To download free PEB structure design software, follow these steps:

MBS is one of the few software packages built specifically for PEB (portal frames, multi-span buildings, lean-to structures). The free demo version allows you to model up to 5 members and print reports (watermarked). It automates haunches, tapered segments, apex connections, and crane beams.

When selecting PEB structure design software, look for the following features:

AutoCAD is free for students so Planswiift may have something as well. Autodesk Revit