The main purpose of pre-excavation tunnel grouting is to reduce water leakage and prevent the lowering of the ground water table. A successful sealing of rock requires thorough grouting design and accurate material selection. A detailed grouting technique - specification is also required; this should be based in parameters evaluated after a combination of pre-investigation results and scientific research (arithmetical calculations).

In Finland, there are currently no national guidelines (design principles-standards) related to rock tunnel grouting neither Eurocodes explicitly describing the process of grouting designing.

A traditional approach to define the materials and design principles of pre-grouting included the following:

  • Consideration of the water tightness class & geological conditions

  • Empirical knowledge and experiences from similar projects

Still, is this approach sufficient towards a successful result-driven implementation, also making economical sense?

The main scope of this paper is to present the grouting design methods used in urban projects in Finland so far; on this basis, the principles of a strategy that could increase the grouting efficiency, along with the designer's working processes in the future will be also presented.

This content is only available via PDF.
You can access this article if you purchase or spend a download.