Structural Engineering & Statics
where the load goes
Generator

The unit-load generator

Rendered here at the parameters it defaults to, with every essay that calls it — which is the same list as the blast radius of changing it.
The deflection at x = 3, by virtual workThree diagrams: the moment from the real load, the moment from a unit load placed where the answer is wanted, and their product. The area under the third, divided by EI, is the deflection — 197.50 here. No standard case was consulted, so the method works for any load pattern at all.real Mpeak 32.0a unit load, here and nowhere elseunit mM × marea ÷ EI = 197.50the unit load is the only place the question 'deflection where?' is asked

1 essay calls unit-load. The drawing above is what it returns with no arguments at all; every call below passes it something, because a placement that passes nothing draws whichever member of the family the generator happens to default to rather than the one its essay argues about.

Where it is called

Changing this generator changes every one of these figures.

real Mpeak 32.0a unit load, here and nowhere elseunit mM × marea ÷ EI = 213.33the unit load is the only place the question 'deflection where?' is asked Deflection

One deflection, without solving everything

To find how far one point of a structure moves, put an imaginary force of one unit there, multiply two moment diagrams together, and integrate. The answer arrives without ever solving for the deflected shape.

The whole library