landmark geotechnical projects

Stefanutti Stocks Geotechnical undertook the lateral support, bulk earthworks and dynamic compaction contract for the Lakeside Towers development in West Avenue, Centurion. The geotechnical project for Exxaro’s new head office was completed at the end of July 2017.

What made this project particularly challenging is the fact that Centurion is classified as a high-risk dolomite area. It has a high inherent risk of very large size sinkhole and doline formation, which required the implementation of a dolomite risk management strategy, including the appointment for a dolomite risk manager to the project. More information on the project is available here.

Stefanutti Stocks Geotechnical successfully completed the design and supply contract for the deep foundations to the Kazerne Transit-Oriented Development project in Newtown, Johannesburg. This comprised of 25 039m³ of bulk earthworks, 1 750m² of permanent lateral support, 440 structural piles and temporary traffic diversion.

The piling work comprised of 242 Continuous Flight Auger (CFA) piles, installed up to 23 metres deep; 133 polymer-technology drilled piles installed to a depth of up to 30 metres deep; as well as 65 Auger Cast In Situ (ACIS) Soldier piles installed to depths of up to nine metres. More information on the project is available here.

Stefanutti Stocks Geotechnical is applying its wealth of experience to the construction of deep piled foundations in Namibia, where it is installing 76 permanently cased, raked oscillator piles for river bridges. These bridges are on the outskirts of Swakopmund and form part of the upgrade of the old salt road to a new highway between Swakopmund and Walvis Bay.
The geology in the Namibian desert consists of sand, calcite, granite and boulders, and all the deep pile foundations will have their sockets founded into the calcite and granite.

The required plant and equipment was mobilised from South Africa and included Stefanutti Stocks Geotechnical’s Bauer BG28 (with a BV1500 HD oscillator) and a Kobelco Crawler Crane. More information on the project is available here.

Stefanutti Stocks Geotechnical recently completed the contract for the construction of deep pile foundations to a road-over-rail bridge for client Power Construction on the 3,36-kilometre MR559 on the outskirts of Saldanha Bay. The project entailed the construction of a total of 78 temporary cased piles (1 080mm diameter) up to a depth of 35 metres. The bridge’s two abutments (west and east) respectively required 34 and 36 piles, with a centre pier requiring eight piles.

Thirty-five of the overall total piles had a rake of 1:6. A further challenge to the project saw 36 of the piles with a 9.5 degree rake (1:6 rake) meaning that a 35-metre long pile deviated 5.8-metres away top to toe from the original pegged platform position to the vertical pile head. The setting out, drilling and concreting of these piles therefore required special skills, in order to meet the contract specifications and tolerances. More information on the project is available here.