Scopus İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/395
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Book Part Citation - Scopus: 2Properties of Alkali-Activated Lightweight Concrete(Elsevier, 2022) Top, S.; Altiner, Mahmut; Vapur, HüseyinThis chapter presents a brief overview of the properties of alkali-activated lightweight concrete. Nowadays, the production of lightweight concrete has great attentions due to its extraordinary advantages such as reduced mass, improved sound and thermal insulation properties. Furthermore, the low gas emissions and the utilization of waste materials increase the importance of alkali-activated lightweight concrete. In this chapter, the strengths of lightweight concrete were examined by considering the aggregate type and density, the alkali activator type and concentration, the type of fiber reinforcements and foaming agents, which are the factors that have the most impact on the strengths. Thermal conductivity, fire resistance, acoustic performance, and durability properties have been explained considering the key points in the literature. In addition to porosity, it has been determined that one of the most important factors directly affecting the fire resistance is the precursor type. It has been concluded that the fire resistance of the concrete prepared by using K-based precursors is higher. Acoustic performances of alkali-activated lightweight concrete vary. It is necessary to use a high amount of aggregate in order to obtain concretes with wide frequency ranges and high absorption coefficient. Contrary to concrete produced from Portland cement, alkali-activated concrete is more resistant to acid and sulfate attacks, since the formation of gypsum and strength is less. © 2022 Elsevier B.V., All rights reserved.Book Part Citation - Scopus: 1Energy Simulation Optimization for Building Insulation Materials(Springer International Publishing, 2023) Himmetoğlu, Salih; Delice, Yılmaz; Kızılkaya Aydoğan, Emel Kizilkaya; Uzal, Burak; Aydoğan, Emel KızılkayaRecently increased energy consumption and carbon emissions caused by energy consumption have mobilized governments. Energy-efficient building designs have become one of the most fundamental strategies preferred by governments. The heating and cooling demands have an important share in energy consumption in buildings. Therefore, thermal insulation systems have become the basic building elements to design energy-efficient buildings. Determining suitable thermal insulation strategies for energy-efficient structures built in different climates is an important decision problem for designers. This study aims to select insulation material and insulation thickness for energy-efficient building design. The stone wool, extruded polystyrene (XPS) insulation materials, and their alternative thicknesses are considered for Turkey’s two different climate zones. The Energy Plus and Design Builder energy simulation programs are used to analyze all alternatives. A decision support system is generated by considering both the material cost and the heating and cooling energies to be consumed during the building life cycle. The most suitable insulation material for the first zone is stone wool, and its thickness is 10 cm. The most suitable insulation material for the second zone is stone wool, and its thickness is 10 cm. The total saving is 11% for the building in the first zone. The total saving is 9% for the building in the second zone. The generated designs have been quite stimulating for decision-makers. © 2024 Elsevier B.V., All rights reserved.Conference Object Citation - Scopus: 1Air Gun With Water Bullet(Eindhoven University of Technology, 2023) Bozkuş, Zafer; Dinçer, A. Ersin; Tijsseling, A. S.; van de Ven, Alphons A.F.; van de Ven, FonsThe gun is a 12 m long inclined pipe of 0.1 m diameter which is connected to a charge of compressed air contained in a 0.5 m3 vessel. The bullet is a slug of water sitting in the upstream lower end of the pipe. The trigger is a hand-operated valve. The target is an elbow at the upstream higher end of the pipe. The smoking gun effect is created by a mist of water coming out of the pipe after each shot. The apparatus is not a toy but meant for serious research. When steam lines are out of operation and/or lack thermal insulation, liquid water collects in the lower parts of the system. System restart may accelerate the water slugs to velocities as high as 50 m/s, and subsequent slug impacts on elbows and orifices may cause pressure peaks with magnitudes only encountered in water-hammer events. The experimental programme consists of water slugs fired towards an elbow with an open end, a closed end, and an orifice end. The varied parameters are air pressure, water mass, outlet condition (open, closed, orifice). Upstream driving pressure and downstream impact pressure are measured in each experimental run. Pressure peaks up to 50 bar have been observed. Experimental results are compared with preliminary predictions from basic one-dimensional models. © 2024 Elsevier B.V., All rights reserved.