Hows does Abaqus calculate the Stress Intensity Factors?

[uwcomposites]

Dear All,

I have been calculating Stress Intensity Factors with Abaqus and they compare very closely with close form solutions, for different mesh densities and element types. The question I have is: would anyone know which method does Abaqus use to calculate Ks? The Abaqus Theory Guide only describes how the J-Integral is calculated.

Thank you in advance for your help,

-Francesco

 

[carthago]

..just of curiosity , are you stress intensities in line with for instance with ones in API 579 ? how do they compare with published values ?
..This standards has an extensive literature regarding stress intensities and their application for fitness for service purposes.

take care and thanks

 

[uwcomposites]

I have modeled a Compact Tension specimen and the calculated KI matches the value you can calculate using the close form solution, for instance from the Anderson's Fracture Mechanics: Fundamental and Applications book.

Anyway, I have answered my original question. Unlike other codes, Abaqus calculates the stress intensity factors from the J-integral, so it calculates the J-integral first.