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This paper describes the application of a generalized effective stress soil model, MIT-S1, within a commercial finite-element program, for simulating the performance of the support system for the 20-m-deep excavation of the M1 pit adjacent to the primary station 'Hauptbahnhof' in Berlin. The M1 pit was excavated underwater and supported by a perimeter diaphragm wall with a single row of prestressed anchors. Parameters for the soil model were derived from an extensive program of laboratory tests on the local Berlin sands. This calibration process highlights the practical difficulties both in the measurements of critical state soil properties and in the selection of model parameters. The predictions for excavation performance are strongly affected by the vertical profiles of two key state parameters: the initial earth pressure ratio, K0; and the in situ void ratio, e0. These parameters were estimated from field dynamic penetration test data and geological history. The results showed good agreement between computed and measured wall deflections and tieback forces for three instrumented sections. Much larger wall deflections were measured at a fourth section and may be attributable to the spatial variability in sand properties that was not considered in the current analyses. The results of this study highlight the importance of basic state parameter information for the successful application of advanced soil models. [ABSTRACT FROM AUTHOR]