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Dear iMechanica,





suppose you have a beam with a square cross-section, manufactured from an elastic-ideally plastic material.



Now apply a load that rises linearly in time, but is locally constant along the beam length. Upon sagging, the beam will develop a plastic zone beginning in the top and surface regions at mid-length.

This is the "straight" problem solved in Prager, Hodge: Theory of perfectly plastic solids, publisher: Springer

I want to work on delamination and cohesive zone model. I would also like to model this in Abaqus. I’ve read the material available there but it’s not adequate. I would like to know the concepts and fundamentals of the cohesive zone model and its implementation. Can anyone explain this? Please suggest some good literature/books on this for beginners.

Praveen.

Hi, i am trying to test a bulk metallc glass VUMAT with a simple compression test simulation. But since VUMAT is a Abaqus Explicit subroutine, that means I must set my compression simulation with setting of Abaqus Explicit right? So far I only have the experience in conducting compression test simualtion using ABAQUS Standard setting like static general step and surface-to-surface contact (standard). I don't know how to set up a simple compression test simulation with Abaqus Explicit settings, can anyone help me please?

Thanks and regards. 

J.C. Sobotka, R.H. Dodds: Steady crack growth in a thin, ductile plate under small-scale yielding conditions: Three-dimensional modelling., Engineering Fracture Mechanics, Vol. 78, 2011, pp. 343-363; J.C. Sobotka, R.H. Dodds: T-stress effects on steady crack growth in a thin, ductile plate under small-scale yielding conditions: Three-dimensional modelling., Engineering Fracture Mechanics, Vol. 78, 2011, pp. 1182-1200. 

To the discussion

Dear all,

      I want to model crack initiation and propagation for a user defined material, using Abaqus. When I try to model , I get the following error:

A MATERIAL PROPERTY THAT IS NOT ALLOWED WITH A USER MATERIAL HAS BEEN SPECIFIED

when I take out critical damage initiation, the model works fine; which means that it doesnt allow me to couple UMAT with crack initiation. Does anyone know how to handle this problem?

All the best,

         Panos

HI,
I am performing a non linear buckling analysis in ansys using shell 181 element. My geometry is made up of composite material and has a shell structure. The shell is subjected to torsion at one end so as to buckle throughout it length. the other end is fully constraint.
My problem is how to apply this torsional moment at the free end.
anybody please help me.