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Tideway: Learning lessons from the Lee Tunnel secondary lining

Event organised by ICE

28 March 2019

This event has now ended

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In 2014 over 50,000m3 of fibre-reinforced concrete were used to line the 6.9km long Lee Tunnel.

During stormwater surge events, the tunnel routinely experiences internal pressures of up to 7.5bar, temporarily putting the lining into tension. To ensure 120yr design life, longitudinal joints were not permitted; the secondary lining had to be constructed as a full-round pour. This required both a highly technical concrete mix and sophisticated tunnel shuttering system.

The achieved concrete finish above tunnel knee level was superb; however the tunnel invert required extensive remedial work. Between 2019 and 2021 over 250,000m3 of concrete will be used to line the 25km long Tideway Tunnel.

This presentation explains how five key lessons from Lee Tunnel and are being implemented to ensure no remedial works are required, leaving a lasting legacy of superb homogenous concrete.

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Tideway is the company delivering the Thames Tideway Tunnel. It is owned by a consortium of investors, and more than two million pensioners have an indirect investment in Tideway through UK pension funds managed by those investors.

For more information please contact:

ICE Events Team