The workspace
The left rail holds the drawing tools: Member, Select, Move, Supports, Force, Annotate and Erase. Groups such as Supports open their own sub-rail in place, and Back returns to the main tools.
The right rail holds panels and view: Properties, Results, Report, Grid, Fit and Dimensions. The analysis method sits at the top, next to the study name.
Choose the analysis
Equilibrium needs no material: a truss is solved by joint equilibrium and a frame by rigid-body equilibrium. Use it for statically determinate structures, as in a statics course.
Linear elastic solves any stable structure, determinate or not, by the direct stiffness method. Assign a material and a section to every member and you also get deflections, stresses and safety factors.
- If a structure is indeterminate, Equilibrium says so and suggests Linear elastic.
- If it is unstable, the status light names the part that can move.
Method of joints
For a truss solved by equilibrium, open the method of joints from the results. It lists the solution order and shows each joint's free-body diagram with its equations, step by step or all joints at once.
Unknown member forces are taken as tension, so a negative result means compression.
Frames, pins and rigid bodies
Members of a frame are welded at their nodes. Put a pin at a node to let its members turn freely; members with the same group number stay welded through the pin. The pins divide the frame into rigid bodies.
Equilibrium then gives the external reactions, the force at every pin and a free-body diagram for each body, including two-force members, as in frames and machines.
Drawing aids
Dimensions in Annotate add horizontal, vertical or aligned dimensions between two nodes. They are annotations: they follow the geometry and make the report clearer. Mirror, in a node's fan, copies the structure about a vertical or horizontal axis through that node in one step.