Concept
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3 essays name this object, across 2 fields. What follows is each of them, and the objects they name alongside it.
Everything adds to nothing, and that is the whole of statics
A structure that stays put obeys two statements — the forces on it sum to zero, and so do the moments. Every number in the subject comes out of those two sentences.
The free body is a choice, and choosing it well is the whole skill
Cutting a structure open is not a step in the method. It is the method — and where the cut is made decides whether the answer takes one line or twenty.
Where to put the supports, which is not at the ends
Moving the supports of a uniformly loaded beam inward by about a fifth of its length halves the worst bending moment. The load has not changed and nor has the beam.
Named alongside it
The objects these essays reach for when they reach for this one.
Free body diagramBoundaryContinuityEquilibriumForce equilibriumHogging and saggingIdealisationInternal forcesMethod of sectionsMoment envelopeMoment equilibriumNewton's third law