Since 1995 we have already carried out more than 1000 borehole deformability tests in the course of preliminary exploration and during construction work. In addition, primary stress measurements with the triaxial cell CSIRO and borehole scans. Numerous boreholes were equipped with pneumatic or electric pore water pressure transducers, others were upgraded to Trivec and combined sliding deformer/inclinometer measuring points.

Stuttgart 21