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Öğe Adsorption of Methylene Blue using Bottom Ash: Experimental Design, Isotherm Analysis, and Optimum Conditions(Global Network Environmental Science & Technology, 2024) Cifci, Deniz Izlen; Cihan, Mehmet Timur; Gunes, Elcin; Ozturk, Tuba; Gunes, YalcinThis study investigated the removal of methylene blue (MB) via adsorption using waste bottom ash. The bottom ash, sourced from a waste storage site in the & Ccedil;orlu district of Tekirda & gbreve; province, Thrace Region, was utilized as the adsorbent. The research examined the impact of several variables on MB removal, including bottom ash dosage, pH, contact time, and agitation speed. It was found that all parameters had a single-variable effect, while pH exhibited a quadratic effect on MB removal in a model- based analysis. The optimization of the model for maximum MB removal identified the optimal conditions as 0.978 g bottom ash dosage, pH 3, 15 minutes of adsorption time, and 50 rpm agitation speed. Under these conditions, the model predicted an MB removal efficiency of 71%, which was experimentally confirmed to be 72.5%. The adsorption process was found to fit with the Freundlich isotherm, indicating a multilayer adsorption mechanism on the heterogeneous surface of the adsorbent. This research not only highlights the feasibility of using bottom ash from coal combustion as an economical adsorbent for dye-contaminated wastewater but also underscores its potential to inform and inspire future studies on waste recycling and wastewater treatment.Öğe Application of AI models for predicting properties of mortars incorporating waste powders under Freeze-Thaw condition(Techno-Press, 2022) Cihan, Mehmet Timur; Aral, İbrahim FedaThe usability of waste materials as raw materials is necessary for sustainable production. This study investigates the effects of different powder materials used to replace cement (0%, 5% and 10%) and standard sand (0%, 20% and 30%) (basalt, limestone, and dolomite) on the compressive strength (fc), flexural strength (fr), and ultrasonic pulse velocity (UPV) of mortars exposed to freeze-thaw cycles (56, 86, 126, 186 and 226 cycles). Furthermore, the usability of artificial intelligence models is compared, and the prediction accuracy of the outputs is examined according to the inputs (powder type, replacement ratio, and the number of cycles). The results show that the variability of the outputs was significantly high under the freeze-thaw effect in mortars produced with waste powder instead of those produced with cement and with standard sand. The highest prediction accuracy for all outputs was obtained using the adaptive-network-based fuzzy inference system model. The significantly high prediction accuracy was obtained for the UPV, fc, and fr of mortars produced using waste powders instead of standard sand (R2 of UPV, fc and ff is 0.931, 0.759 and 0.825 respectively), when under the freeze-thaw effect. However, for the mortars produced using waste powders instead of cement, the prediction accuracy of UPV was significantly high (R2=0.889) but the prediction accuracy of fc and fr was low (R2fc=0.612 and R2ff=0.334). Copyright © 2022 Techno-Press, Ltd.Öğe Application of Al models for predicting properties of mortars incorporating waste powders under Freeze-Thaw condition(Techno-Press, 2022) Cihan, Mehmet Timur; Aral, İbrahim FedaThe usability of waste materials as raw materials is necessary for sustainable production. This study investigates the effects of different powder materials used to replace cement (0%, 5% and 10%) and standard sand (0%, 20% and 30%) (basalt, limestone, and dolomite) on the compressive strength (f(c)), flexural strength (f(r)), and ultrasonic pulse velocity (UPV) of mortars exposed to freeze-thaw cycles (56, 86, 126, 186 and 226 cycles). Furthermore, the usability of artificial intelligence models is compared, and the prediction accuracy of the outputs is examined according to the inputs (powder type, replacement ratio, and the number of cycles). The results show that the variability of the outputs was significantly high under the freeze-thaw effect in mortars produced with waste powder instead of those produced with cement and with standard sand. The highest prediction accuracy for all outputs was obtained using the adaptive-network-based fuzzy inference system model. The significantly high prediction accuracy was obtained for the UPV, f(c), and f(r) of mortars produced using waste powders instead of standard sand (R-2 of UPV, f(c )and f(r) is 0.931, 0.759 and 0.825 respectively), when under the freeze-thaw effect. However, for the mortars produced using waste powders instead of cement, the prediction accuracy of UPV was significantly high (R-2=0.889) but the prediction accuracy of f(c) and f(r) was low (R(2)f(c)=0.612 and R(2)f(r)=0.334).