Thursday, December 1, 2016
Main Cable Dehumidification – A Steady Shift in Preservation Strategy for Suspension Bridge Cables - 1.0 PDH

Valley Forge Casino Resort (formerly Radisson)
1160 First Avenue, King of Prussia, PA 19406

Meeting Area Location:  Parkview Ballroom

members $45; non-members $50; government $25; students $15

PLEASE RSVP BY 5:00 pm on November 25, 2016


Suspension bridges serve as iconic structures across the world and provide a vital link to the communities in which they serve. Today, there are approximately 147 major suspensions bridges around the globe with span lengths greater than 1,000 feet – with the U.S. home to nearly one-third.

The discovery of corrosion and cracked and broken wires within the main cables of many older suspension bridges and the consequent loss of strength has posed a serious problem for long-span bridge owners. Conventional corrosion protection systems, such as painting, oiling and wrapping, have been largely ineffective in preventing deterioration and loss of strength in main cables.

The largest contributing factor to the deterioration of the cables is – moisture. The ingress of moisture within the cables not only provides the catalyst for corrosion, but also provides the chemistry for the production of hydrogen as part of the cathodic reaction, which in its atomic form can diffuse into the high strength steel wires and can result in hydrogen induced stress corrosion cracking and brittle failures.

To combat the issue of moisture and its deleterious effects on the cable, main cable dehumidification was developed nearly 20 years ago in Japan to address deterioration found in bridge cables that were less than 10 years old. The premise of main cable dehumidification is to remove the moisture to a level where corrosion practically ceases and the driver for hydrogen embrittlement is reduced.

Since its inception, approximately 30 suspension bridges around the world have been dehumidified including the William Preston Lane, Jr. Memorial (Bay) Bridge in Maryland – the first of-its-kind project in North America. Since this time, additional main cable dehumidification projects are in planning, design or construction to include the Delaware Memorial Bridge (DE/NJ), S. 10th Street (Pittsburgh, PA), Anthony Wayne Bridge (Toledo, Ohio), Ben Franklin Bridge (Philadelphia, PA) and George Washington Bridge (New York, NY).

This presentation will describe the history of main cable dehumidification and provide details of the increasing application of the technology in the U.S. The presentation will also report on the success of dehumidification in arresting the further deterioration of suspension bridge cables where dehumidification systems have been installed.


Barry R. Colford, BSc., CEng, FICE - Barry Colford is Vice President and Preservation Practice Leader for Complex Bridges at AECOM. Barry leads AECOM’s long-span bridge preservation practices based in Philadelphia, PA. He is currently working on projects on the Delaware Memorial, Anthony Wayne, George Washington, S. 10th Street, Ben Franklin and Walt Whitman Bridges. Up until mid-2015, Barry was Chief Engineer and Bridgemaster of the Forth Road Bridge in Scotland, UK – a 3,300 ft. main span suspension bridge – and was responsible for the $100M capital works program.

Shane R. Beabes, PE - Shane Beabes is Associate Vice President and a Technical Lead in Preservation for Complex Bridges at AECOM. Shane was AECOM’s project manager for the cable and anchorage dehumidification work on the William Preston Lane, Jr. Memorial (Bay) Bridge – the first of-its-kind project in North America. He is currently serving as the Resident Engineer Construction and AECOM’s design manager for the dehumidification of the main cables on the Delaware Memorial Bridge – the second bridge to receive full-length main cable dehumidification in the U.S.

Meeting schedule:
5:30 pm - 6:30 pm  Social and Registration
6:30 pm - 7:15 pm  Dinner (chicken/fish/vegetarian) - please note preference in response
7:15 pm - 8:30 pm  Program

To register (REQUIRED):
Register Here (link), or you may email James Greco <> or call
(215) 606-0409 by the Friday before the meeting (11/25/2016).  

Mail checks payable to SEI-Phila Chapter (or bring to the meeting) to:
SEI Treasurer Mr. Dwayne Dottin
509 Beatty Rd.
Media, PA 19063


**Payment must be made for the cost of dinner if you make a reservation but are not able to attend, since we must pay this cost to the caterer.**