Fatigue and fracture of threaded connections

Published on Jan 1, 1994
· DOI :10.1016/B978-0-444-81645-0.50017-2
J. Toribio1
Estimated H-index: 1
This paper presents stress intensity factor (SIF or K) solutions for a semi-elliptical surface crack in a bolt subjected to tension, bending, residual stresses and nut loading. Solutions were numerically computed by a 3D finite element method (FEM) with quarter-point singular isoparametric elements along the crack line. The stress intensity factor was calculated through the stiffness derivative method, by using a virtual crack extension technique to compute the energy release rate. SIF solutions for different loading conditions are given along the crack front related to the ratio of crack depth/bolt minor diameter and to the crack aspect ratio. A second order polynomial interpolation was carried out on the results, in order to provide analytical expressions useful for fatigue life predictions.
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