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Bu çalışmada; Türkiye'de kırsal alanlarda ısınma amaçlı olarak kullanılan yenilenebilir enerji kaynaklarından güneşte kurutulmuş sığır gübresi külünün (SGK) farklı oranlarda çimento yerine kullanılmasının, hafif betonun basınç dayanımı üzerine etkisinin araştırılması amaçlanmıştır. Araştırmada, hafif agrega olarak pomza bağlayıcı olarak da CEM I 42,5 R tipi çimento ve SGK ikamesi kullanılmıştır. Karışımlara çimento yerine ağırlıkça belirli oranlarda (%0, %5, %10, %15 ve %20) SGK ikame edilerek 5 grup halinde toplam 45 adet 150×150×150 mm’lik küp numune üretilmiştir. Taze beton deneyleri olarak-birim ağırlık deneyleri; serleşmiş beton deneyleri olarak da kuru birim ağırlık, su emme ve basınç dayanımı deneyleri yapılmıştır. SGK kullanılan numunelerde, SGK ikamesinin artması ile kontrol örneklerine göre su emme miktarında bir miktar artış, basınç dayanımlarında ise bir miktar düşüş görülmüştür. %5, %10, %15 ve %20 oranlarında SGK ikamesi ile üretilen numunelerin 28 günlük basınç dayanımı düşüş değerleri kontrol örnekleri ile karşılaştırıldığında sırasıyla %4, %4,6, %5,5 ve %6 olarak belirlenmiştir. Çimento yerine %20 SGK ikamesinin uygulanması, numunelerin 28 günlük basınç dayanımlarında %6’lık bir azalma gözlemlenmiştir.

Copyright of International Journal of Advances in Engineering & Pure Sciences is the property of Marmara University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Beykent Üniversitesi Fen ve Mühendislik Bilimleri Dergisi is the property of Beykent Universitesi Fen Bilimleri Enstitusu and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fibers are generally added to mixtures to improve the mechanical properties of cementitious systems and to provide ductility. Natural fibers are preferred due to their lower production cost, lower carbon emission and fossil fuel consumption, biodegradability, lower density and ease of manufacturing, and less environmental impact. On the other hand, graphene-derived materials have been proven to have an improving effect on fiber-matrix mechanical and interface properties. Within the scope of this study, the effects of jute fibers subjected to surface improvement with graphene-oxide (GO) on the workability of mortar mixtures, compressive strength, flexural strength, water absorption and drying-shrinkage performances were investigated. Within the scope of the experimental study, in addition to the control mixture without fibers, GO coated and uncoated jute fibers with lengths of 0.5 and 1 cm were added to the mixture at 0.1, 0.3 and 0.5% of the total volume to prepare different fiber mortar mixtures. According to the experimental results, the need for water-reducing admixture increased in mixtures containing fibers. Adding 0.5 cm and 0.1% fiber to the mixtures increased the compressive and flexural strengths. GO coating provided a slight increase in strength compared to uncoated fibers. Water absorption ratios were inversely proportional to compressive strength. Adding fibers reduced the drying-shrinkage amounts. GO-coated fibers were more effective in this case. However, GO-coated fiber contents greater than 0.1% caused an increase in drying-shrinkage. [ABSTRACT FROM AUTHOR]

Copyright of Dicle University Journal of Engineering / Dicle Üniversitesi Mühendislik Dergisi is the property of Dicle Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of SDU Journal of Engineering Sciences & Design / Mühendislik Bilimleri ve Tasarım Dergisi is the property of Journal of Engineering Sciences & Design and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study was performed in order to examine the behavior of natural perlite aggregate composites against durability problems caused by alkali silica reaction (ASR). Mortars containing 5%, 10%, 25%, 50%, 75% and 100% natural perlite were subjected to the ASR test. Mechanical tests were also performed on mortar samples. In addition, scanning electron microscope (SEM) analyzes were also applied. The expansion value of the 25% natural perlite substituted mortar with the highest ASR expansion increased by 145% as compared with the control mortar. When the natural perlite ratio increased from 25% to 100%, the expansion values decreased dramatically. 5% natural perlite substituted mortar had the highest compressive and flexural strengths. The SEM analysis results were obtained to be consistent with the ASR expansion results. Experimental results proved that mortars produced from 100% natural perlite can be used effectively to reduce the durability problems caused by ASR. [ABSTRACT FROM AUTHOR]

