Johannesburg - The solution for affordable road infrastructure development could lie in the use of nanotechnology, according to a paper presented at the 35th annual Southern African Transport Conference in Pretoria.
The cost of upgrading, maintaining and rehabilitating road infrastructure with limited funds makes it impossible for sub-Saharan Africa to become competitive in the world market, according to Professor Gerrit Jordaan of the University of Pretoria, a speaker at the conference.
The affordability of road infrastructure depends on the materials used, the environment in which the road will be built and the traffic that will be using the road, explained Professor James Maina of the department of civil engineering at the University of Pretoria.
Hauling materials to a construction site contributes hugely to costs, which planners try to minimise by getting materials closer to the site. But if there aren’t good quality materials near the site, another option is to modify poor quality materials for construction purposes. This is where nanotechnology comes in, he explained.
How to modify with nanotechnology
“Nanomaterial is really small; five nanometers are equivalent to 0.05mm,” explained Maina. The materials bind with the poor quality material which needs to be modified, and can then change the behaviour of the material.
For example, if the material is clay soil, it has a high affinity to water so when it absorbs water it expands, and when it dries out it contracts. Nanotechnology can make the soil water repellent. “Essentially, nanotechnology changes the properties to work for the construction process,” he said.
These nanotechnology-based products have been used successfully in many parts of the world, including India, the USA and in the West African region.
Why road infrastructure is critical for economic growth
“We need to have roads to enable mass movement of people and goods,” said Maina. Well-maintained road infrastructure ensures optimal speed of movement, opening up economic opportunities for people. Moving goods safely is also important as damaged goods translate into economic cost, he explained.
“For a country to be competitive globally, we need to reduce costs as much as possible. We need well maintained and well planned road infrastructure,” Maina said.
Some of the challenges to road infrastructure development in the Southern African Development Community region are linked to skills shortages as well as the harmonisation of policies and procedures and standards. “From one country to another, the methods, procedures and protocols are not the same. Harmonisation at a policy level will help.
“If we can work with each other to improve skills levels and harmonise standards and processes, this will lead to economic opportunities and growth,” he said.