Elastoplastic damage modeling the mechanical behavior of rock-like materials considering confining pressure dependency

• An elastoplastic damage model is proposed to describe the mechanical behavior of concrete under extremely low to very high confining pressures.
• A special emphasize is put on the plastic pore collapse mechanism developed under high confining pressure.
• Damage mechanism is coupled with two plastic flow mechanisms in two different ways.
• A new numerical approach is proposed for the numerical implementation of the coupled elastoplastic damage model.

In this paper, the effect of confining pressure on the mechanical behavior of rock-like materials, such as concrete, is studied by using a coupled elastoplastic damage model. Damage mechanism is coupled, in different manners, with two plastic flow mechanisms: plastic shear mechanism developed under low confining pressure and plastic pore collapse mechanism observed under high confinement. The proposed model is applied to study a series of laboratory tests performed under extremely low to very high confining pressure, up to 650 MPa. The numerical predictions of proposed model are in good agreement with the experimental results.