Local Bending Stresses In Cables

After a discussion of the various types of stiffness possible in a suspended cable responding to live loading, theory is presented for the steady-state response of a taut, flat cable in which allowance is made for flexural effects at its terminations. The steady-state response could be taken to refer to strumming effects due to, say, vortex shedding in an underwater application where, if the cable material is synthetic, it will be straight on account of the neutral buoyancy, or nearly such, of synthetic cables. Equally, it could refer to a bridge stay cable. In any event, the model presented for behaviour in the flexural boundary layers of cables provides a useful starting point for the development of fatigue theories for different types of response such as that induced by vortex shedding, or by parametric excitation (where motion at one termination may give rise to lateral motion in the cable). The appendix contains formulae for any type of cable whether solid, parallel lay or helical lay.