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Öğe Development of Finite Element Model for a Special Lead Extrusion Damper(2021) Güllü, Ahmet; Çalım, Furkan; Yüksel, Ercan; Soydan, CihanA significant amount of seismic energy is imparted to the structures during earthquakes. Theenergy spreads within the structure and transforms in various energy forms as dissipatedthrough the structure. The conventional seismic design provides specific ductile regions,namely plastic hinges, on structural elements. Therefore, the energy dissipation capacities ofthe structural elements and the structure enhance. However, this approach accepts that thedeformations will concentrate on the plastic hinge zones and severe damage may occur onstructural elements within deformation limits that are defined by the seismic codes. The modernseismic design aims to dissipate a large portion of the seismic input energy by installing energydissipating devices (EDDs) to the structure. Thus, deformation concentrates on EDDs whichcan be replaced after an earthquake, and energy demand for structural elements is decreased.Lead extrusion damper (LED) is a passive EDD that utilizes the hysteretic behavior of lead. Inthis paper, the preliminary results of the developed three-dimensional finite element model(FEM) for a LED is presented. The results obtained from the finite element analysis (FEA) werecompared with the experimental ones in which LEDs were exposed to sinusoidal displacements.Also, the applicability of the developed FEM was checked for different component dimensionsgiven in the literature. The comparison study yielded a satisfactory consistency. Additionally,the maximum relative difference obtained for the literature devices was reduced to 12% from39% by the developed FEM.Öğe The efficiency of photovoltaic panels to meet energy demand of a school building in the Mesopotamia region(2022) Al-Rubaii, Shaimaa; Köse, Ali; Kazar, Gökhan; Güllü, AhmetAll kinds of energy are one of the basic requirements in life to sustain it. Therefore, the majority of research and applications have been mostly focused on self-sufficient energy or zero-energy buildings in developed countries. Most of these countries encounter energy demand and suffer from carbon dioxide emissions from existing buildings. Energy-efficient applications must be also spread across developing and undeveloped countries especially in the Mesopotamia region due to the hot climate. Hence, the efficiency of a common practice, implementation of photovoltaic panels (PVs), in Iraq is investigated in this study. PVs were designed and empirically implemented in an existing conventional primary school building in Baghdad, Iraq as a case study for the Mesopotamia region. The sustainability and energy analysis of a school building was conducted in diverse scenarios to explore the potential of energy-saving and payback period of the PVs. The slope and number of PV panels located on the school building are the parameters of the current study. Results showed that PV panels with a 30° inclination angle reduced the energy cost of the building by 50%. The payback for the implementation of PVs can be obtained approximately in 8 years. Consequently, the PVs have major potential in energy efficiency and can be implemented in governmental buildings such as public-school buildings in the Mesopotamia region. Besides, society and private institutions may become aware of the importance of sustainable energy with this study. With this case study, the importance of taking advantage of solar energy has been emphasized for undeveloped countries.Öğe Evaluation of the Relation between Seismic Input Energy and Spectral Velocity(2020) Güllü, AhmetEnergy based seismic design concept is getting attention owing to its advantages over theconventional methodologies. Particularly, the consideration of duration and frequency content ofthe earthquake record are chief superiority of the concept. For this original design procedure,accurate determination of seismic input energy is crucially important. Because of solving energybalance equation is a tedious job, the seismic input energy is determined in terms of equivalentvelocity in the literature mostly. However, it was also shown that this relation is valid for onlyundamped systems. Therefore, this study aims to provide the nonsteady relation between seismicinput energy and equivalent velocity for damped systems. Intensive response history analyseswere performed by using plenty of earthquake records those were selected by considering theimpulsive characteristics (ordinary and pulse-like) and shear wave velocity. It was found that therelation given in the literature for seismic input energy and spectral velocity relation is not true fordamped systems. Dependently, it is proposed a set of coefficients considering structural dampingproperties to modify the existing relation.