chain stiffness

cingolo

Good afternoon all
How i can simulate the chain stiffness on truss member (only on tensile element)? for example a lifting tool by chain.

Thank you

Best regards

cwharpe

A few days since your post, maybe this helps your solution?:

The Tension-Only Line2 element requires inputs of just Young's modulus and the cross-sectional area. The stiffness, k=EA/L, is calculated internally considering the length between the two end-nodes.

While Tension-Only is better for cables, chains, ropes, you could also use springs with the same k-value, although in practice you would be wary of any spring "chain" that passed from tension into compression.

An interesting thing I learned from websites of engineering simulation tools for marine environments (ProteusDS, Orcina) was the way they derived the (E*A) stiffness. They didn't use Young's Modulus for E! Rather, they use a value just over one-fourth of Young [E~54.4 GPa], which likely was derived from any number of empirical/ analytical Load vs. displacement plots. Also the Area they use equals twice the cross-sectional area of one vertical bar within the chain link.

Finally, I remember seeing somewhere stiffness values published within chain catalog tables, so maybe you'll get a direct result?

Here are the web-links for the chain-modeling info.:

www.orcina.com/webhelp/OrcaFlex/Content/html/Chain,Axialandbendingstiffness.htm
www.orcina.com/webhelp/OrcaFlex/Content/html/Chain,Mechanicalproperties.htm
documentation.dsaocean.com/tutorials/Tutorials/PDS-AAR.html

Cheers.

EDIT:5/7/25. You don't say anything about the type of chain used. I have assumed studless anchor/load chain. To be more concise, the derived Modulus for anchor chain varies somewhat as a function of [diameter, alloy grade, et.al.] See pic.