Strength and strengthening of materials for rope applications

A rope can be described as a tension member that combines tensile strength with flexibility. The principal acceptance criterion of a rope is its tensile breaking force, of which the rope making material is the most important influencing factor. At present, steel wires and polymeric fibres (both natural and synthetic) and sometimes combinations of them are used to manufacture wire ropes, fibre ropes and hybrid ropes. This paper begins with a historical review of the development of ropes and the alternation of the dominant role between fibre ropes and steel wire ropes in conjunction with the evolution and improvement of tensile strength. Then the theoretical strength of materials is discussed and reasons why existing rope making materials’ strength is well below the theoretical strength are examined. As steel wires are much better understood the paper only reviews and discusses the characteristics of deformation and micro mechanisms of failures of high performance fibres including UHMWPE fibres and aramid fibres. The last section of the paper is devoted to the prospects of future development by introducing the ultimate rope or rope-like structure and newly emerging materials including carbon nano tubes.

Author(s): Wang, P.