Flexibly connected beam element stiffness equations of guyed towers

With the growth of the telecommunications industry, the demand for taller, more reliable antenna towers and antenna-supporting stmctures has increased in the past decade. Many of these taller guyed towers are more flexible and aerodynamically sensitive to the natural wind environment. There have been a number of reported failures of guyed towers because of design, construction or maintenance problems and these failures were traced to the neglect of dynamic effects. Consequently, it is important to obtain more information on the dynamic response of tall guyed towers subjected to timevarying wind forces in the natural environment .A guyed tower is an example of a structure with nonlinear behavior under normal service loads. The nonlinear stmctural behavior of a guyed tower is influenced by a number of parameters, a fact that complicates the analysis of this stmctural system significantly. The guy cables are the primary source of nonlinearity in guyed towers.Their nonlinear behavior is due to the change in their stif&iess corresponding to any change in their tensions. This results in a nonlinear force deformation relationship for the entire stmcture. The work begins by defining the main assumptions required to derive the cable element nonlinear partial differential equations of motion in space. The chapter introduces the Newmark-yff method for performing direct time integration of the nonlinear system equations and the finite difference method to model the nonlinear equations of motion of the cable element in a discrete form for numerical solution.

کلیدواژه ها:

guyed towers ، Flexibly connected ، beam element ، stiffness