ABSTRACT
The behaviour of existing cast-iron (CI) tunnels subjected to ground movements induced by new tunnelling works is a much discussed topic. In many cases new tunnels and shafts, particularly in highly populated urban areas, will need to be constructed adjacent to existing tunnels. This inevitably results in ground deformations that are transmitted to these structures. This paper investigates the response and the radial tolerance of CI lining to these imposed movements. This paper highlights the common ‘damage assessment’ procedures in practice and emphasizes the need of paying equal attention to historical case studies when carrying out often complex analyses. A recent case study from the construction of Crossrail Line (Queen Elizabeth Line) in London has been presented to demonstrate this. In this example the CI lining is subjected to significant deformations caused by nearby tunnelling and excavation works.
