Comparing with intact rock

the mechanical characteristics of non-persistent closed jointed rock mass have relatively large differences. A revised self-consistent method was used to consider the coupling between different damages

as a result

the compound constitutive model was deduced for non-persistent closed jointed rock mass under uniaxial compression. Based on the correlation between additional strain energy increment and damage strain energy release

the equivalent linear crack as jointed crack damage evolution trajectories was adopted

and then the additional strain energy for micromechanical damage

initial joints and jointed crack damage evolution was respectively calculated. In accordance to the Betti energy reciprocity theorem

a self-consistent method was introduced to account for the correlation among cracks

moreover

an approach for adding joints one by one was utilized to correct the traditional self-consistent method

in which the compound damage constitutive model was deduced in regard to different stages during uniaxial compression. The theoretical calculation results of the proposed model were compared with in-house experimental results in existing literature. The results show that: the theoretical calculation results are consistent with the experimental results. With the increase the number of joints

the initial elastic modulus and peak load show a downward trend

and the reducing value is in the same extent; there are significant impacts for the damage evolution of joints crack damage on the mechanical characteristics of the rock mass. The theoretical stress-strain curve and peak load for joint fissure damage evolution are consistent with in-house experimental results

which apparently verify the correctness and reasonability of the compound damage constitutive model.