Triangle#

This command is used to construct a constant strain triangular element (Tri31) which uses three nodes and one integration points.

model.element("Tri31", tag, nodes, section[, pressure, rho, b1, b2])
Parameters:

  • tag – unique element object tag

  • nodes – a list of three element nodes in counter-clockwise order

  • section –

    tuple or int. If int, it is the tag of a previously defined section object. If tuple, it is a tuple of the form (thick, type, material) where

    thick float

    element thickness

    type |str|

    string representing material behavior. The type parameter can be either 'PlaneStrain' or 'PlaneStress'

    material integer

    tag of an General Materials

  • pressure – surface pressure (optional, default = 0.0)

  • rho – element mass density (per unit volume) from which a lumped element mass matrix is computed (optional, default=0.0)

  • b1 – constant body forces defined in the domain (optional, default=0.0)

  • b2 – constant body forces defined in the domain (optional, default=0.0)

The valid queries to a Tri31 element when creating an ElementRecorder object are

  1. "forces",

  2. "stresses", and

  3. "material $mat args..." Where $mat refers to the material object at the integration point corresponding to the node numbers in the domain.