Construction World Septemer 2017

Some of the existing live services which required special attention to maintain supply to neighbours.

“The varying ground conditions with old rock-filled docks and piers and the high- water table as described above present a significant challenge.”

is effected rapidly using the ‘Down The Hole Hammer’ (DTH) percussion drilling technique. As with CFA, noise levels are low and vibration limited. Schultz says that the foundation piles were designed with flexibility in mind to meet the varying and sometimes unpredictable ground conditions. Three pile types were used: the Franki Driven Cast-in-Situ piles, Temporary Cased Augers and Oscillator piles with individual load bearing capacities from 2 300 kN to 10 000 kN. To say that the Franki Pile is the most well-known piling system in southern Africa is certainly no

exaggeration. Developed circa 70 years ago it is still one of the most popular pile types in this region. Its main feature is the large base formed at the toe of the pile and, in forming it, the end-bearing area is considerably increased. It is generally a very economical system, has an extensive range of pile sizes and, like the other piling systems used on The Yacht Club site, its noise levels are relatively low. Another significant challenge on this project was the very demanding schedule. “This meant that the works not only had to be very carefully planned but also executed to perfection,” says Schultz. He explains that AMDEC required a phased handover to the main building contractor so that the critical- path tower cores and basement sections could be started whilst Franki were still busy on site. “We started operations during the latter half of 2016 and completed everything on time and within budget by mid-March 2017,” he says. Schultz paid tribute to Franki’s client, AMDEC, and to bulk earthworks contractor, Ross Demolition. “To have successfully completed this project on time we needed it to run like clockwork. This was facilitated by these two professional companies which pulled out all the stops to ensure that we could do it,” Schultz concluded. 

Installation of Franki Piles.

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CONSTRUCTION WORLD SEPTEMBER 2017