I've been having the same problem.
I just bought the game today, played about 2 hours, and now it crashes about every 10 minutes.
I reported this on Steam and someone suggested that it could be a memory leak. I don't know where it would be leaking to or from. It's dry around my computer, so that can't be it. I have 16 gigs of ram and no mods.
I'm just starting the game today on career mode, so I don't even have in game assets.