Chapter 8 – Welded Connections Subjected to Fatigue Loading

This chapter discusses the welded connections subjected to fatigue loading. The fatigue phenomenon is characterized by a progressive degradation of strength under time variant stresses. The fatigue life of a structure includes a crack initiation phase and a crack propagation phase. The fatigue life of welded connections depends upon the connection detail and applied cyclic loading spectrum. Several methods can be used to determine the fatigue resistance of welded connections. This chapter covers the classification model, which include the classification method, punching shear method, failure criterion method, static strength method, hot spot stress method and fracture mechanics method. The chapter covers the fatigue design of hollow sections and simple connections. Finally, the classification method is based on structural details for different types of connections, which are classified into various detail categories. Each detail category corresponds to a nominal stress range under which a connection fails, with a given probability, after 2 million cycles.