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Roadmac Surfacing has deployed three paving teams on this project.
the Harrismith bypass, Meissenheimer
says a 13,2 mm aggregate surfacing
seal with rubber bitumen is placed on
existing intersections and on the
on- and off-ramps. Gravel shoulders
will be built up over the full length of
the section.
Three farm accesses and the inter-
section at 42nd Hill (Verkykerskop) will
receive major upgrades to improve the
level of service for road users.
On the Harrismith bypass section,
sections of the southbound and
northbound lanes are also rehabili-
tated implementing a similar strategy
as on the Harrismith to Warden section
described above.
On the Harrismith bypass section,
a 40 mm thick A-R1 overlay is placed
over the entire cross-section of the
pavement, including the surfaced
shoulders of the road.
Surfacing, base and sub base
patching work is included in the reha-
bilitation measures for both sections
described above.
The Harrismith to Van Reenen
section also involves extensive road
rehabilitation works, and sees the
placement of a thicker overlay due
to the impact of higher truck traffic
volumes on the road infrastructure.
Meissenheimer says on the section
just south of Harrismith, the existing
gravel shoulders will be upgraded to
surfaced shoulders.
The top 150 mm is removed and
backfilled with imported virgin mate-
rial and the recycling is undertaken
to a depth of 300 mm and stabilised
with cement.
A 50 mm thick A-R1 overlay is
placed over the entire cross-section
of the pavement, including the
surfaced shoulders.
Rehabilitation
Meanwhile, the rehabilitation of the
pavement layers involves milling out to
a depth of 100 mm and recycling to rein-
state a C3 layer to a depth of 250 mm. The
100 mm milled out sections are filled with
BTB to original level.
Meissenheimer says pavement
rehabilitation differs from the other two
contracts. On the section closer to Van
Reenen, the bituminous pavement layer
is milled out to a depth of 120 mm and
removed. The C3 layer is 300 mm thick,
and the 120 mm milled out sections filled
with 80 mm of BTB and 40 mm of TRH8
with modified binder.
Extensive repairs are undertaken on
the slow lane and involve milling out 65
mm and filling with TRH8 with modified
binder. Here, a geotextile is applied after
the milling and again in the patch and
repair activities, before asphalt is placed.
The final surface treatment over the full
width sees the placement of a 22 mm
thick layer of UTFC. Shoulders are also
being reconstructed to tie into the raised
final road level.
One of the other challenges facing
the team has been working on this very
busy corridor which cater for total light
vehicle traffic of approximately 9 000
per day and approximately 5 600 heavy
vehicles a day.
Closures on the corridor to accommo-
date traffic in a safe unimpeded manner
are restricted and have to be carefully
managed. Roadmac Surfacing has
implemented a novel method of directing
traffic in the fast lanes while working
on the outer slow lanes allowing ample
space for safe and productive construc-
tion activities.
The low incident and accident count
on the three contracts since the start of
the project is a testament to the success
of the strategy.
Meissenheimer has reason to
be proud of the performance of the
team on yet another project that rein-
forces Raubex Group’s ‘blast to black-top’
capabilities.