Some internal reinforcement for the bottom 3 ring segments using a few red "antiques" left over from my childhood collection...
The 1x6 black plates are helpful on their own to pull the individual sections together but the hinge plates really beef-up the joints between sections (otherwise it's down to one stud).
The vertical plates have hollow-studs and are on a half-stud offset on rear pins of the 1x6 plates. The rings were super-fragile without these in place and kept falling apart when I was installing them. Now only the connections to the top section are un-reinforced. The top section is built on the frame, then this is connected to it.
This is the back ring. The front one has black versions of the hinge-plates. Yay ancient spares-bin!
Unlike the other tweaks I've made as I build it, since I wasn't sure if this would work digitally, I did not reflect this in my LDD version.