Beacon Hill Station and Tunnels win excellence award
August 16, 2010
Hatch Mott MacDonald’s Central Link Light Rail: Section 710 Beacon Hill Station and Tunnels project for Seattle Sound Transit recently received a Grand Award at the 2010 American Council of Engineering Companies (ACEC) Engineering Excellence Awards Gala.
The Beacon Hill Station and Tunnels project is a component of the new 16-mile Link Light Rail line that provides transportation between downtown Seattle and SeaTac International Airport.
The station location required an innovative approach to deep, complex tunneling in very poor soils and at a depth and a diameter close to twice that previously undertaken in North America. Finding a means to excavate the station tunnels safely was the central challenge of the project, and led to an innovative, segmental excavation method (SEM) that had never before been attempted at this scale or depth in North America.
The tunnels were completed using an innovative dual sidewall drift technique for the 14 m diameter concourse tunnels and a single sidewall drift method for the 11 m diameter platform tunnels. The 50 m deep twin tunnels are the deepest soft ground tunnels in North America. Construction of the time-critical, 18 m diameter access shaft was achieved by using an adaptation of the slurry-wall construction technique.
The Beacon Hill Station and Tunnels Project used state-of-the-art techniques that represent distinct and important advancements to the tunnel engineer’s art and skills.
The 2010 Engineering Excellence Awards Gala recognized 163 National Finalists and 24 top award winners, including Honor and Grand Award winners, and one Grand Conceptor Award for the top overall engineering triumph.
A panel of 28 judges representing a variety of disciplines across the nation selected award recipients based on criteria such as uniqueness and originality, technical complexity, social and economic value and public awareness.
Hatch Mott MacDonald also received a second Grand Award for the Sea-to-Sky Highway Improvement Project in British Columbia.