Floating Pile Gate

The Challenge
Install a new sheet pile retaining wall at 325.5m in length, constructed using 219 No pairs of AZ28-750 sheet piles in the fast-flowing tidal River Thames Lower Reaches.

Two methods undertaken: the western section of the sheet pile wall was installed using a 250T crawler crane positioned on an existing jetty. The Eastern section of the sheet piled wall was installed using a 320T crawler crane positioned on a floating crane barge. AZ28 sheets were installed using a bespoke floating pile gate system.

Design
Graham commissioned Dutch Maritime Consultants Temporary Works Design (TWD) to design and develop the floating pile prototype gate covering stability calculations and environmental conditions including wind generated waves and vessel generated waves. Manufacture and fabrication of the floating gate was undertaken in-house by Graham.

Results
Safety: The floating gate offered a safe and level working platform for marine operatives to work on whilst pitching and driving piles in the marine environment.

Increased productivity: Driven sheet pile productivity was significantly increased as using the floating gate allowed installation activities both during high and low tides.