Habte, Bedilu (PhD)worku, Belay2018-07-242023-11-112018-07-242023-11-112016-04http://etd.aau.edu.et/handle/12345678/9921A reinforced concrete building symmetric in plan, having a height of 30 m, located in seismic zone II (ag=0.05g), has been analyzed and designed using Etabs software and according to EBCS provision. After the design is completed, the reinforced concrete frame is modeled and analyzed, employing geometric nonlinear Finite Element Modeling using Opensees software under two different boundary conditions: (I) fixed-base (no Soil-Structure Interaction), and (ii) considering Soil-Structure Interaction (SSI).The nonlinear behavior of a soil-foundation system alter the seismic response of a structure by providing additional flexibility to the system and dissipating hysteretic energy at the soil-foundation interface. However, the current design practice is still reluctant to consider the nonlinearity of the soil-foundation system, primarily due to lack of reliable modeling techniques. This study is motivated towards evaluating the effect of nonlinear soil-structure interaction (SSI) and frame structure without soil under seismic responses of low-rise reinforced conctremoment resisting frame (RCMRF) structures. In order to achieve SSI, a Winklerbasedapproach is adopted, where the soil beneath the foundation is assumed to be a system of closely-spaced, independent, nonlinear spring elements. Static pushover analysis is performed on a 10-story RCMRF building and the performance of the structure is evaluated through a variety of force and displacement demand parameters. It is observed that incorporation of nonlinear SSI leads to an increase in story displacement demand and a significant reduction in base moment, base shear and inter-story drift demands, indicating the importance of its consideration towards achieving an economic, yet safe seismic design.RCMRF was also modeled using sap 2000 with and without considering soil effect. The pattern of the outputs seems the same. But, the outputs of sap are relatively smaller in value than the opensees outputs.enstructural Engineering StreamThesis