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Öğe Numerical Analysis of Geotechnical Seismic Isolation System for High-Rise Buildings(Malatya Turgut Özal Üniversitesi, 2021) Yıldız, ÖzgürSeismic isolation is a method of protecting buildings from earthquake-induced deformations by using isolators and devices under the superstructure. The purpose of the seismic isolation method is to reduce the earthquake forces transferred from the ground to the structure by placing energy-absorbing elements between the foundation and superstructure. Especially in developing countries, the "Geotechnical Seismic Isolation (GSI)" system has been proposed as an isolation method to reduce earthquake-induced damages on buildings. This study, it is aimed to reduce the effects of earthquakes in a multi-story building with an isolation layer formed by a rubbersand mixture (RSM). For this purpose, a 10-story reinforced concrete building was numerically modeled. Beneath the foundation of the building model, a seismic energy absorbent RSM layer was placed and its contact with the natural soil was interrupted by using geosynthetic liners. The model was subjected to the 1992 Erzincan (EW) Earthquake motion and its performance has been evaluated in terms of lateral displacements and accelerations. The numerical studies indicated a substantial improvement due to the use of the RSM layer. The accelerations measured by the superstructure decreased up to 48% by employing the isolation layer. The numerical analysis was carried out using the dynamic module of the PLAXIS 2D finite element analysis programÖğe Farklı Linyitlerin Kısa Ve Elementel Analiz Verilerine Dayanarak Üst Isıl Değerlerinin Hesaplanması(Konya Tektik Üniversitesi, 2022) Aksoğan Korkmaz, AydanKatı bir yakıtın ısıl değeri, birim ağırlıktaki yakıtın tamamen yanması sonucu açığa çıkan ısı biriminin sayısıdır. Bir kömürün ısıl değeri, türüne ve organik yapısına karışmış olan yanmayan maddelerin miktarına bağlıdır. Isıl değer, kömür türü yanında, kömür kül ve nem oranı tarafından da belirlenmektedir. Kömürün üst ısıl değeri kalorimetre ile, kömürün bir kalorimetre bombası içinde, basınç altında oksijen ile sabit hacimde yakılması ve oluşan ısının ölçülmesi esasına dayanmaktadır. Literatürde, kısa ve elementel analizlere dayanarak, üst ısıl değer hesaplaması yapabilmek için çeşitli denklemler geliştirilmiştir. Bu çalışmada 10 farklı linyit örneğinin ısıl değeri, hem deneysel olarak belirlenmiş hem de analiz verileri yardımıyla farklı denklemler kullanılarak hesaplanmıştır. Her bir kömür için, deneysel ve hesapla elde edilen üst ısıl değerler karşılaştırılmıştır. En iyi regresyon katsayısı değerleri (R2), kısa analiz ve elementel analiz modelleri için sırasıyla 0.7543 ve 0.5927 olarak belirlenmiştir. Modellerden elde edilen üst ısıl değerlerin, deneysel olarak hesaplananlarla uyum içinde olmadığı görülmüştür.Öğe Kenevir Atıklarının Karbonizasyonu ve Aktif Karbon Eldesi(Konya Teknik Üniversitesi, 2022) Aksoğan Korkmaz, Aydan; Önal, YunusBu araştırmada; bilimsel çalışmalarda kullanılmak üzere Malatya Turgut Özal Üniversitesi Ziraat Fakültesi bünyesinde yetiştirilen kenevir bitkisinin atık kısımları (kök, gövde ve diğer) değerlendirilmiştir. Kenevir atıklarından karbonizasyon ile kimyasal aktivasyon yöntemi kullanılarak aktif karbon elde edilmiş ve karakterizasyon deneyleri gerçekleştirilmiştir. Elde edilen aktif karbonların karakterizasyonunu belirlemek için elementel (C, H, N, S) analiz, XRD, FTIR ve SEM analizleri gerçekleştirilmiştir. Ayrıca, aktif karbonların BET azot adsorpsiyonu yüzey alanı ölçümü ile yüzey alanı ve gözenekliliği belirlenmiştir. Karbonize edilmiş kenevir atığında toplam yüzey alanı (Stotal) 171,75 m2/g, mikrogözenek alanı (Smikro) 145,46 m2/g ve mezogözenek alanı (Smezo) 26,29 m2/g iken bu değerler 1:4 oranında KOH emdirilmiş aktif karbonda sırasıyla 1881,80 m2/g, 1152,40 m2/g ve 728,40 m2/g olarak hesaplanmıştır. Karbonize üründe 0,077 cm3/g olan gözenek hacmi, aktif karbonda 0,8852 cm3/g olarak belirlenmiştir. Karbonize ürün ve aktif karbonun ortalama gözenek çapları (dp) sırasıyla 1,78 nm ve 1,88 nm olarak belirlenmiştir. Bu sonuçlara göre, kenevir atıklarının karbonizasyonu ve kimyasal aktivasyonuyla ekonomik olarak aktif karbon elde edilmesinin mümkün olabileceği belirlenmiştir.