DYNAMIC STIFFNESS MATRIX OF A GENERAL CABLE ELEMENT

A computational scheme for determining the dynamic stiffness coefficie nts of a linear, inclined, translating and viscously/hysteretically da mped cable element is outlined. Also taken into account is the couplin g between inplane transverse and longitudinal forms of cable vibration . The scheme is based on conversion of the governing set of quasistati c boundary value problems into a larger equivalent set of initial valu e problems, which are subsequently numerically integrated in a spatial domain using marching algorithms. Numerical results which bring out t he nature of the dynamic stiffness coefficients are presented. A speci fic example of random vibration analysis of a long span cable subjecte d to earthquake support motions modeled as vector gaussian random proc esses is also discussed. The approach presented is versatile and capab le of handling many complicating effects in cable dynamics in a unifie d manner.