adding a soft stiffness matrix to the MPM problem
adding a soft stiffness matrix to the MPM problem

eaulisa/MyFEMuS,saikanth88/femus,giorgiobornia/femus,giorgiobornia/femus,saikanth88/femus,FeMTTU/femus,giorgiobornia/femus,FeMTTU/femus,FeMTTU/femus,saikanth88/femus,FeMTTU/femus,eaulisa/MyFEMuS,eaulisa/MyFEMuS,giorgiobornia/femus,saikanth88/femus