Öğe Geological, Mineralogical, Geochemical Properties, and Characterization of Marine Zeolite(2021) Ceylan, ÇiğdemThe study investigates marine Hekimhan (Malatya) zeolites. The unit was sandstone interlayered, green, hard, fine-thicklayered (5-500 cm), and fine-laminated. Its type section has a thickness of 37 m and has a consistency of 24 km in the lateral direction. Mineralogical and structural analyses such as X-Ray Diffraction (XRD), X-Ray Fluorescence (XRF), Scanning Electron Microscopy (SEM), and Fourier Transform Infrared Spectroscopy (FTIR), Differential Thermal Analysis (DTA) and Thermogravimetric Analysis (TGA), and Brunauer-Emmett-Teller (BET) analysis were performed to carry out the physical, chemical, and mineralogical characterization of the examined zeolite. Moreover, grain size distribution, consistency limits, specific weight, and pH values were determined. The results of the XRD analysis showed that the main mineral was clinoptilolite-type zeolite. In addition, the calcite mineral was detected. The SEM images of the zeolite samples revealed a layered microstructure and the BET results revealed that the units had a mesoporous structure.Öğe Determination of the effect of different gravity methods on the removal of ash and sulfur from Arguvan lignite(Alanya Alaaddin Keykubat Üniversitesi, 2020) Aksoğan Korkmaz, Aydan; Bentli, İsmailThis study, it is aimed to find out the beneficiation of Malatya-Arguvan lignite by gravity methods. First of all, the washability of lignite has been investigated with sink-float experiments. It has been determined that lignite washability from washing curves is generally difficult but may be possible with controlled washing at a density of 1.68 g /cm3. Then, to remove ash and sulfur from lignite by shaking table, spiral and Falcon concentrator tests were conducted. Clean coals are obtained from all other methods except Falcon were found to decrease in ash and sulfur content and increase in calorific value. Clean coals with the lowest ash and sulfur content were obtained with a spiral concentrator. Reichert spiral results showed that the ash content decreased from the lignite of 37.77% to 26.50% and the sulfur content from 3.85% to 2.08%. The calorific value increased from 2576 kcal/kg to 4590 kcal/kg. Arguvan lignite has very limited usage due to its lower calorific value, high ash and sulfur content. Although enrichment has been carried out, it has been concluded that lignite needs to be further improved by using different methods.Öğe TBDY-2018’deki Yerel Zemin Koşullarının Çelik Yapı Deprem Davranışına Etkisi Üzerine Bir Çalışma(Bitlis Eren Üniversitesi, 2021) Ülker Peker, Fatma; Işık, ErcanDepremlerin, yapılar üzerindeki etkilerini azaltmak adına yapı-zemin-deprem etkileşiminin gerçekçi olarak ortaya konulabilmesi önemlidir. Bu çalışma kapsamında, Türkiye Bina Deprem Yönetmeliğinde yer alan beş farklı yerel zemin koşulu dikkate alınarak sekiz katlı örnek bir çelik yapı için yapısal analizler gerçekleştirilmiştir. Bu güncel yönetmelik ile birlikte bölgesel bazda kullanılan tasarım spektrumları yerini sahaya özgü spektrumlara bırakmıştır. Bu değişimin yapısal analizlere etkisini koymak adına, 24 Ocak 2020 Sivrice (Elazığ) (Mw=6.8) depremin en çok etkilediği iki yerleşim birimi olan Sivrice (Elazığ) ve Pütürge (Malatya) için elde edilen tasarım spektrumları kullanılarak, her iki yerleşim birimi için de yerel zemin koşulları için analizler ayrı ayrı gerçekleştirilmiştir. Çalışmada ayrıca iki yerleşim biriminin de içerisinde yer aldığı Doğu Anadolu Bölgesinin depremselliği ve son deprem hakkında bilgiler verilmiştir. Bu çalışma sahaya özgü tasarım spektrumlarının ve yerel zemin koşullarının çelik yapılardaki etkisini ortaya koymak adına yapılmıştır.