Comparison of the effect of changing soil class on earthquake force in a reinforced concrete structure with linear analysis methods

The fact that the structures are on the safe side and do not pose a danger can be explained by the fact that the structure meets all the forces on it. These loads affecting the structure can be grouped under headings such as live, dead, wind, earthquake, water, ground load. Except for the earth quake load, all other loads have a single value, while the earthquake load may differ according to the analysis method applied in the solution. In addition, the earthquake load is affected by the coordinates in which the building will be constructed, the height of the building, the local ground class, the building importance factor, response reduction factors. The purpose of the evaluation and design of the buildings is given under two headings in TBEC 2018. These are linear analysis methods and nonlinear analysis methods.While linear analysis methods are divided into two as Equivalent Earthquake Load Method and Modal Analysis Methods, nonlinear analysis methods are divided into two titles as time history and Pushover Methods. In this study, it is aimed to examine the effect of building height and changing ground classes on the base shear force. For this purpose, two separate 5-storey and 10-storey buildings with the same structural systems were modeled. Equivalent earthquake load analysis and mod combination analysis were used to calculate the base shear force acting on the base of the modeled structures. Structural Analyzes were made with the SAP2000 analysis program, and as a result of the analysis, the change in the base shear force acting on the structure in ZA, ZB, ZC, ZD and ZE ground classes was reported. As a result of the analyzes, it was observed that the equivalent base shear forces in the ZA, ZB, ZC ground classes in the 5-storey building were 10%-20% larger than the mode combination forces, while this value reached approximately 20%-25% in the ZD and ZE ground classes. On the other hand, in a 10- storey building, equivalent base shear forces yielded 25% greater results than the mode combination forces in each ground class.