Statically Determinate Beam and Axle Calculation

In this topic the phrase axle is used instead of beam, but the same principles apply to beam calculations, as well.

In addition to beam calculation parameters, in axle calculations it is possible to enter several different cross sections and also a normal force and a torsion, which are constant over the axle's length.

If the the axle's cross section varies, you must point each cross section’s end point starting from the axle’s left end. Don't point the last cross section's end point (the right end of the axle), but select the function Confirm.

After pointing each cross section end point, enter the cross section quantities by selecting a profile. Cross section quantities are calculated based on the given diameter. Select a material and a notch sensitivity factor in the opened window. The notch sensitivity factor can also be calculated for a material by selecting one that has Neuber's constant instead of a notch sensitivity factor. The program also asks for the notch radius the notch angle.

The program ask for the fatigue notch factor for different load types: bending, normal force and torsion. If a certain load type is not needed, the corresponding fatigue notch factor is also not needed. You can find the the fatigue notch factor from source literature.

If there are a notches in the axis, in which the cross section only changes locally, select Local Notch Effect and click its position on the axle. Then select the notch sensitivity factor, if it's not entered before, and enter the fatigue notch factors like in the cross section points. The cross section is selected in the same way by entering the axle's minimum diameter at the position of the notch. A local notch is ignored when defining torsion or deflection diagrams, but is taken into account only when calculating stresses.

Along with all loads, it is possible to edit the parameters of the cross sections, the related notch factors and of the local notches by selecting Check loads. The positions cannot be changed.

You can select line drawing on or off by selecting Line draw. The twist, deflection, bending moment and bending stress diagrams are drawn as lines in the drawing. These can be printed or saved when exiting the software unlike diagrams displayed as points.

You can define the calculation accuracy by selecting Counting points. The default value for dividing the axle is into 100 parts.

In the calculation results both the torsion and the reduced stress (average stress +- amplitude) are taken into account. Normal stress caused by normal forces and torsion are included in the reduced stress's average stress. Amplitude is caused by the bending which changes direction as the axle rotates.