Eurocode design of underground metro structures

Eurocodes were used for the design of a new metro, for which the contractor's design was undertaken largely between 1996 and 1999, when the Eurocodes were in their infancy. This paper discusses the experience, the difficulties encountered and the benefits gained by the project, with particular reference to the geotechnical design of the underground stations. Eurocodes 1, 2 and 7 were used for the design of the retaining walls for the deep stations. Two design parameters created challenges for the structural design of the reinforced concrete embedded retaining walls: a restriction on the maximum allowable crack width, and a large cover to the reinforcement, required by the construction method. Benefits were gained by using the observational method.