It was created by blasting granite from the mountain. Crushers, including a Kleemann MC 110 R mobile jaw crusher, comminuted the stone directly on site to a grain size of 0/160. The building material was transported via dump truck to the Hamm singledrum compactor a few meters away, which created the embankment in up to 45 layers, each 50 cm thick.
GPS Navigator: simple compaction control across the entire surface
In order to verify the compaction results, the single-drum compactor was equipped with the HCQ GPS Navigator. When Site Manager Alexander Hauser from construction company Hilti & Jehle in Vorarlberg opted for this technology, he was making an informed choice: „Compaction control across the entire surface was mandatory for this project. With the GPS Navigator, Hamm is the only manufacturer in this sector who offers an easy-to-use solution.“ The system continuously measures the compaction and links the measurements to the respective position. This produces a „compaction map“, on which the machine operator can see the degree of compaction and the number of passes completed. After the compaction work, Hauser, himself an engineer, stored the data on a USB stick. „The HCQ GPS Navigator provides unequivocal and immediately comprehensible data. That greatly facilitates the documentation process,“ said the Site Manager in praise of the system.
Hammtronic: reliable even in extreme conditions
The 20-t single-drum compactor on the embankment was also equipped with „Hammtronic“. The engine management system monitors all engine and vehicle functions and matches the vibration and vehicle speed to the operational conditions. Hammtronic also reacts to environmental factors and adjusts the machine parameters accordingly. At this high altitude, that turned out to be a major advantage, as Hauser reports „Quite a few machines had problems with engine failures during the project. However, the machines of the Wirtgen Group worked on continuously despite the high altitude and low air pressure.“
HIGH ALTITUDE – SHORT CONSTRUCTION WINDOW
The construction season is short in high-alpine regions. In „good construction years“, it is possible to work for 5 months at altitudes of around 3,000 m. Snow and ice prevent other activities for the rest of the year. Another challenge is transportation: it takes great effort to move all of the machines, equipment, operating materials and spare parts to such high altitudes. This kind of work calls for reliable and efficient machines with endless stamina, so that construction projects can be completed economically and on time. The „Panorama“ reservoir was built over two construction summers. After work commenced in late spring of 2009, Hilti & Jehle began constructing the embankment in the summer. The Hamm compactor was able to work for two months before winter arrived.
In 2010, the single-drum compactor with GPS was in operation for roughly five months, although obviously not continuously as work frequently had to be interrupted on account of adverse weather, such as 60 cm of fresh snowfall in early September. All told, the 3520 HT single-drum compactor processed roughly 120,000 m³ of granite in just over 20 weeks of „net construction time“. The granite places heavy demands on crushers. Hilti & Jehle were not satisfied with the performance of their crusher, so they rented a MC 110 R. The mobile jaw crusher soon impressed the company with its ease of transportation. However, what really bowled them over was the crusher‘s top performance in operation with fuel consumption of just 20 to 25 l/h and the high final product quality. The crusher processed between 200 and 350 t of blasted material every hour, depending on the grading curve for feeding material. Hermann Almer from Wirtgen Österreich oversaw the project successfully: „The performance was so impressive that the customer has purchased the rental machine.“
|Job site:||Tiefenbachferner, a glacier in the Ötztal Alps|