İnşaat Mühendisliği Bölümü Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/205

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Alkali activation of mortars containing different replacement levels of ground granulated blast furnace slag
(ELSEVIER SCI LTD, 2012) Bilim, Cahit; Atis, Cengiz Duran; 0000-0003-3459-329X; AGÜ, Mühendislik Fakültesi, İnşaat Mühendisliği Bölümü; Atis, Cengiz Duran
The aim of the present study is to investigate some properties of alkali-activated mortars containing slag at different replacement levels. Ground granulated blast furnace slag was used at 0%, 20%, 40%, 60%, 80% and 100% replacement by weight of cement, and liquid sodium silicate having three different Na dosages was chosen as the alkaline activator. In this research, carbonation resistance measurements and compressive and flexural strength tests were performed on the mortar specimens with size of 40 40 160 mm. The findings obtained from the tests showed that carbonation depth values of the mortars decreased with the increase of activator dosage. Additionally, compressive and flexural strength values increased with the increase in activator concentration and slag replacement level. Portland cement/slag mortars activated by liquid sodium silicate exhibited lower strength than the slag alone activated by the same activator.
Analysis of the best available techniques for wastewaters from a denim manufacturing textile mill
(ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD24-28 OVAL RD, LONDON NW1 7DX, ENGLAND, 2017) Yukseler, H.; Uzal, N.; Sahinkaya, E.; Kitis, M.; Dilek, F. B.; Yetis, U.; AGÜ, Mühendislik Fakültesi, İnşaat Mühendisliği Bölümü; Uzal, Nigmet
The present study was undertaken as the first plant scale application and evaluation of Best Available Techniques (BAT) within the context of the Integrated Pollution Prevention and Control/Industrial Emissions Directive to a textile mill in Turkey. A "best practice example" was developed for the textile sector; and within this context, BAT requirements for one of the World's leading denim manufacturing textile mills were determined. In order to achieve a sustainable wastewater management; firstly, a detailed wastewater characterization study was conducted and the possible candidate wastewaters to be reused within the mill were identified. A wastewater management strategy was adopted to investigate the possible reuse opportunities for the dyeing and finishing process wastewaters along with the composite mill effluent. In line with this strategy, production processes were analysed in depth in accordance with the BAT Reference Document not only to treat the generated wastewaters for their possible reuse, but also to reduce the amount of water consumed and wastewater generated. As a result, several applicable BAT options and strategies were determined such as reuse of dyeing wastewaters after treatment, recovery of caustic from alkaline finishing wastewaters, reuse of biologically treated composite mill effluent after membrane processes, minimization of wash water consumption in the water softening plant, reuse of concentrate stream from reverse osmosis plant, reducing water consumption by adoption of counter-current washing in the dyeing and finishing processes. The adoption of the selected in-process BAT options for the minimization of water use provided a 30% reduction in the total specific water consumption of the mill. The treatability studies adopted for both segregated and composite wastewaters indicated that nanofiltration is satisfactory in meeting the reuse criteria for all the wastewater streams considered. (C) 2017 Elsevier Ltd. All rights reserved.
Analysis of the probability of failure for open-grown trees during wind storms
(ELSEVIER SCI LTD, 2014) Ciftci, Cihan; Arwade, Sanjay R.; Kane, Brian; Brena, Sergio F.; 0000-0001-9199-6437; AGÜ, Mühendislik Fakültesi, İnşaat Mühendisliği Bölümü; Ciftci, Cihan
Although trees convey important environmental, economic, and sociological benefits on humans and society, they can also cause significant economic and societal disruptions, especially when subjected to wind storms in urban environments. Tools for proper assessment of the risk of these disruptions can be of significant benefit to society. In this research an approach to quantifying the failure probability for trees subject to wind storms is presented and illustrated by application to two specific maple trees in Massachusetts, USA. The approach entails four specific steps: (1) Random wind time history samples were generated using a modified Ochi–Shin spectrum, (2) these wind time histories were used as loading time histories on finite element models of the example trees in both summer (in-leaf) and winter (leafless), (3) maximum bending moments generated by the random wind time histories were compared to the failure (yield) moment of the tree at 1.4 m above ground, (4) the failure/fragility curves of the trees were estimated by Monte Carlo simulation for a range of average wind speeds and for 1000 independent wind time histories at each wind speed.
