Fatigue Analysis of Numerical Bolted Connections

This paper was produced for the 2019 NAFEMS World Congress in Quebec Canada

Resource Abstract

The work presented in this paper deals with the numerical fatigue damage assessment of bolted joints and their fatigue life through an iterative process. For that purpose, one tee stub in which bolts are submitted to pretension force is numerically studied by the use of Finite Element Model on Salome-Meca software. Then a 3D screw model involving the first thread of the screw shank engaged in the nut and the fillet radius between the head and the screw shank is simulated and finely meshed in the stress concentration zones. The preload influence is particularly underlined as it strongly improves the fatigue resistance of the bolt whatever the geometrical parameters are. A parametric study is also carried out to analyse the influence of the bolt location m and the column flange thickness t_f onto the bolt fatigue resistance. A multiaxial fatigue post-treatment tool has thus been implemented on Matlab software for fatigue damage and fatigue life assessment purpose. Two multiaxial fatigue approaches contribute to this tool and may be used to predict the bolt fatigue behaviour. The so-called critical plane approach (Dang Van criterion) and the integral approach (Zenner criterion) are compared for that analysis.