Structural Engineering and Mechanics

Volume 70, Number 1, 2019, pages 33-41

DOI: 10.12989/sem.2019.70.1.033

Influence of geometry and safety factor on fatigue damage predictions of a cantilever beam

Matija Pecnik, Marko Nagode and Domen Seruga

Abstract

The influence of two parameters on fatigue damage predictions of a variably loaded cantilever beam has been examined. The first parameter is the geometry of the cantilever beam and the weld connecting it to a rear panel. Variables of the geometry examined here include the cantilever length, the weld width on the critical cross-section and the angle of the critical cross-section. The second parameter is the safety factor, as set out by the Eurocode 3 standard. An analytical approach has been used to calculate the stresses at the critical cross-section and standard rainflow counting has been used for the extraction of the load cycles from the load history. The results here suggest that a change in the width and angle of the critical cross-section has a non-linear impact on the fatigue damage. The results also show that the angle of the critical cross-section has the biggest influence on the fatigue damage and can cause the weld to withstand fatigue better. The second parameter, the safety factor, is shown to have a significant effect on the fatigue damage calculation, whereby a slight increase in the endurance safety factor can cause the calculated fatigue damage to increase considerably.

Key Words

fatigue damage; welded joint; rainflow; cantilever beam; fatigue

Address

Matija Pecnik, Marko Nagode and Domen Seruga: University of Ljubljana, Faculty of Mechanical Engineering, Askereeva 6, SI-1000 Ljubljana, Slovenia