The required minimum safety factor of bolted connection during fatigue loading nf represents a ratio of fatigue loading and the calculated stress of bolted connection, that is, n f ≤σ A / σ a or n f ≤τ A / τ a .
The recommended minimum value of safety factor at fatigue loading is indicated in the n f = <1.5...3> range and it depends on the fatigue loading pattern. In general, the reversed loading is less favorable than fluctuating loading when the fatigue loading of bolted connection is considered.
The following picture displays the effect of loading course to bolted connection safety. The range of recommended minimum values of safety factor, which depends on the value of cycle asymmetry factor r = σ n / σ h , is hatched.
