A Nonlinear Elastic-hardening Plastic Cap Model

In this papar, the rock behavior before yielding is analyzed by using the theories of continuum mechanics. The nonlinearly elastic constitutive equation of rock medium is derived and compared satisfactorily with the available experimental data. Moreover, the substitution of linearly elastic hypothesis used in the conventional cap model with the nonlinearly elastic one leads to develop a new nonlinearly elastic-hardening plastic cap model as presented herein.