V.03.7Second-Order Closed-Form Solutions

Problem

Compare the P-Delta solution with exact second-order answers.

Reference

• Exact second-order solution of a cantilever with tip axial and lateral load (beam-column theory).
• Leaning column: the lateral stiffness of a frame drops by P/h for every leaning column of height h carrying P.

Model

• Cantilever split into elements, axial compression P and lateral load H at the tip
• Cantilever column tied to a pinned leaning column carrying P

Comparison

• The same tests check that a structure loaded past its buckling load is reported as buckled rather than solved.

Reproduce

This is a closed-form or table check with no project file; it runs in the solver test pdelta_closed_form.rs.

Automated test: pdelta_closed_form.rs, run on every change.