Case Study: ASDA Steel Intensive Sheet Pile Basement, Birkenhead, Liverpool

ASDA Steel Intensive Sheet Pile Basement, Birkenhead, Liverpool

Contract No:C829
Client:R.G. Group
Location:Birkenhead, Liverpool
Value:Approximately £335,000.00
Summary:Design, supply, and installation of steel sheet piles to form a permanent sheet pile basement retaining wall providing both temporary and permanent lateral earth retention for a car park to a new town centre store. The sheet piles permitted the excavation and construction of the proposed underground car park structure whilst also providing permanent support for the superstructure loads from the superstore above. The clutches were sealed by welding to give a watertight retaining wall.

Sheet Piling UK Limited were employed by Principal Contractor R.G. Group to design, supply and install a watertight sheet pile retaining wall to form a sheet pile basement car park to the proposed new Asda store in Birkenhead, Liverpool.

Working closely with the lead Consulting Engineer and R.G Group from an early stage, Sheet Piling UK Limited were able to provide a “Value Engineering” solution which was delivered within budget and provided significant programme savings.

The 460 no. NSP.3W sheet piles at 6.0 to 8.0m long were installed using a Giken Piling “Silent Piling and Vibration Free” hydraulic pile press due to the close proximity of the existing pedestrianised shopping centre and adjacent basement structures.

The general soil profile consisted of Made ground over stiff alluvial Clays. The retaining wall design was, in part, subject to Highways Agency Approval. Due to the depths of the cellular steel beams supporting the ground floor construction, the steel sheet piles were installed within a lead trench to enable the sheet piles to be installed to final head levels eliminating the need trim the piles at a later date and hence reducing unnecessary wastage.

The design requirement for the sheet piles to support vertical loads form the building above was verified by carrying out non-destructive dynamic pile testing on “test Piles” using the pile driving analyser and CAPWAP calculation.

The clutches of the sheet piles were welded to give a fully watertight retaining wall and a concrete capping beam was constructed by the Principal Contractor.