Planning, Deisgn, and Construction Considerations for a Drill and Blast Utility Tunnel

Abstract

The construction of a new utility tunnel associated with its hospital operations at the McGill University’s downtown Montreal campus was carried out by drill and blast. The tunnel passes within 6 meters directly beneath and adjacent to buildings that house sensitive facilities, equipment, research laboratories, medical treatment rooms and patients.

In order to maintain all hospital activities during tunnel construction, certain constraints related to peak particle velocities and blast overpressure, and audible blast noise measured at selected locations were imposed on the Contractor. The paper provides planning and design considerations that were used in the alignment selection, evaluation of applicable construction methods, the process used to set baseline parameters and the monitoring program, and the results of their implementation during construction.