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  1. InvariantL

    Pure Traction BC's in Abaqus Help!!

    Try *STATIC, STABILIZE instead of just *STATIC for your procedure. In Abaqus/CAE you indicate this by clicking a button on the panel where you configure the step. Alternatively you could just use a displacement boundary condition at one end instead of the traction. Make sure you only constrain...
  2. InvariantL

    ***WARNING: EXCESSIVE DISTORTION AT A TOTAL OF 97 INTEGRATION POINTS

    When I get these multiple problems, usually my mistake is that I haven't been careful in entering the data for the yield point and plastic properties of the material. I would double check it and make sure you didn't use the wrong units, omit a factor of 10, etc. These errors can make the...
  3. InvariantL

    Elastic Plastic Analysis

    A linear static analysis should work, but for a unidirectional lamina, hand calculations (rule of mixtures or Halpin-Tsai equations) are usually sufficient. What are the constituent materials and the reinforcement geometry? You say you have plastic properties for the constituents, but it's...
  4. InvariantL

    Contact between 2D beam and Shell

    Unless you are interested in the detailed interactions (including possible slippage) between the soil and the nails, you could use one of the options in Abaqus Analysis Manual section 2.2.3. You can define reinforcements in a shell or membrane, then embed the reinforced shell in a solid...
  5. InvariantL

    Help needed in Abaqus FEA

    "Often, when increment sizes reduce too much, the displacement corrections are of the same order of size as displacements themselves, which prevents convergence." Yeah! I forgot about that though I've observed it many times and never quite understood it. It's surprising that you hit the...
  6. InvariantL

    Error during anisotropic

    Based on your description I'm guessing that CAE is generating a *SHELL GENERAL SECTION, COMPOSITE card to define the properties. Look at that line(s) in your input file to make sure a material with a reasonable stiffness is being assigned to each layer. www.invariantlabs.com
  7. InvariantL

    Error during anisotropic

    Singular means that in at least one direction, there is no resistance to force and the displacement solution "blows up". I assume you entered some nonzero stiffness values in the matrix for the thin film. If the film is much different in stiffness than the substrate or other materials in the...
  8. InvariantL

    Help needed in Abaqus FEA

    I don't think reducing the increment size is going to help here - the solver has already automatically reduced it to 3.906e-3 and it still doesn't converge. There are a thousand reasons this can happen, but you might not have adequately constrained the structure, i.e. it might be free to spin...
  9. InvariantL

    Marlow Model

    Alex, Are you using first-order or second-order tets? First-order tets are fully integrated and therefore don't hourglass, but they don't resolve the stress very well and can cause lack of convergence. The "regular" second-order tets (C3D10 or C3D10H) are more accurate and don't hourglass, but...
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