ENGINEERING FEASIBILITY OF INTERNAL FRICTION DAMPING AS A NONDESTRUCTIVE EVALUATION TECHNIQUE FOR SYNTHETIC ROPE

"This report discusses the technical feasibility of applying an internal friction damping, nondestructive evaluation technique for synthetic ropes. Applications for synthetic ropes include mooring lines, towing hawsers and lines for single point moorings (SPM) in deep water ports (DWP). The theory of internal friction damping is presented as it has been historically applied to metallic materials. The report then discusses the methodology for application of the internal friction damping technique to synthetic rope material and construction. The experimental apparatus and specific laboratory technique as applied to six inch and eight inch circumference rope is next discussed in detail. The report then discusses the experimental results and relates the test results to feasibility of employing the test technique as a guideline device for rope deterioration/performance. The report also relates this discussion to characteristics of the ropes tested under both wet and dry conditions. The experimental results section concludes with a comparison of the effect of the internal friction damping for various synthetic rope failure mechanisms. The report ends with specific conclusions and recommendations for further investigation into large synthetic rope testing and inspection for the ultimate feasibility determination for the potential development of DWP hawser performance hardware."