The Federal Government has faulted contractors for adopting the practice of mixing removed asphalt with laterite during road construction, describing it as a major factor behind the recurring failure of highways across the country.
Minister of Works, David Umahi, made this known during an inspection of the Abuja–Kaduna–Kano highway on Tuesday, according to the News Agency of Nigeria (NAN).
He cited Julius Berger’s earlier approach to the project as an example of the outdated method that compromises road quality and long-term durability.
Umahi explained that removing asphalt and blending it with fresh laterite weakens the road’s sub-base, as the new material does not compact or consolidate as effectively as the existing foundation that has settled over time. He said this poor compaction often leads to cracks and potholes even before construction is completed.
“When Julius Berger was doing the job, they removed the asphalt. They said they want to grind it with laterite It is not a good construction method because they brought new laterite on the road.
“There is what is called the Californian Bearing Ratio(CBR), which is the strength of the sub-base.
“So, when you remove this and you bring fresh laterite, the compaction, consolidation will not be as the one that has consolidated over the years.
“So, it is bound to fail, and that is why you see that what Julius Berger completed was beginning to see failures, even while they were still constructing,” Umahi said.
The minister further stated that the current administration is replacing this outdated practice with improved engineering standards and stronger materials, aimed at ensuring that new federal roads last up to 50 years without major repairs.
Furthermore, the NAN report noted that the Minister of State for Works, Bello Goronyo, revealed that about 285 pieces of equipment have been deployed along the Abuja–Kaduna corridor to ensure the timely completion of the project.