Öğe Utilization of Lignite and Waste Biomass As a Clean Energy Source by Carbonization(2021) Aksoğan Korkmaz, AydanCarbonization is the general name of the process of producing gas, liquid and solid products, especially from fossil fuels such as coal, by heating in an oxygen-free environment. Carbonization is one of the most important transformation processes to obtain high-quality solid (char), gas and liquid products. Fossil-based resources such as coal, petroleum and natural gas are not suitable for long-term use, as they are both limited and harm the environment. Therefore, for energy continuity, it is necessary to benefit from renewable energy sources such as biomass along with fossil fuels. By burning the char obtained from the carbonization of coal and biomass, it is possible to reduce the contents such as SO2 and NOx that pollute the atmosphere. In this study, carbonization experiments of lignite and pistachio shell at different mixing ratios and temperatures was carried out. The higher heating values and C, H, N, S contents of the chars obtained from each experiment were determined. With the increasing temperature and biomass ratio, positive changes have been observed in the obtained clean fuel.Öğe Correlations between SPT, PMT and MASW on Quaternary Alluvial – Fluvial Sediments In Battalgazi, Malatya, Turkey(Malatya Turgut Ozal University, 2020) Ceylan, Çiğdem; Önal, MehmetThe field tests such as the standard penetration test (SPT), pressuremeter test (PMT), and Multi-Channel Analysis of Surface Waves (MASW) give information about the stratigraphic properties, structure, underground water level, bearing capacity, and liquefaction of soil. The studies investigating the correlations between these tests are quite common. Most of the studies found in the literature have focused on sand, silty, and clay soils, while the number of the studies about gravelly soils is limited. In the study area, the gravel content ranged from 0% to 47% depending on local differences. Gravel sizes reached 80 mm at certain locations but remained below it in most locations. In this study, it has been discussed that how correlation studies will change in heterogeneous soils. Among the correlations between the field test results, with the highest R2 value of 0.6847, the strongest correlation was obtained between the PMT-PL value and SPT-N60 value, while, with a R2 value of 0.3906, the weakest correlation was between the PMT-Em value and MASW- Vs value. The low R2 values were attributed to the exceedingly heterogenous structure of the soil and locally changing gravel amounts.Öğe Nonlinear and Equivalent Linear Site Response Analysis of Istanbul Soils(Malatya Turgut Ozal University, 2021) Yıldız, ÖzgürThe effect of local soil characteristics on the propagation of earthquake waves has been commonly studied by researchers. However, the validity of the results obtained by these studies is limited only to the relevant soil conditions. The main purpose of this study is to examine the effect of soil conditions on the propagation of seismic waves in Istanbul. In this regard, soil information belonging to different districts of Istanbul has been compiled. The site response analysis was simulated using a time-domain nonlinear response analysis based on the effective stress method and frequency-domain equivalent linear analysis based on the total stress method. A widely used one-dimensional response analysis program DEEPSOIL was used to estimate the soil response of the sites. Modeled soil profiles were subjected to 1999 Kocaeli earthquake motion and the results of the analysis are presented as spectral acceleration, PGA, and lateral displacements. The results obtained from both of the analyses were evaluated comparatively in terms of the effect of soil properties on the propagation of the seismic waves. The effect of the analysis method based on different approaches on the results is examined. The highlighting results obtained on how the propagation of earthquake waves will be affected by soil conditions. The liquefaction potential of soil profiles was also evaluated using the data of the soil properties of the investigation area.