Truss element with Uniaxial materials

[mja165]

A truss element can be used with a uniaxial material like Elastic which can define either force-deformation or stress-strain relationship, so why this element can produce only force and deformation as output. How does it understand if my inputs for Elastic material were modulus or stiffness?

[vesna]

A uniaxial material assigned to truss element needs to be defined using stress-strain relationship (not force-deformation). In the manual I see the option for recording a material response. I guess you can also record stress and strain if you wanted.