Predictions and instrumentation of an extensive monitoring scheme in the Netherlands, Second Heinenoord tunnel

In 1993, the Dutch government decided to finance two experimental TBM tunnelling projects. The first is the Second Heinenoord tunnel under the river Oude Maas, the other will be the Botlek Railway tunnel under the same river near Botlek to replace the existing Botlek bridge. Both are situated south of Rotterdam. To support tunnelling activities in the Netherlands, the Dutch government decided in 1994 to finance a first five year research and development program on tunnelling in extremely soft soil. The Centre for Underground Space Technology (COB), especially set up for this program, has welcomed more than one hundred companies, institutes, etc. as contributors until now. This paper contains an overview of predictions made and instrumentation placed for research on the behaviour of the tunnel boring machine (TBM), surrounding soil layers and tunnel lining. Typical problems as soft multi-layered granular soil and high groundwater level draws special attention to the validation of design models. used worldwide. The special relationship between the principal of the tunnel project, the contractor and researchers is outlined as well. As far as possible preliminary results of the first measurements will be presented.