Using geogrid to mechanically stabilise founding aggregate layers saved an estimated £2m on the A556 improvement scheme.
- £2m in construction costs saved
- 10,000 lorry movements avoided
- Time savings significant time savings compared with alternative solutions
Principal Contractor Costain needed a cost-effective solution to deal with highly variable and challenging ground, including thick layers of very soft clay, on sections of the A556 Knutsford to Bowden Improvement Scheme.
Tensar’s TriAx® geogrid was used stiffen the unbound capping layer on two sections of the new road, as an alternative to lime stabilisation and ‘dig and replace’ solutions. The cost-effective approach complied with Highways England design standards, exceeded bearing capacity requirements and had a beneficial effect on the programme.