3D modelling of a deep excavation in a sloping site for the assessment of induced ground movements

A high-rise tower, which will be the highest building in Monaco, is currently under construction in a densely built area. The 150 m high tower consists of a 10 level deep basement, excavated on a 1/3 slope. The exceptional depth of this excavation (72 m on the uphill side), the steep sloping terrain, the site’s exiguity, the built environment and the presence of a poor marlstone layer at depth all contributed to adopting a 3D approach at the early design stage of the retaining solution to ensure:

– Safety against loss of overall stability (GEO limit state),

– Limitation of the induced displacements and settlements at the foundations of adjacent buildings (SLS limit state).