How to apply the initial strain on the ligament in Abaqus?

02 February 2020 1 9K Report

Dear All,

I'm trying to build a finite element model of the knee joint, but I'm having trouble applying the initial strain on the ligaments.

Data on initial strain is given in the literature, but I don't know how to apply the initial stress in ABAQUS, nor how to define the direction of the initial stress. I tried the predefined temperature field, but it didn't seem to work well.

Does anyone know how to set the initial strain and how to control the size and direction of the initial strain? Any answers will be appreciated. Thank you very much in advance.

Pavlo Pavliuchenko

Hello Peng Liang ,

initial strains could be added in Abaqus by several methods:

1) Using "Predefined Field": Load > Create Predefined Field > Hardening

Here you can choose the set of elements and apply initial equivalent plastic strains in the required direction (e.g. 11 - X, 22 - Y, 33 - Z etc.).

For more information read this:

http://abaqus.software.polimi.it/v2016/books/usb/pt07ch34s02aus118.html#usb-prc-pinitialcond-hardening

http://abaqus.software.polimi.it/v2016/books/key/ch09abk18.html#d0e73069

http://abaqus.software.polimi.it/v2016/books/key/ch09abk18.html#d0e74845

2) Using keyword *INITIAL CONDITIONS, TYPE=PLASTIC STRAIN

initial plastic strains could be defined.

For more information read this:

http://abaqus.software.polimi.it/v2016/books/usb/pt07ch34s02aus118.html#usb-prc-pinitialcond-pe

http://abaqus.software.polimi.it/v2016/books/key/ch09abk18.html#d0e73069

http://abaqus.software.polimi.it/v2016/books/key/ch09abk18.html#d0e75217

Sincerely,

Pavlo

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