Thames Tideway is a £5 billion infrastructure scheme to construct a 15-mile super sewer under the Thames to capture, store and carry tens of millions of tonnes of raw sewage that otherwise currently spills into the capital’s river every year.
The High-Modulus Solution
Working directly next to the Grade II* listed Vauxhall Bridge, we installed ArcelorMittal AZ50 steel sheet piles in pairs at 17.5m in length along with high-modulus universal columns to form an interconnecting cofferdam. The high-modulus element was required to allow for deep excavation works whilst coping with significant horizontal loadings created by tidal currents.
Utilising Ivor King’s Giken SCZ675 Double Crush in conjunction with our Giken F301, we believe this could perhaps be the first ever silently installed high-modulus wall, the sheet piles being hydraulically pressed-in. Two crawler cranes supported the installation; a 250 tonne crawler crane to suspend the crush auger string and a 160 tonne crawler crane supplying sheet piles to the Giken chuck. This was achieved by deployment of a two jack-up barges to overcome the natural tidal flow of the River Thames.
Protecting Infrastructure Under the Thames
In order to accommodate London Underground’s Infrastructure Protection Special Conditions and non-operational (engineering) hours stipulations, some overnight working was mandated. Given the close proximity of the Victoria line running parallel to Vauxhall Bridge below the Thames and nearby residential dwellings, a silent and vibration-free method of installation was deemed essential. The Giken solution was therefore specifically selected, limiting exposure to inhabitants of surrounding high-value properties with residents unaffected by noise and vibration during nocturnal hours piling works.
The Thames Tideway project will bolster London’s 150 year old sewerage system and is due for completion in 2024.
Ivor King has invested heavily in Giken Silent Piling technology in recent years, and are industry leaders in the use of Giken Supercrush technology.