In the past decade, in the Netherlands four bored tunnels with monitoring and research were constructed. Two of them, The Second Heinenoord tunnel and the Botlek Rail tunnel where pilot projects for Bore tunnelling. The research was commissioned by the Netherlands Centre for Underground Construction, COB. All of these have been constructed outside urban areas where settlements are not the main concern. However as we are intending to build a major Metro-line in the City of Amsterdam, an area where piled foundations are common, there is a major concern for settlements and interaction with piled foundations. In this discussion the focus will be on surface settlements, i.e. the predictability of these. Although there is a general agreement on the reliability of the empirical method by Peck, this method is restricted to simple situations, e.g. plane strain and limited to one or more parallel tunnels, no buildings. In order to enhance the design of tunnel structures and to improve the analysis for more complex situations, 2D Finite Element analysis for the construction phase, or 3D FE analysis for skew crossing tunnels would be desired. In this paper some results of monitoring at the Second Heinenoord tunnel, SHT and the Botlek Rail Tunnel, BRT will be given. The first was excavated with a Slurry type TBM, the second with an Earth Pressure Balance Shield, an EPB. The monitoring results are compared. Furthermore, some results of numerical analysis and some conclusions on its shortcomings and possibilities will be given.
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