That, or when the ship was built with engines capable of delivering 4G they designed the rings to handle it. You could tether the rings to the outside of the s

That, or when the ship was built with engines capable of delivering 4G they designed the rings to handle it. You could tether the rings to the outside of the ship (towards the nose) like a suspension bridge to support them during high thrust periods. Perhaps spinning the rings requires the tethers to be removed, or perhaps the rings must not be spinning while the engine thrust above 0.5G (because high trust locks the bearings of the rings).