Compactasphalt® - game changing paving - Dynapac

Compactasphalt®
- game changing paving
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CompaCtasphalt ® offers BiG aDVaNtaGes to roaDBuilDers aND
their ClieNts. roaDs surfaCeD usiNG this methoD last loNGer
aND are Cheaper to maiNtaiN.
THE COMPACTASPHALT ®
method is revolutionising
roadbuilding. With this method,
patented in 1993 by Professor
Elk Richter at Erfurt, Germany,
and now recognised as standard
practice, the binder and the
wearing course are applied to
the loadbearing layer one after
the other in a single pass. Conventional
roadbuilding involves
two separate passes, with the
wearing course being applied
after the binder has cooled.
THE CONVENTIONAL method
poses problems here, especially
in bad weather. According
to the official ZTV Asphalt’
regulations in Germany, these
problems can be eliminated
by using the Compactasphalt ®
method. The new method not
only cuts construction time by
half, helping to reduce motorway
congestion, it also brings
tangible technical benefits. It
makes use of the heat in the thick
binder layer that has just been laid
to gain time for the compaction
of the two upper layers. With
the conventional paving method,
the binder layer cools before the
wearing course is applied. In bad
weather this may lead to uneven
compaction.
GOOD COMPACTION of the
asphalt is crucial in roadbuilding,
but the rollers take time to do their
job. The cooling of the asphalt
during compaction reduces the
degree of compaction and with it
the durability of the road surface.
“By laying the binder and the
wearing course at the same time,
we apply a total of twelve centimetres
of asphalt,” explains Roland
Egervári, Product Specialist
Pavers at Dynapac. “Because the
applied asphalt is thicker, the useful
compaction time is extended
by a factor of at least seven.” This
is especially attractive for roadbuilding
in bad weather, when the
asphalt temperature falls rapidly.
BECAUSE THE TWO layers are
applied ‘hot-on-hot’, the Compactasphalt
® method also makes it
possible to reduce the thickness
of the uppermost layer to two
centimetres, as opposed to four
centimetres with the conventional
method. Since the wearing
course mix is particularly costly,
this means substantial savings for
the contractor and ultimately for
the taxpayer. Compared with the
conventional method, Compactasphalt
® also gives better bonding
between the individual layers,
helping to prevent crack formation
in the road surface.
ROAD SURFACES made of
compacted asphalt last longer.
On average, the loadbearing layer
of a road needs to be replaced
Text JOHANNES WENDLAND
after 40 to 50 years, the binder
layer after 15 to 25 years and
the wearing course after 10 to
15 years. So the wearing course
needs replacing at least once
during the normal service life of
a binder layer.
“This isn’t the case with
Compactasphalt®,” says Johan
Arnberg, Vice President Paving
& Recycling, Atlas Copco RCE
Division. “With this method we
can extend the service life of a
wearing course to match that
of the binder layer. So over the
entire lifecycle of a road, the
operator saves one re-laying
every 25 years.”
THE EVALUATION OF a
long-term trial with Compactasphalt
® on a stretch of road in the
USA, provides firm evidence of the
method’s benefits. The trial stretch,
built with a Dynapac paver,
was driven over continuously

