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CONSTRUCTION WORLD
AUGUST
2016
Significant
ROAD BUILDING
capabilities
PROJECTS AND CONTRACTS
Five member companies work
simultaneously on the three works
packages making up the contracts,
which were awarded to Roadmac
Surfacing by N3 Toll Concession (RF) Proprie-
tary Limited (N3TC).
Roadmac Surfacing established on site in
January 2015 to start tackling the rehabilita-
tion of the stretch from Warden to Harrismith
and the Harrismith bypass. The company
started working on the third component
of the project, namely Harrismith to Van
Reenen’s Pass, in August last year.
Andre Meissenheimer, contracts man-
ager at Roadmac Surfacing, says the project
involves a heavy rehabilitation of the existing
road infrastructure.
One of the biggest challenges is the strict
riding quality requirements of sections of
the rehabilitated infrastructure. It calls for a
high performance asphalt mix which is being
produced by National Asphalt, a member
company of Raubex Group.
“There is limited margin for error on
the programme. Both companies, Roadmac
Surfacing and National Asphalt, have to be
very proactive and monitor materials produc-
tion every day,” says Meissenheimer.
He says the asphalt being produced for
this contract has a five year guarantee, and is
being batched at two plants built by Comar.
The plants were supplied by subsidiary
B&E International, the contract crushing
arm of the Group that also specialises in
large processing plants. National Asphalt is
batching 800 t of material a day to meet the
production requirements.
Harrismith to Warden
Roadmac Surfacing will place 40 000 t of
bitumen treated base (BTB), 2 000 t of
coarse graded asphalt mix as per TRH8
(TRH8) and 116 000 t of rubber bitumen
asphalt (A-R1) for the Harrismith to Warden
section. The Harrismith to Van Reenen
section will consume 6 000 t of BTB,
17 000 t of TRH8, 24 000 t of ultra thin friction
course (UTFC) and 13 500 t of A-R1, while the
Harrismith bypass section requires 6 000 t of
BTB and 12 500 t of A-R1.
The company has deployed three paving
teams on this project. Equipment deployed
by each team includes a paver and Shuttle
Buggy, a special material transfer vehicle, a
three drum roller, a double drum vibratory
roller and two pneumatic rollers.
Roadmac Surfacing is joined on the
project by Raubex Group’s Milling Techniks,
which has deployed two recycling and milling
units on the projects.
Work on the 50 km long stretch from
Harrismith to Warden includes the recon-
struction of the truck lanes (slow lane) by
recycling the existing pavement materials.
The in situ base and sub base layers are
pulverised and pre-shaped, before receiving
the lime and cement stabilising agents,
which are spread by hand. The sub base layer
is processed with a recycling unit to a depth
of 300 mm to reinstate a C3 quality layer.
A 100 mm wide, 60 mm deep key is cut
into the pavement of the existing fast lane
and materials removed. This creates a keyed
joint between the adjacent fast and slow lane
pavement structures.
Meissenheimer says that a 60 mm
bituminous base with modified binder is then
placed to reinstate the pavement to the orig-
inal level. The full width of the pavement is
then finished off with a 40 mm A-R1 overlay.
On the Harrismith to Warden stretch and
Rehabilitation of sections
of the strategic N3
corridor connecting
Gauteng to the Port of
Durban again highlight the
significant road building
capabilities housed within
the Raubex Group.
>
One of the biggest challenges is the strict riding quality requirements of sections of the
rehabilitated infrastructure.
“There is limited margin for error on the programme.
Both companies, Roadmac Surfacing and National
Asphalt, have to be very proactive and monitor materials
production every day.”
Road Techniks is just one of a number of
Raubex companies operating on this project.