Early in May, Nigeria’s Minister of Solid Minerals Development, Kayode Fayemi, mentioned that 80 percent of the materials used for road construction in the country are imported. Also, nearly N2 trillion ($1billion) is reportedly lost, annually, due to bad roads in the country. Considering the excessive amount of money spent on the importation of raw materials to construct asphalt roads and the current difficulty in accessing foreign exchange, will it be better for Nigeria to look towards cheaper alternatives for road construction?
Africa’s richest man, Aliko Dangote, recently closed a deal with the Nigerian government to construct concrete roads in Ogun, Lagos, Bauchi, Kogi and Kaduna States, beginning with the 26km Itori-Ibese cement road in Ogun State. The Itori-Ibese concrete road is part of his company’s corporate social responsibility to the people of the area while other cement roads will be built in exchange for income tax concessions.
Dangote’s argument about Nigerian roads has not changed, he has always opined that it is time for the country to replace its conventional asphalt roads with the cheaper and better alternative, concrete.
“We are pushing for Nigeria to do concrete roads. It is cheaper to do a concrete road that will last 50 years than to do a bitumen road. It will also help in eliminating corruption because if you go and build a bitumen road, it will have to be adequately maintained, unlike a concrete road that is very durable,” Dangote told pressmen.
“Our decision to introduce cement concrete roads in Nigeria is in line with what [is found] in other parts of the world. For instance, the famous Autobahn in Germany was constructed with concrete. The equally popular Marine Drive in Mumbai, India, which was built in 1939, is another example of a concrete road,” Dangote once said.
The business mogul has been quoted to have made those statements at various events, showing conviction in the durability of concrete roads.
Jennifer Picard, who specialises in asphalt and concrete construction, explained the differences between the two types of road construction in question on Quora. Her explanations align with the information gotten from a Nigerian Engineer who has a wealth of 13 years of experience in construction and pleaded anonymity. From an enlightening conversation, the following relative differences between concrete and asphalt road constructions were deduced:
Asphalt is a flexible pavement, which is used mainly for road construction because of its low construction cost and quick construction time. An asphalt pavement can be driven on the same day it is laid. However, asphalt requires regular maintenance to keep it in good working condition, where concrete does not. In fact, it is possible that overlay work or potholes are fixed on asphalt roads every 2 – 3 years whereas concrete roads can last decades without the need for repairs.
Concrete or cement road is a rigid pavement and is more expensive to construct because it is very labour-intensive but cheaper in the long run. This is because the cost of maintenance is nearer to zero than that of asphalt. Concrete is also used on areas that require a strong pavement surface, such as areas that garbage trucks drive over. It is also less susceptible to water and petroleum products, so it is used for drainage solutions (including gutters) and gas stations. Concrete roads last longer than asphalt roads with little or no repairs needed.
In a report obtained from the website of India’s Ministry of Rural Development, it shows the different cost estimations of constructing a kilometre of asphalt road and a concrete road. The evaluation also considered the maintenance cost and the Life-Cycle Cost Analysis. The report concluded that although the initial construction cost of a concrete pavement is higher than that of asphalt, the life-cycle cost of a concrete pavement is about 20-25 percent less than that of asphalt. Besides the life-cycle cost consideration, the report also recommended concrete roads for locations in heavy rainfall areas, and this fits in with the weather cycles in Nigeria.
Also, taking a quick look at the implication of constructing either of the two types of road on Nigeria’s local investment, concrete roads are a better option since its raw materials can easily be acquired locally, unlike asphalt roads where 80 percent of its construction materials need to be imported from elsewhere.
With the aforementioned, we can only recommend that the Nigerian government embrace the use of concrete in constructing roads since most Nigerian roads made of asphalt hardly last longer than 2-3 years before they are destroyed. Adopting this will only mean better roads for vehicles in Nigeria and less money spent on maintenance or repairs.