The current reconstruction of two dilapidated highways with concrete technology, instead of conventional asphalt/bitumen, is generating interests among NigeriansâDayo Ayeyemi, Reporter-New Telegraph Online News.
Nigeria has about 195,000 kilometers-(km) of road network (121,167 mi)âabout 32,000 km (19,884 mi) federal roads and 31,000km (19,265 mi) state roads. Out of the entire road network, only about 60,000 km (37,282.5 mi) are paved with asphalt/bitumen while about 135,000 km (83,885 mi) are “un-tarred”/unpaved.
Nigerian citizensâ concerns over what the Nigerian government is doing to ensure that the entire nationâs road networks are safe and easily mobile, and not just âtarredâ for convenience, has become paramount. Among stakeholders in the developed environment, adequate road infrastructure is critical to economic growth, as road transportation accounts for about 90% of freight and passenger movements in the country. According to experts, Nigeria loses about N197 billion ($1billion US) annually due to poor condition of roads in the country.
Seeking alternative pavements to the usual asphalt/bitumen for roads, stakeholders are mulling support for concrete roads, which they say have proven to be more durable and easier to maintain. Dangote Group, through its subsidiary, AG Dangote Engineering, has recently blazed the trail in this regard with the construction of 28 km (17.4 mi) of the Itoti-Ibeshe Road in the Ewekoro Local Government Area, Ogun State. Consequently, there have been calls for more investment in concrete roads, which professionals said could save the government several billion naira due to their longevity and low-maintenance qualities.
CONCRETE ROADS:
To further convince Nigerians and the Nigerian government, in August 2017, the Dangote Groupâs Corporate Social Responsibility (CSR), in collaboration with Flour Mills Nigeria Limited and the Nigerian Port Authority (NPA), kick-started the reconstruction of 2 km (1.25 mi) of Apapa-Wharf road in Lagos using concrete. The group also commenced the reconstruction of 43 kms (26.7 mi) of the Obajana-Kabba road in Kogi State as well (at a cost of N4.3 billion).
Mr. Olatunbosun KalejaiyeIn, Project Director-AG-Dangote Construction Company Limited, said in less than one year, the reconstruction of the 2 km of the Lagosâs Apapa-Wharf had attained 75% completion, while 29km of 43 km (18 of 26.7 mi) of Kogi Stateâs Obajana-Kabba road has been completed. KalejaiyeIn added that both road projects would be delivered by July 2018 and December 2018 respectively. Tunde Jimoh and Akhimienho Emmanuel, Project Managers of both projects, said the infrastructure would last 60 years upon completion.
As he explained the technical details of the road construction, Jimoh said, âWe have many layersâ
1) the concrete pavement 25.5-30.5 cm thick (10-12 in)
2) a sub-grade stabilized with hardcore
3) an impermeable layer of sand cement
4) the sub-soil drainage that drains out the water underneath the sand cement, plus
5) the stone base well compacted.â
EXPERTS’ VIEWS:
With these practical examples, experts from further-developed environments favor the use of concrete for the nationâs highways due to its durability and ease of maintenance. Victor Oyenuga, Past President-Nigerian Institute of Structural Engineers, stated that the use of concrete for road pavement has come to stay in the country. Unlike bitumen, he said there is evidence abound overseas that concrete roads are more durable, easy to maintain, non-slippery, and offer less tractive resistanceâproviding good visibility for traffic during night hours.
He said: âConcrete roads last longer, are low in maintenance cost, and difficult to crack. Although it requires special machinery to lay, I recommend it for Nigeriaâs roads.â
For the entire New Telegraph article titled âRoad construction: Cement concrete to the rescue”, please go to: https://newtelegraphonline.com/2018/07/road-construction-cement-concrete-to-the-rescue/
For the ISCP November ‘Nigerian concrete pavement’ article, please go to: https://www.concretepavements.org/2017/11/13/innovating-road-construction-in-africa/