Responding to an increasing demand of underground
infrastructures monitoring of hydro-geotechnical and structural
parameters during the construction of urban tunnels in soils
and rock (except hard rock) is a field of activity which has seen
impressive technological changes and progress in the past years.
In the majority of the cases the construction of such urban
underground infrastructures is to be carried out in difficult ground
conditions and / or with limited knowledge about the ground
parameters. In consequence the so-called ‘observation method’
according to Eurocode 7 is applied:
Eurocode 7, Section 2, chap. 2.7 Observation method (1) If
the prediction of the geotechnical behavior is difficult, it may be
appropriate to apply the so-called observation method which
consists in the control and, case given, in the modification of the
design during the construction.