Application of Smoothed Particle Hydrodynamics to Structural Cable Analysis
(MDPI, ST ALBAN-ANLAGE 66, CH-4052 BASEL, SWITZERLAND, 2020) Dincer, A. Ersin; Demir, Abdullah; AGÜ, Mühendislik Fakültesi, İnşaat Mühendisliği Bölümü
In this study, a numerical model is proposed for the analysis of a simply supported structural cable. Smoothed particle hydrodynamics (SPH)-a mesh-free, Lagrangian method with advantages for analysis of highly deformable bodies-is utilized to model a cable. In the proposed numerical model, it is assumed that a cable has only longitudinal stiffness in tension. Accordingly, SPH equations derived for solid mechanics are adapted for a structural cable, for the first time. Besides, a proper damping parameter is introduced to capture the behavior of the cable more realistically. In order to validate the proposed numerical model, different experimental and numerical studies available in the literature are used. In addition, novel experiments are carried out. In the experiments, different harmonic motions are applied to a uniformly loaded cable. Results show that the SPH method is an appropriate method to simulate the structural cable.
Ardıl Baraj Yıkılmasının Mansapta Bulunan Elastik Yapı Üzerindeki Etkisinin Yapı-Sıvı Etkileşim Yöntemi ile İncelenmesi
(Iğdır Üniversitesi, 2020) Dincer, Ali Ersin; Demir, Abdullah; 0000-0002-4662-894X; 0000-0002-6392-648X; AGÜ, Mühendislik Fakültesi, İnşaat Mühendisliği Bölümü; Dincer, Ali Ersin; Demir, Abdullah
Bu çalışmada yazarlar tarafından geliştirilen bir yapı-sıvı etkileşim yöntemi idealize edilmişardıl baraj yıkılması problemi için test edilmiştir. Bu doğrultuda geliştirilen yöntemde, sıvı kısımyumuşatılmış tanecik hidrodinamiği (smoothed particle hydrodynamics - SPH) ile, katı kısım ise sonluelemanlar (finite element – FE) yöntemi ile modellenmiş ve katı ile sıvı arasındaki akupaj, kontakmekanik kullanılarak gerçekleştirilmiştir. Aynı geometrideki ardıl barajlar aralarında mesafebırakmaksızın yerleştirilmiştir. En yüksek konumdaki barajın doluluk oranındaki değişim dikkatealımıştır. Yıkılan barajların mansaptaki elastik bir yapıya etkisi hem yapının deformasyonu yönündenhem de akışkandaki basınç dağılımları yönünden test edilmiştir. Ayrıca serbest akışkan yüzeyi profillerive su hızı profilleri de çalışmada sunulmuştur.
Arsenic removal by the micellar-enhanced ultrafiltration using response surface methodology
(IWA PUBLISHING, ALLIANCE HOUSE, 12 CAXTON ST, LONDON SW1H0QS, ENGLAND, 2020) Gokcek, Oznur Begum; Uzal, Nigmet; 0000-0002-0912-3459; 0000-0003-1730-2905; AGÜ, Mühendislik Fakültesi, İnşaat Mühendisliği Bölümü
The present research investigates the removal of arsenic (As) from aqueous solutions using micellar-enhanced ultrafiltration (MEUF) by utilizing two different surfactants: benzethonium chloride and dodecyl pyridinium chloride (BCl and DPCl). The impact of the operating variables and maximum removal efficiency were found under different conditions for BCl and DPCl surfactants. The maximum As rejection efficiency for MEUF with BCl and DPCl surfactants is 92.8% and 84.1%, respectively. In addition to this, a statistics-based experimental design with response surface methodology was used for the purpose of examining the impact of operating conditions, including initial pH, initial As concentration (ppb), and surfactant concentration (BCl, mM) in As-removal from aqueous solutions. In the analysis of the experimental data, a second-order polynomial model that was validated by statistical analysis for the BCl surfactant was used. On the basis of the response model created, the removal of As ions was acquired at optimum operating parameters, including the initial As concentration of 150 ppb, surfactant concentration of 5 mM and pH 10 for the BCl surfactant with 92.8% As-removal efficiency.
