Franki has developed a reputation for being able to handle demanding piling jobs, and few jobs could be more demanding than the R213 million Transnet-designed Berth 208 at the Port of Richards Bay. Although driven tube piles are commonly used in a marine environment, their installation is always challenging. But doing so from a floating barge with spud legs in often choppy seas requires expertise par excellence.
By his own refreshingly candid admission Ronnie Scheurenberg, specialist geotechnical engineer, is not good at multi-tasking. He says he becomes agitated when confronted with too many tasks at the same time. However, when perusing the formidable list of projects that he has successfully completed in his career, one wonders how one person could have achieved all of that in one lifetime. The answer, says this 25th recipient of the prestigious South African Geotechnical Medal for 2008, lies very simply in doggedly and persistently focusing on one job at a time. Behind Ronnie's ready smile and relaxed demeanour is a down-to-earth, kind and purpose-driven man who gets things done while living and enjoying life to the full.
The Huis River Pass has a long history and a geological beauty that was first opened to the public in 1897 by the Divisional Councils of Ladismith and Calitzdorp. As with most of South Africa's older mountain passes, the cut rock slopes have deteriorated with time, increasing the frequency of rockfalls and the need for road closures.
In the early 1960s, a new surfaced pass was designed by Kantey & Templer Consulting Engineers. Mr Basil Kantey, one of the founding members of the firm, played an integral part in the selection of four areas along the route where reinforced concrete retaining structures were constructed.
The section of National Road Route 1, Section 21, between the Lynnwood Road (Scientia) and Rigel Avenue interchanges on the eastern outskirts of Pretoria is being widened as part of the Gauteng Freeway Improvement Project (GFIP) at present being implemented by the South African National Roads Agency Limited (SANRAL).
For the widening in cuts the options were to trim the existing slopes in a thin sliver to the top of the cut or to construct a small retaining structure at the base. Space constraints and environmental considerations precluded the sliver option and it was decided that reinforcement with soil nails would be the most cost-effective option.
The Bapsfontein dolomite water compartment, located east of Pretoria on the Delmas road, is being dewatered at an alarming rate and is resulting in widespread instability in the area in the form of sinkholes, depressions or cracks. Many boreholes in the area are drying up and this is depriving inhabitants of their source of potable water. The question that needs to be answered is : Why are a few users in the area authorised to pump more water from the aquifer than its sustainable yield?
One of the components of the Medupi project is a coal-fired power station being constructed by Eskom at Lephalale, Limpopo province. The station has a planned total installed capacity of 4 800 MW, which will be delivered through six units with an individual capacity of 800 MW each. When completed, it will be the fourth-largest coal-fired power station in the world. Some 400 foundations, ranging in size from a few square metres to elements of hundreds of square metres, are at present being constructed as part of the project.
Given the correct soil conditions, open-hole auger piling cast in situ remains one of the simplest, quickest and cheapest piling methods available. This pile type is commonly used in South Africa as it is ideally suited to the partially saturated soils and relatively shallow rock encountered over much of the country. These advantages are, however, diminished by the uncertainties inherent in auger piles with respect to the transfer of load from the base of the pile to the in situ soil or rock.
Maccaferri Southern Africa has maintained its place as a leading solution provider in the broad field of civil and environmental engineering. The range of solutions includes : mass gravity gabion retaining walls, reinforced soil embankments, slope stabilisation, erosion control, bank protection, channel lining, scour protection, wetland rehabilitation, rockfall protection and basal reinforcement.
Geotechnical expertise has been put to the test by the substantial capacity enhancement of Konkola mine through the Konkola Deep Mining project near Chillilabombwe in Zambia by Konkola Copper Mines (KCM) Plc. Innovative solutions had to be applied while sinking a new No 4 Shaft from surface through subsoil (lateritic) and incompetent rock to a considerable depth.
The geotechnical conditions of a site often have a large influence on the final design and position of a shaft, or of any structure for that matter. This article examines the methods used to investigate and acquire information for the assessment of the ground conditions and presents two selected case studies. An understanding of the site's geology and geomorphology is of great importance to the geotechnical assessment.
This article discusses the application of the information currently available on the land maps and soil types for South Africa and their accompanying material data, originally compiled to provide information for agricultural purposes, as a costeffective preliminary indicator of the common problem soils for civil engineers. Such information is extremely useful for the planning, feasibility and preliminary design stages of road construction and other civil engineering projects.
As a final year student at the University of Pretoria I had the privilege last year to write a paper for the 5th South African Young Geotechnical Engineers Conference (YGEC ). The conference took place at the Camelot Conference Centre in Hillcrest, Durban, from 20 to 22 August 2008.