Shear — where it appears
Named by 2 essays across 2 fields — each of them below, with the objects they name alongside it.
The beam that becomes a truss
Once a web has cracked in shear there is no shear stress field in it any more. There are concrete struts, two chords and whatever crosses the cracks, and the angle of those cracks is not a property of the material — it is something the designer chooses, and every quantity in the beam moves when it changes.
Both at once, and neither matters until it does
A section carrying shear has less moment capacity, and the reduction is the web's share of the plastic modulus times one minus the root of one minus the shear ratio squared. On a rolled beam that share is a quarter, so half the shear capacity costs three and a half per cent — and then the last tenth costs more than the first eight.
Named alongside it
The objects these essays reach for when they reach for this one.
Bending stressConcrete strutContinuous beamCracked sectionEquilibriumFlangeFree bodyInteractionLever armPlastic hingePlastic modulusPrincipal stress