CivilKit Buckling (CUFSM)
The finite strip method of CUFSM for thin-walled sections: the signature curve, its local, distortional and global minima, and the modes in 2D and 3D. The engine is cufsm-rs, an independent Rust port of CUFSM held to CUFSM's own results. For circular tubes, the finite tube method of Ádány and Schafer gives the buckling load under any mix of compression, bending, torsion and shear. These are elastic (bifurcation) results, the inputs to a design check, not the check itself.
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Signature curve and minima
Lipped channels, channels, Z sections, hats, plates and custom sections, with all five of CUFSM's end conditions.
cFSM classification
The global, distortional, local and other share of each mode, and the curves restricted to each.
Circular tubes
The finite tube method: load factors and buckled shapes under N, M, T and V, with free, pinned or clamped ends.
Runs in your browser
The engine is compiled to WebAssembly: nothing is sent to a server.
CivilKit Buckling (CUFSM) assists a qualified engineer; it does not replace one. Outputs must be checked against project requirements, applicable standards and site conditions before use in construction. Certification and sign-off remain with the registered engineer of record.