Öğe Atıksulardan Koi ve Renk Giderimi: Fenton Prosesinin Optimizasyonu(2015) Güneş, Elçin; Cihan, Mehmet TimurBu çalışmada, atıksulardan Fenton prosesi ile KOİ ve renk giderimi için gerekli şartların optimizasyonu sağlanmaya çalışılmıştır. Çalışmada, tepki değişkenleri Y1 ve Y2 sırasıyla KOİ giderim verimi (%) ve renk giderim verimi (%), etki değişkenleri A, B ve C sırasıyla H2O2 miktarı (mmol/L), reaksiyon süresi (sa) ve H2O2/Fe2+ oranı olarak seçilmiştir. Deneysel tasarım olarak iki düzeyli faktöriyel tasarım kullanılmıştır. Köşe noktalarda 23=8, merkez noktasında 3 ve toplamda 3.(8+3)=33 deneme noktasında ölçüm gerçekleştirilmiştir. H2O2 miktarı (mmol/L), reaksiyon süresi (saat) ve H2O2/Fe2+ oranı olmak üzere üç değişkenin KOİ giderim ve renk giderim verimlerine etkisi araştırılmıştır. KOİ giderme verimi ve renk giderme verimi birlikte dikkate alındığında optimum şartlar H2O2 konsantrasyonu 8 mmol/L, temas süresi 3 sa ve HO2/Fe2+ oranı 2.6 olarak seçilmiştir. Bu şartlarda en yüksek KOİ giderim verimi ve renk giderim verimi sırasıyla %82 ve %93 olarak bulunmuştur.Öğe Bazalt tozu katkılı harçların mekanik ve geçirimlilik özeliklerinin araştırılması(2019) Akyüncü, Veysel; Cihan, Mehmet TimurBazalt beton üretiminde agrega olarak tercih edilen ancak üretimi esnasında yan ürünolarak yüksek miktarda atık bazalt tozu malzemesi ortaya çıkaran bir kayaçtır. Bu atıkmalzemenin geri dönüşümüyle çevreye ve insan sağlığına verdiği zararın azaltılmasınınyanında çimentoyla ikame edilmesi harç (beton) hammadde maliyetinde bir miktardüşme sağlayacaktır. Çalışma kapsamında kontrol serisi ve %5, %10, %15, %20oranlarında bazalt tozu çimento ile ikame edilerek toplamda 5 seri harç numuneüretilerek taze ve sertleşmiş harç deneyleri gerçekleştirildi. Taze harç deneyi olarakkıvam tayini, sertleşmiş harç deneyi olarak basınç, eğilme, yarmada çekme vegeçirimlilik deneyi olarak basınç altında su işleme derinliği deneyleri yapıldı. %10ikameli seride basınç dayanımında yaklaşık olarak %8 oranında artış elde edilirken,eğilme dayanımında ise %15 ikameli seride önemli bir artış elde edildi. %10 bazalt tozuikame oranına sahip seride basınç altında su işleme derinliği düşüş göstererek olumlubir katkı sağlamaktadır.Öğe Cam Lifi Uzunluğu ve Oranının Çimento Harçlarının Mekanik Özelliklerine Etkisi(Kırıkkale Üniversitesi, 2022) Toklu, Kenan; Avşar, Yunus Emre; Cihan, Mehmet Timur; Bıçakcı, EnginBetonun mühendislik özelliklerinde iyileştirmeler yapabilmek için farklı lif türleri beton üretiminde kullanılmaktadır. Fakat lif türü, narinlik gibi değişkenler üretilecek olan betonun özellikleri üzerinde farklı etkilere sahiptir. Bu çalışma kapsamında, farklı uzunluklardaki (3 mm, 6 mm ve 12 mm) cam lifleri, karışıma hacimce % 0.3, % 0.4 ve % 0.5 oranlarında ilave edilerek üretilen harçların yayılma değeri, basınç dayanımı, eğilmede çekme dayanımı ve ultrasonik atımlı dalga hızı incelendi. Elde edilen sonuçlara göre, karışım içerisindeki cam lif miktarının artmasıyla genel olarak karışımın yayılma değerinde, basınç dayanımı ve ultrasonik atımlı dalga hızında azalmalar meydana gelirken, eğilmede çekme dayanımında ise iyileşmeler meydana geldiği görülmüştür.Öğe Cod and Color Removal From Wastewaters: Optimization of Fenton Process(Pamukkale Univ, 2015) Güneş, Elçin; Cihan, Mehmet TimurIn this study, COD and color removal from wastewaters by Fenton's oxidation were investigated. In the study the response variables of Y-1 and Y-2 were selected as COD removal rate (%) and color removal rate(%), and efficacy variables of A, B, anc C were selected as H2O2 concentration (mmol/L), reaction time (h) and H2O2/Fe2+. The experimental design was used as a two-level factorial design. In the corner points 2(3) = 8, in the center points 3 and a total of 3.