The Civil Engineering Contractor February 2019 | Page 21

ON SITE
The major complexity was the busy CBD location.
out that the previous owner had
constructed the parking lot over a
previous building, the foundations of
which were still in place. “Initially,
it was a four-week programme, but
the 1 000m 3 put big pressure on that
timeline, pushing it out to six weeks.
However, we dealt with it speedily
and over the course of the project
pulled back those two weeks.”
Bamboo Rock won significant ‘green
points’ for the developer as it had
established relations with a concrete
recycler nearby in Isando, and the
1 900m 3 of waste was taken there
and recycled. “Recycled waste can be
a lot cheaper than virgin material.
The materials supplier company only
accepts clean building rubble, the full
amount of which it normally blends
into its mixes, which has in every case
subsequently been approved by the
engineer,” explains Chapman.
For the cut material, Chapman says
his company has an agreement with a
property developer to use the 7 500m 3
spoil for its building platforms.
“The complexities of the site were
all normal for such a project, with
logistics being a challenge considering
it is a built-up CBD site. Loading and
www.civilsonline.co.za
offloading of equipment has been a
challenge, especially large machines
due to the limited access to the site. A
temporary access was given next to the
Jewel City entrance,” says the Bamboo
Rock site manager, Daryn Searle.
Equipment on site included a D5
bulldozer and a CAT 20t excavator
for the loading of material. Thirty-
tonne hydraulic hammers were used
to break up the concrete. During the
height of work, there were fourteen
10m 3 Mercedes trucks on site, a
grader, a roller, and a water truck for
dust suppression.
Scope of work: The
full development
Pautz explains the entirety of the
development as encompassing
six city blocks, five of which had
pre-existing buildings on and were
previously used in the diamond and
precious metal trade industry. The
sixth one, the site of major civils
work, was previously an open parking
lot (which had also had a building on
and consequently had considerable
foundations requiring demolition).
“Our plan is to redevelop the five existing
buildings and build a new residential
“Before we got onto
site, there was a parking
lot here. This entailed
uplifting paving and
curbing and its removal
off site. There was a small
excavation of a box cut.”
build on Block 6. Block 1 is a residential
conversion where we will be adding 550
units; Block 2 is a two-storey commercial
building; Block 3 for now is a future phase
— the Diamond Trade Regulator and a
company are still in there until January
2020, after which we’ll do a second-
phase redevelopment; Block 4 will be
used primarily for parking and retail; and
Block 5 is a new commercial conversion
for typical Grade A-type tenants and call
centres. On all those blocks, there’s retail
on the ground floor, as well as parking.
Our plan is to fully pedestrianise Fox
Street, for which we have agreement from
Johannesburg Roads Authority (JRA) and
the City. Pedestrianisation will involve
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