Cohesive elements

Hi everybody,

have you ever tried to implement in Abaqus periodic boundary conditions?

I am doing this. Particularly, I am applying PBC to unit cells constituted of a clay particle in an epoxy matrix.

When I apply PBC in case of transverse shear, I have convergence problems using Abaqus standard,

so I have to use an algorithm of stabilization but because of this one

I have to renounce to the stress continuity between opposite boundaries of the unit cell.

Do you think this is normal or I am doing some mistakes?

Hi,

I am working a long time on using cohesive elements in ABAQUS but up to now my efforts have be unsucessful.

I want to use of cohesive elements with the following paramters:

Damage initiation: Normal stres= 1.9 MPa, shear stress= 6.2 MPa 

Damage evolution:  Mode I fracture energy= 0.5307, Mode II farcture energy= 0.6623

Could any body kindly let me know that what would be my model E/Knn, E/Kss parameters?

Thank you,

Parisa