(8+3)=33 experiments were conducted. Effect of H2O2 concentration (mmol/L), reaction time (h) and H2O2/Fe2+ molar ratio on COD removal rate and color removal rate were investigated. The optimum conditions for maximum COD removal rate and color removal rate were at H2O2 concentration 8 mmol/L, reaction time 3 h and H2O2/Fe2+ molar ratio 2.6. At optimum conditions 82% COD removal rate and 93% color removal rate were achieved.Öğe Comparison of artificial intelligence methods for predicting compressive strength of concrete(Croatian Soc Civil Engineers-Hsgi, 2021) Cihan, Mehmet TimurCompressive strength of concrete is an important parameter in concrete design. Accurate prediction of compressive strength of concrete can lower costs and save time. Therefore, thecompressive strength of concrete prediction performance of artificial intelligence methods (adaptive neuro fuzzy inference system, random forest, linear regression, classification and regression tree, support vector regression, k-nearest neighbour and extreme learning machine) are compared in this study using six different multinational datasets. The performance of these methods is evaluated using the correlation coefficient, root mean square error, mean absolute error, and mean absolute percentage error criteria. Comparative results show that the adaptive neuro fuzzy inference system (ANFIS) is more successful in all datasets.Öğe EFFECT LEVELS OF REPLACEMENT RATIO AND SPECIMEN AGE ON THE MECHANICAL PROPERTIES OF MORTARS CONTAINING WASTE BOTTOM ASH(Gheorghe Asachi Technical University of Iasi, Romania, 2024) Günay, Gülbahar; Cihan, Mehmet Timur; Güneş, ElçinThe coarse solid residue formed at the bottom of combustion boilers is called waste bottom ash (WBA). The most important difficulties that can arise when storing WBA are the potential for leaching of hazardous substances and the high space requirement. For these reasons, there is an urgent need to investigate alternative materials capable of substituting for sand, a natural mineral extensively used in concrete and mortar production. This study aimed to evaluate the feasibility of changing the amount of WBA in concrete and mortar formulations in order to reduce sand consumption in the construction industry and transform WBA into a valuable economic resource for the sector. For this purpose, bottom ash was taken from a landfill in Thrace, an industrially dense region. Effects of the variables of the replacement ratio (B) of WBA in mortar mixtures and the sample age (A) of the formed mortar on the ultrasonic pulse velocity (V), flexural strength (ff), and compressive strength (fc) of mortar were determined using analysis of variance (ANOVA), and models were created for V, ff, and fc. Notably, there was no decrease in the fc value at 25% B, while an increase in the fc value was achieved at 15% B. The R2 values for the models were 0.99, 0.92, and 0.95 for V, ff, and fc, respectively. The study concludes that WBA can effectively serve as a substitute for standard sand in mortar mixtures at specific ratios. © 2024 Gheorghe Asachi Technical University of Iasi, Romania. All rights reserved.Öğe Erratum: Prediction of Concrete Compressive Strength and Slump by Machine Learning Methods (Advances in Civil Engineering (2019) 2019 (3069046) DOI: 10.1155/2019/3069046)(Hindawi Limited, 2020) Cihan, Mehmet TimurIn the article titled “Prediction of Concrete Compressive Strength and Slump by Machine Learning Methods” [1], there was an error in equation (1), which should be corrected as follows: (Formula Presented). Copyright © 2020 M. Timur Cihan.Öğe Evaluation of mechanical properties and leaching tests results of mortars containing waste bottom ash as replacement of cement(Springer, 2024) Guenay, Guelbahar; Cihan, Mehmet Timur; Guenes, ElcinThe disposal of waste bottom ash (WBA) is an environmental and economic challenge for the manufacturer. Therefore, disposal of waste bottom ashes is important for sustainable production. In this study, the usability of WBA instead of cement in the mortar was investigated. For this purpose, the workability, ultrasonic pulse velocity (UPV), flexural strength (ff), compressive strength (fc), microstructure, and hazard potentials of mortars containing WBA were examined. Effect levels of the selected variables (replacement ratio: 0%, 5%, 10%, 15%, 25%, 35%, and 50%, specimen age: 28, 60, and 90 day) on the UPV, ff, and fc were determined by ANOVA, and response surfaces were created. UPV and fc were decreased at all specimen ages with an increasing replacement ratio. The R2 of the models for the UPV, ff, and fc is higher (0.9660, 0.8034, and 0.9029). According to the leaching test results, Cd, Pb, Hg, and As values of all mortar samples were below the detection limit (not detectable) in this evaluation. The Cr values in all mortar samples remained below the maximum concentration of 5 mg/L, which is the given restriction of TCLP procedure.