抄録
Recently in Japan, IWRC (Independent Wire Rope Core) wire ropes are widely used on crane. Comparing with traditional fiber core rope, IWRC is known to be prone to undetectable internal damage. Although a number of fatigue tests on IWRC have been done with the aim of life prediction and investigation of fracture characteristic, the mechanism of fracture has not been proved for the reason that it is difficult to observe where and when the internal damage occurs. In this study, to visualize the stress state of inner wires, we performed FEM analysis on two kinds of widespread IWRC rope, 6×WS(31) and 6×Fi(29), bent and dragged along sheave. The method of zooming analysis was introduced to this analysis for dealing with computational difficulty caused by the geometrical complexity of IWRC. The result of this analysis shows qualitative agreement with the result of S-type bending fatigue test that inner wires of Fi(29) rope has stronger tendency than those of WS(31) to break prior to visible damage.
