PRECODE

In 2021, a new tunnel of about 100 m length will be excavated as an important infrastructure element for a project on earthquake research (FEAR) funded by the European Research Council (ERC) and the Werner Siemens Foundation. The basic idea of the research project PRECODE - PROGRESSIVE EXCAVATION DAMAGE ZONE EVOLUTION DURING AND POST MINE-BY TUNNELLING is to use a section of this new adit for a mine-by experiment with state-of-the-art monitoring tools aimed at a detailed understanding of:

1. damage initiation during tunnelling,
2. the progressive, time-dependent evolution of the excavation damage zone over many years and its couplings to hydraulic properties and long-term environmental variations, and
3. the effects of tunnelling on the reactivation and permeability of fault zones in the immediate vicinity of the tunnel.

The main objectives of PRECODE are:

• Improve our understanding of short-term rock mass behaviour during tunnelling with state-of-the-art monitoring systems that were not available in previous experiments in crystalline rock (e.g. fibre-optic strain sensors, highly sensitive microseismic sensors, LiDAR scanning, etc.).
• Improve our understanding of the influence of natural variations in environmental parameters (moisture, seismicity, etc.) on progressive, time-dependent microcrack development within the excavation damage zone.
• Determination of changes in excavation damage zone permeability over time (up to 2 years).
• Analysis of the impact of tunnel construction on potential reactivation of fault zones and the associated changes in their hydraulic properties
• Creation of a hydro-seismo-mechanically coupled reference data set for numerical simulations, which will be made available to modelling groups.

Project Leader Institution

Chair of Engineering Geology, RWTH Aachen University

Project Contact

Florian Amann

Funding

BGE (Bundesgesellschaft für Endlagerung, Deutschland)

Partners

ETH Zurich; BGE Technology GmbH; Civil Engineering department at the Lassonde School of Engineering, York University; Department of Civil and Resource Engineering, Dalhousie University