TBM Improvements – Innately Possibile

System to cut larger diameter tunnels without cutting the full circumference
To save spoil volume and energy.
Counter rotating cutters and installed railing.
Or \ drill clock position holes to weaken core with spacing to allow lower ribs to act as railing with spaced rollers.
Where materials are salvageable, utilize diamond cable cutters like quarries use with hubs pushed down and wet bore horizontal to feet cutters each 100 foot. Drill a couple extra center holes just under bottom, to hydraulically float out with pressurized water.