INDUSTRY INSIGHT AfriSam is supplying readymix concrete from its Umlaas Road operation, with its Pietermaritzburg facilities as a backup
AFRISAM SUPPLIES RAUBEX
in N3 upgrade
As part of extensive upgrades to one of South Africa’s most vital highways, JSE-listed contractor Raubex Construction is being supplied with construction material by AfriSam, including cement, readymix, aggregate and other quarry material.
R
aubex has been working on a 4 km stretch of the N3 highway, between Dardanelles and Lynnfield Park since January 2021, which will expand the current two-lane road to four lanes in each direction. The N3 between the port city of Durban and the country’s powerhouse of Johannesburg carries heavy traffic volumes that have only increased in recent decades. This project is part of government’s key Strategic Integrated Project focusing on the Durban-Free StateGauteng logistics and industrial corridor. It will improve access to Durban’s export and import facilities, and raise efficiency along this route. According to Abri Lubbe, contracts manager, Raubex, the road contract includes the widening
of four existing bridges and the construction of an entirely new road-over-road bridge structure at the Umlaas Road junction. This new twin-spine bridge over the R603 will allow easier access for both north- and south-bound N3 traffic heading for Richmond.
Bridges
“Work on widening the bridges at the Umlaas and Sunnyvale underpasses has been completed, as has the agricultural underpass,” says Lubbe. “This involved the construction of abutments, the application of precast beams, in situ decks, balustrades and end-blocks.” There is also one road-over-rail bridge that will be extended once the contraflow stage is reached, where traffic is diverted on to one side of the highway to give contractors full access to the other side. Piling for the twinspine bridge The project includes the widening of four existing bridges and the has been construction of an entirely new road-over-road bridge structure
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IMIESA May 2022
completed, allowing the foundations to progress on this lengthy aspect of the project; work began on this three-span structure in October 2021 and is due for completion by the end of 2023. Thys Greeff, construction manager, Raubex, explains that the contraflow will allow roadwork on the south-bound lanes to begin in earnest, which will include the complete revamp of the existing lanes.
Road construction “We are excavating the existing road by between 1 000 mm and 600 mm, and will fill this with blasted material from AfriSam,” says Greeff. “Depending on conditions, the next level may then comprise a 150 mm capping layer and a 300 mm G6 selected layer. This is followed by a 350 mm stabilised sub-base layer of crushed material.” AfriSam is providing its specialised roadstabilising cement, Roadstab Cement, which is being supplied in 50 kg bags to the Raubex subcontractor who spreads the cement on to the sub-base layer. By the end of the contract, around 180 000 bags will have been supplied, making up some 9 000 t of cement. The road layer will be completed with a 200 mm asphalt layer, comprising a 120 mm EME base, a 40 mm AP-1 interlayer, and a 40 mm bitumen-rubber gap-graded wearing course, says Greeff.
