Drip sealing of tunnels in hard rock: A new concept for the design and evaluation of permeation grouting
Journal article, 2010

This paper presents a new pre-excavation grouting concept to prevent dripping and reduce the inflow into a railway tunnel. For this purpose, the tunnel's roof was drip-sealed using colloidal silica and the walls and invert of the tunnel were grouted with cement. The grouting design process followed a structured approach with pre-investigations of core-drilled boreholes providing parameters for the layout. Water pressure tests and pressure volume time recordings were used for the evaluation. Results showed that the design was successful: the total transmissivity was reduced from 4.9 x 10(-08) m(2)/s to the measurement limit (1.6 x 10(-08) m(2)/s), and the dripping was reduced to eight spots from the roof. Improved rock characterisation showed that the grout hole separation was within the transmissivity correlation length and that grouting efficiency depends to a large extent on the dimensionality of the flow system of the rock mass. (c) 2009 Elsevier Ltd. All rights reserved.

Grouting design

Dripping

Grouting evaluation

Silica Sol

Hard rock

Cement

Author

Christian Butron

Chalmers, Civil and Environmental Engineering, GeoEngineering

Gunnar Gustafson

Chalmers, Civil and Environmental Engineering, GeoEngineering

Åsa Fransson

Chalmers, Civil and Environmental Engineering, GeoEngineering

Johan Funehag

Chalmers, Civil and Environmental Engineering, GeoEngineering

Tunnelling and Underground Space Technology

0886-7798 (ISSN)

Vol. 25 2 114-121

Subject Categories

Civil Engineering

DOI

10.1016/j.tust.2009.09.008

More information

Created

10/8/2017