# Oversized cargo and HSR



## Joel N. Weber II (Mar 7, 2010)

Wikipedia's Wind farm article says:



> Transporting large wind turbine components (tower sections, nacelles, and blades) is much easier over water than on land, because ships and barges can handle large loads more easily than trucks/lorries or trains. On land, large goods vehicles must negotiate bends on roadways, which fixes the maximum length of a wind turbine blade that can move from point to point on the road network; no such limitation exists for transport on open water.


To get an idea of the size of a large blade used in an offshore wind farm, I looked at Wikipedia's Cape Wind article, which claims the blade diameter for that project will be 364 feet.

Consider a railroad car 400 feet long, on a track with a curve with a 20,000 foot radius. (I believe that in practice, 186 MPH track has a somewhat larger curve radius than that). Consider a right triangle whose points are the center of the circle, the center of the width of the railroad car at one end of the railroad car, and the center of the railroad car. The square root of (20,000 * 20,000 - 400 * 400) is about one foot less than the 20,000 feet, which suggests that, assuming our 400 foot railroad car has the same width throughout its length, it will be about one foot closer to the center of the circle at its center than at its ends.

This suggests that curves intended for 186 MPH and faster operation probably will not by themselves prevent the use of the track to transport 400' long wind turbine parts.

However, that still leaves open the question of whether the other dimensions of a wind turbine blade will fit within the clearance of a railroad.

Also, there's the question of whether any 45 MPH interchanges connecting one 186 MPH+ track to another 186 MPH+ track will present an obstacle. (Perhaps a crane can be used to move a wind turbine part from a railroad car on one track to a railroad car on another track. Or perhaps the interchanges could be built so that the insides of the curves have space for oversize freight.)

There's the question of whether catenary supports might get in the way. I think there are several possible options here: temporarily removing parts of the catenary system where wind turbine parts are being unloaded, or building some catenary supports with a very strong vertical support on one side of the track so that the vertical support on the other side of the track is unneeded. I believe the catenary in Massachusetts (which is probably about the newest catenary in the US and thus a reasonable thing to look at to get a sense of modern practice) tends to have poles every 200'; on that spacing, it might be possible to put the center of a 364' wind turbine blade directly between a pair of vertical catenary poles, and rotate the blade and then slide it off the railroad car.

When designing high speed track, it might be desirable for each high speed rail system to have both a connection to an airport that could be used for oversize freight, and a connection to a port that could be used to transfer oversized freight from ships.

I'm imagining that oversized freight shipments might happen during track maintenance windows, if track maintenance were generally scheduled for midnight to 6 AM, and if the track maintenance crews end up not needing to use every single maintenance window for track work. And I would not expect the oversized shipments to occur at high speeds.

Being able to build onshore wind farms with larger blades may turn out to be a more cost effective option than the alternatives, though it seems likely that not enough high speed track will be built near enough to good wind farm locations for a substantial fraction of the US's energy consumption to be powered by onshore wind turbines where the blades were delivered via high speed tracks.

I do wonder if the California High Speed Rail folks have looked at whether there might be any US Department of Energy grant money available to study these possibilities and to construct any infrastructure which might be useful for shipping large wind turbine parts but not directly useful to passenger rail.


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## George Harris (Mar 8, 2010)

The issue is not the total diameter of the blades, but the length of one blade which will be slightly less than half of the blade diameter. The blades do not meet in the middle. There is a hub section.

Thus, you are looking at a total length of load of about 180 feet. If mounted as appropriate for an oversize load, it will be supported at points such that about 70% of the length is between supports and 15% overhangs each end of the support. This proportion results in approximately equal outside and inside overhang on curves.

Therefore, for curves of larger than about 2300 feet (2 degrees 30 minutes) no consideration for excess overhang is needed. For cruves of smaller radii down to about about 1430 feet (4 degrees) there would be such things as stopping trains on adjacent track for meets, etc. Only when you get to 6 ot 8 degrees or more, would you have to start thinking about such things as clearances to signal masts, piers of overhead bridges, tunnels on curves and such like.

The one thing going for shipping these things on a high speed track would be their likely light weight, so the axle loads would be low. The show stopper would be the need to run these things at relatively slow speeds. Running these things at night would be impractical for two reasons. Generally hgih speed lines do their inspection and maintenance during night time shut downs from around midnight to 6:00am. The need for operation under observation would require lights if run at night. And then finally, if something goes wrong and the train does not clear up in time, you have seriously impacted your bread and butter.

In general, shipping these things on the regular railroad routes would be far more practical than trying to run them on a high speed line.


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## jis (Mar 8, 2010)

The other consideration on HSR would be keeping axle loads as low as possible, so as to keep track maintenance cost under control within reason while keeping tracks upto standard to provide a smooth ride at high speed. Already the case is that there are no high speed tracks in the US that we are able to maintain at the level of standard that the Europeans and Japanese manage with their HSR lines. One factor there is careful control of axle loads and train dynamics to minimize damage to the tracks under normal operation.


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## Joel N. Weber II (Mar 12, 2010)

Isn't there also a complete lack of concrete slab high speed rail in the US, even by Ohio's 79 MPH standard of high speed?

(The MBTA does have some concrete slab track in the subway system, I believe, but I don't think any of that gets up to 79 MPH.)


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## jis (Mar 12, 2010)

Joel N. Weber II said:


> Isn't there also a complete lack of concrete slab high speed rail in the US, even by Ohio's 79 MPH standard of high speed?
> (The MBTA does have some concrete slab track in the subway system, I believe, but I don't think any of that gets up to 79 MPH.)


LIRR has ballastless track on the Babylon branch. But not really high speed track.


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## George Harris (Mar 16, 2010)

Joel N. Weber II said:


> Isn't there also a complete lack of concrete slab high speed rail in the US, even by Ohio's 79 MPH standard of high speed?


A non-issue.

There are several high speed track slab systems that are known to those that will be doing the design of such track in the US.


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## jis (Mar 16, 2010)

George Harris said:


> Joel N. Weber II said:
> 
> 
> > Isn't there also a complete lack of concrete slab high speed rail in the US, even by Ohio's 79 MPH standard of high speed?
> ...


Exactly. The Chinese are afterall using German technology from a few friends that we already know well.


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