Studies recently completed by JG Afrika have informed the design of the rehabilitation of a strategic road that connects Tin Can Island Port to major commercial centres in Lagos State, Nigeria.
The existing access road from Tin Can Island and the six-lane expressway that connects Apapa Wharf, one of Nigeria’s major commercial centres, to Oworonshoki was built as early as the 1970s and has since fallen into a serious state of disrepair.
Rehabilitation of the roads as part of a public-private partnership was first mooted by AG Dangote Construction, and the proposal was favourably received by the Federal Ministry of Power Works and Housing.
JG Afrika proposed a continuously-reinforced concrete pavement (CRCP) design to better cope with the growing number of heavy commercial vehicles travelling between Apapa Wharf and Oworonshoki every day.
The concrete pavement design expertise of Ane’ Cromhout, pavement engineer with the JG Afrika team, formed the basis of the recommendations to use CRCP.
It replaces the initial suggestion of using a conventional jointed concrete pavement that would ultimately develop slab tilting and stepping on the extremely soft subgrade material encountered along sections of the existing road from Apapa to Oworonshoki.
Dangote Industries can be credited for introducing concrete pavements to the West African country.
Meanwhile, its construction arm has also invested heavily into the equipment required to construct these pavements. These include a concrete paver to significantly accelerate construction times and a state-of-the-art road recycler that will be able to easily convert the base layers into a cement-treated base on site.
Dr. Emile Horak, who led the JG Afrika team that undertook the pavement evaluation, previously played an instrumental role in assisting the contractor introduce in-situ recycling equipment to the West African country.
“Using this technology, combined with the concrete paver, the contractor will be able to complete the extensive rehabilitation required in a significantly shorter period than is possible constructing a conventional asphalt pavement. This is a major advantage considering that the contractor will be working in an extremely built-up area. The onerous process of having to relocate people and structures, in addition to the inconvenience caused by prolonged construction activities, were among the chief reasons for the Nigerian authorities ultimately delaying the rehabilitation of the road over the years,” Dr. Horak says.
JG Afrika was appointed by the contractor to undertake the pavement evaluation in 2018, and these critical insights have been incorporated into the final rehabilitation design by Yolas Consulting. The Nigerian engineering consultancy is working on behalf of AG Dangote Construction.
A detailed assessment of the condition of the road pavements and a geotechnical investigation of material used in the existing road were undertaken as part of the project. In addition, JG Afrika undertook an extensive investigation of all available construction materials to build the road and structures.
Dr. Horak says that the recommendations made by JG Afrika were well received by the contractor and he anticipates work to commence imminently on the rehabilitation this critical road infrastructure.