Brittle Elastoplastic Damage Constitutive Model for Jointed Rockmasses and Computation Concerning Bolt-Reinforcement

Abstract

The present paper puts forward a 3D brittle elastoplastic damage fracture constitutive model (BEPDFC model) for jointed rockmass, which is established according to the evolution equation for energy damage of rock fissures, the generalized orthogonal flow rule and the conformability conditions of plastic damage. On the basis of this constitutive model, a cylindrical damage rock-bolt element model (CDRBE model) is proposed to simulate the reinforcing effect of bolts. Finally, the proposed models are applied to the stability analysis of the high slopes of ship lock of Three Gorges Project being under construction. The 3D nonlinear FEM analysis on the jointed rockmass of high slopes gives satisfactory results.

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