Influence of the Test Frequency on the Fatigue Behaviour of Stay Cables

This paper describes the influence of the testing frequency on the fatigue behavior of stay cables. Different stay cable systems were tested with frequencies less than 8 Hz, according to the existing testing guidelines (fib recommendations, bulletin 30, 2005) [1]. These tests were carried out with servo-hydraulic testing machines. The same stay cable systems were then tested in the high frequency testing facility with frequencies up to 26 Hz. Tests with higher upper loads and higher load cycles where also carried out. First results show evidence that there is no detectable influence of the testing frequency (max. 26 Hz) or the number of load cycles. On the other hand higher upper loads during the fatigue tests resulted in a lower tensile strength of the specimen during the subsequent static tensile tests.