Displacement-Based Beam-Column Element
This command is used to construct a displacement beam element object, which is based on the displacement formulation, and considers the spread of plasticity along the element.
| element dispBeamColumn $eleTag $iNode $jNode $numIntgrPts $secTag $transfTag <-mass $massDens> <-iter $maxIters $tol> <-integration $intType> |
To change the sections along the element length, the following form of command may be used:
| element dispBeamColumn $eleTag $iNode $jNode $numIntgrPts -sections $secTag1 $secTag2 ... $transfTag <-mass $massDens> <-iter $maxIters $tol> <-integration $intType> |
| $eleTag | unique element object tag |
| $iNode $jNode | end nodes |
| $numIntgrPts | number of integration points along the element. |
| $secTag | identifier for previously-defined section object |
| $secTag1 $secTag2 ... | $numIntgrPts identifiers of 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) |
| $intType | numerical integration type, options are Lobotto, Legendre, Radau, NewtonCotes, Trapezoidal (optional, default= Lobotto) |
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,' and 'section $secNum secArg1 secArg2...' Where $secNum refers to the integration point whose data is to be output.
EXAMPLE:
element dispBeamColumn 1 2 4 5 8 9; # force beam column element added with tag 1 between nodes 2 and 4 that has 5 integration points, each using section 8, and the element uses geometric transformation 9
REFERENCES:
Code Developed by: Micheal Scott, Oregon State Unievrsity