e-mosty June 2017: Osman Gazi B. US Suspension. Hålogaland B. e-mosty June 2017: Suspension Bridges | Page 61

3.8 Cable Access System
The contract documents required both low-level and
high-level access to the main suspension cables;
however the means and methods were left to the
contractor. Specifications were developed to convey
the constraints for cable access, including minimizing
disruptions to traffic and sustained lane closures.
In response, the contractor implemented a temporary
main cable access platform (catwalk) that ran
continuously from one end of the cable to the other
(Figure 27). The access platform allowed multiple
tasks to occur on the cable simultaneously, such as
removing the existing wrapping, installing new
wrapping, sealing the cable bands and erecting the
dry air piping. It was interesting to note that the
method of access to the cable was different than the
traveling gantries that had been used on the UK
projects.
There are advantages and disadvantages to each,
which the market and project constraints will dictate.
However, since the Bay Bridge has been completed,
similar full-length platforms have been used on other
cable dehumidification projects in the US.
4. CONCLUSION
The dehumidification of the cables on the Bay Bridge,
as well as other structural and preservation work was
completed in approximately 30 months. The project
was the first-of-its-kind in North America and
garnered a lot of attention in the industry, including
five regional and national awards, and has since set
the stage for the adoption of cable dehumidification
as a preservation strategy on eight other bridges in
the US.
5. ACKNOWLEDGEMENT
The authors would like to firstly thank the Maryland
Transportation Authority for not only the opportunity
to work on this unique and challenging project, but
also the opportunity to present it. Thank-you to
Messrs. Abey Tamrat, Brian Wolfe, Will Pines and Dan
Williams.
The authors would also like to acknowledge the
following in the AECOM cable dehumidification
practice for either their contributions to the project or
the development of this paper – Charles Cocksedge,
Daniel Faust, Mark Bulmer, Barry Colford, Paul
Brumpton, David Wilkinson, James Kawchak, and
David Duke.
2/2017
Figure 27: Main cable access platform; Westbound Bridge
shown, Eastbound Similar
(Photo Credit: Christian Christodoulou, AECOM)
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