Unidirectional Non-Linear Tab

If nonlinear longitudinal shear behavior is desired in an analysis with Helius PFA, data must be entered in the Non-Linear tab.

M - Longitudinal Shear Data (controls pre-failure behavior)

This field contains experimental lamina longitudinal shear data used in Helius PFA to model nonlinearity under longitudinal shear loading. The data provided must slightly exceed the supplied lamina longitudinal shear strength value (+S12). The units of stress must be consistent with the unit set chosen. The units of strain are dimensionless and the values must be determined from the engineering definition of shear strain.

Suppose the data in the table below is provided as experimentally measured longitudinal shear data. The data would be entered into the GUI as shown.

As a quick check that the stress-strain data is entered correctly, you have the option of clicking on the "Show Curve" button. It will result in the plot shown below.