Date of Award
Master of Science (MS)
Mechanical & Aerospace Engineering
Earl A. Thornton
A numerical integration technique, a modified version of the Newmark method, is applied to transient motion problems of systems with mass, stiffness, and small nonlinear damping. The nonlinearity is cast as a pseudo-force to avoid repeated recalculation and decomposition of the effective stiffness matrix; thus, the solution technique is dubbed the "pseudo-force Newmark method." Comparisons with exact and perturbation solutions in single-degree-of-freedom problems and with a Gear-method numerical solution in a cantilevered Timoshenko beam finite element problem show the solution technique to be efficient, accurate, and, thus, feasible provided the nonlinear damping is small. As a preliminary step into the investigation of the active control of large space structures, a problem involving a free-free Timoshenko beam with nonlinear structural damping is solved. As expected, small damping is shown to be of little importance in the prediction of low-frequency vibrations while being of utmost importance in the prediction of high-frequency vibrations.
Roussos, Louis A..
"Finite Element Model of a Timoshenko Beam with Structural Damping"
(1980). Master of Science (MS), Thesis, Mechanical & Aerospace Engineering, Old Dominion University, DOI: 10.25777/772g-h942