Don't take it personal. Us FSU grads are not ganging up on you, although it may seem like it.
I have been in the public and private planning sector for over 30 years, and have served as the executive manager of a metropolitan planning organization as part of my professional pilgramage.
Your concept is very interesting. By their very nature, most rail yards are "wide spots" in the rail line. Thus, when they have been abandoned, the right of way has been used for other purposes, most often the former yards and associated rail corridors have been converted to other linear transportation uses, most notably commuter transit facilities and trackage, and public highways (expressways and limited access throughfares such as Interstate accessways).
The basic problem that confronts potential users of abandoned rail yards is that, while the yard is abandoned, usually the basic rail line is left, and in most cases, is still in active use. The railroad may have moved the location of the yard for several reasons, including enhanced intermodal accessibility, limited space expansion opportunities, and required "brownfield" remediation and associated clean-up activities.
Several abandoned rail yards come immediately to mind. These are:
1. CSX (Lakeland Yard, in Lakeland, FL.)
In this case, CSX constructed a new yard (Winston Yard) several miles SW of the City of Lakeland, and completely abandoned the older yard, except for a one-track main line that was realigned along one side of the yard. The abandoned yard was converted and marketed by CSX as an Industrial Park. As I recall, it has been 15 or more years since the conversion happened, and not one company has located in the Industrial Park. I don't know why, because the site is in a good location. Go figure!
2. CSX Potomac Yard, Alexandria, VA
This case is very close to VA TECH, and you should be able to get a lot of background information on the post-closure happenings of this yard in the Metro DC area. Frankly, I suspect that you are probably already familiar with this yard.
This yard was a former Richmond, Fredericksburg & Potomac RR yard that was closed somewhere around 5 or so years ago. My recollection is that there was a LOT of pressure for use of the yard space for conversion to high density commercial and residential uses, combined with commuter transit facilities. CSX gave into the local community pressures, and sold the yard, but retained a corridor for continued mainline trackage as an integral segment of their main N - S line between the Northeast and the South.
3. Jacksonville Union Terminal (Jacksonville, FL)
This was the largest railroad passenger station in the Southeast, and it was closed by Amtak in favor of relocating to a much smaller facility out on the NW edge of the downtown commercial district (well, it was further out than that; not necessarily in the boonies, but getting pretty close!)
The City of Jacksonville acquired the former Terminal building and transfored it into the major portion of a downtown convention center (Prime Osborn Convention Center), named after a former railroad executive. Most of the railroad tracks were retained, and are used by a major rail box and flatcar repair / leasing company as part of their repair facilities.
4. There are quite a few rail yards that have been abandoned in the rural coal-mining regions of Appalachia. In virtually every case that I am aware of, these yards are just sitting and waiting for some use. The same situation has happened with former phospate mining yards in central Florida, although in most cases, these yards have been removed and mined to extract the phosphate ore beneath them.
To complicate the issue, railroads have generally been reluctant to sell land that they own, unless there is a prospective buyer "knocking at the door".
Even yards that have been abandoned as standard purpose yards are often retained for such uses as rail car, equipment, and supplies storage purposes.
In other cases, the railroad has constructed offices and warehouses in the former yard space.
Most large railroad companies have property management divisions, that function like their own "realtors". I suggest that you start contacting these offices with CSX and NS. They are the people who market former railroad land for sale, and should be able to tell what uses former rail yards have been converted to, and also the potential uses that they are aware of in terms of pragmatic future opportunities.
Aurash, my gut feeling is that, in many cases, abandoned rail yards are located in the absolute worst parts of town, and the former yard and its surrounding areas are in an economic downslide, to the extent that no upscale industry or commercial company wants to take the risk of locating in the area. Perhaps the only other potential use of the property is for public housing projects, of which no one wants to place children and the elderly at risk in such unsafe conditions. Or, for the local government to undertake a radical revitalization project to transform the area into a totally different appearance and usage. The city of Chattanooga, TN undertook such a project in a really depressed, run-down warehousing and small railyard area along a portion of the riverfront on the north - northeast side of town. A really stunning transformation, with lots of shopping, dining and entertainment spots, in what is now a scenic riverfront setting.
So, in some cases, there does not appear to be an identified short-term use for many areas. But, with a vision and some scheming and dreaming, of which planners are renowned for, some great things can happen!
I will check through my information, and see if I can find other abandoned yards that you can check out in terms of their status.
Good luck! And, stay in touch, as I am very interested about how your "project" turns out, or if I can help along the way!