The stresses at each point along the stress line are obtained by interpolating the unique nodal stress values using the averaging criteria defined in the Result Options dialog box (for more information on specifying the averaging criteria, see Controlling result averaging, Section 24.5.6). ABAQUS/CAE uses a local coordinate system that is defined by the stress line to obtain the stress results. The local x-axis lies along the stress line; it originates at the first point on the stress line and is defined by the vector connecting the first and second points on the stress line. The local y- and z-axes are determined as follows:
For two-dimensional models:
The local y-axis is obtained by vector multiplication of the global z-axis with the local x-axis. The local z-axis is the same as the global z-axis.
For three-dimensional models:
If the local x-axis is parallel to the global y-axis:
If the positive local x-axis lies along the positive global y-axis, the local y-axis will be the negative of the global x-axis. If the positive local x-axis lies along the negative global y-axis, the local y-axis will be the global x-axis. The local z-axis is obtained by vector multiplication of the local x-axis and the local y-axis.
If the local x-axis is not parallel to the global y-axis:
The local z-axis is obtained by vector multiplication of the local x-axis and the global y-axis. The local y-axis is obtained by vector multiplication of the local z-axis and the local x-axis.
The stresses are then linearized. The stress linearization calculations differ for nonaxisymmetric and axisymmetric models. For more information on these calculations, see Stress linearization, Section 2.17.1 of the ABAQUS Theory Manual.
ABAQUS displays the resulting linearized stresses in the form of an X–Y plot. Three separate curves are presented for each stress component representing the following:
The actual stress distribution across the stress line.
The linearized membrane stress.
The sum of the linearized membrane stress and the linearized bending stresses.