2DFrameCalc

Build and analyse a frame

1. Enter nodes by coordinates or generate repeated layouts. Use node-number and coordinate increments, block copies, and spreadsheet-range paste to build regular frames quickly.
2. Create member chains between the nodes. Assign sections, releases and optional tension-only or compression-only behaviour.
3. Define supports, including springs, inclined restraints and one-way reaction limits. Set section areas, inertias, material stiffness and density for self-weight.
4. Add nodal and member loads in named cases. Define combinations using expressions such as 1.35*DL + 1.5*LL, then run the analysis.
5. Review displacements, member forces, reactions and envelopes. Complete the report title block and select the diagrams and tables for the A4 calculation PDF.

Analysis and reporting features

• A 2D elastic frame model with member end actions, load cases and combinations, automatic self-weight, and envelope actions for design review.
• Generated node and member patterns, chain shorthand, block copying, spreadsheet-style editing, and selectable local and global result views.
• Spring supports, one-way support actions, end releases and axial-only ties or struts allow common idealised boundary and connection behaviours.
• The report tools arrange project details, diagrams, result tables and notes on the calculation sheet, which can be exported as a PDF.

Engineering checks

Before issuing a calculation, confirm geometry, member orientation, section units, restraint directions, load signs and combination factors. Use equilibrium and the deformed shape as first checks on the solution.

The solver reports structural actions and movement; it does not replace code-based member design, connection design or independent checking. Review one-way elements carefully because their active state can change the solution.

Model Information

Use this tab for the five PDF title-block fields, project notes and numerical diagnostics from the latest analysis. The top filename/title display is handled by the current file name, not a separate Title field.

Title-block fields

Element

Identifies the element, member or location.

Project No.

Records the job reference.

Page No.

Sets the starting page number for the PDF pack.

Designed by

Shows the designer initials or name.

Date

Adds the report date for this model.

Node Coordinates

Block generation: for a normal numeric node row, fill No. of Inc, Node Inc, X-inc and Y-inc to generate a series automatically. If End or Inc is Y, X-inc and Y-inc are treated as end coordinates and No. of Inc becomes the number of intermediate nodes. To remove a generated sequence, use the same Node, No. of Inc and Node Inc values and enter Delete in End or Inc; for example 1, 1, 1, Delete removes nodes 1 and 2. For a copied block, enter B1 to copy the nodes generated by the numeric row that starts at node 1, or B1-5 to copy every node generated by input rows 1 to 5. For block copies, Node Inc is added to each copied node number for each generated level. To move existing nodes generated by earlier input lines, enter M1-4 (or M1 for one line) in Node and the offsets in X-inc and Y-inc. A node appearing in several referenced lines moves once; deleted nodes are not restored. Spreadsheet range copy: click-drag across cells in the node coordinate grid to select a rectangular Excel-style range, or click a cell and press Ctrl+A to select the visible table. Ctrl+C copies tab-separated cells to Excel; Ctrl+V pastes tab-separated ranges back in.

Member Connectivity

1-2-3 creates members 1→2 and 2→3. Enter Rigid in Section for a weightless link with ten times the strongest axial and bending stiffness in Section Props; end releases still apply. Shorthand 1-2--6 expands automatically to 1-2-3-4-5-6 using the increment implied by the two node numbers immediately before --. Shorthand can appear within a longer chain and can be repeated: 1-67-2-3--6 expands to 1-67-2-3-4-5-6, and 1-2--4-8-10--14-20 expands to 1-2-3-4-8-10-12-14-20. To add a pin release, type P in Release start node and/or Release end node. To apply those releases only at the overall chain ends, type Y in Group. In Axial only, leave blank for a normal member, enter C for compression-only/strut action, or T for tension-only/tie action; the solver uses an active-set iteration and removes the member when its axial force is outside the permitted sign. Member generation: enter No. of extra and Node increment to copy the whole chain. Example: 1-2-3-4 with No. of extra = 4 and Node increment = 5 also creates 6-7-8-9, 11-12-13-14, 16-17-18-19 and 21-22-23-24. Member block copies: enter B1-12 in the Node chain column to copy every member generated by input lines 1 to 12. With No. of extra = 2 and Node increment = 17, line 1 chain 1-2--5 also creates 18-19--22 and 35-36--39.

Support Conditions

Columns: Node, Fixity (XYz), Angle (deg), X/Y springs (kN/m), z spring (kNm/rad), X/Y gap action and Generate (No. extra, Node inc.). Tick restrained degrees of freedom in Fixity. The Node column accepts compact support generation: 6,11,14 for an explicit list, 6-16 for an inclusive range, 6-16:5 for a range with stride, and mixed syntax such as 1-50:5,1,16. Duplicate node numbers in the same cell are ignored. Optional X and Y spring stiffnesses are in kN/m. Optional rotational spring stiffness is in kNm/rad. If Fixity contains one translational restraint only (X or Y) and Angle is entered, that row becomes an inclined translational support; the reaction acts along the entered angle measured anticlockwise from global +X. X action and Y action can be Both for normal linear support, + only for a support that can only give a positive global reaction, or − only for a support that can only give a negative global reaction. Example: a vertical bearing support that pushes upward only is Restrain Y ticked with Y action = + only.

Section Props

Assign section ref to members in the Members tab. Default = ref 1. Click the colour swatch beside Ref to choose from a simple grid of 20 colours for all members using that section. The × button restores the default member colour. Colours are saved with the model; changing them does not require another analysis. In every input table, Ctrl+I inserts a row above the active cell; Ctrl+Y or Ctrl+Minus deletes the active row. Ctrl+Z undoes a deletion and Ctrl+Shift+Z redoes it. Density is entered in kg/m³. SWT is generated automatically as a global Y UDL using density × area = kg/m, then × 9.80665 / 1000 = kN/m. If density is blank or zero, no self-weight is generated. Tagged older files with unit-weight values are converted when opened. Reference SWT in any combination, e.g. 1.35*SWT + 1.5*LL.

Loadings

Use the load tables for nodal loads, member UDLs, member point loads and load combinations. Case names update the top Result selectors after analysis. SWT is generated automatically from density and area and is available for combinations.

Stages

Mark optional members X in Members. In Stages, leave a case or combination blank for the full structure, or enter X to omit those members. Every case in a combination and the combination itself must have the same setting. Both ULS and SLS use that structure. Results identify excluded nodal and member loads and self-weight; check that the omissions are intended.

Displacements

Displacement results for the active case or combination selected in the top Result controls.

Member Forces

Member end forces for the active case or combination. Click a column heading to sort; click again to reverse the order. Click a member row to highlight it on the canvas; Shift-click selects a range in the displayed order. For C/T-only members, the summary panel reports whether each one-way member remained active or was released by the active-set solver.

Reactions

Support reactions for the active case or combination. One-way support contact status is shown where applicable.

Member Maximum Actions for Design

Envelope table of maximum member actions across all solved load cases, ULS combinations and SLS combinations. Check that these are the results intended for your design.

Report

Choose which diagrams and result tables to include in the export pack, then run Export PDF or take a snapshot.

Related tools

• 3DFrameCalc — Help
• BeamCalc — Help
• SteelCalc — Help