Arsenic removal from aqueous solutions by ultrafiltration assisted with polyacrylamide: an application of response surface methodology
(DESALINATION PUBL, 2015) Varol, Bekir; Uzal, Nigmet; 0000-0002-0912-3459; AGÜ, Mühendislik Fakültesi, İnşaat Mühendisliği Bölümü; Uzal, Nigmet
The present work deals with removal of arsenic from aqueous solutions by ultrafiltration assisted with polyacrylamide as an environmental friendly complexing polymer. The system performance was evaluated in relation to quality of permeate in terms of operating variables as feed concentration of arsenic ions (C-o, gL(-1)), ratio of polymer to arsenic (r, w/w), and pH of feed solution. The effect of the operating variables and maximum arsenic removal efficiency was determined by adopting design of experiments and response surface methodology under different conditions for this polymer. The experimental data were analyzed with a second order polynomial model validated by statistical analysis. Based on the response model developed, the maximum removal efficiency, close to 100%, of arsenic ions has been obtained at optimum operating parameters as C-o: 150 gL(-1), r: 2, and pH 10.
Assessment of the effectiveness of a rockfall ditch through 3-D probabilistic rockfall simulations and automated image processing
(ELSEVIERRADARWEG 29, 1043 NX AMSTERDAM, NETHERLANDS, 2021) Akin, Mutluhan; Dincer, Ismail; Ok, Ali Ozgun; Orhan, Ahmet; Akin, Muge K.; Topal, Tamer; AGÜ, Mühendislik Fakültesi, İnşaat Mühendisliği Bölümü; Akin, Muge K.
Rockfall ditches or catchment areas aim to collect falling blocks at the toe of a source zone by dissipating the energy of blocks in an excavated trench. The effectiveness of a rockfall ditch is simply expressed by its block catchment performance and can be evaluated by empirically using existing design charts as well as rockfall simulations. Although 2-dimensional (2-D) analysis has been executed to assess the catchment ditch effectiveness in engineering practice, 3-dimensional (3-D) rockfall models have not received enough attention so far. In this study, the effectiveness of a considerably long rockfall ditch to protect a settlement from falling rocks was assessed on the basis of 3-D rockfall analyses executed using high-resolution digital surface models. The rockfall ditch efficiency was found to be moderate to limited for various segments considering the percentage of blocks not trapped by the ditch. Moreover, the sensitivity of ditch efficiency to ditch depth was analyzed by automated image processing method as well. Additionally, a particular section of ditch alignment was fictitiously excavated or filled by synthetic Digital Surface Model (DSM) generation through image processing. 3-D rockfall modeling carried out using the DSMs with synthetically manipulated ditches points out that the effectiveness of a catchment ditch is highly depended upon ditch depth. Even a small volume of block accumulation inside the ditch definitely reduces the ditch performance resulting extended runout distances reaching to residential area. Finally, 3-D rockfall modeling is accepted to be an effective tool to rate the efficiency of existing rockfall ditches and synthetically generated ditches on DSMs (or DEMs) by means of automated image processing method may assist the control of current ditch dimension as well as new catchment ditch design.
