TITLE: Instrumented Tunnel Construction – A Unique DUSEL Opportunity
Auth1: Marte Gutierrez * magutier@vt.edu
Auth2: Herbert Einstein
Auth3: Matthew Mauldon
Auth4:
Auth5:
Auth6:

TEXT: (or see attached pdf file)

The planned Deep Underground Science and Engineering Laboratory (DUSEL) provides a unique and exciting opportunity to develop, test and validate new and innovative techniques for tunneling. DUSEL will be unique in that it will require the construction of large caverns located at large depths approaching 7000 ft. The construction of the access tunnels and caverns for experimental facilities will pose several challenges that need to be addressed by new technologies for rock mass characterization, tunnel design, and tunnel excavation and support. Lessons learned from building DUSEL can be used to improve tunneling technology. Rock failure in underground mines and tunnel construction continue to claim lives, and the tunneling industry is still beset by cost overruns and frequent failures. These problems can be reduced by better knowledge of rock mass behavior and improved tunneling technology. To gain improved knowledge on rock mass behavior it is proposed to use the caverns and portions of the access tunnel as “research tunnels” during construction. By converting parts of DUSEL into “research tunnels” different types of studies can be carried during the construction and use of the tunnels and caverns. These studies include: 1) comprehensive geological and geotechnical characterization for rock mass modeling, 2) instrumenting and monitoring of the rock mass, the tunnel support system, and the tunneling equipment during the construction, and 3) using and testing different methods of excavation and different types of support systems along different parts of the tunnel, and 4) comparing different tunnel analysis methods amongst each other and with the observed performance. Major technological developments expected from the research to be carried out in the “research tunnels” include development of novel and innovative technologies for: 1) advanced geologic and geomechnical modeling of rock masses, 2) visualizing and interacting with computational models of tunnel excavation 3) digital imaging and analysis for geologic characterization of rock masses, 4) remote measuring and monitoring of tunnel response during construction and 5) monitoring stress changes within the rock mass due to excavation using computer tomography. It will also be attempted, in collaboration with the tunneling industry, to apply and evaluate new excavation and support methods which speed up and lower the cost of tunnel construction.