Fatigue failure analysis of stay cables with initial defects: Ewijk bridge case study

Revision of EN 1993‐1‐11 – fatigue design rules for tension components

“…wire to the break of the rope, or whether the inner or outer wires break first. It is clear, however, that failure of full locked coil ropes usually occurs in the Z-shaped wire, because of its greater stiffness and thus higher secondary bending stresses and the greater probability of surface defects, see [20,21] or [23].…”

“…Surface defects act as initiators of fatigue cracking. Although they are often caused by the drawing process (see [18] or [20]), the drawing process itself also leads to a decrease in the size of the defects [21].…”

Fatigue design of tension components: Revision and further development of EN 1993‐1‐11

“…It is clear, however, that failure of full locked coil ropes usually occurs in the Z-shaped wire, because of larger stiffness and thus larger secondary bending stresses and the larger probability of surface defects; see (10), (11) or (12). Cold-drawing introduces high tensile residual stress at the surface (and compression residual stress at the centreline).…”

Probabilistic prediction of fatigue damage based on linear fracture mechanics

“….    (28) and (29) If re-distribution of stress from a point that is weakened by the crack is not taken into account, the crack propagation crack is usually rather high in the practical range of detectable values. If a fatigue crack is found during the inspection, it is necessary to monitor the safe growth of the crack or to take actions that will slow down or stop further propagation of the fatigue crack.…”

“…Considering the detail of connection of the flange plate, it was decided to choose the mean value of a 0 = 0.2 mm with lognormal distribution. The chosen mean value a 0 = 0.2 mm with log-normal probability distribution represents a significant asymmetry histogram with a larger variance for a0 > 0.2 mm according to [29]. The probabilistic calculation was performed using FCProbCalc software ("Fatigue Crack Probability Calculation") [17], which has been developed using the aforementioned techniques.…”