Batık Minarelerde Su Seviyesinin Yapıya Olan Etkisinin Sayısal Olarak İncelenmesi
(Iğdır Üniversitesi, 2021) Demir, Abdullah; Dinçer, Ali Ersin; 0000-0002-6392-648X; 0000-0002-4662-894X; AGÜ, Mühendislik Fakültesi, İnşaat Mühendisliği Bölümü; Demir, Abdullah; Dincer, Ali Ersin
Baraj göllerinin, sular altında bıraktığı yerleşim yerlerinin, su üstünde kalan son mirasları minarelerdir. Türkiye’de iki adet batık minare bulunmaktadır ve su üstünden görülebilmeleri ile cazibe merkezleri haline gelmişlerdir. Uzun yıllar sular altında kalması bu yapıların malzeme kalitesinin düşmesine sebep olmuştur/olacaktır. Bunun yanında; olası bir deprem esnasında var olan zemin hareketine ek olarak suyun çalkalanma etkisinin de eklenmesi bu minarelerin davranışlarının öngörülmesini daha da zorlaştırmaktadır. Yüksek Deprem riski barındıran bölgelerde yer alan her bu yapıların deprem esnasında su ile yapacağı etkileşimin sonuçlarının irdelenmesi gerekmektedir.Bu kapsamda su altında kalan minarelerin davranışlarını incelemek için idealleştirilmiş 2 boyutlu model oluşturulmuş ve yakın fay hareketleri uygulanmıştır. İdealleştirilmiş modelin analizi için tam akupajlı bir yapı-sıvı etkileşim (FSI) modeli kullanılmıştır. Bu modelde yapı kısmın modellenmesi için sonlu elemanlar yöntemi (FEM), sıvı kısmın modellenmesi için ise yumuşatılmış parçacık hidrodinamiği (SPH) kullanılmıştır. Bu iki farklı yöntem ile modellenen alanların etkileşimi için ise kontak mekanik kullanılmıştır. Kullanılan FSI yöntemi birçok problemin çözümü ile doğruluğu kanıtlanan geçerli bir yöntemdir. Farklı su seviyeleri ile oluşturulan idealleştirilmiş modeller, geliştirilen FSI yöntemi ile analiz edilmiş ve sonuçlar karşılaştırmalı olarak sunulmuştur. Elde edilen sonuçlar batık minarelerde su kütlesi etkisinin yakın fay altında ne kadar yüksek olduğunu ortaya koymaktadır. Su seviyesindeki değişim ile bu etki doğal olarak değişim göstermektedir. Çalışma kapsamında farklı su seviyeleri incelenerek batık minareler üzerindeki su kütlesi etkisi ayrıntılı olarak incelenmiştir.
Carbon Dioxide Absorption Using Different Solvents (MEA, NaOH, KOH and Mg(OH)2) in Bubble Column Reactor
(Bitlis Eren Üniversitesi, 2023) Gül, Ayşe; Tezcan Un, Umran; 0000-0002-2305-6408; AGÜ, Mühendislik Fakültesi, İnşaat Mühendisliği Bölümü; Gül, Ayşe Ayşe; Tezcan Un, Umran
Carbon dioxide is considered to be one of the greenhouse gases potentially responsible for climate change. The aim of this research is to reduce emissions by capturing carbon dioxide in a solution using an absorption method. The absorption capacity, absorption rate, carbon dioxide removal efficiency, and overall mass transfer coefficient of MEA (Monoethanolamin) and alkaline solvents (NaOH, KOH, Mg (OH)2) were investigated using a bubble column gas absorption reactor with counter current flow. The effects of operational parameters such as solvent concentration (0.01, 0.05, and 0.25M) and solvent type were studied. The research showed that KOH, NaOH, and MEA were more efficient in capturing CO2 than Mg (OH)2 was. For all solvent types, the total mass transfer coefficient, absorption rate, and CO2 removal efficiency were increased with the increase in the concentration of solvent. The solvent concentration is increased from 0.01 M to 0.25 M to obtain the highest KGa values for MEA, NaOH, and KOH, 3.75 1/min for MEA, 3.70 1/min for NaOH, and 3.93 1/min for KOH.The MEA, NaOH, and KOH absorption rates were maximum at 0.25 M solvent concentrations as 0.19x103 mol/Ls. The maximum CO2 removal efficiencies for MEA, NaOH, and KOH at 0.25 M solvent concentration are greater than 60%. Absorption capacity of NaOH and KOH is 0.313 mol CO2/mol NaOH and 0.316 (mol CO2/mol KOH). The highest absorption capacity, 0.576 mol CO2/mol MEA, was obtained at a solvent concentration of 0.01M MEA.
