No compression for spring element in Abaqus

[master101]

Hi,I am trying to simulate ligament as a spring element (wire) in Abaqus. But problem is ligament has no compression. How can I apply "no compression" if I design it as a spring or I can make sure that my spring element is not taking any compression. From history output of spring element, it seems that it got some negative reaction (CTF1) force. Does it mean compressive force? If anyone know, please response.

Thanks!!

 

[bkal]

You need to define a non-linear spring, i.e. define the points on load vs. displacement curve, which should have zero force for compression (negative strain). Figure 31.1.1–1 in ABAQUS manual (version 11 of the manual) explains in more details.

 

[master101]

Hi bkal, thanks for your suggestion.

I solved assuming spring as nonlinear. There are total 4 springs. But output graph shows that all springs displacement are negative though it looks from visualization that 1 or 2 spring is probably extending. Also, surprisingly, for one of spring, when displacement is negative, it gives a small value of CTF.

Any idea why this is happening? Why all springs displacement are negative? Thanks again.

 

[bkal]

Have you checked orientation of the springs (which is the first and which is the second node in the spring definition), read carefully how is it relative displacement calculated.

 

[Israrkhan123]

Hello,
Could any body show me the way show to apply ( connector damage evolution ) between concrete and rebar in pull out test.
Thank you in advance,