Construction World February 2019

Once completed, Fourways Mall will be South Africa's second-largest retail development.

The precast system allowed for areas to be more quickly opened up to public parking.

but with precast there is no back-propping required. Another advantage of the precast system was that it allowed the project to run with fewer workers on site, an important benefit given the space constraints; instead, much of the concrete-related labour was effectively deployed off-site in the precast yards. In terms of project pace, the precast construction allowed work to begin on the finishes as early as the very day that a slab was laid, also allowing brickwork to begin earlier. In addition, it minimised environmental issues such as airborne dust and dirt underfoot, which could discourage shoppers. Concrete innovation The project’s precast approach involved large structures such as 10,5 metre beams, 8,75 metre slabs and 24 metre columns to be cast off-site, and then transported to site as required and efficiently installed. Prefabrication was done at two precast manufacturing yards serving the project – one in Laezonia and

environment as well as a tight timeline. This led to a 24-hour work cycle being adopted for six days a week for the past 24 months, with over 1 300 personnel and 21 tower cranes on site at its peak. Concrete work began in March 2016, structural work was completed by November 2018 and final mall completion is expected by April 2019. Advantages of precast Under these demanding conditions, the precast solution proved to be a key strategy enabling the construction to deal with the various challenges related to logistics, space and time. For instance, using precast elements meant fewer ready-mix concrete deliveries to site, which in turn eased the access to the road network around the shopping centre. It also meant that areas in the mall could be opened more quickly to public parking. Using conventional construction techniques, a back-propping system would need to be in place,

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CONSTRUCTION WORLD FEBRUARY 2019