Carbon dioxide absorption using monoethanolamine, piperazine and n-metil-2-pirolidon solvents under counter current regime in packed column reactor
(ELSEVIER SCI LTD, 2024) Gul, Ayse; Barış, Mesut; Un, Umran Tezcan; 0000-0002-2305-6408; AGÜ, Mühendislik Fakültesi, İnşaat Mühendisliği Bölümü; Gul, Ayse
In this research the carbon dioxide absorption using Monoethanolamine (MEA), Piperazine (PZ) and N-Metil-2-pirolidon (NMP) solvents and their different blends (MEA/NMP, PZ/NMP, MEA/PZ) in packed column reactor filled with Raschig rings was investigated and compared for efficient carbon dioxide absorption. The process was followed in a countercurrent regime under a liquid flow rate of 200 mL/min, gas flow rate of 2.5 L/min, and CO2 concentration of 50,000 ppm. Carbon dioxide removal efficiency (%), absorption capacity (mol CO2/mol solvent), overall mass transfer coefficient (1/min) and absorption rate (mol/l.s) were monitored. The highest obtained values for carbon dioxide removal efficiency, absorption capacity and overall mass transfer coefficient were 57.5%, 0.148 mol CO2/mol solvent and 2.178 min-1 respectivelly when 0.03 M MEA/0.07 M PZ in a hybrid system was used. It was concluded that PZ blends with MEA were successful absorbent as the organic physical solvent whereas NMP didn't show improving effect in blends with MEA on the absorption efficiency.
Characteristics of calcined natural zeolites for use in high-performance pozzolan blended cements
(ELSEVIER SCI LTD, 2014) Uzal, Burak; Kucukyildirim, E; 0000-0002-3810-7263; AGÜ, Mühendislik Fakültesi, İnşaat Mühendisliği Bölümü; Uzal, Burak
Two natural zeolites with different characteristics were calcined at various temperatures in order to improve the benefits provided by their use in blended cements as cement replacement material. Natural zeolites were firstly characterized for their crystallinity by X-ray diffraction analysis, specific surface area by nitrogen absorption, and pozzolanic activity by electrical conductivity method, before and after the calcination. In order to assess the performance of calcined natural zeolite as cement replacement material, blended Portland cement pastes and mortars with raw and calcined zeolites were tested for their water requirement, free lime content, pore size distribution and compressive strength. The experimental results indicated that calcined zeolites are more desirable with lower water requirement and higher strength performance as cement replacement material than the raw zeolites. Blended cement with calcined natural zeolite showed higher compressive strength performance, when compared to that with the raw zeolite due to decreased porosity and refined pore structure of the hardened cementitious system
Characterization of Limestone Calcined Clay Cement Made with Calcium Sulfoaluminate Clinker
(SPRINGER, 2024) Atasever, Muhammet; Erdoğan, Sinan Turhan; 0000-0001-7375-8152; AGÜ, Mühendislik Fakültesi, İnşaat Mühendisliği Bölümü; Atasever, Muhammet
This study concentrated on producing limestone calcined clay calcium sulfoaluminate cement by replacing portland cement in limestone calcined clay cement with calcium sulfoaluminate cement, with the goal of increasing the early strength of limestone calcined clay cement. The mineralogy and microstructures of hydrating pastes were investigated using x-ray diffraction and scanning electron microscopy. Heat evolution was studied using isothermal calorimetry. Strength development and workability were assessed on mortar samples. The 1 day strengths of limestone calcined clay calcium sulfoaluminate cement samples exceeded those of limestone calcined clay cement by ~ 30–80%, though its strength gain slows significantly after 1 day due to the lack of calcium silicates, affecting pH and clay dissolution. Despite this, the strength development of limestone calcined clay calcium sulfoaluminate cement, when adjusted for CO2 emissions, is comparable to limestone calcined clay cement. Additionally, limestone calcined clay calcium sulfoaluminate cement provides a 10–15% higher flow and exhibits a lower heat of hydration beyond 12 h, while maintaining a production cost similar to that of limestone calcined clay cement.
