If you have a pass-thru yard that has curved tracks are they super-elevated?
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Given the speeds in a yard, I doubt they'd super-elevate the curves. Even a hypothetical mainline running "through" a yard would likely be operating at reduced speed (25MPH or less) so there probably would be no need for super-elevation. Hopefully Tom (Number90) or Jack (Hot Water) will chime in.
SantaFeJim posted:If you have a pass-thru yard that has curved tracks are they super-elevated?
No, Jim.
With the minimal speed on yard tracks, even on a main going thru a curved yard, reduced speed in order. No need for super-elevation at all.
Melvin P posted:With the minimal speed on yard tracks, even on a main going thru a curved yard, reduced speed in order. No need for super-elevation at all.
Not necessarily. Tack for example, the former C&NW Proviso Yard (now UP), is curved, yet has a double track main line to the north side of the yard, and there is no speed restriction on the curved main line, which is super-elevated, for the METRA commuter service. Thus, the main line is NOT within "Yard Limits".
Thanks all for the FAST response. I did not realize that the 3RS forum get so much traffic.
When walking around around the Selkirk yard and bridges,(one of which no longer exists) back in '09 it did appear the outer most clarification tracks were indeed tilted in towards the center of the bowl. These tracks also included 2 or more retarders as they were also the longest.
Jim, superelevation is used on main track curves, to allow trains to operate at a faster speed, and to control wear on the inside edges of the rail, by managing lateral forces. The speed listed in the timetable is the balancing speed for that curve.
At low speeds, superelevation does more harm than good, as it increases lateral force by shifting most of the weight onto the low rail, wearing the wheel flanges and the low rail disproportionately. Even where there is, say, a 60 MPH super elevated curve paralleled by a 20 MPH siding, the siding will typically have no superelevation.
Yards, no. Superelevation would cause rail wear and plate-cut ties, and enhance opportunities for rolling the low rail when starting to pull a long cut of cars out of the track. Most yard ties are not the best on the railroad, and the least lateral force applied to them, the more sleep the Trainmaster gets.
