3.1.10.87. VS3D4 Element

This command constructs a four-node quadrilateral viscous-spring boundary element for absorbing and transmitting outgoing waves at solid domain boundaries. The element supports sensitivity analysis. Use with -ndm 3 -ndf 3.

element VS3D4 $eleTag $iNode $jNode $kNode $lNode $E $G $rho $R <$alphaN $alphaT>

Argument	Type	Description
$eleTag	integer	unique element tag
$iNode $jNode $kNode $lNode	integer	four boundary nodes in counter-clockwise order
$E	float	Young’s modulus of the adjacent solid medium
$G	float	shear modulus of the adjacent solid medium
$rho	float	mass density (default 1.0)
$R	float	distance from the boundary to the domain of interest (default 1.0)
$alphaN	float	normal-wave correction factor (default 1.33)
$alphaT	float	tangential-wave correction factor (default 0.67)

Note

1. Intended for dam-foundation and other 3D wave-propagation models with artificial boundaries.

2. Valid Element Recorder queries include force and stiffness.

Example

1. Tcl Code

element VS3D4 1 1 2 3 4 3.0e10 1.2e10 2400.0 50.0

2. Python Code

element('VS3D4', 1, 1, 2, 3, 4, 3.0e10, 1.2e10, 2400.0, 50.0)

Code developed by: Quan Gu, Yichao Gao, and Zhijian Qiu, Xiamen University