.... The surface displacement is always inward and increases with time. On the other hand, the movement at depth is originally outward and it is reverted inward as time becomes large (Figure Sb). Figure Sc shows the variations of stresses with time. At surface, the radial and tangential stresses, or and 00, remain...

... are useful to give an interpretation to surface displacements evaluated by convergence measurements. Even though displacements caused by joint movement or cracks opening are not evaluated, the continuum solutions are valuable because it is obvious that unstable conditions may occur if the observed...