Johnson holmquist damage model

Dear professionals,

I'm self-developing explicit 3-D hybrid FEM/DEM code using GPGPU for my research regarding Penetration of projectile into rock.

In the code, I'm incorporating JH-2(Johnson holmquist) constitutive model.

Although this constitutive mode has been implemented in LS-DYNA and Abacus Explicit, some implementation detail has not been geven in exsisting literature. I mean, I reviewed several literature but I only found a flowchart of implementation of JH2 from Table 1 in