Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

  • Congratulations TugboatEng on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

What modulus to use - TANGENT OR SEECANT modulus ?

Status
Not open for further replies.

SAK123

Structural
Joined
Oct 1, 2006
Messages
23
Location
DE
Is there any guidelines on when the tangent and when the secant modulus should be used in modeling ? I am modeling fabric material so the behavior is non-linear but several people at my office think tangent modulus should be used whereas others think secant modulus should be used in modeling behavior.

I searched the web and nothing provides direction on what is more suitable for FEA non-linear fabric material behavior.

Thanks for any input.

Regards -
 
What type of analysis are you running (stress, vibration, bucking, ...), and what type of results do you want to obtain (stress, displacement, modes, ....)?

Is this bare fabric? composite?
 
I am running a static stress analysis interested in stresses with a side interest in displacements. The element is membrane type - i.e. no bending stress. Material is not modeled as a composite - it is modeled as an Orthotropic type.
 
I don't think you should use either "modulus". For a nonlinear analysis you should input the stress-strain curve for the material. If you want to predict failure you will need to select a failure criteria and input the appropriate material strength parameters.
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor

Back
Top