ultimate load

ultimate load

[′əl·tə·mət ‚lōd] (mechanics) breaking load

breaking load, failure load, fracture load, ultimate load

The load which, if placed upon a structure or test piece, is just great enough to break it.

ultimate load

In stress analysis, the minimum load that in its last increment causes a physical breakdown in an aircraft or component during a strength test or a load that, according to computation, should cause such a breakdown. Normally, the ultimate load is higher than 1.5 to 1.7 times the normal load in flight.
From O to A the stress is proportional to the strain and A is the proportional limit. At B, elongation begins and the material becomes plastic. The yield point is thus at C, at which point the material begins to strain harden. Point D represents the maximum tensile stress or the ultimate strength. At E the fracture takes place. E is the ultimate load in this case.