Since the Mishkan was portable, it was meant to be assembled and disassembled on an as-needed basis. Disassembling is the melacha of soseir, though the word more literally means “demolishing.” Soseir is the reciprocal melacha of boneh and, as we have stated, all of the “destructive” melachos were performed for a constructive purpose. (In this case, the Mishkan was disassembled so that it could later be re-assembled elsewhere.)
Even today, demolishing for the purpose of building is common. It doesn’t even have to be something major, like tearing down a supermarket to make room for a parking lot. Taking anything apart with the intention of using its component parts would fulfill this criterion and would be considered soseir at the Biblical level. (Destroying for a purely destructive purpose is forbidden rabbinically, so don’t go around knocking down any walls on Shabbos, even if you don’t intend to rebuild in that spot or use the bricks elsewhere!)
As is typically the case with reciprocal melachos, a good rule of thumb is that if you can’t put it together because of boneh, you can’t take it apart because of soseir.
This is just an introduction to the concepts of the melacha of soseir; it is not a substitute for a full study of the halachos.