Enhancing both the dynamic damping and static strength of ordinary Portland cement (OPC) concrete simultaneously is a significant challenge. Geopolymer concrete (GPC), particularly fly ash-based GPC, offers a promising alternative. This study explores the relationship between damping and strength in heat-cured, low-calcium fly ash-based GPC using sodium silicate (SS) and sodium hydroxide (SH) activators. The findings reveal that SS activators demonstrate stronger positive correlations between damping and strength compared to SH activators. Microstructural analysis indicated that increasing SS dosage from 55 kg/m² to 98 kg/m² resulted in a 17% increase in dynamic damping ratios and a 39% increase in static compressive strength. These results highlight the potential of GPC to surpass OPC concrete in applications requiring both enhanced damping and strength, offering a dual benefit not typically achievable with OPC. The study contributes to a deeper understanding of GPC's capabilities, paving the way for its broader adoption in construction projects. [ABSTRACT FROM AUTHOR]

A branch of artificial intelligence called machine learning is well-positioned as a prediction method that can take into consideration several influencing factors and complex inter-factor connections. Without being specifically trained to do so, these machine learning models have the ability to generalize, predict, and learn from data. Regression theory is a key topic in statistical modelling and machine learning. The main goal of this study is to compare the performance of several popular machine learning regression models for predicting the early-age compressive strength of concretes made from recycled concrete aggregates from a structure that demolished following the Sivrice-Elazig earthquake on January 24, 2020. Early-age concrete compressive strength is even more crucial due to factors like the fact that there are thousands of newly built structures in the aftermath of the earthquake, the quick manufacturing of these structures, and the completion of the project in the lowest amount of time. Determining the early-age concrete strength with high accuracy and in a useful manner is crucial for this reason. Seven different classical machine learning algorithms were employed in this study to achieve all of these goals. Early-age concrete compressive strength values were considered for 1 and 3 days. The relationship between the experimental results and the predicted outcomes of the employed algorithms was investigated, and a thorough comparison of these intelligent regression algorithms was conducted. Within the scope of sustainable development and circular economy goals, it is thought that this article will make significant contributions to the literature in terms of utilizing these waste materials and determining the earlyage compressive strengths of the concretes produced with high accuracy. [ABSTRACT FROM AUTHOR]

Copyright of International Journal of Engineering Research & Development (IJERAD) is the property of International Journal of Engineering Research & Development and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, the mechanical and transport properties of concrete mixtures containing two raw perlite aggregates, obtained from two different quarries in Turkey, were compared with those of the concrete produced with crushed limestone aggregate. XRD analysis of the perlites showed that the aggregates contain roughly similar crystal components. However, Erzincan perlite was found to contain more amorphous phases. Moreover, water absorption of İzmir perlite ranged from 7.25 to 12.45% which was far above that of the Erzincan perlite with water absorption ranging from 5.08 to 7.45%. However, the 100 and 500 cycles Los Angeles weight losses revealed that the aggregates had a sufficient and uniform hardness. Within the scope of the study, 9 concrete mixtures with three different water/cement ratios (i.e., 0.69, 0.56 and 0.41) were prepared. It was found that the unit weights of the concretes produced with raw perlite aggregate remained within the limits of lightweight concrete and were 15-21% lighter than those of the control concretes. Moreover, the Erzincan perlite-bearing concretes showed 12-41% lower compressive strength that those of the control mixtures. The lowest performance in terms of either mechanical or transport properties were obtained in the İzmir perlite aggregatebearing concrete mixtures. [ABSTRACT FROM AUTHOR]