Öğe Experimental analysis of the thermal behaviour of mezzanine floors in buildings with cavity wall insulation(Academic Journals, 2010) Şenkal Sezer, Filiz; Cihan, Mehmet Timur; Dilmaç, ŞükranIn this study, the thermal behaviour of mezzanine beam-slab floor sections of buildings under temperate climate conditions was experimentally investigated. Data were obtained from measurements on buildings under service conditions. Heat flow density and temperatures around the thermal bridges formed by the beam and floor elements were calculated. Thermal behaviours of mezzanine floor sections made of insulated cavity wall and beam was studied. The outcome measures were the general behaviour of components within the total measurement time of about one month; differences between wall and beam temperatures in all measurements; variation of section temperatures; variation of minimum, maximum and average temperatures measured in the environment and the surfaces; heat flow through the external surface of the beam; and damping ratios.Öğe Experımental analysıs of the thermal behavıour of mezzanıne floors ın buıldıngs wıth cavıty wall ınsulatıon(Academic Journals, 2010) Şenkal Sezer, Filiz; Cihan, Mehmet Timur; Dilmaç, ŞükranIn this study, the thermal behaviour of mezzanine beam-slab floor sections of buildings under temperate climate conditions was experimentally investigated. Data were obtained from measurements on buildings under service conditions. Heat flow density and temperatures around the thermal bridges formed by the beam and floor elements were calculated. Thermal behaviours of mezzanine floor sections made of insulated cavity wall and beam was studied. The outcome measures were the general behaviour of components within the total measurement time of about one month; differences between wall and beam temperatures in all measurements; variation of section temperatures; variation of minimum, maximum and average temperatures measured in the environment and the surfaces; heat flow through the external surface of the beam; and damping ratios. © 2010 Academic Journals.Öğe Investigation of Properties of Mortars Containing Waste Stone Powder Instead of Sand under Freezing-Thawing Effect(Institute of Physics Publishing, 2019) Aral, İbrahim Feda; Cihan, Mehmet TimurNowadays, sustainable production is vitally important in consideration of limited raw materials and an environmental welfare. Sustainable production encourages the use of several industrial wastes as raw materials in different fields. Water and aggregate are among the most consumed items on the earth. Waste powders, with a size of 75 ?m or less, formed during the aggregate production process affect both the environment and human health negatively. For sustainable aggregate production, it is important that the waste powder generated during the aggregate production phase is used in the concrete industry. Limestone, basalt and dolomite are commonly used as concrete aggregate. In this study, limestone, basalt and dolomite waste powders were replaced with fine aggregate (sand). Reference samples (0 %) and 20%-30% waste stone powder produced by replacing standard sand with mortar. The freeze-thaw effect (40 cycles) on compressive strength, flexural strength, ultrasonic pulse velocity, weight loss are analysed. For this purpose, a total of 105 (21-5) 40-40-160 mm prism samples were produced. Under the influence of freeze-thaw cycles, the loss of weight in samples produced by replacement of standard sand and waste stone powders is less than that of the reference samples. The ultrasonic pulse velocity tend to increase in general as the number of freeze-thaw cycles increases. The flexural strength rises as the replacement rate is increased, and after the freeze-thaw cycle, a slight decline is observed. The compressive strength values decrease as the replacement rate is increased. It decreases at the end of the 10th freeze-thaw cycle but the variability tend decrease at extending cycles (20-40). © Published under licence by IOP Publishing Ltd.