A 'ring' circuit has a couple of common uses. One use is a circuit fed from both ends. This is common in the UK, but illegal in the US because you effectively have unequal parallel conductors. The other use of the term is a circuit where one conductor is fed from one end, and the other conductor from the opposite end of a long run. This has the benefit of splitting the voltage drop evenly over all of the loads; useful for things like landscape lighting where you want all of the lights to be dimmed by the same amount. Neither of these approaches is relevant here.
Questions:
What are the actual load requirements? It won't be exactly 50A per drop; that is the rating of the drop, not the rating of whatever is plugged in.
What are the actual electrical requirements, eg. voltage, voltage tolerance, phase count, running current, starting current, etc?
How stable is the load. Is it constant or varying?
Will _all_ of the drops be used at the same time, or just transiently at different times?
Can loads with higher voltage tolerance be substituted?
Are you really trying to deliver 208V, or 208/120V?
What are the actual load requirements? Voltage, current, voltage tolerance, phase count, transient (startup) load, etc.? How stable is the load? Are these drops for lighting, or something related to moving the bridge?
Will _all_ of the drops be used at the same time, or just transiently at different times?
Can loads with higher voltage tolerance be substituted?
How did you calculate 1100 MCM cable? That seems overkill to me, but it is very easy to get that as a mathematically correct result if you have incorrect assumptions about your requirements.
-Jon