Shifferaw, Taye (PhD)Tamirat, Kebede2020-11-202023-11-112020-11-202023-11-112020-05http://etd.aau.edu.et/handle/12345678/23404Paraboloid shells are translational shells formed from two parabolas placed at the right angle to each other and by the translation of one parabola over the other. Elliptical paraboloid is formed by two unequal parabolas with the same curvature sign. Thin concrete elliptic paraboloid shell with large spans are susceptible to buckling. Determining the critical buckling load, internal forces and free vibration is difficult because of the lack of experimental study on such shell type. The research is focused on the analysis of an elliptic paraboloid shell structure under its own weight. Geometrical and material linearity are considered in modeling and analysis of the structure in this study. The objective of the research is the parametric study on stability analysis of a thin shell structure under its own weight. In this study, the internal forces, moments, deformation, stability, and free vibration of elliptic parabolic shell analysis are performed by theoretical and finite element methods. Theoretical analysis is done by shallow shell theory and the finite element analysis is carried out by using DLUBAL RFEM 5.3.1. Theoretical formulas in this study are coded by the MATLAB program. The codes are used to determine internal force, moments, in-plane shear, displacement, critical load and time, angular frequency, natural frequency in free vibration are written in the appendix. The influences of the different parameters on the critical loads of the shells are thereby studied. The parameter considered is thickness, the radius of curvature, modulus of elasticity and side rise of the shell to determine the critical buckling load. Free vibration analysis of rectangular and square planned elliptic paraboloid shell structures was done. Finally, the internal forces, displacement, critical buckling load, and free vibration analysis result in the study presented graphically and discussed in detail. The result of the finite element analysis is then compared with the theoretical analysis results.en-USShell StructureThin Shell StructureStability AnalysisThesis