BGS Walkways

[BigMattFromTexas]

Im not sure I would just put my life on what looks like some small metal bars attached to bigger metal platforms... Thats just me, would any of yall?
BigMatt

[Scott5114]

Kansas has catwalks that feature little handrails that fold down when they're not in use. They are invisible to the motorist most of the time. They are occasionally left up after use, though.

[Alps]

Matt, I don't think your photo has a catwalk on it, just lighting support.  If anything, workers would walk out over the truss and hang down, but probably they'd drive underneath in a cherry-picker with cones set up.  NJ has real catwalks, for comparison:

http://maps.google.com/maps?f=q&source=s_q&hl=en&geocode=&q=parsippany&sll=37.0625,-95.677068&sspn=30.461748,63.369141&ie=UTF8&hq=&hnear=Parsippany,+Morris,+New+Jersey&ll=40.866519,-74.43778&spn=0.007091,0.015471&z=16&layer=c&cbll=40.866521,-74.437891&panoid=SCevSZBkcjYMzSZhQ1WKYg&cbp=12,267.96,,0,-7.11

[Chris]

How about this installation on Autobahn A3 in Germany between Cologne and Frankfurt?

It's a cash cow, basically. It has a steep uphill ascent, with trucks doing as slow as 25 mph, which caused many accidents, so the two left lanes are now limited at 60 mph. It's controlled by a radar installation that generated € 1.8 million in speed tickets in 2006 alone.



old pic, couldn't find a newer one from the back of this installation:

[roadfro]

Nevada DOT has a couple types of methods for dealing with the BGS lighting.

For older sign installations, especially those that are smaller or those mounted along bridges, there is no walkway provided.  These are generally in the median or above the inner or outer lane where it would be fairly simple to close a lane of traffic while a cherry picker is stationed below the sign for lighting maintenance.

On older multi-sign light installations, the method is similar to the Kansas method Scott mentioned. A walkway is provided with a fold-down safety rail. Walkways are only provided on new sign bridges if a dynamic message sign is present.

The new standard for BGS lighting involves a system that NDOT calls a "luminaire retrieval system".  The light fixtures are attached to a movable mount within a track. A crank is located to one side of the assembly--generally at the right pole support of the sign bridge.  This assembly allows NDOT workers to move the light fixtures over above the shoulder to perform maintenance instead of walking out along a catwalk above traffic to access the luminaires.

The luminaire retrieval system was first implemented in sign replacements during Phase 1 of the Las Vegas US 95 widening circa 2001-2002; the system is now used all over the state.  I don't know of a good picture of one of these installations, but here is a Google Maps Street View example of one of those early US 95 installations--you can kinda see the handle of the crank assembly there on the right side.