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Having posted here much in the past I know that there are quite a few of you here who are quite familiar with rail operations, so I figured this would be a good place to direct my question.
I am currently doing a research paper for my Economics research class in which I am comparing the construction and operating costs of different light rail systems and trying to break things down to see why they may vary greatly from city to city. I had noticed that Sacramento had one of the cheapest per mile construction costs for its system, no doubt due in part to the single tracking that existed over much of the system early on. I also read that in the past they used wooden ties before switching over to the use of concrete ties. My question is this - Do any of you know of a good yet straightforward study done on this topic? I need one that has a decent amount of data such as how much it would cost to do a mile with one or the other type of ties, how long each might last, associated maintenance and so on. I'm trying to answer the question as to whether wooden ties saved them early on only with costs, if at all, or if there are long term savings as well, or if the needed maintenance and replacement would soon make the initial cost savings irrelevant.
I know this is a bit off topic since it has to do with light rail, but I know there were some here who commented on the use of concrete rail ties in the NEC, so I'm hopeful that some of you may have more good information on this. Thank you in advance for your responses.
JONATHON Member # 2899
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Wood- Instect concrete, it chips slowly away
Colt-45 Member # 3742
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Hello Empire Builder long time no see how are you? this is a good question for George Harris i hope he see's your post if not e-mail him i was looking for one of his answers on this but seem to have lost it.he will give you a very good complete answer on ties and rail
Instect? what is that?
Chucky Member # 2263
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Run, don't walk, to your local video store and rent the classic "The Graduate" starring Dustin Hoffman. Pay very close attention to the following dialogue:
Mr. McGuire: I just want to say one word to you - just one word. Ben: Yes sir. Mr. McGuire: Are you listening? Ben: Yes I am. Mr. McGuire: 'Plastics.' Ben: Exactly how do you mean? Mr. McGuire: There's a great future in plastics. Think about it. Will you think about it? Ben: Yes I will. Mr. McGuire: Shh! Enough said. That's a deal.
quote:Originally posted by EmpireBuilder: I am currently doing a research paper for my Economics research class in which I am comparing the construction and operating costs of different light rail systems and trying to break things down to see why they may vary greatly from city to city. I had noticed that Sacramento had one of the cheapest per mile construction costs for its system, no doubt due in part to the single tracking that existed over much of the system early on. I also read that in the past they used wooden ties before switching over to the use of concrete ties. My question is this - Do any of you know of a good yet straightforward study done on this topic? I need one that has a decent amount of data such as how much it would cost to do a mile with one or the other type of ties, how long each might last, associated maintenance and so on. I'm trying to answer the question as to whether wooden ties saved them early on only with costs, if at all, or if there are long term savings as well, or if the needed maintenance and replacement would soon make the initial cost savings irrelevant.
The answer is, "and uh yes, maybe, no, we'll have to think about it."
Generally the selection of one or the other type of tie will have absolutely no effect on the viability of the system and will have a vanishingly small effect on the initial cost of building it.
I am not as up to date on the relative costs of the various light rail systems in the US as I once was, but a lot of what bounces around in the public and trade press on costs is insufficient in completeness to enable any intelligent decisions to be made. A lot also comes under the heading of "Figures don't lie, but liars figure."
As to chucky's thing on the plastic tie, call me in 10 years and tell me how it is doing. I still feel like these things are a solution in search of a problem. The basic creosoted wood tie is a very reliable known entity, but that is not by a log way the only reason it has lasted so long. It has lasted as long as it has because of simple economics. The negative environmental effects of the creosote in the tie are highly exaggerated IMHO. The normal vacuum process results in very little leaching out of the material. There have been crys of wolf concerning the shortage of usable timber for wood crossties since at least the 1920's. Hasn't happened yet. In much of the southeast, bardwoods used for ties are still growing at rate faster than they are being harvested.
It is obvious that Union Pacific is installing a lot of concrete ties. It is equally obvious that Norfolk Southern is not. Both BNSF and CSX install both, but so far as I know, still are heavily into wood. The installed costs of the two different forms of ties are very close. So far as I know, the initial cost of the concrete tie in place is still higher than wood. Considering that most of the good hardwood used in ties grows in the southeast it could be that shipping is a factor in UP's higher usage of concrete and NS's higher usage of wood. When you do a present worth analysis between two material, one of which is supposed to have a 50 year life, the other of which is known to have a 35 year plus life, the increased life and future replacement virtually falls out of the picture.
In general railroads have gone to concrete for high traffic volume tracks particularly in areas with lots of curves on the basis that in thees areas wood ties wear out before they rot out. No one has been able to economically justify concrete for low volume low speed tracks.
There is a discussion of an econcomic analysis in the AREMA Manual, but it is quite sensitive to both traffic and component costs, so it does not give you a clear generally usable answer.
One of the factors in the higher use of concrete in transit systems is that with the nature of their funding, it is better to try reduce future maintenance costs at the expense of an otherwise uneconomically justifiable increase in first costs.
There are two main factors behind the much higher usage of concrete ties in Europe. One is the higher cost of wood and the other is their normal maintenance practice of segment by segment complete replacement. It has proven impractical to place concrete ties into tracks one at a time as the wood ties need replacing as is normal US practice for tie renewals.
email me if you want more. ghharris "at" yahoo.com. You are trying to write a paper on a subject about which books have been written and for which at this time there is no clear answer.
George
EmpireBuilder Member # 2036
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Mr. Harris,
I thank you for your offers or further help. I attempted to e-mail you, however, and for some reason the message did not go through. I will try again in case I have made a mistake with your address.
George Harris Member # 2077
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Oops. sorry. that should have been ghharris44 Today is the first time I have been able to access trainweb since Saturday.
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