“With Compactasphalt® we can extend the service life
of a wearing course to match that of the binder layer.”
Johan Arnberg
Vice President Paving & Recycling,
Atlas Copco RCE Division
by 60-tonne trucks, simulating an 18-year
service life in just two years. The trial stretch
showed not the slightest sign of fatigue in the
form of tracks or cracks.
“The long-term maintenance of a road is an
important cost factor for the owner,” says
Egervári. “A client who pays attention to
quality when a road is being built, and chooses
“A client who pays attention to quality and chooses
Compactasphalt® can look forward to decades of
trouble-free service.”
Roland Egervári
Product Specialist Pavers
Compactasphalt ®, can look forward to decades
of trouble-free service.”
BY THE END of 2007, Dynapac machines had
laid five million square metres of compacted
asphalt in Germany, China, Poland and Russia.
In Germany, the company has supplied
three large type F 300 CS road pavers for
Compactasphalt ®. This year, Dynapac will
the f300Cs / am300 moDular
paVer CaN Be useD Both for the
CompaCtasphalt ® methoD aND
CoNVeNtioNal paViNG.
rolaND eGerVÁri
be launching a modular extension of the triedand-tested
DF 145 CS paver. This will enable
smaller construction firms to switch to paving
with Compactasphalt ® at a favourable cost.
They only need to keep one paver, which can be
quickly adapted as the need arises. This brings
huge cost benefits, which firms can pass on to
their clients – giving them a further argument in
favour of Compactasphalt ®.
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many advantages
with the
Compactasphalt ®
moDular DesiGN – taNGiBle BeNefits eNViroNmeNtal BeNefits
FOR ROADBUILDING using the Compactasphalt ® method,
Dynapac offers the f300Cs high-performance paver. this
machine has two hopper modules to hold the materials for the
binder layer and the wearing course, and two screeds – a highdensity
screed for the binder layer and a normal screed for the
wearing course. The two screeds are adjusted relative to each
other to ensure that the thickness of the two layers is constant.
The maximum working width of the finisher is 13.25 metres.
DYNAPAC IS CURRENTLY working on a modular extension of the
Df 145 Cs series paver for working widths of 2.55 to 7.50 metres.
so it will soon be possible to deploy this widely used paver for both
the standard method and Compactasphalt ®, allowing contractors to
exploit their machines far more efficiently.
THE OPPORTUNITY to reduce the mix temperatures and
therefore reduce pollutant emissions.
BY REDUCING the mixed good temperature at 10 °C,
approx.0,23 l heating oil per one ton can be saved.
LONGER DURABILITY of the wearing course saves energy
costs concerning the production of mixed good.
REDUCED ROAD REPAIR and maintenance works.
NO BITUMEN EMULSION is needed (which is sprayed on the
binder layer in case of the conventional laying method)
AN ADDITIONAL REDUCTION of the asphalt binder course
from 10 cm to 8 cm (highway projects) is possible.
arNe eiChstaeDt
method
“We’re convinced of the
quality and also see the
clear cost and time
benefits of the method.”
Arne Eichstaedt
Head of Bunte Braunschweig

IMPROVED LAYING qUALITY
& HIGHER DURABILITY BY:
Creating a thicker asphalt layer during
laying and therefore an obviously significant
extension of the period of time available
for final compaction (t=k*d1,8) [1]
and the possibility to optimise the degree
of compaction, and positively influence
the deformation resistance.
t= time, k= constant, d= layer thickness
the available time for compaction
increases with the power of 1,8 of the
actual layer thickness. By increasing
the layer thickness from 4 cm to 12 cm,
the available time for compaction is
increased 7 times!
REDUCING THE INFLUENCE OF BAD
WEATHER on the compaction properties
of thin wearing courses by using the
asphalt binder’s residual heat.
JOHANN BUNTE Bauunternehmung
Gmbh & Co. kG is
a leading German construction
company based in papenburg.
since 2004, the company has
used the Compactasphalt®
method on numerous roadbuilding,
paving a total of 1.5
million square metres. the
company has a Dynapac f 300
Cs / am 300 modular paver
HIGH AND HOMOGENOUS DENSITY
through the complete layer depth
(wearing course and binder course)
EXCELLENT INTERLOCKING OF THE
COURSES (Cut power 37kN) Due to its
optimum bonding it will better withstand
high vertical forces. this is main criteria
for the long service life of the asphalt
pavement.
REDUCING THE APPEARANCE OF
RUTS AND CRACKS as it is possible to
take up higher vertical and horizontal forces
due to optimum degrees of compaction
and high layer adhesion (bonding
and tight interlocking).
BETTER DURABILITY can be expected
due to a feasible high deformation resis-
and also deploys the machine
on projects using the conventional
method. “for large construction
projects, Compactasphalt
® is the method of the
future,” says arne eichstaedt,
head of Bunte’s Braunschweig
office. “We’re convinced of the
quality and also see the clear
cost and time benefits of the
method.”
tance and good interlocking of the layer,
together with optimum air void content.
IT IS POSSIBLE TO EXTEND THE
PLANNED LIFETIME of the top layer,
to be close to the lifetime of the binder
course.
ECONOMIC OPTIMISATION of the
wearing course’s surface properties with
regard to skid resistance, brightness and
also the reduction of the course thickness.
COST REDUCTION
Due to a 50 % thickness reduction of the
expensive wearing course. No bitumen
emulsion is needed between the binder
and wearing course. Significant reduction
of paving times due to the simultaneous
laying of both courses.
“The
method of
the future”
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