Structural Interactions in London Underground Upgrade Projects: The Tottenham Court Road Station Overbridges

摘要

The London Underground transportation system (the Tube) celebrated its 150th anniversary in 2013. It is not only the oldest of its kind worldwide but also one of the busiest, serving more than 1,2 billion passengers annually. Considering the huge socioeconomic value of the city's building stock and subsurface infrastructure, as well as the conditions of confined space, the design and execution of urban tunnelling projects pose significant engineering challenges. Accomplishment of such projects relies on a combination of design, construction, and structural monitoring exercises. This report aims to showcase aspects of project execution in this environment, focusing on the preservation of structural and functional integrity in the interaction of new and existing structures, based on experiences from a recently delivered project, namely tunnelling works for the Tottenham Court Road Station Upgrade in central London. The station upgrade will be fully complete by 2016. Two of the new entrances, the new ticket hall and the new Northern line access, will open in 2015 and be ready to connect to the Crossrail platforms when they open in 2018, via a shared ticket hall and a five-storey underground interchange.