Characterizing boron-enhanced one-part alkaline-activated mortars: Mechanical properties, microstructure and environmental impacts
(ELSEVIER, 2024) Örklemez, Ezgi; İlkentapar, Serhan; Durak, Ugur; Gülçimen, Sedat; Uzal, Niğmet; Uzal, Burak; Karahan, Okan; Atiş, Cengiz Duran; 0000-0002-8967-3484; 0000-0002-3810-7263; AGÜ, Mühendislik Fakültesi, İnşaat Mühendisliği Bölümü; Gülçimen, Sedat; Uzal, Niğmet; Uzal, Burak
Since alkali activators negatively effect the environmental impact assessment, it is necessary to develop the alternative activators from natural sources with low environmental impact. Therefore, in this study, the usage of boron refined products colemanite, ulexite and boron pentahydrate as activators in slag-based alkali-activated mortar systems was investigated in detail. Flexural and compressive strength tests, isothermal calorimetry measurement, thermogravimetric and differential thermal analysis, inductively coupled plasma mass spectrometry analysis, field emission scanning electron microscopy, and energy dispersive analysis and elemental mapping and X-ray diffraction analysis were carried out on the samples. In addition, sample production was subjected to life cycle analysis (LCA) with a cradle-to-gate approach using two different transportation scenarios. According to the results obtained, it was determined that colemanite, ulexite and boron penta hydrate, when used in optimum proportions, had a positive effect on strength (up to increase 40% compressive strength by 20% ulexite replacement) and could be used as an activator in slag-based alkali-activated systems. The positive results obtained in strength as a result of using boron-refined products are also supported by other test results conducted within the scope of the study. Furthermore, according to the LCA results, it was observed that there was a significant decrease in global warming potential with the substitution of 20% colemanite, ulexite or boron pentahydrate as activators, not only compared to the reference sample but also traditional cementitious systems.
A cleaner demolition scheduling methodology considering dust dispersion: A case study for a post-earthquake region
(ELSEVIER, 2024) Dincer, Ali Ersin; Demir, Abdullah; Dilmen, Omer; 0000-0002-4662-894X; 0000-0002-6392-648X; 0000-0002-7494-8625; AGÜ, Mühendislik Fakültesi, İnşaat Mühendisliği Bölümü; Dincer, Ali Ersin; Demir, Abdullah; Dilmen, Omer
In the present century, pollution is a primary concern for billions, prompting governments to advocate cleaner ways of production. Demolition activity is often an indispensable solution for structures that have completed their economic life. However, there are no regulations for the scheduling of demolition, except those related to the method of demolition and ensuring worker safety. Older buildings incorporate hazardous materials, such as asbestos, silica, and lead. These materials not only carry inherent risks, but high levels of aerosols in the air also adversely affect health. In this study, a demolition scheduling method is proposed, considering the dust dispersion. This research is pioneering, providing a structured demolition schedule to minimize the impact on both humans and the environment. In the methodology, a dispersion model is used to calculate the region exposed to dust and the concentration distribution throughout that area. In addition to the dust effect map, a vulnerability map is created using Analytical Hierarchy Process (AHP), aiding in determining interrelations between vulnerable sites. Thus, the dust effect map is derived by considering both dust exposure and the vulnerability map. The region affected by dust and the concentration of dust vary based on wind characteristics. By knowing the dust effect maps for the site (or all subsites) during specified time periods, a schedule can be defined. As a case study, schedules causing the absolute minimum and optimum dust effect rates are established for Kahramanmaras,, , , T & uuml;rkiye which recently experienced a devastating earthquake. The findings of the case study show that the dust effect on humans and the environment is significantly reduced. Consequently, by adhering to the proposed scheduling plan, human exposure to demolition dust is minimized, resulting in reduced medical expenses even without increasing the cost of the demolition.
