Date of Award

Spring 3-1995

Document Type

Thesis - Open Access

Degree Name

Master of Aerospace Engineering


Graduate Studies

Committee Chair

Habib Eslami

Committee Member

Howard D. Curtis

Committee Member

Frank Radosta


The vibration responses of three unsymmetrically laminated beams, that are excited with a Gaussian random forcing function, are studied in this thesis. The beams are analyzed nonlinearly and compared to linear results, indicating some important corrections. The solution procedure begins with the derivation of the general equation of motion using Galerkin's method. Then, two approaches are taken in the solution. First, the equation of motion is attacked directly employing a real time Runge-Kutta numerical analysis. Second, the method of equivalent linearization is used. The thesis finds the results from the two approaches to be in a close agreement, although some discrepancies at high loads could be found. However, the most important achievement of the thesis is undoubtedly that the same response equation can be used for any type of laminate layup, and any of the three types of beams. One of many applications that the solution can be used for is the assessment of fatigue tolerances.