Abstract:

The fault zone rock foundation is common in geologic structure. The 3-D analysis of progressive failure of rock slopes including fault zone is very difficult. An interface element style has been put forward according to distribution of fault zone in rock mass to simulate the rock and fault zone in arch-dam zone. The shape function and elastic matrix have been given. And the entire fault zone in the location, 22-fault zone, has been simulated. The Mohr-Coulomb criterion has been selected as yield criterion in plastic analysis. The stochastic distribution of rock and fault zone has been conceded. Cracking analysis has been used to search for critical slip surface based on gradually cracking theory and credibility theory and elastoplasticity theory. Then the probability of slip has been obtained according to reliability theory. Through three thousand times finite element calculation, the location of slip surface, the form of s slip surface and the sequence of cracking have been obtained; the conclusion of the mode of progressive failure of rock slope including fault zone can be drawn as: the failure began at fault zone. With the fault zone cracking, the stress states of slope deteriorate. Some rock layer began changer to plank with different support, then the rock layer began crack, and then the slope began slip. At last the slopes collapse with one or more failure steps.

Key words: 3-D progressive failure, rock slopes, fault zone, elastoplasticity, reliability