HAMM VC compactors

Efficient process while reducing costs

Sauerland/Bad Fredeburg

VC compactors are designed to streamline the construction process, removing the need for a separate stone crusher, and reducing the amount of transport required. This results in a faster process with lower costs.

When constructing a dam with a height of 15 m for a bypass in Bad Fredeburg in the Sauerland region, two HAMM H 25i VC compactors, with their special crusher drum, were used to simultaneously crush and compact the local "Fredeburger" slate. The plate material was originally supposed to be broken to a maximum particle size of 200 mm on the construction site using several jaw crushers, and transported to the dam on a truck. Bulldozers would have distributed the stone there, and compactors would have carried out the compaction in layers. The two H 25i VC compactors were the considerably simpler and more efficient alternative here.

"As soon as I saw the stone, I had a feeling that the HAMM compactor would be perfect for crushing this material."

Michael Tillmann, Construction Manager at Straßen- und Tiefbau GmbH in Kirchhundem

Searched for and found: The optimal construction measure for the VC compactor

At bauma 2019, Michael Tillmann, from Kirchhundem in the West-German low-mountain region of Sauerland, noticed the H 25i VC compactor. "We were immediately won over by the roller's design. But we never had the right project before," explains Straßen- und Tiefbau GmbH's construction manager. Not long after, there was a project to build a dam for a new bypass using locally available slate.

Without crushers, with significantly fewer transports, but using two compactors: It quickly became clear that the VC compactors from HAMM produced the right fracture pattern for the application.

Process parameters

Material for dam construction:: 260,000 m³
Of which is slate:: 180,000 m³
Removal:: Up to 14 m
Structure:: In layers up to 15 m

Height of the layers:: 40 cm each
Max. particle size:: 200 mm
Porosity:: Optimal 6%, max. 10%

High crushing and compaction power

During the construction, each of the two VC compactors crushed and compacted approx. 2250 m³ in layers that were 40 cm thick.

The work process

Trucks bring the stone directly to the construction site from the quarry. A caterpillar then distributes the material in 40 cm layers. Lastly, the rock crusher-compactors break up the stone and compact it at the same time.

200 mm particle size

The H 25i VC was used to crush slate to a maximum particle size of 200 mm.

Crushing and compacting in a single process

The drum on the VC compactors, which is also used in mining, landfill work or tunnel construction, for example, creates high point loads of up to 50 t per cutting tool, whereby the material can be effectively crushed. Thanks to the vibrating drum, this is compacted to a high quality in the same work process.

Simplified process – double the performance

The site manager was also pleased with the quality of the crushed slate and the compaction achieved for the dam layers. In liaison with the soil expert, a depth of 40 cm was then determined for each layer. The optimal porosity was determined as 6%, and the maximum permitted was 10%. To ensure that the water content was also correct, each layer had to be sprayed with water.

After just a few days, it was clear that speed was now part of the construction process!

"Thanks to decoupling the process steps, we were able to achieve a performance of approx. 4500 m³ per day. This is almost twice as much as set out in the original planning schedule. The main reason for this is the work in layers."

Michael Tillmann

VC compactors – your benefits

One machine, various applications
Costs saved thanks to the optimisation of the construction site processes
Simple and fast transport
Gradeability up to 60%
Easy operation
High crushing and compaction power

Flexible quick-change system

The drum on the VC compactors has a width of 2.22 m and is equipped with 150 quick-change toolholders. Fitting and removing the tools with the VC quick-change system is extremely easy.

Three different attachments are currently available, including one tool set for hard stone and one for soft stone. Their geometries are specially tailored to materials of different compressive strengths. Furthermore, HAMM also offers a padfoot insert for cohesive material.

Multiple uses of the cutting tools

The design of the toolholder prevents contamination of the tools, and therefore ensures that the tools are easy to change. The cutting tools are not destroyed during replacement, and can be used repeatedly until their wear limit is reached.

When crushing the Bad Fredeburg slate, the cutting tool also exhibited an impressively low level of wear: "We only had to change a few cutting tools the whole time we were working," states machine operator Marvin Gallus.

Cost reduction of 50%

The costs for breaking up and compacting were reduced by approx. 50%. This is because considerably fewer machines were needed. Straßen- und Tiefbau GmbH only required two VC compactors and a caterpillar vehicle instead of the two crushers, two baggers and two dumpers originally planned for crushing the slate. Personnel and operating costs were also reduced accordingly.

Reduction of the CO2 footprint

Another benefit was that, by using the VC compactors, the CO2 footprint also significantly decreased across the entire construction site.

Heavy-duty equipment

High stress requires anticipatory measures: The three-point articulation, underbody, front frame and drum suspension, including the drive, have been further reinforced when compared to normal compactors. In addition, all VC compactors are set on highly robust earth-moving tyres, and operators benefit from a seat with an extra-high backrest. The VC compactor is also equipped as standard with the HAMMTRONIC machine control system and the HAMM Compaction Meter.

Happy users

Marvin Gallus and Mohamed Khalil were at the wheel of the two H 25i VC compactors in Bad Fredeburg and were given detailed instruction on how to use the crusher-rollers by a service technician.

Both singled out its ease of operation and comfort for praise – specifically the quality of the seat and the amount of space available in the cab. The many details designed to make work more pleasant were also much appreciated.

"We found everything very clear and simple after this. The roller is easy to use. I used one of the two 12-V sockets for a mobile phone. It is really practical."

Marvin Gallus and Mohamed Khalil, roller operators

Possible applications for the VC compactors

Crushing of basalt, granite and other minerals of comparable compressive strength
Crushing and compaction of mixed soils with great depth effect
Homogenisation of rock
Compaction during cold recycling
Crushing broken concrete
Primary crushing and relieving tension in rock
Preparing/maintaining access routes in quarries
Track-laying in tunnel construction and surface mining
Compacting cohesive soils
Compacting abrasive, fine-grain minerals