structure node apply command

Syntax

structure node apply keyword <range>

Primary keywords:

force    force-edge    moment    remove    system

Set generalized point loads for all nodes in the range. Generalized point loads consist of an applied force and an applied moment. Pressure loading can be applied to shell surfaces using the commands structure shell apply, structure geogrid apply, or structure liner apply. Distributed loads can be applied to beam and pile surfaces using the command structure beam apply or structure pile apply. The following keywords are available to define generalized point loads.

force v <keyword>

applied force vector (in terms of system defined by the system keyword). You can use one of the following keywords to modify how v is applied to the node:

add

the vector v is added to the existing applied force vector at that node

multiply

the vector v is multiplied to the existing applied force vector at that node in a component by component multiplication

force-edge v <add>

the vector v is added as a force-per-unit-length to all edges that join nodes in the range. The forces assigned due to the edge will be lumped at the two nodes, with each node receiving half. These forces are always in the global system and will set the nodes to the global system as with the structure node apply system global command.

These forces will overwrite the previous applied forces at the node; however, the add keyword can be given to add them to those currently present. Note that if this changes the system they were applied under, then the previous forces will not be corrected for the system change.

moment v (f in 2D) <keyword>

applied moment vector (value in 2D) (in terms of system defined by the system keyword). The following keywords can be used to modify how v (f in 2D) is applied to the node:

add

the vector v (f in 2D) is added to the existing applied moment vector at that node

multiply

the vector v (f in 2D) is multiplied to the existing applied moment vector at that node in a component by component multiplication

remove keyword

an applied condition remains in effect until it is removed with this command. The following keywords are available to choose which applied condition is removed:

force

removes any applied force condition on the node

moment

removes any applied moment condition on the node

system keyword

set the coordinate system in which the force and moment vectors are expressed. The default system is global. If the system is set to local, then in large-strain mode, the force and moment vectors will remain aligned with the local system as it rotates.

local
global