ForceFrame

Fig. 1: Section discretization of the ForceFrame element. Rendered with veux.

Two-node force formulation for 3D frames. [1] [2].

Python

Model.element("ForceFrame", tag, nodes, *, section, transform, **options)

Parameters:

tag: integer

unique Element tag

nodes: tuple

tuple of two Node tags

section: xara.FrameSection

Section object to be created at the element Gauss points.

transform: integer

identifier for previously-defined frame transformation

Optional:

integration

identifier for previously-defined integration rule.

ForceFrame is an extended implementation of the OpenSees forceBeamColumn element, which is based on the formulations described by [1], [2], and [3]. In a model with 7 degrees of freedom, the element incorporates nonuniform warping effects as described by [5].

Output

The valid eleResponse queries to this element are:

• "force".

• "section": Make a query to a specific section along the element:

  model.eleResponse(element, "section", section, *section-args)
  

Examples

Steel Shear Link

../../../../../examples/frames/frame-2007.html

References

[1] (1,2)

Spacone, E., V. Ciampi, and F. C. Filippou (1996). “Mixed Formulation of Nonlinear Beam Finite Element.” Computers and Structures, 58(1):71-83.

[2] (1,2)

Lee, C.‐L., and F. C. Filippou. “Frame Elements with Mixed Formulation for Singular Section Response.” International Journal for Numerical Methods in Engineering 78, no. 11 (June 11, 2009): 1320–44. https://doi.org/10.1002/nme.2531.

[3]

18. 12. Taylor, F. C. Filippou, A. Saritas, and F. Auricchio, “A mixed finite element method for beam and frame problems,” Computational Mechanics, vol. 31, no. 1–2, pp. 192–203, May 2003, doi: 10.1007/s00466-003-0410-y.

[5]

Perez, C. M. “Nonlinear Modeling of Frame Members for Rapid Infrastructure Assessment.” Ph.D., University of California, Berkeley, 2026.

Code developed by: Claudio M. Perez, fcf, Michael H. Scott, fmk