Öğe Investigation of the liquefaction possibility of Ermenek lignite as an alternative clean energy source(Niyazi BULUT, 2021) Aksoğan Korkmaz, AydanCoal liquefaction; can be defined as the transformation of coal into products that have a high energy density, can be easily stored and transported and do not create environmental pollution, to meet both fuel and chemical raw material requirements. This study was carried out to determine the yields of the products formed as a result of the liquefaction of Konya-Ermenek lignite in the N2 atmosphere and under non-catalytic conditions. Proximate and ultimate analysis of the obtained solid and liquid products was made. The composition of the oil product was determined by GC-MS. As a result of liquefaction, the char yield was 71.37%, the preasphaltene yield was 12.24%, the asphaltene yield was 2.23% and the oil + gas yield was 14.16%. It was determined that the higher heating value of 4199 kcal/kg in raw lignite is twice as high in liquefaction products. It was determined that the sulfur content of 3.94% in raw lignite decreased to 1.54%, 0.85% and 0.44% in char, preasphaltene and oil, respectively.Öğe Investigation of the improvement of Sivas-Kangal lignites liquefaction product yields(2021) Aksoğan Korkmaz, Aydan; Bentli, İsmailIn recent years, converting and using coal into the most suitable product according to its properties has emerged as a modern approach. Among the main processes applied to coal are low and high-temperature carbonization, gasification and liquefaction. In coal liquefaction, coal is broken down into free radicals using hydrogen donor solvent and catalyst under high temperature and pressure conditions. Later, these radicals can be used in the production of both liquid fuel and chemical raw materials by being saturated with hydrogen. This study aims to improve the yields of Sivas-Kangal lignite liquefaction products (char, preasphaltene, asphaltene, oil-gas). For this purpose, firstly raw coal, then spiral enriched clean coal liquefaction experiments were carried out. The chemical characterizations of the obtained products were determined by proximate and ultimate analysis. The composition of the oil was identified by GC-MS. As a result of the enrichment, the char yield decreased by 16.5% whereas the oil+gas yield increased by 14.64%. Total conversion increased from 31.74% to 48.24%. It has been concluded that the enrichment process has a positive effect on the liquefaction yields.Öğe Determination of energy damping upon impact load in reinforced concrete sandwich plates with di erent core geometries(Sharif University of Technology, 2021) Savaş, Sedat; Ülker, Mehmet; Turgut, Seval; Bakır, DursunIt can be challenging to analyze Reinforced Concrete (RC) sandwich plates with hollow structures under impact loads in terms of crushing, punching, cracking, and crack trajectories via static and dynamic equations. In the literature, the finite element solutions were provided after determining the behaviors of the materials based on the test results. Therefore, it is required to test the behaviors of RC plates. To this end, the behaviors of sandwich plates under impact loads were experimentally analyzed in this study. The sandwich plates were manufactured by cutting Polyester Foams (PF) into hexagonal prisms, square prisms, I-type, and S-type and installing them inside the RC plates. The manufactured sandwich plates were 27% lighter than full plates. A weight of 320 kg declined freely from 2.5 m, and the load was implemented at the center of the plate at a velocity of 7.5 m/s. Similar implementations were also conducted for filled plates and the maximum displacements were measured in both types of plate tests. The measurements obtained from each test were compared to determine the sandwich plate with the core geometry which provided the highest absorption and the lowest displacement. In the analyses, the S-type core geometry exhibited greater absorption than other core geometries.Öğe Düşük ısıl değerli linyit ve atık biyokütlenin dumansız yakıt olarak kullanılabilirliğinin araştırılması(Bursa Uludağ Üniversitesi, 2021) Korkmaz, Aydan AksoğanEnerji, bir toplumun en önemli temel ihtiyaçlarından biridir. Gelişmekte olan ve az gelişmiş ülkelerdebu enerji ihtiyacının çoğu fosil enerji kaynaklarından karşılanmaktadır. Bu kaynaklar, hem sınırlı hem deçevreyi olumsuz etkiledikleri için, sürekli olarak kullanılmaları uygun değildir. Enerjinin sürekliliği içinbiyokütle gibi yenilenebilir enerji kaynaklarından da maksimum düzeyde faydalanmak gereklidir.Biyokütle; doğrudan yakma, piroliz ve gazlaştırma gibi bazı çevirim teknikleri kullanılarak katı, sıvı ve gazyakıtlara