All axes, the global axis and local (structural) axes, are colour indicated according to the RGB (Red, Green and Blue) scheme throughout the PLAXIS Input and Output program:

• Red indicates the first axis: the x-axis for the global axes, and axis-1 for a local axis
• Green indicated the second axis: the y-axis for the global axes, and axis-2 for a local axis
• Blue is for the third axis (3D only): the z-axis for the global axes, and axis-3 for a local axis (e.g. surfaces)

Specifically for PLAXIS 3D, you can visualise the local axes in Input program under Options > Show local axes... and select any of the relevant option (multi-select possible).

Figure 1: Local axis for plates and the global axes (right) in PLAXIS 3D Input

 

For PLAXIS 2D and PLAXIS 3D Output programs, you can visualise the local axes after selecting a structural object and toggling them on via the View > Local axes menu option.
Note that the local axes will be visualised when applicable in the relevant results plots, e.g., axial forces, local displacements, etc.

Figure 2: Local axis for plates and the global axes (left) in PLAXIS 2D Output

Figure 3: Local axis for plates and the global axes (right) in PLAXIS 3D Output