Structural Engineering & Statics
where the load goes
Concept

Efficiency — where it appears

3 essays name this object, across 2 fields. What follows is each of them, and the objects they name alongside it.
0.511.52050100150200250300depth of the truss2501671251007150the same moment, resisted by a longer lever arm

Depth is the cheapest strength there is

Doubling the depth of a truss halves its chord forces without adding a gram of material to the chords. Nothing else in structural design is that cheap, and almost every structure has already spent it.

structures · span to depth s = 50g = 60net width 166.42 mm of 200the critical path crosses two holes, with s²/4g = 10.42 mm added back

The tear that goes diagonally, and the correction that has no derivation

Stagger the holes so that no straight line crosses more than one and the plate does not get its strength back. The tear runs at an angle instead, and the arithmetic that makes it come out right is a century-old piece of curve-fitting nobody has improved on.

connections · net section x̄ = 19.77connected legoutstanding legLc = 150net areaU = 0.87 of it worksU = 1 − x̄ / Lc = 0.87both halves are geometry — where the centroid sits, and how long the connection is

The angle that uses half of itself

Bolt an angle through one leg and the other leg is not fully working. The correction is one over a length — both halves of it are geometry, neither involves a material, and a two-bolt connection throws away a quarter of the section.

connections · shear lag

Named alongside it

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

ConnectionNet sectionBolt groupBucklingCentroidChord forceEccentricityEmpirical ruleLever armLoad pathSaint-Venant's principleSecond moment of area

All concepts