Would it be too difficult for you to post that number? That site has many good hits. My favorite is the hit that only took off the roof AC units of the coach. I have never pulled a trailer that was 13'6". I doubt if any of them were more than 13'2" at most. All were 53' dry vans.
Bridges are marked at their lowest point. Most cases it is at a end or the shoulder of the road. The PA turnpike is a good example. And most bridges are also given a 2-4 inch span to allow for snow pack.
Chicago isn't the best at updating their signs for low bridges. And in some areas the "locals" get a kick, or (use it to their advantage....if you know what I mean) out of taking them down, or defacing them. I have experiences Chicago and surrounding areas paving the road time after time shortening the heighth and never changing the sign, or vise versa. So always be safe.... get out and look.
Sure do! heard of many of drivers having their trailers unloaded for them. And nothing your going to do about it
Another trick with a RR bridge that is close is to wait if there is a train on it. The train can cause the bridge to sag. Learned that from a buddy who is a bedbugger. He had to do that a couple times in Chicago.
I hate going back east because of this. Those bridges were built before there even were "big" trucks in many cases. Hell, even before there were "autos" in some cases. I was in Bridgeton, NJ (fitting name in my case) pulling a 13'6 reefer several months ago and came across a RR overpass marked at 13'2 or 13'4. Two lane road, so didn't want to block traffic. Plenty of warning after the sign, so I pulled off the side of the HWY (I think it was 77, maybe?) into some kind of antique or cloth shop. As I was calling my dispatcher to tell him that I was screwed, I saw a Papa John's truck pulling a 13'6 reefer go right under it, so on I went. Seriously.... with all the billions of dollars in the trucking industry and with all the revenue that the shipping and receiving of procut brings into states through taxes, you'd think that someone could produce a coordinated effort to properly mark overpasses and then apply them to a #### map.