Experience from short-and long-term performance of deep excavations in soft sensitive clays

Abstract Design of excavations and permanent underground structures requires accurate predictions e.g. deformations earth pressures for both the short-and long-term. As excavation depths increase and/or proximity to adjacent infrastructure decreases, there is a need improve develop existing design methods validate numerical models. The first part this paper revisits measurement data from previous excavation, Göta Tunnel in Gothenburg, Sweden, order benchmark contemporary constitutive soil model, called Creep-SCLAY1S. This study looks into time series including final dewatering followed by development pore water pressures, over (until 2 years after excavation). model are general good agreement with up dewatering. However, installation effects due drilling believed have caused continued which difficult capture model. Part two presents details recently instrumented soft clay Central Gothenburg. comprises as well vertical horizontal at three locations under structure. Continued long-term measurements planned future provide valuable insights on stress state clay.