StructureTool2D © Read Me

StructureTool2D © is a structural analysis and learning application for beams, frames, and trusses. The program uses Excel-based input templates to define structural geometry, support conditions, member properties, and loading, then performs analysis and generates plots, tables, and output files to help users study structural response.

The application currently supports three main instructional workflows.

A-B: Structure Data & Stiffness Method

This workflow is used for direct analysis of beam, frame, and truss structures using the stiffness method. The program reads the structure data, discretizes members where needed, forms element and global stiffness relationships, and computes nodal displacements, support reactions, and member actions. It also provides graphical output for structure geometry, deflected shape, and internal force diagrams.

C-D: Unit Load Method / Force Method

This workflow expands the educational scope of the tool by supporting concepts related to the Unit Load Method (ULM) and the Force Method (FM). These features are intended to help users study structural behavior, compatibility, redundants, and displacement evaluation in a more instructional and visual format.

E: Slope Deflection Method (Beam/Frame)

Section E adds a dedicated Slope Deflection Method (SDM) workflow for beam and frame workbooks only. It is intended for continuous beams and rectangular frames, and it summarizes the problem classification, active unknowns, sidesway status, solved SDM unknown values, and the maximum absolute end moment.

The current Section E implementation is limited to horizontal beams and vertical columns. It supports continuous beams, rectangular non-sway frames, and rectangular frames with at most one independent sidesway degree of freedom. Members are treated as inextensible in this workflow.

Section E reads the same workbook selected in the A-B tab, provides a beam/frame geometry preview, runs the SDM solution, and can produce a method output package with solved end moments, member shear or force recovery tables, support reactions, and related equation previews. A report generation option is also included in the workflow.

Section E Scope and Current Limits

Section E is available only for beam/frame models. Truss workbooks are rejected.
Only horizontal beam and vertical column layouts are currently supported.
Member hinge flags are not supported in the present SDM implementation.
Frames with more than one independent sidesway degree of freedom are outside the current scope.
If the workbook combines trapezoidal member loads with SDM cases that require translation or sidesway handling, that case is outside the current Section E scope.
Section E is aimed at worked, instructional output, not only final numerical answers.

Typical Use

Download the structure data template.
Enter the structural model, supports, properties, and loading in the Excel file.
Save the completed file.
Upload the file through the web interface.
Use A-B for stiffness-method analysis and plotting.
Use C-D for ULM or Force Method study tasks.
Use E for Slope Deflection Method study of eligible beam and frame models.
Review the generated summaries, plots, and downloadable output files.

Included Plots and Outputs

undeformed geometry
deformed shape
applied member and nodal loads
support reactions
axial force, shear force, and bending moment diagrams
truss member axial-force results
ULM and FM instructional outputs
Section E SDM outputs, including classification, unknown summaries, equation previews, end moments, force recovery tables, and support reactions

Important Notes

Use the truss option only for valid truss input files.
For beam and frame problems, select a suitable discretization level when distributed or varying loads are present in the stiffness workflow.
Section E uses its own SDM scope rules and does not accept every beam/frame configuration that may be analyzable in the stiffness workflow.
Review all plotted results carefully, especially when using display options for scaling, deformation, and force diagrams.
Always confirm that the entered units, loading, support conditions, and member properties are consistent.

Educational Purpose: StructureTool2D © is intended primarily as an educational and instructional tool. It is designed to help students and users better understand modeling assumptions, load idealization, stiffness-based analysis, unit-load and force-method concepts, slope-deflection relationships, internal force development, structural response, and related engineering concepts.

User Responsibility and Caution

Users are expected to exercise appropriate caution, sound engineering judgment, and independent verification when preparing input data, interpreting analysis results, and drawing conclusions from the software output. All results should be checked for reasonableness and consistency with expected structural behavior.

Disclaimer

This software is provided for educational use, demonstration, and preliminary study purposes only. Although care may be taken in its development, no warranty or guarantee is given that the application is free from errors, omissions, numerical limitations, modeling assumptions, coding defects, or user-input effects. The author and distributors accept no liability for any loss, damage, claim, or consequence arising from the use of the software or from reliance on its results.

Accordingly, StructureTool2D © must not be used as the sole basis for final engineering design, professional certification, construction decisions, or safety-critical assessment without independent checking and verification by a qualified engineer.