Add an Edge Load as a force or moment distributed along an edge (for the Plate interface add it to boundaries). The load is defined in the given local coordinate system.

Select the coordinate system to use for specifying the load. From the Coordinate system list select from:

This setting is used in conjunction with Local edge system and Shell Local System. When the load is applied to an edge which is shared between boundaries, the coordinate system can be ambiguous. Select the boundary which should define the edge system. The default is Use face with lowest number.

Select a surface — Top Surface, Midsurface, or Bottom Surface. The default is that the load is applied at the midsurface. The effect of using another surface than the midsurface is twofold:

To place the load at another distance from the midsurface, select the Offset check box, and enter a value for the offset, zoffset.

If the material model is Section Stiffness, there may physically not be a well-defined top and bottom surface. If the load is applied at such a surface, the thickness value used to compute the load is taken from the settings in the Thickness and Offset node.

If a selected edge is connected to boundaries having different thicknesses, then the result of specifying Top Surface or Bottom Surface is not well defined.

Select a Load type — Force per unit length (the default), Force per unit area, or Total Force, or Resultant.

Select a Load type to define the moment load — Moment per unit length (the default) or Moment per unit area. Enter values or expressions for the components (x, y, z).

This section is available only in the Shell and Plate interfaces. It is not present when Resultant is selected as the Load type..

This section is only shown when Resultant has been selected as Load type. The distribution of the tractions over the boundaries is controlled by the settings here.

Select a Traction distribution — Beam or User defined.

When Beam is selected, the traction field approximately matches the stress distribution over a beam cross section.

For User Defined, you can write expressions for the traction distributions. Enter expressions for the six dimensionless vector-valued traction distribution functions, q1, q2, q3, q4, q5, and q6. Usually, the local coordinates of the loaded region would be used for this purpose, but there is no limitation on the form of the functions. The built-in variables for the local coordinates are named <physics_tag>.<load_tag>.x2 and <phys_tag>.<load_tag>.x3, for example shell.el1.x2. The default value is the distribution that is used when the option Beam is selected.

The local coordinates of the boundary, x2 and x3, are defined in the following way:

When User Defined is selected, you can also select a Weight function — None, Circular, or User Defined. This function acts as a multiplier to the traction distribution functions. When None is selected, the weight function w = 1. For Circular, enter a radius rw of a circle, outside of which no load is applied (w = 0). Inside the circle, w = 1. For User Defined, enter a weighting expression. Usually, the built-in local coordinates of the loaded region would be used for this purpose, but there is no limitation on the form of the function. A time- or parameter-dependent function can, for example, be used to model a moving load.

where the coefficients ci are chosen so that the given force and moment resultants are obtained.

This section is only shown when Resultant has been selected as Load type. If the resultant force is applied in a symmetry or antisymmetry plane, this fact needs to be taken into account when creating the corresponding traction field.

Select a symmetry type — None, Symmetry, or Antisymmetry. When one of the types of symmetry is chosen, specify the symmetry plane by entering a Normal Vector, nsym, and a Point, xsym, located in the plane.

To display this section, click the Show More Options button () and select Advanced Physics Options in the Show More Options dialog box.

If you are performing a linear buckling analysis with a combination of live and dead loads, select the Treat as dead load check box to indicate that the load contributions from this node are constant. The default is that a load is proportional to the load factor.

Physics tab with Shell or Membrane selected:

Physics tab with Plate selected: