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Feed for Nonstop Speed
It takes more than a
great paving team to lay some 20,000 tonnes of asphalt in just under eight
days. The German construction holding company Strabag AG built 2,230m
of motorway before the gates of Hamburg and paved low-temperature asphalt.
VÖGELE played a major role in ensuring the smooth progression on
site: the MT 1000-1 Mobile Feeder took up the mix from 14 shuttling trucks,
thus leaving the SUPER 2500 paver free to work nonstop.
The short construction period of 7.5 working days was the greatest challenge
involved in the project. Two asphalt plants with an output of 210 tonnes
per hour were available for preparation of the mix. Transportation to
the site was also highly efficient: 14 trucks were standing by, ready
to continuously supply the paving set made up of the SUPER 2500 paver
and MT 1000-1 Mobile Feeder.
Longer time available for paving thanks
to Sasobit®
For wearing course, the asphalt plants
admixed 1.5% of Sasobit® – a special bitumen additive with Sasol
wax – into asphalt containing polymer modified binder (0/8 PmB 45),
in order to obtain a low-temperature mix. In other words, low-temperature
asphalt which remains soft for a longer period of time, is prepared from
ordinary asphalt containing polymer modified binder by addition of Sasobit®.
When working on the A 25, Strabag took advantage of this particular property
of the mix to extend the time available for asphalt paving. An advantage,
from which benefited also the seven HAMM rollers for their compaction
work. The SUPER 2500, the flagship of the VÖGELE
fleet of pavers, paved the section of the A 25 motorway between Moorfleet
and Geesthacht in full-road width of 10.5m. The paver came with a SB 300
TP2 screed (basic width 3m), to which fixed bolt-on extensions and two
0.75m hydraulic extensions were fitted. All pavement courses were laid
in full-road width. Base course was paved in two 9cm layers, followed
by 8.5cm of binder course and 3.5cm of wearing course. In total, 19,850
tonnes of mix were placed. Based on the mixing plants’ output of
210 tonnes per hour, the paver operated at speeds between 3.5 and 4m/min.
The tamper was set up to 35% of its maxiumum rpm and a stroke length of
4mm. Pressure bars operated at 50 bar.
With the paver set up this way, the Strabag team paved
1720m of wearing course a day. The paver operated nonstop. There was,
at no time, any need to interrupt paving. On this job site, though, the
paving set made up of SUPER 2500 and Mobile Feeder did not even approach
the limits of its capabilities. The team, in fact, is capable of handling
a maximum of 900 tonnes per hour. The MT 1000-1 Mobile Feeder on site
enabled the VÖGELE SUPER 2500 to pave nonstop. The tracked Mobile
Feeder’s conveyor unit (1m wide) is capable of handling a maximum
of 900 tonnes per hour.
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 Return drum of non-enclosed design. |
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| Heated conveyor tunnel. |
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- Sasobit® is a bitumen additive that contains Sasol wax. - Asphalt with admixed Sasobit® melts at temperatures
as low as 100°C and reduces - The time available for compaction is prolonged substantially. - Sasobit® features excellent ageing and oxidation stability. - The product is free from metal particles and considerably
reduces emission such as - An essential advantage is the asphalt’s increased resistance to deformation. - Low-temperature asphalt is homogeneously soluble in bitumen. - Sasobit® has also proven its value in special
applications such as dam projects,
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 VÖGELE MT 1000-1 Mobile Feeder supplying SUPER 2500 paver with lowtemperature asphalt. |
 Extra storage hopper, holding 20 tonnes, placed into the material hopper of the road paver. This quantity plus up to 7 tonnes of mix in the Mobile Feeder’s receiving hopper create optimum conditions for nonstop paving. |
Nonstop paving thanks to the latest
in material transfer technology
Up to 7 tonnes of mix can be dumped from feed
lorries into the receiving hopper of theNonstop paving thanks to the latest
in material transfer technology Mobile Feeder, VÖGELE’s latest
innovation. An extra hopper holding some 20 tonnes is available to be
placed into the paver’s material hopper to further enhance storage
capacity. On jobs requiring high laydown rates such as motorway, the paver
is put in a position to operate at a clearly higher speed with the Mobile
Feeder on site – while compromising none of the quality. On the
A 25 it took seven minutes for a truckload of some 30 tonnes of mix to
be transferred by the MT 1000-1 Mobile Feeder to the road paver.
As far as the site personnel were concerned, the eight-day
job was accomplished with a minimum of stress: the site was optimally
prepared and perfectly organized. In the end, not only was Strabag AG
extremely pleased with the pavement quality and laydown rate achieved,
but also the people from the building authority who had let the contract.
Experts also confirmed that the pavement quality was clearly above standard,
a fact impressively corroborated by the planograph print-out.
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The planograph print-out shows a section of more than 1000m paved nonstop free from fault.