To describe the centralized level of the stress root mean square (RMS) around a notch, this paper proposes a definition and calculation formula of the stress mean square concentration factor for notched specimens under dynamic excitation. A calculation formula for notch fatigue factor is presented based on the basic fatigue mechanism of structures and a consideration of the distribution characteristics of the stress root mean square in dangerous regions around a notch. Consequently the nominal stress approach for the life prediction of notched specimens under vibration loading is obtained. The results of three typical examples show that the method proposed in this paper can predict the vibration fatigue life of notched specimens well.
LI Deyong, YAO Weixing
. Nominal Stress Approach for Life Prediction of Notched Specimens Under Vibration Loading[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2011
, 32(11)
: 2036
-2041
.
DOI: CNKI:11-1929/V.20110419.1703.007
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