Öğe ISO 9164 heat loss in roof-wall sections(Academic Journals, 2011) Güner, A.; Dilmaç, S.; Cihan, Mehmet TimurIn the simple ISO 9164 calculation procedure for transmission heat loss coefficient, HT, it is unclear, and undefined for floor or roof-wall sections, how the parameters in the equations will be calculated. In this paper, a method is proposed for the calculation of ISO 9164 parameters for roof-wall sections. The results obtained by the proposed method for typical roof sections are compared with those obtained by the EN 832/EN 13789/EN ISO 14683 methods and with the L2D values from 2D analysis. A comparison of the floor and roof behaviour is realized using the results of the present and the previous works of the authors. The HT values obtained by the proposed model using the sum of qy through the beam are harmonised with the L2D for floors, which are significantly different from the L2D for roofs with parapet. The results indicate that the L2D values cited in EN 10211-1 are sensitive to the 2D heat flows for floor sections. However, the L2D is not sufficiently sensitive to heat flow from the beam to the parapet and the interactions between the zones within the beam section, whereas the proposed method is more sensitive to the 2D heat flows. © 2011 Academic Journals.Öğe MECHANICAL PROPERTIES OF MORTARS CONTAINING PARTIALLY WOOD BOTTOM ASH INSTEAD OF CEMENT(2022) Cihan, Mehmet Timur; Avşar, Yunus EmreCarbon dioxide (CO2) released into the atmosphere during the production of Portland cement (PC) is one of the important factors causing global warming. Therefore, studies are carried out on different materials to reduce PC consumption. The effect levels of the wood bottom ash (WBA) ratio and specimen age on the response variables (compressive strength, flexural strength, and ultrasonic pulse velocity) were investigated in this study. Mortar specimens were produced using PC, WBA, CEN standard sand, and distilled water. The produced specimens were cured in water until the test day. WBA ratios are 0%, 5%, 10%, 20%, 35% and 50% by weight of binder. As a result, it was determined that the optimum WBA ratio was 5%. In addition, R2 values of response variables were found to be high (ultrasonic pulsed wave velocity; 0.8925, flexural strength; 0.9356, compressive strength; 0.9404) by analysis of variance (ANOVA). This shows that the models have a high correlation. Moreover, the terms added to the models have a significant effect on the responses.Öğe MECHANICAL PROPERTIES OF MORTARS CONTAINING WOOD BOTTOM ASH INSTEAD OF CEMENT(2022) Cihan, Mehmet Timur; Avşar, Yunus EmreCarbon dioxide (CO2) released into the atmosphere during the production of Portland cement (PC) is one of the important factors causing global warming. Therefore, studies are carried out on different materials to reduce PC consumption. The effect levels of the wood bottom ash (WBA) ratio and specimen age on the response variables (compressive strength, flexural strength, and ultrasonic pulse velocity) were investigated in this study. Mortar specimens were produced using PC, WBA, CEN standard sand, and distilled water. The produced specimens were cured in water until the test day. WBA ratios are 0%, 5%, 10%, 20%, 35% and 50% by weight of binder. As a result, it was determined that the optimum WBA ratio was 5%. In addition, R2 values of response variables were found to be high (ultrasonic pulsed wave velocity; 0.8925, flexural strength; 0.9356, compressive strength; 0.9404) by analysis of variance (ANOVA). This shows that the models have a high correlation. Moreover, the terms added to the models have a significant effect on the responses.Öğe Mechanical properties of mortars with EarthZyme additive(Croatian Soc Civil Engineers-Hsgi, 2023) Cihan, Mehmet Timur; Yardimli, Seyhan; Ozsahin, Burak; Mihlayanlar, EsmaConcrete is the most widely used building material in the world. However, owing to the high CO2 emissions from the production of cement, its use has been questioned, and attempts have been made to improve it. Various chemical additives are being used to improve concrete properties. Enzymes are organic materials and have been especially favoured in recent years owing to their low costs when used in traditional soil stabilisation methods. This study used the 'EarthZyme' enzyme as a plaster mortar additive and investigated its effects on the mechanical properties of