Authors: K H Holmøy B Nilsen
Publish Date: 2013/02/16
Volume: 47, Issue: 3, Pages: 853-868
Abstract
One of the most challenging aspects of tunnelling is prognostication of water inflows More reliable prediction of groundwater inflow may give considerable economical saving for future tunnel projects and may also prevent damage of environment and installations on the surface This paper is discussing the significance of eight hypotheses regarding geological parameters for predicting water inflow in tunnels The respective hypotheses have been tested as part of a recent research project in Norway Six Norwegian tunnels with different geological conditions were selected for the research the Romeriksporten Frøya Tbaneringen Lunner Skaugum and Storsand tunnels Based on detailed study of these tunnels the hypotheses are tested by comparing water inflow with geological parameters and factors such as Q value faulting rock stress orientation rock cover thickness of permeable soil or depth of lake/sea above the tunnel rock type and width of weakness zones It is found that four out of the eight tested hypotheses are supported two have low to medium support and two are not supported One unexpected result is that for the tunnels covered by this study the water inflow was found to increase with rock coverThis paper is based on PhDresearch carried out at NTNU Department of Geology and Mineral Resources Engineering at NTNU by the by the first author of this paper with the second author as supervisor The PhDproject was financed mainly by the Norwegian Public Roads Administration In addition the research programme “Tunnels for the citizens” and the Geological Survey of Norway have supported field work connected to this project The financial and scientific support from these parties is greatly acknowledged
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