Stability Lab looks for mechanisms: any way the structure can move without a member stretching or bending. If there are none, it pushes the structure along X and Y to measure lateral sway, and applies a downward Z push to explore vertical load transfer.
Your structure
Key
Rigid end: no hinge drawn
Pinned end (hinge)
Pinned support
Fixed support
Cable (tension only)
Slack cable (doing nothing)
Line width: thin, regular, large
Design code
Copy this code to save or hand in your design. Paste a code here and press Load to open one.
About: Stability Lab
What this tool does
Stability Lab is an interactive tool for learning structural stability and load paths.
Build and explore: create 3D frames, braced structures, walls, floors and bridges with different joints, supports and member sizes.
Check stability: identify independent mechanisms and watch how an unstable structure can move.
Compare stiffness: apply standard X, Y and Z pushes, view enlarged deformations and compare lateral sway. Tension-only cables are checked for load reversal.
Trace load paths: follow forces from all applied loads or one loaded joint to the foundations; inspect member forces, bending, panel forces and support reactions.
Predict member forces: predict tension, compression and bending for selected members, then check one or more answers for immediate feedback.
Take on challenges: improve a design and compare its cost-based efficiency score once it is stable and sufficiently stiff.
Educational purpose
Developed for CENV2035 City Infrastructure Design Project at the University of Southampton, to help students connect structural systems, connection types, bracing and diaphragms with stability.
Author and contact
Developed by Dr Ahmed Elkady, Associate Professor of Structural Engineering, University of Southampton. Email: a.elkady@soton.ac.uk · Homepage
The graphics and structural analysis engines were created by Claude AI (Anthropic).
Related publication
Elkady, A. (2026). “Stability Lab: A browser-based interactive application for the gamified teaching of structural stability and load paths” Computer Applications in Engineering Education (under review).
How to cite
Elkady, A. (2026). Stability Lab: an interactive 3D tool for teaching structural stability and bracing (Version 3.0) [Web application]. University of Southampton.
Licence
Licensed under Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0). You may use, share and adapt it for non-commercial teaching and learning, provided you credit the author, link to the licence, indicate changes, and share adaptations under the same licence. Commercial use requires written permission from the author. The University of Southampton name and logo are trademarks of the University and are not covered by this licence.
Disclaimer
Stability Lab checks stability and relative stiffness only. It does not check member strength, buckling or code compliance, and must not be used for design. Provided "as is", without warranty of any kind.