Safety engineering in tunnelling with traditional technique through gassy rock masses and soils
Client: DIRPA 2 S.c.a.r.l.
Project: Road axis Marche – Umbria and district of internal penetration Maxilotto n. 2, Pedemontana delle Marche, tract “Fabriano – Muccia / Sfercia”
Date: 2016 in progress
The “Pedemontana delle Marche” project contemplates the excavation of several natural and artificial tunnels in potentially gassy rock masses and soils.
SERENGEO’s activity consists in technical – scientific assistance, during design and construction phases, on safety against detonation or deflagration of air – methane mixtures during the tunnels construction works.
 Pedemontana delle Marche track (light blue line) and tunnels (orange lines) |
 Serre tunnel’s face |
Project Goals
- Assessment of the likelihood that the excavation works can determine methane inflows towards the tunnels;
- Specific guidance for safe design and construction of tunnels in gassy rock masses.
Serre tunnel’s geological profile
Activities performed
- Bibliographic and documental analysis in order to evaluate the potential presence of methane in the rock masses interested by the construction works;
- Definition of an Integrative Methane Investigation Plan;
- Analysis of the methane investigation results and correlation with the geo-structural framework;
- Technical classification of tunnels in relation to methane risk, in application of the Marche Region’s Technical Note “Safety standards to apply during the realization of main infrastructural works: Underground works – Excavation in gassy soils” (Decree n.18/SPU, date: 06/09/2013);
- Definition of the technical measures and procedures to be used during tunnels construction to ensure the highest safety level against air / methane mixtures detonation and explosion;
- Technical support during construction phase, verification and update of the technical classification.
Methane emissions measured ante operam at boreholes head and during gas trap measurement