The presentation will discuss the challenges faced and overcome with the remediation of a major trunk sewer straddled under the London Underground tunnel and under one of London busiest arterial routes. The existing structure was constructed when the underground was first constructed in 1863 and it required major structural enhancement.
Given the constraints a high innovative solution was adopted which involved strengthening the sewer from the inside without the need for any excavation or disruption to traffic or the underground network. The technical solution involved the installation of a modular Vierendeel truss in duplex stainless steel with an inner fibre reinforced plastic (FRP) liner to carry the sewage.