dönüştürülebilmektedir. Biyokütledeki yüksek H içeriği, kömürle birlikte pirolizi sırasındahidrojen kaynağı olarak kullanılmaktadır. Piroliz esnasında biyokütleden yayılan H ve OH radikalleri,kömürün aromatik halkalarındaki kırılmaları desteklemektedir. Kömür ile biyokütlenin pirolizinden eldeedilen katı ürünün yakılmasıyla atmosferi kirleten SO2 ve NOx gibi içeriklerin azaltılması mümkündür. Buçalışmada, linyit ve ceviz kabuğunun farklı karışım oranları ve sıcaklıklarda pirolizi gerçekleştirilmiştir.Elde edilen katı ürünün, kalorifik değerleri ve C, S, N içerikleri belirlenmiştir. Artan biyokütle oranıyla,dumansız yakıtta olumlu değişiklikler olduğu belirlenmiştir.Öğe An IDW-based GIS application for assessment of geotechnical characterization in Erzincan, Turkey(Springer, 2021) Kabalar, Ali Fırat; Karabaş, Bahadır; Mahmutluoğlu, Barış; Yıldız, ÖzgürPreparing maps for geotechnical characterization in earthquake-prone areas is significantly important for decision-makers and local-planners in order to reduce loss of lives. This study presents a series of maps for Erzincan city, which is mostly located in a deep alluvial basin in nearby area of North Anatolian Fault Zone (NAFZ). The maps for addressing certain physical properties of soils Atterberg’s limits, classification, standard penetration test (SPT), shear wave velocity (Vs), and primary wave velocity (Vp) findings in the region have been prepared using field-based methods and geotechnical data of 92 available boreholes in Erzincan. The geological units underlying the city is consisted of various amounts of silt, clay, gravel, and sand, while it is predominantly classified as either low plastic clay (CL) or medium plastic silt (SM). Liquid limit (LL) and plastic limit (PL) values varied between 28–45% and 5–24%, respectively. The lowest SPT blow counts were found to be in southern part of the Erzincan city. The northern parts with the highest Vs values (higher than 1000 m/s) have been determined as very dense cohesionless soils. Furthermore, a correlation performed via NN between the unconfined compression testing results and dynamic elastic modulus from field studies yielded a very high correlation coefficient (R2=0.97). Evidently, the GIS maps produced by inverse distance weighting (IDW) method could be efficiently used by engineers as well as researchers for the purpose of land-use planning and urban development in earthquake-prone regions.Öğe Comparison of extreme learning machine and deep learning model in the estimation of the fresh properties of hybrid fiber-reinforced SCC(Springer, 2021) Kına, Ceren; Türk, Kazım; Atalay, Esma; Dönmez, İzzeddin; Tanyıldızı, HarunThis paper studied the estimation of fresh properties of hybrid fiber-reinforced self-compacting concrete (HR-SCC) mixtures with different types and combinations of fibers by using two different prediction method named as the methodologies of extreme learning machine and long short-term memory (LSTM). For this purpose, 48 mixtures, which were designed as single, binary, ternary and quaternary fiber-reinforced SCC with macro-steel fiber, two micro-steel fibers having different aspect ratio, polypropylene (PP) and polyvinylalcohol (PVA), were used. Slump flow, t50 and J-ring tests for designed mixtures were conducted to measure the fresh properties of fiber-reinforced SCC mixtures as per EFNARC. The experimental results were analyzed by Anova method. In the devised prediction model, the amounts of cement, fly ash, silica fume, blast furnace slag, limestone powder, aggregate, water, high-range water-reducer admixture (HRWA) and the fiber ratios were selected as inputs, while the slump flow, t50 and the J-ring were selected as outputs. Based on the Anova analysis’ results, the macro-steel fiber was the most important parameter for the results of slump-flow diameter and t50, while the most important parameter for the results of J-ring was fly ash. Furthermore, it was found that the use of more than 0.20% by volume of 6/0.16 micro-steel fiber positively influenced the fresh properties of SCC mixtures with hybrid fiber. On the other hand, the inclusion of steel fiber instead of synthetic fiber into SCC mixture as micro-fiber was more advantageous in terms of workability of mixtures as result of hydrophobic nature of steel fibers. This study found that extreme learning machine model estimated the slump flow, t50 and J-ring with 99.71%, 81% and 94.21% accuracy, respectively, while deep learning model found the same experimental results with 99.18%, 77.4% and 84.8% accuracy, respectively. It can be emphasized from this study that the extreme learning machine model had a better prediction ability than the deep learning model.