CaptM says 200. The map I saw seemed to indicate 30-40. I’ll assume CM is from Morgantown WV and has first hand knowledge of the campus.
I was on the faculty at VT for 13 years before moving to WVU a couple of years ago.
This link gives a high detail campus map that shows about 120 major buildings in the central part of the main campus:
http://www.vt.edu/where_we_are/maps/documents/vt_main_map.pdf
This does not include the many small buildings (houses converted to offices near campus, greenhouses), the scores of buildings on the adjacent research farms, the 25 or so large buildings in the adjacent research park, or the dozens of lab buildings in outlying areas. It’s a big place and there’s no way that security personnel could instally secure every part of campus.