Subsurface Investigations, Design, and Construction Considerations for the Montreal Transportation Agency Cote-Vertu Underground Storage and Maintenance Garage

摘要

The Montreal Transportation Agency (Societe de Transport de Montreal-STM) is currently constructing the Cote-Vertu underground storage and maintenance garage that will facilitate daily operations and offer parking spaces for the new Azur trains. The project comprises three parallel tunnels of 1200 ft length each, 25 ft width with a pillar with of 16.5 ft; a 2,000 ft long connecting tunnel to the existing tunnel which will have caverns that have spans as large as 62 ft with very shallow rock cover. The contract requires the use of a roadheader to excavate the garage to ensure the stability of the pillars. The project crosses near known major faults. The paper addresses the geotechnical investigation programs, the design considerations and the selection of construction methods as well as provide updates on ongoing construction activities that started in May 2017.