Zekaria, Adil(PhD)Getachew, Daniel2018-06-132023-11-112018-06-132023-11-112011-04http://etd.aau.edu.et/handle/12345678/798This thesis is conducted to evaluate seismic vulnerability and investigate nonlinear behaviors of existing reinforced concrete buildings constructed in Addis Ababa. The paper examines four structures using nonlinear dynamic analysis software (IDARC 2D ver. 7.0). Each of these structures will be analyzed for three peak ground accelerations of 0.05g, 0.07g and 0.10g. The finding of this research is that two of the four buildings will collapse immediately when an earthquake (of intensity 0.05g, 0.07g and 0.10g) occurs. It is also found that the other two buildings resist the seismic loads that will occur during an earthquake and the story force deformation time history responses of these two buildings show stiffness degradation, strength decay and pinching behaviors of reinforced concrete structures. It was concluded that some of the buildings deform beyond the limit of linearly elastic range and due to the high damage of the main structural elements, the buildings will no longer give service or a total collapse will occur after earthquake. It is recommended to evaluate seismic vulnerability of the existing buildings in Addis Ababa based on nonlinear analysis procedures. Keywords: Seismic Vulnerability; Nonlinear Dynamic Analysis; Stiffness Degradation; Strength Decay; PinchingenSeismic Vulnerability; Nonlinear Dynamic Analysis; Stiffness Degradation; Strength Decay; PinchingThesis