Structural Engineering & Statics
where the load goes
Concept

Series combination — where it appears

Two flexibilities acting one after the other along a load path, which add — so the softer governs and improving the stiffer buys almost nothing.

Named by 2 essays across 2 fields — each of them below, with the objects they name alongside it.

bending, as a solid column doesP_E = 1341 kNracking, which a solid column cannotS_v = 31500 kN1/P꜀ᵣ = 1/P_E + 1/S_v → 1287 kNthe smaller of the two governs, and here it is the bending

The column made of two columns

A solid column buckles when its bending stiffness runs out. A laced one has a second way to go — the lattice shears, the chords stay straight — and the two flexibilities add rather than the two stiffnesses. A battened column reaches 23% of its own Euler load and behaves as though its slenderness were twice what it is.

stability · built up column 4020080030002000000.20.40.60.81stiffness of each supportfraction of the deflection that is bendingrigid supportsare over here1%the beam drawn

The deflection that belongs to the support

A beam calculation answers a question about a beam sitting on things that do not move. Real ones sit on bearings, on other beams and on columns that shorten, and every one of those is a spring in series with the member — so a deflection is the sum of two things and only one of them is a property of the beam.

deflection · support flexibility

Named alongside it

The objects these essays reach for when they reach for this one.

Axial shorteningBattenBearingBucklingBuilt up columnChordDeflectionDifferential shorteningEffective slendernessElastic foundationEngesserEuler load

All concepts