Using a cage on a persistent brooding bird is the kinder thing to do. Taking out of nest few times a day and blocking off nests can work if done in first few days but once the brooding is set they are in it for the long haul. They'll only leave the nest once a day to poop, eat and drink then back to the nest. It's hard on a hen to brood and if there are no fertile eggs to give or no desire to have more birds at this time the kind thing to do is to break her of the brood promptly and assuredly. The wire fold up kennels work great. Take the bottom tray out and elevate it on blocks. If the bottom wires have large openings (many do) then just turn the cage upside down. Leave the bird in with food and water for three days. No less or there is a chance she'll go back to brooding in a day and no more than three as it won't take more than three. In reality two days works most of the time but no need to chance it so go three. She'll bawk and generally be upset there is no nest for the first day. Second day not so bad and third day she'll be fine and not anxiously wanting out. Let her out end of third day to walk about with flock for few hours then go to roost with everyone else. Make sure she goes to roost that night, if back to nest put her back in cage for another day.
Brooding for a hen is to slowly waste away and without eggs hatching in 3 weeks will last longer. It's simply unhealthy. The kind thing to do is break her and deal with her angst for those few days she's in cage. I'd equate it to a broken arm. Sure it will heal, albeit crooked, all on it's own but the kind thing to do is cause the wee bit of pain to set it so it heals quicker.