Comparative analysis of hybrid geothermal-solar systems and solar PV with battery storage: Site suitability, emissions, and economic performance
(ELSEVIER, 2024) Fedakar, Halil Ibrahim; Dinçer, Ali Ersin; Demir, Abdullah; 0000-0002-7561-5363; 0000-0002-4662-894X; 0000-0002-6392-648X; AGÜ, Mühendislik Fakültesi, İnşaat Mühendisliği Bölümü; Fedakar, Halil Ibrahim; Dinçer, Ali Ersin; Demir, Abdullah
Renewable energy integration has become a critical focus in the global effort to reduce carbon emissions and diversify energy sources. In regions with distinct geographic features, such as Türkiye, combining different renewable technologies can offer enhanced energy security. This study investigates the site suitability and economic and environmental performance of hybrid geothermal-solar systems and solar PV systems with battery storage across the provinces of Osmaniye, Hatay, and Kilis, of Türkiye. Using the fuzzy-AHP method, site suitability is evaluated, addressing a key gap in comparing these systems' adaptability to varying geographic conditions. This study is the first to directly compare these two renewable energy technologies in terms of site suitability. The findings reveal significant differences in site suitability, with solar PV systems with battery storage demonstrating broader applicability across the region. The suitable sites (20–100 % suitability) cover 1260.82 km² for solar PV systems with battery storage and only 122.18 km² for hybrid geothermal-solar systems. In terms of environmental impact, hybrid geothermal-solar systems exhibit significantly lower carbon emissions, averaging 44.6 kg CO₂/MWh, compared to 123.8 kg CO₂/MWh for solar PV systems with battery storage. Economically, hybrid geothermal-solar systems also outperform with a lower levelized cost of electricity of $0.091 kWh versus $0.254 kWh for solar PV systems. These results highlight the environmental and economic advantages of hybrid geothermal-solar systems, while also emphasizing their limited scalability to regions with geothermal activity. Conversely, solar PV systems, despite their higher emissions and costs, offer greater flexibility and potential for widespread deployment.
Comparative life cycle assessment of retort pouch and aluminum can for ready-to-eat bean packaging
(SPRINGER, 2023) Gulcimen, Sedat; Ozcan, Ozlem; Cevik, Selin Babacan; Kahraman, Kevser; Uzal, Nigmet; 0000-0002-8967-3484; 0000-0002-2786-3944; 0000-0002-0912-3459; AGÜ, Mühendislik Fakültesi, İnşaat Mühendisliği Bölümü; Gulcimen, Sedat; Ozcan, Ozlem; Kahraman, Kevser; Uzal, Nigmet
Since packaging contributes to severe environmental impacts in food production, alternatives of packaging materials that satisfy customer needs while minimizing environmental impacts in a cost-effective manner should be preferred for food product sustainability. This paper compares two different packaging materials (aluminum cans and retort pouches) with a life cycle approach to assess the environmental impacts of ready-to-eat bean packaging. The life cycle assessment (LCA) was used to define and compare the environmental performance of ready-to-eat beans in aluminum cans and retort pouches. The gate-to-gate approach was used in the LCA, with a functional unit of 1 kg of packaged ready-to-eat bean product. Inventory for packaging in retort pouch was created in collaboration with Duru Bulgur Company (Karaman, Turkey) and the data for ready-to-eat beans in the aluminum can were gathered from the literature. The findings show that ready-to-eat beans in retort pouches have lower environmental impacts than ready-to-eat beans in aluminum cans. The packaging and washing processes for both ready-to-eat beans packaged in aluminum cans and retort pouches had the greatest environmental impact. In ready-to-eat beans production, retort pouch provides 87% better environmental performance than aluminum can in terms of global warming (GW). Overall, the results demonstrated that replacing aluminum cans with retort pouches in ready-to-eat bean production can significantly reduce environmental effects in all impact categories.
A Comparative Study on the VS30 and N-30 Based Seismic Site Classification in Kahramanmaras, Turkey
(HINDAWI LTD, ADAM HOUSE, 3RD FLR, 1 FITZROY SQ, LONDON, W1T 5HF, ENGLAND, 2020) Naji, Dalia Munaff; Akin, Muge K.; Cabalar, Ali Firat; 0000-0001-8873-5287; 0000-0002-9279-2257; 0000-0002-0390-5652; AGÜ, Mühendislik Fakültesi, İnşaat Mühendisliği Bölümü
Assessment of seismic site classification (SSC) using either the average shear wave velocity (V-S30) or the average SPT-N values (N-30) for upper 30 m in soils is the simplest method to carry out various studies including site response and soil-structure interactions. Either the V-S30- or the N-30-based SSC maps designed according to the National Earthquake Hazards Reduction Program (NEHRP) classification system are effectively used to predict possible locations for future seismic events. The main goal of this study is to generate maps using the Geographic Information System (GIS) for the SSC in Kahramanmaras city, influenced by both East Anatolian Fault and Dead Sea Fault Zones, using both V-S30 and N-30 values. The study also presents a series of GIS maps produced using the shear wave velocity (V-S) and SPT-N values at the depths of 5 m, 10 m, 15 m, 20 m, and 25 m. Furthermore, the study estimates the bed rock level and generates the SSC maps for the average V-S values through overburden soils by using the NEHRP system. The V-S30 maps categorize the study area mainly under class C and limited number of areas under classes B and D, whereas the N-30 maps classify the study area mainly under class D. Both maps indicate that the soil classes in the study area are different to a high extent. Eventually, the GIS maps complied for the purpose of urban development may be utilized effectively by engineers in the field.
