Performance analysis according to 2018 regulations of structures analysis designed according to the 2007 Turkish earthquake regulations

Located in a seismic zone, our country's first earthquake regulation came into force in 1947, followed by new regulations in 1953, 1961, 1968, 1975, 1998, 2007, and 2018. According to the rules specified in Section 15 of the currently valid Turkish Building Earthquake Code, the seismic performance of existing structures can be evaluated using linear elastic or nonlinear analysis methods. This thesis study examines the seismic performance of three, six, and nine-story residential buildings located in the Buca district of İzmir, within the scope of the 2007 Regulation for Buildings Subject to Earthquakes (DBYBHY 2007) and the Turkish Building Earthquake Code 2018 (TBDY 2018). The seismic performance analysis of the structures was conducted using the nonlinear time history analysis method with the ETABS program. As a result of the analyses, it was determined that the performance level of the structures is "Limited Damage." In the study, it was observed that the shear wall structural system, compared to the traditional frame system, provided significant improvements in dynamic parameters such as lower base shear force, story shear force, story accelerati ons, and relative story displacements. This indicates that shear wall systems behave more effectively against earthquake effects. The structural models were created considering the DD-2 earthquake level and evaluated within the framework of the rules specified in Section 15 of TBDY 2018. The properties of concrete and steel materials were determined through destructive and non-destructive sample analyses. To model the nonlinear behavior in three dimensions, a lumped plasticity hinge model was used for columns and beams, while a distributed plasticity hinge model was defined for shear walls. Moment-curvature relationships were calculated using the XTRACT analysis program, and plastic rotation values were determined according to the Collapse Prevention (CP) and Controlled Damage (CD) performance limits. While applying the Nonlinear Time History Analysis (NTHA) method, earthquake records selected from the PEER earthquake database were used, and these records were scaled in detail to match the DD-2 earthquake level. In the analyses, a total of 22 earthquake records (in X and Y directions) from 11 different earthquakes were used, and these records were scaled using the SeismoMatch program. As a result of the analysis evaluations according to TBDY 2018, it was determined that the structure achieved the "Controlled Damage Performance Level" at the DD-2 earthquake level, and none of the reinforced concrete beam or column elements entered the collapse or extensive damage zones. However, significant damage was detected in some columns and shear walls. Specifically, while some columns in the first two stories of the building were in the significant damage zone, the majority of the shear walls remained in the limited damage zone. In summary, it was observed that shear wall-frame systems better withstand earthquake effects and significantly reduce the damage levels of structural elements. These findings demonstrate that the use of shear wall elements in the design of reinforced concrete multi-story buildings enhances structural performance and provides a safer and more ductile solution against earthquake effects. Keywords: Reinforced concrete structure, Seismic performance analysis of existing buildings, Nonlinear time history analysis, ETABS, XTRACT, Damage states, Plastic hinge, Shear wall structural system