Civil Engineering / İnşaat Mühendisliği
Permanent URI for this collectionhttps://hdl.handle.net/11147/13
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Article Citation - WoS: 7Citation - Scopus: 8Enrichment of Trace Element Concentrations in Coal and Its Combustion Residues and Their Potential Environmental and Human Health Impact: Can Coal Basin, Nw Turkey as a Case Study(Inderscience Enterprises, 2016) Baba, Alper; Gürdal, Gülbin; Şanlıyüksel Yücel, DenizIn this study, the variation of trace element concentrations ( total of 48 trace elements including rare earth elements) in coal, coal ash and fly ash were examined and compared with coal Clarke values. Results showed that the average concentrations of trace elements including As, B, Cu, Ce, Co, Cs, Gd, Hf, La, Lu, Mo, Nd, Nb, Pr, Pb, Sc, Sm, Ta, Tb, Th, U, V, W, Y, Yb, Zn and Zr in the Can Basin coals are higher than their respective Clarke values for world low-rank coals. The elements As, Cu, Co, Cs, Mo, Nb, Sc, Pb, Pr, Th, U, V, Zn and Zr are enriched in coal ashes, whereas As, Co, Nb, Sc, U and V are enriched in fly ashes. Among the elements, maximum enrichment in coal was observed for As, with the average concentration of 253.5 ppm As in the Can Basin coals, while the coal Clarke value is 14 ppm and world average value is 8.3 ppm. From the ecotoxicological point of view, combustion residues formed by indoor combustion of coal and/or in thermal power plants may be a hazard to the environment and to aquatic and terrestrial life including human beings, particularly As, trace elements and released radioactive elements.Article The Relation of Geogenic and Antrophogenic Factors With Blood and Hair Lead and Arsenic Levels in Women Living in Çan and Bayramiç Districts of Çanakkale Province(Nobelmedicus, 2019) Baba, Alper; Gündüz, Orhan; Bakar, Çoşkun; Sülün, Serdar; Save, DilşadObjective: Mining areas and associated industrial activities carry considerable risks for human health due to multi-pathway exposure of heavy metals such as arsenic and lead. The objective of this study was to compare arsenic and lead levels in human blood and hair samples in an industrial mining area in northwestern Turkey with that of a non-exposed group demonstrating similar sociocultural characteristics. Material and Method: The population of the study consisted of 674 nonsmoker women over the age of 40 who were selected on a random basis from mine region and control area. Venous blood samples were taken and analyzed for blood lead and arsenic levels in all participants. Hair samples were later collected from 108 women with high levels in blood samples. Results: The results showed that the highest prevalence of occurrences was found in district centers whereas relatively lower values were observed in the villages. Hair arsenic and lead levels were comparably higher in the industrialized area (Çan Region) where low-quality coal combustion used in power generation and residential heating were dominant. Conclusion: Although high correlations were not found, blood and hair arsenic and lead levels in individuals living in industrial and agricultural areas were found to be high at levels influencing the human health. On the other hand, these results should be further supported and verified with advanced and long duration monitoring activities.Article Citation - WoS: 11Citation - Scopus: 12Cement Based Strain Sensor: a Step To Smart Concrete(Foundation Cement, Lime, Concrete, 2011) Teomete, Egemen; Erdem, Tahir KemalAccording to a report published in USA, 30% of the bridges in USA were found to be structurally de cient while concrete infrastructures have a state of material deterioration before the design life is reached (1). Earthquakes, material degradations and other environmental effects decrease the performance of the structures. The assessment of structures by structural health monitoring is very important to protect the lives of people. The best decision about a damaged structure after an earthquake can be made by use of structural tests and structural health monitoring. Structural tests and structural health monitoring are important steps in the decision making of asset management for maintenance and repair of infrastructures. The classical sensors (strain gauges, piezo-electric sensors) have low durability, low sensitivity and high cost. The low durability of classical sensors disables long term measurement while their high cost limits the amount of sensors that can be used (2). The addition of carbon ber to cement based material decreases the electrical resistance of the material. By application of load, the electrical resistance of the material changes (3-5).Article Citation - WoS: 5Citation - Scopus: 7Experimental and Modeling Study of Strength of High Strength Concrete Containing Binary and Ternary Binders(Foundation Cement, Lime, Concrete, 2011) Erdem, Tahir Kemal; Tayfur, Gökmen; Kırca, ÖnderSilica fume (SF), fl y ash (FA) and ground granulated blastfurnace slag (S) are among the most widely utilized mineral additions for normal strength concrete (NSC) and high strength concrete (HSC). High Reactivity Metakaolin (HRMK) is a relatively new mineral addition, produced by calcination of highly pure kaolin. The replacement of cement with HRMK increases the strength, especially at early ages, and improves durability of concrete. (1-3). Pumice (P) is a porous volcanic glass containing 60-75 SiO2% and 13-17% Al2O3. When fi nely ground, it shows pozzolanic characteristics but it is generally used as a lightweight aggregate in the concrete industry (4, 5). HRMK and P have white color and, therefore, are useful for production of white concrete when applied with white Portland cement (WPC)Article Citation - WoS: 1Citation - Scopus: 1Estimation of Mechanical Properties of Limestone Using Regression Analyses and Ann(Foundation Cement, Lime, Concrete, 2012) Teomete, Egemen; Tayfur, Gökmen; Aktaş, EnginEstimation of mechanical properties of rocks is important for researchers and field engineers working in cement and concrete industry. Limestone is used in cement production. In this study, Schmidt hammer, ultrasonic pulse velocity, porosity, uniaxial compression and indirect tension tests were conducted on limestone obtained from a historical structure. Regression analyses were used to develop models relating mechanical properties of limestone. Artificial Neural Network (ANN) was performed to determine the mechanical properties. The performance of regression models and ANN were compared by existing models in the literature. The results showed that the regression models and ANN yield satisfactory performance with minimum error. The regression models between tensile strength and wave velocity, tensile strength and porosity, wave velocity and porosity have been developed for the first time in literature. The ANN is used for the first time to estimate the mechanical properties of limestone. The use of separate training and testing sets in the regression analyses of mechanical properties of limestone is conducted for the first time. The models developed in this study can be used by researchers and field engineers to relate the mechanical properties of limestone.Article Citation - WoS: 2Citation - Scopus: 1Significance of Rent Attributes in Prediction of Earthquake Damage in Adapazari, Turkey(Czech Technical University in Prague, 2014) Tayfur, Gökmen; Bektaş, Birkan; Duvarcı, YavuzThis paper analyses rent-based determinants of earthquake damage from an urban planning perspective with the data gathered from Adapazari, Turkey, after the disaster in 1999 Eastern Marmara Earthquake (EME). The study employs linear regression, log-linear regression, and artificial neural networks (ANN) methods for cross-verification of results and for finding out the significant urban rent attribute(s) responsible for the damage. All models used are equally capable of predicting the earthquake damage and converge to similar results even if the data are limited. Of the rent variables, the physical density is proved to be especially significant in predicting earthquake damage, while the land value contributes to building resistance. Thus, urban rent can be the primary tool for planners to help reduce the fatalities in preventive planning studies.