Unusual asphalt compaction project

• Hamm AG deployed two HD 12e electric tandem rollers to enlarge the Rabenleite high-level reservoir for a hydroelectric plant.

• The rollers effectively handled steep slopes of around 40%, requiring minimal modifications compared to diesel machines.

• Safety was ensured by connecting the rollers with steel wire ropes and securing them to an excavator for controlled operation.

• The electric rollers delivered precise compaction with low noise and zero local emissions, leading to planned use in future projects.

Two HD 12e tandem rollers impress on steep slopes

Advertisement

On such challenging construction sites, the demands faced by man and machine are rather unusual. Two electrically-powered HD 12e tandem rollers from Hamm AG were deployed during the enlargement of the Rabenleite high-level reservoir for the Reisach pumped-storage hydroelectric plant in the Upper Palatine Forest.

HD 12e electric rollers in action for a hydroelectric plant

Ensuring a sufficient head of water for a pumped-storage hydroelectric plant is not necessarily an everyday task for a compact tandem roller on a construction site. As a part of the Reisach project, the Rabenleite high-level reservoir was enlarged to significantly increase its storage capacity. The construction measures enabled the storage capacity of the reservoir to be increased by around 6% from the previous 1.5 million cubic meters. The ring dam of the reservoir had a circumference of 1600 m and the height of its crest was increased by 77 cm.

Electric machines show their strengths on steep slopes

The steeply sloping bank of the dam around the reservoir presented an extraordinary challenge for the technology and machines deployed on the project. Conventional, diesel-powered machines would have needed extensive modification to enable them to cope with the extreme slope gradients of around 40%. In the meantime, the electrically powered HD 12e machines from Hamm have made their mark as an uncomplicated and efficient alternative. Only minimal modifications were required to make them usable on such steep slopes.

Focus on safety & precision

To ensure maximum safety, the two machines were connected to one another with steel wire ropes and additionally secured by hitching the wire ropes to an excavator. When one of the machines went down, the other was automatically pulled up the slope. In addition to the safety aspect, the two machines also delivered even and precise compaction of the special asphalt.

Follow-up projects in planning

The two Hamm rollers impressed not only with high compaction performance, but also with their reliability in the face of extraordinarily challenging conditions. At the same time, the noise levels during compaction were significantly lower and they worked with zero local emissions. In view of the positive experiences gathered here, the machines will soon be working again on one of the customer’s upcoming projects in Switzerland.

The positive résumé of everyone involved: The project at the high-level reservoir showed that the electric tandem rollers are not only powerful machines, but are also a perfect solution for extremely challenging conditions.