Roads carry the economy, and the pavement beneath the traffic decides how long they last. Two main types are used in Nigeria: flexible pavements surfaced with asphalt, and rigid pavements made of concrete. Each has strengths, and the right choice depends on traffic, ground conditions, budget and how the road will be maintained. This guide explains how they differ so owners, communities and contractors can make better decisions.
Two Ways to Build a Road
Asphalt (flexible) pavement
An asphalt road is built in layers. The subgrade, the natural ground, is prepared and compacted; a granular base and sub-base spread the load; and one or more layers of asphalt form the wearing surface. The structure is called flexible because it bends slightly under load and spreads the stress down through the layers to the ground.
Concrete (rigid) pavement
A concrete road uses a slab of reinforced or plain concrete, laid over a prepared base. The slab is stiff and spreads loads over a wide area. Some designs use joints at regular intervals, while continuously reinforced concrete pavement (CRCP) uses a continuous mat of steel to control cracking and needs fewer joints. Reports on the Benin–Sapele–Warri road, for example, describe sections being built with continuous reinforced concrete pavement.
How They Compare
- Initial cost: asphalt is usually lower; concrete is usually higher.
- Construction speed: asphalt is fast and opens to traffic quickly; concrete needs curing time before traffic.
- Repair: asphalt is easy to patch and resurface; concrete repairs are more specialised.
- Behaviour in heat: asphalt can soften and rut under heavy, slow traffic; concrete holds its shape well.
- Behaviour with standing water: asphalt is vulnerable if drainage is poor; concrete is generally more resistant, but still needs good drainage.
- Maintenance: asphalt needs regular resurfacing and crack sealing; concrete needs less frequent work, but joints and cracks still need attention.
Cost comparisons should look at the life of the road, not only the construction price. A more expensive pavement that needs little maintenance can be cheaper over decades, while a cheaper pavement that is well maintained can also give excellent value.
What Decides the Right Choice
Traffic loads
Heavy trucks, tankers and buses concentrate large loads. Roads on freight corridors, around ports, industrial areas and processing plants often justify a stronger, longer-life pavement, while light residential and access roads are well served by asphalt.
Ground conditions
Soft or poorly drained soils, common in parts of the Niger Delta, put any pavement under stress. Whatever surface is chosen, the subgrade must be investigated, treated where necessary and drained. In firmer laterite areas, such as much of Edo State, well-compacted bases perform very well.
Drainage
Water is the main enemy of roads. Side drains, culverts, camber and sealed joints keep water out of the pavement structure. Many road failures blamed on the surface are really drainage failures.
Budget and maintenance capacity
Asphalt is quicker and cheaper to build, but it must be maintained. A concrete road costs more at the start but may need less routine work. The best pavement is the one that the owner can realistically afford to build and keep in good condition.
Construction Quality Matters More Than the Label
Whether asphalt or concrete, quality in construction decides how long the road lasts. For an asphalt road, that means careful subgrade preparation and compaction, the right layer thicknesses, asphalt placed at the correct temperature and rolled to the specified density, and clean, well-formed joints. For concrete, it means correct mix design, reinforcement placement, joint detailing and curing. This is where experienced crews and well-maintained equipment make the difference: graders, vibratory rollers, compactors and an asphalt paver all contribute to a smooth, durable result.
Other Surfaces: Interlock Paving and Beyond
Asphalt and concrete are not the only options. Interlocking concrete paving blocks are widely used for terminals, car parks, estate roads, pedestrian areas and forecourts. They are laid over a compacted base, can be lifted and re-laid when services need access, and give a durable, attractive surface for lower-speed, high-footfall areas. Choosing the right surface for each part of a site, heavy-duty pavement where trucks run and paving where people walk, gives better value than using one surface everywhere.
Maintenance: What Each Pavement Needs
Every road needs maintenance, and planning for it is part of choosing the pavement. Asphalt roads benefit from routine inspection, prompt sealing of cracks, patching of potholes before they spread, and periodic resurfacing. Left alone, small cracks let water into the base and the damage multiplies quickly. Concrete roads need their joints kept sealed, cracks monitored, and any faulty slabs repaired, which calls for specialist methods. In both cases, keeping drains clear and shoulders in good shape protects the structure. Owners who set aside a maintenance budget from the start get far more life from their roads.
Common Reasons Roads Fail Early
- Poor drainage that lets water soften the base and subgrade
- Inadequate compaction of the subgrade or base layers
- Pavement thickness designed for lighter traffic than the road actually carries
- Asphalt laid in wet conditions or at the wrong temperature
- Skipped or rushed curing on concrete
- No maintenance until the damage is severe
Almost all of these are avoidable with good design, supervision and workmanship.
Examples from Pekuric's Work
Pekuric constructed a 3.4 km asphalt road through the Obaretin corridor in Ikpoba-Okha, Edo State; see the project page. On the Benin Central Bus Terminal, our scope included interlock paving and pedestrian walkways; see the project page. Road construction is one of our core services, supported by an owned fleet of graders, rollers, compactors and an asphalt paver, which lets us mobilise quickly and control quality on site.
Questions to Ask Before You Choose
- What traffic, including heavy vehicles, will use the road in the next 20 years?
- What does the site investigation say about the subgrade and the ground water?
- How will water be drained away from the road?
- What maintenance budget and capacity will the owner have?
- Has the contractor built similar roads, and does it own the equipment needed?
Get Advice for Your Road
Pekuric builds roads for government, corporate and private clients in Edo State, Delta State, Rivers State, Abuja and across Nigeria. Learn more about our road construction services, or contact us to discuss your road project.
