Deteriorating RR Overpasses

[Richard A]

Over the past 20 years I have traveled quite a bit throughout the Northeastern US and have marveled at the poor condition of some of the railroad overpasses in our cities. I know, it's all part of the infrastructure problem we have with all of our aging cities. Here is a link to an article that is both humourous and freightening.

I have personally witnessed falling stones (small) from a deteriorating CSX overpass in upstate New York. Within a month of the incident, CSX and the city had repaired the bad section.

http://wbal.com/stories/templates/news.asp?articleid=28181

[Anonymous]

It's not just railroads either... A huge portion of the transportation infrastructure was built after the war. So it's all aging at the same time. I watched a show... I forget the name, but it was all about America's transportation system, and they specifically talked about the problems with aging bridges... Both RR and vehicle. Some experts called it an epidemic, and said that a huge number of bridges are in great need of major refurbishing, or even replacement. But as usual, there's no money. They showed bridges on the East Coast that looked like they were about ready to fall apart. That bridge collapse that happen the other day with the covered hoppers is probably just one example of things to come.

Dave
-DPD Productions - Home of the TrainTenna RR Monitoring Antenna-
http://eje.railfan.net/dpdp/

[Anonymous]

That bridge collapse (I believe you are referring to one in Michigan) was the result of a derailed car striking the end of a through truss. A brand new bridge would have suffered an identical fate. While deteriorating bridges are a concern, that collapse is unrelated. Moreover, when people talk about deteriorating bridges, they are almost 100% concerned with highway bridges, which in the 1950s and 1960s were originally designed with 25-35 year economic lifespans. If you think when the Interstate Highway system was largely constructed, in the 1960s, a large number of highway bridges are coming due. Worse, because most of these bridges were green-field projects, their original erection didn't have to allow for on-going traffic flows. Now, however, these bridges carry immense traffic loads which can't simply be dumped onto city streets while a replacement project is undertaken. In some cases as much as 75% of the replacement cost of a major highway bridge is due to the necessity to preserve traffic flow. Bridge erection that if green-field would be 3-9 months in duration now sometimes require 2-4 years in order to keep traffic moving.

The deterioration of railroad viaducts and elevated rights of way in cities is more of an aesthetic concern and life-safety to pedestrians concern than a structural concern. I'm not diminishing unsightly appearance and the danger of spalling concrete, but they do not necessarily indicate that these bridges are in imminent danger of collapse. If you read the AREMA papers like I do, you'd be up on what's going on with the inspection and engineering analysis of legacy bridges. The railroad industry is not about to run substantial risk, because they have their own money and lives at risk, unlike the highway departments, which answer to a public that can barely rouse itself to click the channel changer until disaster strikes, and always believes it's someone else's money and lives at risk. It's a credit to the highway engineers that bridges built within the last 10 years are vastly more substantial than they ones they replaced, and have much longer economic lifespans. The problem we face is that in the haste to build the Interstate Highway system, standards were intentionally set low, and cheap was the order of the day. Ironic that so many in the public believe "quality was always better in the past," but in the case of highways, that ain't so.

That bridge collapse in Michigan is not a sign of things to come in railroads, in my opinion.

By the way, railroad bridges built today usually have 100-year economic lifespans.

OS

[JoeKoh]

Csx has repaired the viaducts here in Defiance.however one problem remains.Semi-trucks keep hitting the clinton and jefferson st viaducts.I dont think the truckers insurance companies want the bill for a late shipment for ups.
stay safe
Joe

[RudyRockvilleMD]

The CSX 's Relay Viaduct in Relay, MD was built in the 1800's, and it is still in use today, well over 100 years old. I agree with OS today's highway bridges are more substantial, and part of the reason might be better design and analysis methods.

[Anonymous]

I am old enough to remember by first trip the length of the Pennsylvania Turnpike with a 18 wheeler. All the bridges and overpasses back in the late 80's were interesting because the concrete having been poured a long time ago started to "Flake off" at stress points on the arches.

I believe all of the overpasses are now replaced with more modern bridges and work is still ongoing in certain areas of the highway.

I agree with the Relay Maryland Bridge. I also point towards Europe where some really massive stone bridges are still in place and used daily.

What does bother me is a major rail bridge across a valley near Pittsburgh has been left to rust in front of the world. What a load of scrap value and probably much better off being brought down and the metal sold instead of left to rust until it fails someday.

One of the most unique bridges I have ever crossed was a industrial Quarry in PA. Apparently they have quarried stone since colonial times and the only exit out of the docks for my covered wagon was across a section 1000 feet high and about 110 inches wide and perhaps several hundred yards long. You were told to hang out the window and keep the driver's steer tire on the 1 foot wide yellow line and ignore everything else once you were cleared to cross. I was handed a peice of paper asking what to do with my body and next of kin should I not make it.

That bridge took me a lifetime to cross.

I have witnessed recent bridge replacements that really improved the safety. Recent history channel and learning channel shows about bridges and engineering as well as inspections reinforce my belief that we care about our bridges.

[Anonymous]

HighIron, I always learn something from your experiences in trucking. Keep it coming.

The bridge you refer to, and others of that size, don't rust very fast. The rust tends to protect the steel beneath it from rust. Cor-ten and similar steels, which are popular on modern bridges, are "self-rusting" steels designed to form a superficial coating of rust that protects the steel beneath better than paint, in many environments. Demolishing bridges of that nature is usually much more costly than the scrap value of the steel that's recovered. It's highly dangerous work if the bridge is to be scrapped and it spans a deep waterway -- these things were never meant to be dismantled. The cheapest solution is to use explosives and drop it into the water and leave it there, but if the waterway isn't deep enough, then it becomes a hazard to navigation, and that solution is out. I love the looks of the "classic" steel trusses of the 1880-1950 era, especially the Pratt trusses, K-trusses, cantilever spans, and steel trestles of the 1920-1930 period, when bridges were built to handle very heavy steam locomotives, and if I had my way, every one of them would be preserved as an engineering monument for all time.

OS

[jchnhtfd]

One of the most important things to remember about bridges to take highways over or under railroads is... if it's a bridge for a highway over the railroad, it is almost always the property -- and the responsibility -- of whoever controls the highway: the State or Provincial DOT or some local government entity. As O.S. notes, most of these were built with a design life of 25 years. Most of them were also built a good bit more than 25 years ago. Most of the highway departments have insufficient resources to maintain them, for reasons which are much too complicated to go into here. And, not surprisingly, a number of them are in pretty tough shape. Not only that, but an astonishing number of them are carrying loads which are heavier -- sometimes a good deal heavier -- than the designer anticipated. This is a problem with the whole highway network in the US and, from the standpoint of an engineer who will hopefully retire fairly soon, it is going to be a jolly mess to fix which I hope to be well out of!

On the other hand, most railway structures are built for a design life of 50 to 100 years, and in general the railroads try to keep them up to snuff. There have been some exceptions, of course, but the track record (sorry abou the pun there!) is pretty impressive.

And I do second O.S.'s motion that some of them at least should be preserved as engineering monuments!

[tree68]

Starrucca Viaduct - 150 years young and still in use....

[fievel]

Thanks, o.s. for your interesting and informative comments!