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@Aslinn

It looks like you clicked on the Solution branch of the outline.

You need to click on the Static Structural branch of the outline, which has a different ribbon. In a narrow window, they are under the Tools button.

Hi @jaboust

In details of command object, you can toggle on the boxes next to Arg1, Arg2 etc to create input parameters:

Your command object can then use ARG1, ARG2 etc as variables:

Example:

nsel,s,loc,x,(ARG1/2)

In WB project page, double click on parameter set. Then set ARG1 equal to length parameter you have defined/imported from CAD

Example:

In the example above, I am setting P11 (this is ARG1) equal to P8(length parameter) divided by 1 unit to make P11 dimensionless

@Rameez_ul_Haq

If a Face has 64 nodes on it, then there will be 64 springs to ground created for the elastic support.

If you add a spring to ground to the same face, there will be one spring created with a rigid spider to the face. However, the spider can be changed to deformable.

The elastic support is always perpendicular to the face. A spring attached to a face can go in any direction.

The elastic support spring rate is N/mm^3 while the spring rate is N/mm

The spring can have damping, but the elastic support cannot.

The spring can have a preload, but the elastic support cannot.

The spring can be defined between two points, so it has a length. The elastic support is only defined as a spring rate.

@markfea

I often see the Warning on properly constrained models. You can ignore the warning if the results look reasonable.

The two Frictionless Supports on the radial cut faces create an overall radial constraint on the whole sector because they have an angle between them.

Most materials fail in Tension at a much lower level of stress than Compression. The highest level of tension is shown by Max Principal stress. The highest level of compression is shown by the Min Principal stress. The directions of these two stresses are orthogonal.

A true truss structure is assembled using pins at the ends of each strut. The pins prevent any bending loads from entering the strut. Only axial forces can enter the strut. Some bridges have struts welded to plates at the joints so that bending loads could enter, but then it is no longer a true truss structure.

In a true truss structure, you can compute by hand the tension and compression in each strut from the applied loads and the reaction forces at the supports. In the figure you show, the applied load P is vertical, so Ha = 0. Once you weld the joints, it is much more difficult to compute the stress in each strut by hand because bending will be allowed, so a FE model would be used to compute the solution instead.

While exceeding the strength of the material is a failure mode for struts in tension, there is an additional failure mode for long slender struts in compression: buckling. ANSYS can do a linear Eigenvalue Buckling analysis to compute the critical buckling load.