ABSTRACT
New underground stations up to 40 m deep for the Crossrail project in the London have been constructed. Excavations were supported by diaphragm walls or secant pile wall, using either the top-down or bottom-up construction sequence. To investigate the effects of these deep excavations on the existing adjacent buildings and tunnels, 3D FE models have been developed. The non-linear elastic plastic soil constitutive model—BRICK was used to model the behavior of London Clay and Lambeth Group. A back-analysis of the field inclinometer data from Tottenham Court Road Station—Western Ticket Hall was carried out using the 3D FEM. Revised BRICK parameters were derived from the back-analysis and applied in three other Crossrail excavations. The back analysis of four excavations has provided an intensive review on the BRICK model parameters for London Clay. The reliability of the BRICK model in London Clay to assess most probable ground movements has been demonstrated.
