Nice work! You might want to consider some pyramid ramps at the base, so zombies approaching from angles other than head-on won't stop and beat the ramp down.
I built something like this but once demolishers spawn (for me it was day 28) they destroy everything so fast. Is there any way to deal with them easily?
Spread out your electric fences and as bfelthias says use steel. Personally I headshot them when they are stunned by electric fences. Demolishers on day 28 is rough. RU-vid deleted my last reply for some reason.
If you want to repair it in a middle of a horde night, you could put a ladder through the floor that goes most of the way down behind the blades. Replace some the blocks near the blade trapes with hatches. Be careful not to give them access and use strong hatches etc. I just repair it after hordes nights by using ladder of the middle to reach the blades.
