Recent improvements in cycle counting methods have increased the value of the block load programme as a method of simulating the fatigue damage caused by random service loading.
It has already been observed that some of the lower load levels in certain block programmes make insignificant contributions to the total fatigue damage, and that the elimination of such levels can provide a very valuable method of accelerating tests.
This paper presents further evidence in support of this observation, and proposes an analytical method by which the damage significance of each block may be predicted, thus enabling a rapid selection of those levels which may be safely omitted.
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