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Yayın Comparative study for earthquake performance of steel buildings with seismic isolator and fixed based steel buildings with damper(Işık Üniversitesi, 2022-01-28) Abdi, Abdullahi Abdiaziz; Umut, Önder; Işık Üniversitesi, Lisansüstü Eğitim Enstitüsü, İnşaat Mühendisliği Yüksek Lisans ProgramıEarthquake causes huge loss of lives and enormous damages to properties every year. In order to understand and avoid such damages, different types of seismic isolators have been used. To get the optimal and effective types of seismic isolators, a comparison study of three same-sized 12-storey steel buildings with conventional steel braced frames, and lead rubber bearing (LRB) fixed-based with fluid viscous dampers (FVD) is conducted and their seismic performance enhancements are evaluated using SAP2000 software. Researchers suggest that the seismic isolator building can survive seismic agitation behaviors such as uplifts, stress against ruptures, shears, cracking and displacements. In the study, three same-sized steel structures with different seismic isolator models, special moment and concentric moment frames of all three structures (SMF and SCBF) respectively, earthquake location (Kocaeli Turkey, Yarimca, 8/17/1999) have been selected, performing non-linear time history analysis, non-linear evaluation of dynamic behavioral building response spectrum analysis under load varying time function and design parameters are conducted. As a result of this study, conventional buildings, lead rubber bearing buildings and fluid viscous damper building storey displacement, inter-storey drifts, mode shape, shear force, axial force, base shear, and time history analysis for nonlinear dynamic structural responses are evaluated and compared with the conventional, lead rubber bearing and fluid viscous damper building, according to American Institute of Steel Construction (AISC 360-16).Yayın An experimental and theoretical work on the seismic behavior of a reinforced concrete frame(Işık Üniversitesi, 2019-01-18) Agyemang, Christabel Akosua Sakyiwaa Osei; Karadoğan, Hüseyin Faruk; Işık Üniversitesi, Fen Bilimleri Enstitüsü, İnşaat Mühendisliği Yüksek Lisans ProgramıCorrosion of reinforcements embedded in concrete is one of the numerous causes of deterioration in reinforced concrete structures. In an earthquake prone region, corroded structures become more vulnerable to early failure within its life cycle.The major difficulty for experimental work on corrosion is related to the preparation of a naturally corroded specimens because it is time consuming hence accelerate corrosion is utilized in many researches. In this study, a 15 year old naturally corroded one storey one bay frame specimen and several standout cylindrical specimens were constructed using unseived sea sand containing seashells and to represent structures built during the rapid urbanization period in last 5 decades. The specimen was tested under reversed cyclic loads and the test results were compared to results achieved previously with no corrosion. Furthermore, a numerical analysis was conducted by existing computer programs (SAP2000 and SeismoStruct) and a pushover algorithm was adapted considering lumped plasticity to obtain the structural response of the specimen by different techniques for two theories of analysis including an algorithm for determining stability loads and period at different states of plastic deformations. All numerical results were compared with the experimental results. 15 year old frame showed moderate corrosion at the lower ends of the columns with the lateral load capacity and ultimate displacement not extremely affected by the corrosion. However, higher energy dissipation capacity was observed and with low lateral stiffness at low levels of displacement. Aside the study on corrosion on the frame specimen, this thesis developed a correlation between Poisson’s ratio and nonlinearity index ? based on the gathered empirical data on the uniaxial compression test of 15 year old cylindrical specimens.