Öğe Effect of macro and micro fiber volume on the flexural performance of hybrid fiber reinforced SCC(Techno Press, 2020) Türk, Kazım; Kına, Ceren; Öztekin, ErolThe aim of this study is to investigate the flexural performance of hybrid fiber reinforced self-compacting concrete (HFRSCC) having different ratio of micro and macro steel fiber. A total of five mixtures are prepared. In all mixtures, the sum of the steel fiber content is 1% and also water/binder ratio is kept constant. The amount of high range water reducer admixture (HRWRA) is arranged to satisfy the workability criteria of self-compacting concrete. Four-point bending test is carried out to analyze the flexural performance of the mixtures at 28 and 56 curing days. From the obtained load-deflection curves, the load carrying capacity, deflection and toughness values are investigated according to ASTM C1609, ASTM C1018 and JSCE standards. The mixtures containing higher ratio of macro steel fiber exhibit numerous micro-cracks and, thus, deflectionhardening response is observed. The mixture containing 1% micro steel fiber shows worst performance in the view of all flexural parameters. An improvement is observed in the aspect of toughness and load carrying capacity as the macro steel fiber content increases. The test results based on the standards are also compared taking account of abovementioned standards.Öğe Correlatıon between SPT and PMT results for sandy and clayey soils(Eskişehir Teknik Üniversitesi, 2021) Yıldız, ÖzgürDetermination of soil deformation and strength properties is of great importance in geotechnical design. The disturbance that occurred during the sampling from the field affects the results obtained by the laboratory tests. Therefore, the lack of representation of the field conditions and in-situ soil features with laboratory tests leads the designers to carry out field tests. Standard penetration test (SPT) and the Menard pressuremeter test (PMT) are the most widely used geotechnical field tests in which the results are utilized to investigate soil properties and lateral deformation characteristics at a specified depth. In this study, a total of 102 data of sandy and clayey soils belonging to the geotechnical investigations carried out in Istanbul were compiled. The regression analysis between the corrected SPT blow count N60, pressuremeter modulus EPMT, limit pressure PL and EPMT/PL ratio is performed. Empirical equations were separately developed for sandy and clayey soils between the considered parameters. The developed equations showed that there are acceptable relationships between the parameters examined in the particular dataset. Moreover, a neural network (NN) based prediction model was developed to predict EPMT and PL using the available soil data. The highly accurate prediction performance of the proposed model demonstrated the availability of modern methods for the estimation of soil parameters.Öğe Mechanical and microstructural properties of polypropylene fiber-reinforced geopolymer composites(The Society of Fiber Science and Technology, 2019) Maraş, Müslüm Murat; Köse, Mehmet MetinGeopolymers are a kind of polymeric material that can be formed using industrial applications based on inorganic polycondensation. They can be used in applications to replace traditional cement with environmental and technical benefits. In this paper, mixtures with different silica moduli (0.8, 0.9,1.0) and molar ratios (12, 14, 16 M) were used to prepare geopolymer mortar, and the optimum polypropylene (PP) fiber-reinforced mixture was determined. The PP fibers in the geopolymer form constituted 0, 0.5 and 1.0% of the total volume of the mixture. Geopolymer (cement-less) matrix interaction performance played an important