mortars. EarthZyme completely biodegrades in nature and is used for soil stabilisation. By producing mortar specimens with additive enzyme ratios of 0 %, 0.01 %, 0.02 %, 0.03 %, and 0.04 %, the effects of the enzyme additions on the mechanical properties of the mortars (ultrasonic pulse velocity UPV, flexural strength ff and compressive strength fc) were determined. The flow table values of the mortar specimens in the flow table test varied within the range of 15-17 cm. According to the results, the flow table values of the mortars increase with an increasing addition rate of EarthZyme. Although the additive ratio of the EarthZyme does not significantly affect the mechanical properties of mortars at early ages (3 days), the enzyme addition ratio reduces the UPV and fc while improving ff at late ages (28 days). The enzyme addition ratio has no significant effect on the UPV and ff but has a significant effect on fc.Öğe Multi-response Optimization of Mechanical Properties of Alkali-Activated Mortars(Springer Heidelberg, 2023) Avsar, Yunus Emre; Cihan, Mehmet TimurNowadays, due to energy consumption and adverse environmental effects, it is becoming increasingly important to use different materials to reduce cement consumption. For this purpose, using alkali-activated materials (AAM) in the construction industry is becoming widespread. Due to the complex structure of AAMs, it is necessary to determine the optimum values of the variables that affect the desired mechanical properties. Therefore, multi-response optimization of the mechanical properties of alkali-activated mortars was performed in the study. Cementitious materials (fly ash and blast furnace slag), activators (sodium hydroxide (NaOH) and sodium metasilicate (Na2SiO3)), standard sand, and distilled water were used for the production of mortars. The effect levels of the effect variables (Na2SiO3 solution/NaOH solution ratio-by weight, A; total alkali solution/binder ratio-by weight, B; molarity of NaOH solution, C; Na2SiO3 solution water/Na2SiO3 solution ratio-by weight, D) on the response variables (ultrasonic pulse velocity, UPV; flexural strength, f(f); Compressive strength, f(c)) were determined by analysis of variance (ANOVA) using a rotatable central composite design. The B and D terms have a significant effect on UPV and f(c). The run point, which provides optimum mechanical properties at the selected variation ranges, was obtained using desirability functions (A: 1.88; B: 0.4; C: 11.5; D: 60; UPV: 4.18; f(f): 6.6; f(c): 45.3). The combined desirability value of the optimum run point is 0.81. This value shows that the desired target values are achieved due to multi-response optimization of the mechanical properties.Öğe Predictability of the Mechanical Properties of Glass Fibrous Mortar(Springer Heidelberg, 2022) Cihan, Mehmet Timur; Avşar, Yunus EmreThe features expected from traditional building materials in the construction industry vary, as the needs become too complex. For this reason, fibers are used in the production of concrete or mortar. However, the predictability of the properties of the mortar or concrete-which becomes more complicated with the addition of fibers-decreases. Therefore, one factor at a time experimental designs is insufficient. In this study, 3 mm in length and (12-13) mu m in diameter glass fiber reinforced mortar samples were produced for the determination of the effect levels of the effect variables (fiber ratio, 0.15%, 0.30%, 0.45%, 0.60%, and 0.90% by weight of the mixture; fast mixing time, 60 s, 75 s, and 90 s) on the response variables (flexural strength, compressive strength). As a result of the study, with the analysis of variance (ANOVA), models with high prediction accuracy (flexural strength, R-2 = 0.9194 and compressive strength, R-2 = 0.8193) were obtained. The interaction and higher-order terms (p-value < 0.0001) have a high effect level on the flexural strength than the main terms (p(A)-value = 0.0218, p(B)-value = 0.0273). The effect level of the main terms (p(A)-value = 0.0004 and p(B)-value < 0.0001) on compressive strength is quite high. However, the results show that the interaction and higher-order terms have a high effect level on the response variable. Therefore, experimental designs that take into account multiple effect variables for the predictability of properties of fiber-reinforced mortars should be considered.
