Architect and Builder Magazine South Africa September/October 2014 | Page 28

Amsteele Systems Aid Fast Track
Programme on 102 Rivonia Road

A

fter a successful open tender
process, Amsteele Systems were
appointed, in late 2012, by Murray
and Roberts’s Construction (M&R) for
the design, supply and installation of the
post-tensioning works on the prestigious
102 Rivonia Road office block in Sandton,
Johannesburg. The building was developed by the Eris Property Group for main
tenant, Ernst & Young.
Initially, only Basements B7 to B1
were post-tensioned with a total area of
47,436m², with partial post tensioning
to the tower block levels, located mainly
along slab edges for deflection control,
due to the glass façades of the building.
The main contract was won by M&R
based on a fast track construction programme. Site occupation by M&R was in
June 2012, with the Ernst & Young tower
having to be completed by End October
2013 and the entire contract handed over
at the end of January 2014.

28

After the award of the contract, it
was proposed by Amsteele to fully posttension not only the basement slabs, but
all levels of the tower blocks, to speed
up the construction process in order to
give the finishing trades quicker access
to the completed floors. After due
consideration of all the benefits by the
professional team, as well as the main
contractor, the proposal was accepted, as
it was evident that this was the only way
that the extremely ambitious contract
programme could be met. This resulted in
an additional 40,405m² of post-tensioned
slabs, bringing the total area of PT slabs to
just under 90,000m².
The most challenging aspect of the
contracts was the fast track contract
programme. The site was operational 24
hours a day, seven days a week, for much
of the contract period; added to this were

the numerous work faces being worked
on simultaneously, extremely limited
laydown areas on site, the logistics of
getting the materials to site and straight
onto the deck being worked on. The
contract programme also only allowed a
two day period to fix both reinforcing and
post-tensioning for each pour, with each
having an average area of 600m².
Due to the complex architectural
design, each floor layout was different
to the preceding floor, which made
the design and detailing of the slabs
extremely challenging.
All challenges were overcome and the
contract was completed on schedule,
mainly due to excellent team work
between the professional team, main
contractor, Amsteele and its reinforcing
suppliers and also Amsteele’s in-house
design engineers.

Advertorial