Being Russia, I'd be willing to guess that a large majority of those involved alcohol. Really makes me appreciate the training that most of our truck drivers need to have and our relatively rigorous enforcement of licensing and equipment safety inspections. Its one of the things that scares me about allowing Mexican trucks across the border. I've driven in Mexico, truck accidents like this are a way of life down there. No safety regs, very loose licensing.
I have seen the one where the wheels came off and hit the other cars, didn't hit mine though. It was on I-5 in Tacoma, wheel came off a log truck and jumped the jersey barriers into oncoming traffic. Smashed multiple cars but by some miracle, nobody was even seriously injured!
Seeing these in the past few years has made me want to get a dash cam though. I've been in two accidents this past year, neither we're my fault, but the other people claimed they were. Both lost, but a video would have made the process much quicker I think.