Incremental Plastic Strains, ASME Local Failure Assessment

[Doodler3D]

Referencing thread727-483933, pertinent to ASME BPVC Section VIII, Div. 2 Part 5.3.3, protection against local collapse, elastic-plastic method

At any given iteration, the "incremental" equivalent plastic strain is used to verify the strain limit. However, NLEPEQ or EPPLEQV_RST (Ansys Workbench) are nodal and elemental accumulated plastic strains. Is it appropriate to use NLEPEQ or EPPLEQV at non-averaged nodal integration points?

Thank you.

 

[NRP99]

Before going into details, take a look at these discussions about local failure - thread794-489573, thread794-486888.

First understand the failure mode and then you can understand which quantity is appropriate for checking criteria. Equivalent plastic strain at nodes or at integration points is sufficient.

 

[Doodler3D]

Thank you Nikhil, the LinkedIn post was lucidly written. While I can understand the theory behind mechanism of the local collapse, the implementation in the code and PTB-1 is rather ambiguous. I have ordered TGS4s papers and hopefully the implementation will be clearer.