The question was probably answered but the search returned nothing.

How to make mines respawn in a respawning zone once exploded or disarmed during a previous visit ? Creatures respawn but not the mines. The new dwellers should've placed traps and mines again, isn't it ?

Reset the cell? Only that will reset all the containers too.

You could make a script that places the mines there after a certain number of days. Make it run once on a condition that another mine has exploded. This will require custom mines to accomplish. Make sure to set the ownership of the mines so that they don't blow up the enemies in the cell.

However, no cell in the game ever reset's it's traps and mines. In fact, this trick can be used to take out enemies after they respawn if you plant mines before you leave....