Technology

Sound Transit floating bridge tech for light rail wins award

Posted on November 1, 2017

Sound Transit’s light rail system from downtown Seattle to Redmond via I-90, light rail vehicles will travel across the Homer M. Hadley Memorial Bridge over Lake Washington. Photo: Sound Transit
Sound Transit’s light rail system from downtown Seattle to Redmond via I-90, light rail vehicles will travel across the Homer M. Hadley Memorial Bridge over Lake Washington. Photo: Sound Transit

Sound Transit's technology to enable light rail trains to travel across Lake Washington on the I-90 floating bridge has received a 2017 Best of What's New award from Popular Science.

As part of the East Link project, a 14-mile extension of Sound Transit’s light rail system from downtown Seattle to Redmond via I-90, light rail vehicles will travel across the Homer M. Hadley Memorial Bridge over Lake Washington. It will be the first light rail line in the world to operate on a floating bridge.

WSP USA led and managed a multidisciplinary team, including the University of Washington and the Transportation Technology Center Inc., to conceive and develop an innovative concept from computer modeling and analysis through detailed design and prototype testing of a “track bridge” technology that will enable light rail vehicles to transition from the fixed to the floating sections of the I-90 bridge. Trains will travel on a 1.1-mile floating span linked via transition spans to concrete box girder approach spans on either end.

The structural system is subject to dynamic, multidimensional movement of the bridge deck at the existing expansion joints, due to changing lake elevations, vehicle traffic loading, wind, waves and, for extreme conditions, the breaking of anchor cables, all of which were addressed in the design. Development of the design required the collaboration of a team consisting of track and structural engineers, computer modelers, research specialists and special trackwork fabricators, working with construction experts, to take the project from concept through full-scale prototype testing.

The WSP team conceived, developed and demonstrated a novel concept, the Curved Element Supported Rail (CESuRa) system, which works through the interaction of curved and rotating track supports, which automatically adjust for multi-directional movements of the supporting bridge deck. This innovative approach addressed yaw, pitch and roll movements and will provide a smooth alignment and profile under all movement combinations.

The track bridge concept was tested by operating two Link light rail vehicles at up to 55 miles per hour across two prototype track bridges at the Transportation Technology Center in Pueblo, Colorado in 2013.

East Link is now under construction, with completion expected in 2023.

View comments or post a comment on this story. (0 Comments)

More News

MTA expands tap payment system to Penn Station

The agency reached one million taps within three months of its initial launch, with the number rapidly climbing toward the milestone of four million tap.

New York MTA launch subway signaling challenge

Program was announced the agency's Signaling Innovation Summit, which included a Demo Day.

Report offers framework for transportation integration into smart cities

Cities working together can accelerate the iterative process through knowledge sharing, development of best practices.

INIT opens west coast development center

The growing team will continue to invest in open API development, custom reporting, and third-party integrations to support INIT’s fare collection customers.

Singapore tops urban mobility readiness report

“Cities who embrace technology and have proactive regulation will become leaders in the mobility revolution.”

See More News

Post a Comment

Post Comment

Comments (0)

More From The World's Largest Fleet Publisher

Automotive Fleet

The Car and truck fleet and leasing management magazine

Business Fleet

managing 10-50 company vehicles

Fleet Financials

Executive vehicle management

Government Fleet

managing public sector vehicles & equipment

TruckingInfo.com

THE COMMERCIAL TRUCK INDUSTRY’S MOST IN-DEPTH INFORMATION SOURCE

Work Truck Magazine

The number 1 resource for vocational truck fleets

Schoolbus Fleet

Serving school transportation professionals in the U.S. and Canada

LCT Magazine

Global Resource For Limousine and Bus Transportation