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.
","abstract_html":"<p>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.</p>","abstract_has_math":false,"creators":["Gudmundsson, Snorri"],"institution":null,"degree_name":"Master of Aerospace Engineering","degree_level":"Thesis - Open Access","degree_discipline":"Graduate Studies","degree_department":null,"school":null,"contributors":["Habib Eslami","Howard D. Curtis","Frank Radosta"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":1995,"date_issued":"1995-03-01T08:00:00Z","date_published":"1995-03-01T08:00:00Z","updated_at":"2026-07-27T19:25:16Z","subjects":["nonlinear analysis","composite beams","random excitations","Aerospace Engineering"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://commons.erau.edu/db-theses/280","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Habib Eslami","Howard D. Curtis","Frank Radosta"]},{"key":"dc:creator","label":"Author","values":["Gudmundsson, Snorri"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"thesis:degree_discipline","label":"Discipline","values":["Graduate Studies"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis - Open Access"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Aerospace Engineering"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["nonlinear analysis","composite beams","random excitations","Aerospace Engineering"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://commons.erau.edu/db-theses/280"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["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.
"]},{"key":"dc:title","label":"Title","values":["Nonlinear Analysis of Composite Beams under Random Excitations"]}]}],"canonical_facts":{"dc:contributor":["Habib Eslami","Howard D. Curtis","Frank Radosta"],"dc:creator":["Gudmundsson, Snorri"],"dc:description.abstract":["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.
"],"dc:identifier":["https://commons.erau.edu/db-theses/280"],"dc:subject":["nonlinear analysis","composite beams","random excitations","Aerospace Engineering"],"dc:title":["Nonlinear Analysis of Composite Beams under Random Excitations"],"thesis:degree_discipline":["Graduate Studies"],"thesis:degree_level":["Thesis - Open Access"],"thesis:degree_name":["Master of Aerospace Engineering"]},"updated_at":"2026-07-27T19:25:16Z"}