Modelling

Coordinates are global X, Y (horizontal) and Z up. The model is stored in kip and inches; every field shows and accepts the current display units (Units).

Nodes #

Node tool (N): click on the work plane; the cursor snaps to the grid, nodes, midpoints and intersections. Type coordinates for an exact point.
Node grid generator (Model ▸ Geometry): nx × ny nodes with spacings.
Tables: type or paste coordinates into the Nodes grid (paste a block from Excel; rows past the end are added).

Members #

Member tool (M): click a start node and then the end nodes of a chain; Esc ends the chain. The next member's section, material and end releases are shown in the Properties panel.
Section (Model ▸ Properties): every AISC v16 shape (2,299 shapes, 14 families) with search and a family filter, or a parametric section (rectangle, round, pipe, HSS, I, channel, angle, tee).
Material: steel, concrete, wood and other grades from the library, or custom values (E, G, Fy, Fu, density).
End releases: presets (pinned at i, at j, truss) or single degrees of freedom in Properties. Releases are 12 flags: ux, uy, uz, rx, ry, rz at end i, then at end j.
Roll angle: rotates the section about its axis; with 0° a beam's strong axis (local z) is horizontal and its local y points up; a column's local z is global X. View ▸ Local axes shows x (red, i → j), y (green) and z (blue).
Split into equal parts, merge coincident nodes, move, copy, mirror, array, rotate the selection.

Plates #

Plate tool (P): click 3 or 4 nodes (Enter finishes a triangle). Thickness and material in Properties. The mesh tool and the free mesher (Analyze / Advanced) make plate regions with openings.

Supports and springs #

Fixed, pinned and roller presets (Model ▸ Supports) apply to the selected nodes or start the Support tool. Custom DOF / spring sets each of the six restraints or a spring stiffness per DOF (kip/in, kip·in/rad).

Grid lines and stories #

Model ▸ Grid lines & stories defines plan grid lines (labels, X or Y, position) and story levels (name, elevation). Story levels drive the drift checks, the diaphragms and the ELF / wind story loads.

Groups and selection #

Click selects; Shift adds, Ctrl toggles, Ctrl+Shift removes. A left drag draws a box: left to right selects what is fully inside, right to left what it crosses. Groups & select by… saves named selections and selects by section, material, orientation or level. Design groups (Design ▸ Setup) are separate: they carry design parameters.

Advanced model features #

Rigid links (master and slaves), rigid diaphragms per story, rigid end offsets, symmetry conditions, Winkler soil springs, prestress tendons with losses, nodal masses, settlements and thermal loads (Model ▸ Advanced and the Advanced tab).

Import and export #

New model ▸ Import reads .ilxs, DXF, IFC, STEP, IGES, ETABS .e2k and mesh files (gmsh .msh, Abaqus .inp, UNV). Imported members get a default material and section: assign the real ones next. Home ▸ Export downloads .ilxs, DXF, IFC, CSV and a PNG of the view.