Tarmac Precast Concrete is supplying precast bridge beams for use in tank covers on one of North West Water's bathing waters projects near Blackpool. It is managed by Bechtel and Bachy Soletanche as a Movement for Innovation demonstration project.
Bachy Soletanche and partner Tarmac Civil Engineering had originally planned an insitu concrete roof for the tanks which were built using diaphragm walling techniques. However, tank excavation would have had to be halted temporarily after 5m to provide a platform from which to build the roof.
Tarmac Precast Concrete came up with a scheme which involved the use of four 80t prestressed box beams and 42 Y7 standard bridge beams, measuring up to 26.5m long. With the Y beams spanning onto the box beams topped off with an insitu slab, the deck over the two 36m diameter structures will provide support for a car park.
Use of this method took a month off the construction programme and allowed the roof to be constructed after tank excavation was complete.
Contact Paul Whitham 01778 381000