A Damage Model for the Rockmass with Two Collinear Cracks Under Uniaxial Compression

Abstract

The rockmass with two collinear cracks is often encountered in practical engineering and how to calibrate the rockmass damage induced by these two collinear cracks attracts much attention. First of all, in view of the existing researches, a new damage calculation method of the rockmass with one single crack under uniaxial compression is proposed which can take into account the crack geometry, strength and deformation parameters at the same time. Especially the effect of the crack normal stiffness and shear stiffness on the rockmass damage is discussed in detail. Next, the damage model for the rockmass with two collinear cracks under uniaxial compression is proposed with Lemaitre strain equivalence hypothesis. A series of calculation examples indicates that the proposed model can perfectly reflect the effect of three kinds of crack parameters on the rockmass damage. With increasing the crack interval, the rockmass damage increases, while the rockmass damage decreases with increasing crack friction angle, normal stiffness and shear stiffness. Finally, the validity of the proposed model is verified with the experiment results.

Keywords: rockmass with two collinear cracks, uniaxial compression, damage model, crack deformation parameter, Lemaitre strain equivalence hypothesis