The residue contains the turning points that do not satisfy the Rainflow algorithm. The residue is generally a zigzag curve with ascending and descending amplitudes. In particular, if univariate collectives such as peak values are to be extracted from the Rainflow matrix, the residue should be included in the matrix.

FlexPro offers several algorithms to handle the residues [1, 2].

In service life calculations, the residue can usually be ignored if a large number of load cycles (closed hysteresis) occur. Otherwise, the residue should be included because the half cycles remaining as residue can contribute to fatigue damage [3].

References

[1] de Jonge, J.B. (1980). Counting Methods for the Analysis of Load Time Histories. NLR Memorandum SB-80-106 U

[2] ASTM E1049-85(2017). Standard Practices for Cycle Counting in Fatigue Analysis. STM International, West Conshohocken, PA, 2017

[3] FVA (German Research Association for Drive Technology) 131 IV (2010 edition) ZÄHLVERFAHREN ZUR BILDUNG VON KOLLEKTIVEN UND MATRIZEN AUS ZEITFUNKTIONEN (COUNTING METHODS FOR THE FORMATION OF COLLECTIVES AND MATRICES FROM TIME FUNCTIONS). FVA Guideline. FVA Forschungsvereinigung Antriebstechnik e.V (Research Association for Drive Technology)