I was wondering what is involved in upgrading track/right of way for increasing operating speeds. For example, what has to be changed to increase top speed from 30mph to 50 mph or 80 mph? I assume there are minimums related to rail size, crossing protection, ballast depth, tie type or age, etc. Just looking for any general requirements for different speeds.

Thanks.

Check out http://www.fra.dot.gov/us/search and enter: "right of way" into the site serach function. The Federal Railroad Administration regulates this issue of rights of way. You can explore a lot of the factors regarding safety issues like grade crossings, population densities, etc.

Even more specifically, go to the FRA Rules --
CFR49, Volume 4, Chapter 2, part 213/Track Safety Standards:

http://www.access.gpo.gov/nara/cfr/wais ... 13_03.html

To save you a pile of reading . . .

Generally speed is controlled by two factors according to the FRA. The first is the class of track. The standards for the track increase the smoothness (both vertically and horizontally), rigidity and the ability to maintain gauge under load as the class increases and the inspection frequency increases as well. The table below shows the speeds allowed by class of track. My take on the rule is that Class 5 and below is pretty much "standard" track design. Class 6 and above requires a complete engineering analysis including dynamic testing of the equipment to be operated at those speeds.


…………………………Freight……Passenger
Excepted Track.....10.......Not allowed
Class 1 track........10.......15 m.p.h.
Class 2 track........25.......30 m.p.h.
Class 3 track........40.......60 m.p.h.
Class 4 track........60.......80 m.p.h.
Class 5 track........80.......90 m.p.h.
Class 6 track.................110 m.p.h.
Class 7 track.................125 m.p.h.
Class 8 track.................160 m.p.h.
Class 9 track.................200 m.p.h.


Interchange freight is pretty much limited max speed of 80 mph. The FRA allows passenger speed only if the freight trucks have an acceptable dynamic responses at speed or in another words, they have to have passenger trucks under the freight cars.

The other limitation is curvature. The standard FRA formula allows no more centrifugal force to the outside of the curve than the equivalent of having one rail three inches lower than the other. The formula does not have any variables for center of gravity, one shoe fits all. But there is provision in this part of the rule to ask for a wavier. The rule does allow up to six inches of "super elevation" on the outside rail which greatly increases the allowed speed. A wavier also may request more super elevation for the higher classes of track. Here is a table with degrees of curvature in 100 feet, max speed with no super elevation, and max speed with six inches of super elevation (all speeds rounded off):

Curvature . . . . 0 inches . . . .6 inches . . super elevation
3 degrees . . . .57 mph . . . . .99 mph
5 degrees . . . .29 mph . . . . .51 mph
7 degrees . . . .24 mph . . . . .43 mph
10 degrees . . .21 mph . . . . .36 mph

Hope this was what you were looking for.

Ed

Ed's discription was wonderful, but I would like to add the railroad self designates the class of its track up to class 5. The FRA or state authority can then inspect the track and may reduce its clasification, but the railroad is the orginal designator

For Class 6 and above all rules change. For the higher speeds, the railroad applies for the given class, and the regulartry authorties will review everything involved and negotiate a class based on track, equipment, signals (Cab signals and automatic stop is ussually required), and grade crossings (frequently a no no).

Randy Hees

When reading the FRA rules keep in mind that these are the bare minimum standards for the class track you are thinking of. Any deviation from these standards, no matter how small, will cause the track to become the next lower class. When you upgrade a track you will want to improve it enough to maintain your standard for a period of time. Some people will upgrade to at least the minimum standards for the next highest class of track to accomplish this. In many cases you will have to do better than that.

The FRA does not specify rail size as standard for operating speed. The freight railroad I work for runs trains 25 mph on 75 pound rail with no problems. The smaller the rail the more effective ties you will need to maintain higher train speeds safely.

John Bohon