BIM Structural Frame + ASCE 7 Load Combinations

What it is

A 2D structural frame/truss analysis with the full ASCE 7-22 load-combination sweep. Define nodes, members (E/A/I), supports, and nodal loads TAGGED by load case (Dead, Live, Roof-Live, Snow, Wind, Seismic, Rain); it assembles the global stiffness matrix, solves K u = F by Gaussian elimination with partial pivoting for every LRFD (section 2.3) and ASD (section 2.4) combination, and reports the governing displacement plus the per-member axial/shear/moment ENVELOPE with the combination that governs each, and an Euler buckling demand/capacity for compression members. The solver is anchored to the closed forms (cantilever P L^3/3EI, simply-supported P L^3/48EI, axial P L/EA) and its solution residual sets the trust verdict. Honest scope: 2D first-order linear-elastic analysis (no P-delta, inelasticity, connection flexibility, or out-of-plane), and the seismic combos use the nominal E you enter (the 1.2+0.2 SDS split / overstrength are not auto-applied). A design-aid bridge to ETABS/SAP2000/RISA, not a stamped analysis. Deterministic, in-browser, no API/key/network/AI.

Honest scope

Authorities cited

• ASCE/SEI 7-22, Minimum Design Loads and Associated Criteria, section 2.3 (Strength Design / LRFD combinations 2.3.1) and section 2.4 (Allowable Stress Design combinations 2.4.1) - the load factors used verbatim.
• R. C. Hibbeler, Structural Analysis, and W. McGuire, Matrix Structural Analysis, 2nd ed. - the direct-stiffness method, the Euler-Bernoulli frame element 6x6 stiffness, and the rotation transformation used here.
• AISC Steel Construction Manual / Euler buckling Pcr = pi^2 E I /(K L)^2 - the elastic buckling screen for compression members (effective length factor K is a confirmed input).