Slack-Elasto-Plastic Dynamics of Cable Systems

A numerical procedure for determining the nonlinear dynamic response of cable systems is presented in which cable segments may be included as elastic, plastic, or buckled (slack) elements. Individual cable elements in the network are assumed either elastic, plastic, or slack, depending on the time history of load and system response. Finite element analogs are used as the basis for numerical modeling for spatial behavior. The equations of motion were derived from the nonlinear Hamilton's principle and linearized incrementally to approximate the true behavior within each load or time increment. A curved element is adopted which maintains slope continuity between cable segments, and isoparametric displacement functions are adopted. The Newmark B method is used as the basis for the numerical integration for the temporal behavior.