Waterproofing of freshly cast substructure concrete.
Background
The new Broomfield Hospital in Chelmsford is the result of a £150m PFI investment whereby a public infrastructure project is funded with private capital.
Construction is over 5 levels and includes provision of an new Accident and Emergency Department plus state-of-the-art facilities for outpatients. Broomfield Hospital boasts a new maternity wing and surgical theatres with emergency access possible via a new helipad. In order to meet tight deadlines, fast-track methods of construction were adopted.
The Solution
To avoid the unwelcome delay involved in the wait for substructure concrete to reach its 28 day strength, waterproofing that could be applied to green concrete was required. After preparation by high pressure water jet, Monolevel FC was applied by bag rubbing technique to seal blow holes and other casting defects. This was followed with a spray application of Cementitious Coating 851 in two 1mm coats to provide high strength waterproofing to resist the impact of backfilling against the basement walls. The system is BBA certified and CE Marked to EN 1504-2 for Protection Against Ingress.
Client
Mid Essex Hospital Services, NHS Trust