Forced vibration analysis of generally laminated composite beams using domain boundary element method

Ahmed, Zubair
Forced dynamic response of generally laminated composite beam is analyzed by boundary element method. Static fundamental solutions are used as weight functions in the weighted residual statements. The use of static fundamental solutions gives rise to a new formulation named as Domain Boundary Element Method. Displacement field of the generally laminated composite beam is written in accordance with first order shear deformation theory and equations of motion are derived using Hamilton’s principle. Developed formulation includes the Poisson’s effect as well as influence of rotary inertia and shear deformation. Bending, extensional and torsional response couplings, due to orthotropic nature of the problem, are included in the formulation. Domain integrals, in the integral formulation of the problem, are evaluated by discretizing the domain and using interpolation functions. Houbolt method is used for solving the resulting system of equations. Dynamic response, obtained via Houbolt method, is verified by comparison with analytical solution available for an homogeneous isotropic Timoshenko beam. Dynamic response of generally laminated composite beams is studied under the action of time based excitations such as concentrated step, harmonic, impulsive and uniformly distributed step loads. Influences of fiber angle in each lamina and stacking arrangement on temporal variation of deflections and longitudinal normal stress have been studied in parametric analyses. It has been demonstrated that the developed technique is an accurate and effective alternative for forced vibration analysis of generally laminated composites.


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Citation Formats
Z. Ahmed, “Forced vibration analysis of generally laminated composite beams using domain boundary element method,” M.S. - Master of Science, Middle East Technical University, 2018.