TECHNOLOGY
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Ports are susceptible to water damage, as their concrete foundations and columns, as a rule, are completely unprotected.
Spray-applied waterproofing membranes are tested to last 30 – 50 years and, while other maintenance may have to be done, the underlying waterproof membrane would not have to be looked at during that time.
Ports have a special problem
In the past 30 years, major technical advances in cementitious coating technology have enabled longer service-life solutions to be implemented for ports, tunnels, bridges, and power stations— any infrastructure made from concrete and bricks that, due to its porous structure, is sensitive to damp. Water can cause cracks and erosion of concrete surfaces, reducing its anticipated service life. When the Condeep platforms were built in the 1970s and 1980s to extract North Sea oil, their concrete bases were protected with an advanced silicate technology. Those platforms remain standing today, undamaged some 40 years later, despite an extremely exposed environment. However, the concrete foundations and columns in many of today’ s ports, as a
22- CEC June 2018
“ The challenge for the South African industry is that globally, we are at the leading edge as part of a larger fraternity, but as a country, we are financially constrained. Local spend is below international expenditure trends.”
Dr Kevin Gast, Thusanang Gast
rule, are completely unprotected and consequently have extensive damage. In water reservoirs and dams, problems also arise with leakage and erosion caused by friction in water. Silicate technology, such as Innerseal concrete waterproofing, seals and hardens in depth.
Mine seepage prevention In a mining-intensive economy such as South Africa, a particular risk is that of seepage of toxic mine water into municipal waterways. Increased emphasis on protection of the environment means that the problem of acid mine drainage has become an important priority. Use of Sika’ s Sikadur-Combiflex SG system ensures the durability of mine water reclamation plant in grimy coal-mining areas such as Middelburg, Mpumalanga, as well as the provision of millions of litres of potable water to local communities. In one project, the Sikadur- Combiflex SG system was used to seal all construction and expansion joints within the water-retaining structures, including all water tanks and clarifiers. According to Sika’ s website, when fixed to a joint, the Sikadur-Combiflex SG system allows for irregular and high movement in more than one direction while still maintaining a high-quality seal. The CSIR is researching alternative materials that involve a smaller carbon footprint in their manufacture and are acid resistant. Thus, clay mineral kaolinite materials can be used to make concrete blocks, bricks, and pavers that are stronger, more durable, yet cheaper and with lower carbon emissions.
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