Force-Based Beam-Column Element
This command is used to construct a force beam element object, which is based on the non-iterative (or iterative) force formulation, and considers the spread of plasticity along the element.
| element forceBeamColumn $eleTag $iNode $jNode $numIntgrPts $secTag $transfTag <-mass $massDens> <-iter $maxIters $tol> |
Alternative command (kept for backward compatability) is:
| element nonlinearBeamColumn $eleTag $iNode $jNode $numIntgrPts $secTag $transfTag <-mass $massDens> <-iter $maxIters $tol> |
| $eleTag | unique element object tag |
| $iNode $jNode | end nodes |
| $numIntgrPts | number of integration points along the element. |
| $secTag | identifier for previously-defined section object |
| $transfTag | identifier for previously-defined coordinate-transformation (CrdTransf) object |
| $massDens | element mass density (per unit length), from which a lumped-mass matrix is formed (optional, default=0.0) |
| $maxIters | maximum number of iterations to undertake to satisfy element compatibility (optional, default=1) |
| $tol | tolerance for satisfaction of element compatibility (optional, default=10-16) |
NOTE:
The default integration along the element is based on Gauss-Lobatto quadrature rule (two integration points at the element ends).
The default element is prismatic, i.e. the beam is represented by the section model identified by $secTag at each integration point.
The -iter switch enables the iterative form of the flexibility formulation. Note that the iterative form can improve the rate of global convergence at the expense of more local element computation.
The valid queries to a nonlinear beam-column element when creating an ElementRecorder object are 'force,' 'stiffness,' and 'section $secNum secArg1 secArg2...' Where $secNum refers to the integration point whose data is to be output.
EXAMPLE:
element truss 1 2 4 5.5 9; # truss tag 1 between nodes 2 and 4 with area 5.5 and uses material 9
REFERENCES:
Neuenhofer, Ansgar, FC Filippou. Geometrically Nonlinear Flexibility-Based Frame Finite Element. ASCE Journal of Structural Engineering, Vol. 124, No. 6, June, 1998. ISSN 0733-9445/98/0006-0704-0711. Paper 16537. pp. 704-711.
Neuenhofer, Ansgar, FC Filippou. Evaluation of Nonlinear Frame Finite-Element Models. ASCE Journal of Structural Engineering, Vol. 123, No. 7, July, 1997. ISSN 0733-9445/97/0007-0958-0966. Paper No. 14157. pp. 958-966.
Neuenhofer, Ansgar, FC Filippou. ERRATA -- Geometrically Nonlinear Flexibility-Based Frame Finite Element. ASCE Journal of Structural Engineering, Vol. 124, No. 6, June, 1998. ISSN 0733-9445/98/0006-0704-0711. Paper 16537. pp. 704-711.
Taucer, Fabio F, E Spacone, FC Filippou. A Fiber Beam-Column Element for Seismic Response Analysis of Reinforced Concrete Structures. Report No. UCB/EERC-91/17. Earthquake Engineering Research Center, College of Engineering, University of California, Berkeley. December 1991.
Spacone, Enrico, V Ciampi, FC Filippou. A Beam Element for Seismic Damage Analysis. Report No. UCB/EERC-92/07. Earthquake Engineering Research Center, College of Engineering, University of California, Berkeley. August 1992.
Code Developed by: Micheal Scott, Oregon State Unievrsity