抄録
Fluctuating tensile load test was carried out on the stranded wire rope which was applied to the hanger rope for the long span suspension bridges. The S-N curve and the fatigue limit diagram were plotted. The tendency of increase of broken wire and the dynamic extension of the wire rope during the test were also measured to find out the progress of fatigue of the wire rope. The results obtained are summarized as follows
(1) The S-N curve by which the fatigue strength of the wire rope can be appreciated is obtained, and the fatigue limit is about 21kgf/mm2.
(2) Mean stress σm does not practically affect the fatigue strength.
(3) The wire breaking due to fatigue occurs more frequently on the low cycle side than the high one.
(4) The wire breaking due to fatigue occurs concentratively in the core rope than in the outer one.
(5) The wire breaking due to fatigue occurs shortly before the wire rope breaks.
(6) It is difficult to find out the extent of fatigue damage and the indication of breaking by means of the change of dynamic extension.
