fatigue analysis of bolts

[hhamza]

Am i interpreting Division 2, part 5 correctly that when using bolts in a cyclic operation, the maximum number of cycles is 1E6? I get this from table 3-F.9. The values in 3-F.8 (at the 13.5 KSI and 5.3 KSI limits) also confirm this.

Does this mean I can't have any bolted connections if my design requires more than 1 million cycles? That would seem strange.

 

[TGS4]

If you look at the shape of the curve, you will see that those values (13.5 ksi for maximum nominal stress ≤ 2.7S or 5.3 ksi for maximum nominal stress ≤ 3S) are essentially the endurance limits. Therefore, my opinion would be that the curve after the last provided data point is flat. Stress amplitudes below those values would have an infinite life.