Water ingress through unsealed joints in the carpark had caused erosion of the fill beneath. The weight of vehicles travelling over the unsupported joints further exasperated the problem by creating a pumping effect, resulting in liquefaction and displacement of the saturated fill material. Left untreated deterioration would have continued at an exponential rate causing the slabs to crack and break, ultimately necessitating full replacement at great cost and disruption to the client.
A site inspection by CPR identified significant voiding under the slabs and Slab Jacking, along with sealing of the joints, was proposed as the most effective and efficient solution.
During a 4 day occupation the CPR team injected over 1000kg of polyurethane resin, filling over 12,000 litres of void. The non-disruptive nature of the application allowed for the car park to remain in operation throughout the works.
The installation successfully levelled and stabilised the slabs; water ponding on the surface was also significantly reduced as storm water falls were returned to their intended levels.