What is a track profile, like this?
In the UK that is not a track profile (may be called that in USA)… that is a gradient profile… I can see that even in tiny pic (loads quick though!)
A Gradient profile shows all the gradients and the distance they run for (including level) from one end of a line to another… or between designated points on a line. Each Signalbox used to have a gradient profile for the running track it controlled. It’s purpose is to tell you how steep different parts of the line are… this has a bearing on the loads and speeds… and braking requirements … of trains… also, if you know where a train has failed you can see what line it will have to be re-started on and pushed (or pulled ) out over.
A track profile (in the UK) is the cross section of the WHOLE track from ground to rail head perpendicular to the rail from one worked extreme to the other. It may or may not include drains immediately to the side… it would include the outer ditches. It will show one, two, four track standard configurations. Special examples might show two tracks with an adjacent but seperate third track. They are almost only for running track NOT yard tracks.
Rail profile is the perpendicular cross section of the rail… flat bottomed (vignoles), bull head, bridge (which in this case is not rail that goes on bridges… although it could) or whatever. The sections vary by rail weight… but even for the same weight (per yard or per metre) there are many rail sections.
David Foster’s answer applies to the USA as well – grade profile and rail profile are two different things entirely.