Comparison of Mechanical and Physical Properties of Screed with and without Expanded Polystyrene (EPS) Particles
(YILDIZ TEKNİK ÜNİVERSİTESİ, 2022) Kılıç, Fikret Merih; Yorulmaz, Hediye; Özuzun, Sümeyye; Durak, Uğur; İlkentapar, Serhan; Karahan, Okan; Atiş, Cengiz Duran; 0000-0002-1015-4308; AGÜ, Mühendislik Fakültesi, İnşaat Mühendisliği Bölümü; Yorulmaz, Hediye
In this study, in order to observe the mechanical and physical properties of ordinary screed, sandy-lightweight screed and lightweight screed samples, expanded polystyrene (EPS) was used as fine aggregate and lightweight screed systems were produced by replacing sand at 100%, 50% and 0%. Samples of cement dosages of 250, 300, 350 kg/m3 were produced for lightweight screeds, sandy-lightweight screeds and ordinary screeds. Unit weight, water absorption capacity, flexural strength, compressive strength, fire resistance, abrasion and thermal conductivity tests were performed on the produced screed systems. As a result of the research, it was determined that as EPS ratio increases in screed system; unit weights decreased, water absorption rates increased. Besides, the flexural and compressive strengths, fire and abrasion resistance are also decreased. However, it was observed that the thermal conductivity coefficient reduced with the increment of EPS particles in the screed. In normal, sandy-lightweight and lightweight screeds, it was determined that as the cement dosage increased; the unit weights, flexural and compressive strengths, fire and abrasion resistance increased, water absorption capacity and the thermal conductivity coefficient decreased.
Comparison of SPT and V-s-based liquefaction analyses: a case study in Ercis (Van, Turkey)
(SPRINGER INTERNATIONAL PUBLISHING AG, GEWERBESTRASSE 11, CHAM, CH-6330, SWITZERLAND, 2018) Akkaya, Ismail; Ozvan, Ali; Akin, Mutluhan; Akin, Muge K.; Ovun, Ugur; 0000-0002-7682-962X; 0000-0001-8873-5287; AGÜ, Mühendislik Fakültesi, İnşaat Mühendisliği Bölümü
Liquefaction which is one of the most destructive ground deformations occurs during an earthquake in saturated or partially saturated silty and sandy soils, which may cause serious damages such as settlement and tilting of structures due to shear strength loss of soils. Standard (SPT) and cone (CPT) penetration tests as well as the shear wave velocity (V-s)-based methods are commonly used for the determination of liquefaction potential. In this research, it was aimed to compare the SPT and V-s-based liquefaction analysis methods by generating different earthquake scenarios. Accordingly, the Ercis residential area, which was mostly affected by the 2011 Van earthquake (M-w = 7.1), was chosen as the model site. Ercis (Van, Turkey) and its surroundings settle on an alluvial plain which consists of silty and sandy layers with shallow groundwater level. Moreover, Caldiran, Ercis-Kocapinar and Van Fault Zones are the major seismic sources of the region which have a significant potential of producing large magnitude earthquakes. After liquefaction assessments, the liquefaction potential in the western part of the region and in the coastal regions nearby the Lake Van is found to be higher than the other locations. Thus, it can be stated that the soil tightness and groundwater level dominantly control the liquefaction potential. In addition, the lateral spreading and sand boiling spots observed after the 23rd October 2011 Van earthquake overlap the scenario boundaries predicted in this study. Eventually, the use of V-s-based liquefaction analysis in collaboration with the SPT results is quite advantageous to assess the rate of liquefaction in a specific area.

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