Gauteng Piling, a leading piling contractor, successfully completed the supply and installation of piling for a river bridge that will be constructed as part of the upgrade of road infrastructure between the University of Venda’s (Univen) New Punda Maria gate and Punda Maria Road (R524).
Part of Univen’s ongoing investment into upgrading infrastructure to attract more students, the new 1,6km road and river bridge will improve access to the university.
Subcontracted to principal contractor, Tainama Civils, Gauteng Piling mobilised to site on 25 October 2023 to start supplying and installing the 750mm auger piles. On 4 December, the contractor’s state-of-the-art piling machine on site was converted to install the sheet piling, which was completed at the end of January 2024.
The project again provided Gauteng Piling the opportunity to demonstrate the extent of its capabilities. This is considering the challenging nature of the contract with its unpredictable soil conditions, consisting of very soft and very hard clayey material; a perched water table; extensive hard rock; and unforeseen boulders.
Lethabo Mashala, Contracts Manager of Gauteng Piling, and her team successfully navigated all obstacles to finalise the geotechnical work by the contractual completion date.
Mashala attributes much of the project success to interdisciplinary collaboration which facilitates innovative and creative thinking. This is in addition to Gauteng Piling’s extensive skills and experience which enable the company to deploy sophisticated techniques.
“A case in point was the use of 10m temporary casings to mitigate the risk of collapses and the flow of water into the holes, a technique that can only be undertaken by a proficient and seasoned piling contractor. Temporary casings are used to retain the sides of boreholes long enough for concrete to be placed. Once it has reached a level sufficient to withstand ground and groundwater pressures, the temporary casings are removed while additional concrete is placed to maintain the pressure balance,” Mashala says.
Certainly, rigorous monitoring throughout the duration of the contract also ensured that potential problems were identified and resolved quickly so that the project progressed according to schedule.
A total of 12 auger piles were installed. Reinforcing cages, comprising 10y25 longitudinal bars, each 12m in length with a y10 outer spiral at a150mm pitch, were placed over the full length of the piles and the four 65mm-diameter ID steel tubes inside the augered holes. These ducts were used to undertake integrity testing of the 30 Mpa concrete placed in the piles.
As is the case with all its contracts, Gauteng Piling adhered to strict health and safety specifications and requirements throughout the project duration.
Mashala is also proud of the jobs that the project created for general and unskilled workers who reside in Thohoyandou.
“We have again demonstrated the importance of dealing with an experienced piling contractor with a comprehensive profile of completed projects. Our workmanship will play a critical role in the construction of a robust bridge that continues to add value over its lifecycle,” Mashala concludes.