role in identifying the characteristics of the fiber-based composites. The mechanical and microstructural properties of the mixtures were determined. The optimum mixture was obtained from the sample with a molar ratio of 16 M and 0.5% fiber. This mixture was then used to cast the fiber-reinforced gepolymer composites. These composites were produced using three different geosynthetics with the optimum mixture. The experimental behavior of the composites was investigated using PP geogrid composite (PPGC), carbon geogrid composite (CGC) and polyfelt geotextile composite (PGC) under flexural loading. We observed that the compressive strength of the composites increased as the curing temperature and NaOH concentration increased in geopolymer composites with a high molar ratio. The microstructural properties of the samples changed with temperature: the voids decreased and the calcium silicate hydrate (CSH) gels provided compact bonding during the geopolymerization process. Furthermore, the PPGC demonstrated high viscosity, good adherence and high flexural strengthÖğe Bond strength of reinforcing bars in hybrid fiber-reinforced SCC with binary, ternary and quaternary blends of steel and PVA fibers(Springer, 2021) Kına, Ceren; Türk, KazımIn this study, the effect of inclusion of single fiber and binary, ternary and quaternary fiber hybridization on the bond performance of high strength self-compacting concrete (SCC) was investigated and 12 beam specimens having lap-spliced reinforcing bars in tension at the mid-span were designed. Four different fibers were used with different hybridizations. Fiber reinforced concrete beams demonstrated higher failure loads with a greater number of cracks. Especially the specimens with ternary fiber hybridization showed the best performance that the ultimate load resistance was 60% higher than that of the specimen without fiber. After splitting failure, the beam specimens with binary hybridization of macro steel fiber and polyvinyl-alcohol (PVA) fiber and also, the specimens with ternary hybridization of macro steel fiber, micro steel fiber with 13 mm in length (OL 13/.16) and PVA fiber showed a gradually drop in performance with increasing deflections. Besides, results indicate that the least improvement in bond strength was observed in the specimen having quaternary fiber hybridization of macro steel fiber, OL 13/.16 and micro steel fiber with 6 mm in length (OL 6/.16) and PVA fiber. The bond strength results were also compared with the ones calculated from the existing prediction equations. It was found that Zuo and Darwin and Esfahani and Rangan equations gave better results than the equations of Orangun et al. and ACI 318 on the hybrid fiber reinforced SCC. Based on the results, it was indicated that in these proposals, a new parameter was necessary for the fiber content so in this study, a new empirical equation was derived by using fiber reinforced index for fiber reinforced SCC. The proposed equation gave better estimation in the specimens with single fiber and binary and ternary fiber hybridization.Öğe Köprülerin yapısal analizinde hareketli yük dağıtma katsayıları etkisinin incelenmesi(Bitlis Eren Üniversitesi, 2020) Ülker Peker, Fatma; İnce, RagıpBu çalışmada AASHTO-LRFD Köprü Şartnamesinde uygulama ve hesap özellikleri verilen hareketli yük dağıtma katsayılarının (LLDF) köprülerin analizinde kullanılması araştırılmıştır. Bu amaçla, üç açıklıklı 30-30-30 m ve 33- 50-38 m köprülerin LLDF hesaplamaları AASHTO Şartnamesine göre yapılmıştır. Bu köprüler yaklaşık analiz yöntemi olan Çizgisel-Kiriş yöntemiyle analiz edilmiştir ve hesaplanan LLDF katsayıları analizde kullanılmıştır. 30-30-30 m köprünün SAP2000 programıyla ve 33-50-38 m köprünün CSiBridge programıyla analizi yapılmıştır. Bu programlarla yapılan analizde LLDF katsayıları program tarafından otomatik olarak hesaplamalara katılmaktadır. Yapılan çalışma sonucunda Çizgisel-Kiriş yöntemiyle analizden elde edilen sonuçların, hassas ve kesin analiz yapan SAP2000 ve CSiBridge programlarıyla elde edilen sonuçlara çok yakın olduğu görülmüştür. Böylece, AASHTO Tasarım Şartnamesi’ne göre LLDF hesaplamalarının yapısal analizde kullanımının doğruluğu ve uygunluğu ortaya konulmuştur.
