Site characterization alternatives for numerical models of a deep excavation

A cut-and-cover railway tunnel site on the outskirts of Barcelona benefited from an extensive site investigation campaign. During the construction of the tunnel, the displacement of the wall as well as the of soil beneath was recorded. A 2D numerical model of the excavation sequence was established. The large amount of site investigation data allowed a systematic comparative approach. Four different soil characterization strategies were mimicked, deliberately ignoring one or another subset of the characterization data. While results from CPTu and SPT were assumed equally available to all the hypothetical designers, the extra information for one of them was only laboratory test results, for another one it was pre-bored PMT data, for the third one it was SBPM and cross-hole tests data and, finally, the last one had DMT, SDMT and cross-hole tests data as complementary information. The simulation results are obtained using the Hardening soil model.