(followed by on, and then the name of the person, посадить и закопать in Russian): to put someone in jail for life for a non-violent (but NOT victimless) crime like massive-scope corruption, and then kill them, or order their killing, in jail, under suspicious circumstances
to pour cement on someone, as a method, was formerly used by the KGB
Basically, code word for getting a guy hard. Associated with pouring cement, as cement becomes hard, (duh) and is useful to use when talking around family or innocent friends.
Girl: Hey, do you have and tips and tricks on helping me pour cement?
Girl 2: Girl, just get your man some Viagra, unless you wanna go try some weird natural remedy.