Recently, I indulged myself into the progressive damage simulation of composite materials. I firstly used the USDFLS to create several fields to define certain kinds of damage, such as fiber crack, matrix crack, shear damage and delamination. One curious thing that I experienced into this is that ABAQUS/Standard informed me that "Stiffness defined by engineering constants is not physically reasonable. Check choice of poisson's ratios". I checked the data and changed some to comply with the rules of the transversely isotropic materials and the program proceeded.
But it was on the cost of breaking the principle of material property progressive damage degradation!!!
I wanna propose an question, is there any way in USDFLS to model progressive damage in composite material?
Is there any other way like UMAT to model progressive damage in composite material?