What is the main operational principle behind a Slurry TBM's face support system?

The main operational principle behind a Slurry TBM's face support system is to maintain face stability by applying a controlled slurry pressure to the excavation face, counteracting the earth and water pressures. This prevents collapse or excessive deformation of the ground ahead of the TBM. A slurry, typically a mixture of bentonite clay and water or other specialized fluids, is pumped into the excavation chamber at the TBM face. The slurry permeates into the surrounding soil, forming a filter ca....