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Discrete loads on a beam model

For a grillage, 3D space frame, plate, shell and volume meshed models discrete loads may be assigned with the option "Project over an area" as described in the examples:

Help > Help Topics > Contents > Application Examples Manual (Bridge, Civil & Structural) > Simple Grillage

Help > Help Topics > Contents > Application Examples Manual (Bridge, Civil & Structural) > Simple Slab Deck

Note: For 3D solid models meshed with continuum elements (i.e volumes) discrete loads can be projected on the boundary surfaces of the volume by using the "Project over an area" option. For solids if the load is inside the volume, it can also be projected inside the volume by using the "projected into volume" option. 

Discrete loads are defined in 3D space and are applied to the model where they are projected onto a search area of surfaces (eg for a shell model), or of lines (eg for a grillage model).  Where the projected load crosses a 3D model more than once (multiple intersections), search areas may be used to control which surface the load is applied to. For more information regarding Search Areas, please see:

Help > Help Topics > Contents > Modeller Reference Manual > Chapter 5 : Attributes > Loading > Search Areas

For a line beam or frame model, discrete loads may be assigned with the option to "Project onto line".  

In this case, the Search Area is assigned to a line or lines.  The search area will be taken as in the plane of the line that the Search Area attribute is assigned to and normal to the load projection direction.  It is also bound (longitudinally) to an area defined perpendicular to the line and for it's extent. If the load is projected onto the line, but would be eccentric to the line, then moments will be induced and the effect of this load is calculated and applied as forces and moments at the line location.

Internal Beam loads on a beam model

Alternatively Internal Beam loads can be used to project load onto a line beam in 2D or 3D:

Attributes > Loading > Structural > Internal Beam Distributed
Attributes > Loading > Structural > Internal Beam Point

Internal beam distributed loads & Internal beam point loads may only be assigned to a specific line feature and may not "overhang" that feature. You may use a series of such load definitions to produce the loading that you wish.  Please see:

Help > Help Topics > Contents > Modeller Reference Manual > Chapter 5 : Attributes > Loading > Structural Loads > Internal Beam Loads (ELDS) 


More about point/ patch (discrete) loading

More about bridge loading

Basic checklist for a linear static model


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