Stability analysis of a cave excavated in granular cohesionless material

The paper presents an analysis of the long-term stability of a large unsupported cave excavated in granular cohesionless material in Ficulle, Italy. The stability of the cave arises from a ‘cohesive’ term in the shear strength criterion and this paper investigates the source of this cohesive term. Contrary to expectations, the material appeared to be granular (cohesionless) at the touch. The investigation started by determining whether the...