In this study, the effect of particle size of pozzolinic additives (bottom ash and zeolite) on alkali-silica reaction (ASR) and compressive strength as mechanical properties of cement based mortar was investigated. In order to obtain pozzolanic additive in different particle sizes, the bottom ash/zeolite was subjected to grinding process in 5 different times (0, 30, 60, 180 and 240 minutes) in a ball mill. Concrete mortars were prepared by using different proportions (10, 20 and 30%) of pozzolinic additive in each particle size to replace cement. Natural fine aggregate and CEM-I 42.5 type Protland cement were used in cement based mortars. The amount of expansion of each mortar bar resulting from ASR according to TS 13517 and compressive strength according to TS EN 12390-3 were determined. As a result, it was determined that zeolite was more effective than bottom ash in suppressing ASR occurring in concrete mortar and the lowest ASR expansion value was obtained by 240 minutes grounded and 10% replacement of zeolite by cement. However, when the effect of both pozzolanic additives on the compressive strength of the concrete mortar was compared, it was observed that the bottom ash additive did not have a significant effect on the compressive strength, whereas the zeolite additive reduced the compressive strength a little (10 - 29 %). [ABSTRACT FROM AUTHOR]

In order to predict the ultrasonic pulse velocity results based on the compressive strength results obtained from the experimental results, twelve (12) different cement mortars including mineral admixtures with different proportions were cast. Five curing ages of 1, 3, 7, 28, and 90 days were chosen in order to obtain experimental testing results of compressive strength and ultrasonic pulse velocity. Ultrasonic pulse velocity values have been estimated with regression methods developed via the experimental results of Compressive strength by using Extreme Learning Machine, Support Vector Machine and Group Method of Data Handling. Two distinct approaches were employed for each regression method. In Method 1, ultrasonic pulse velocity values were estimated without compressive strength test results. In Method 2, ultrasonic pulse velocity values were estimated using the compressive strength results. Hereby, first experimental test results of compressive strength and ultrasonic pulse velocity were determined and then estimated results of compressive strength and ultrasonic pulse velocity via regression models were compared in terms of success rate of regression models. When evaluating the performance, the Group Method of Data Handling model achieved the highest test performance among the approaches used in Method 1 and the results for R2 and MSE were 0.856 and 0.037, respectively. In Method 2, the best test performance was achieved with the Group Method of Data Handling model, while the results for R2 and MSE were 0.977 and 0.003, respectively. It has been revealed that the selected regression models have achieved high success in estimating ultrasonic pulse velocity (with/without considering compressive strength). [ABSTRACT FROM AUTHOR]

Copyright of International Journal of Engineering Research & Development (IJERAD) is the property of International Journal of Engineering Research & Development and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of International Journal of Engineering Research & Development (IJERAD) is the property of International Journal of Engineering Research & Development and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Bu çalışmada, yapay sinir ağı (YSA) ve uyarlamalı ağ tabanlı bulanık çıkarım sistemi (ANFIS) ile pomza ve diyatomit içerikli çimento harçlarının basınç dayanımlarının tahmini yapılmıştır. YSA için kademeli ileri geri yayılım algoritması, ANFIS için ise Gauss üyelik fonksiyonu tercih edilmiştir. Modellerin oluşturulmasında toplam 7 tip çimento ile üretilen harçların 2., 7., 28. ve 90. hidratasyon günlerinde belirlenen basınç dayanım sonuçları kullanılmıştır. Modellerin eğitim ve test süreçlerinde; 5 giriş (hidratasyon günü, Portland çimento, pomza, diatomit, su) ve 1 çıkış (basınç dayanımı) parametresi kullanılmıştır. Deney sonuçlarıyla modelden elde edilen sonuçların karşılaştırılması R2, MAPE ve RMSE gibi istatistiksel yöntemlerle gerçekleştirilmiştir. Elde edilen veriler, YSA modeli ile elde edilen sonuçların tüm hidratasyon günleri için hemen hemen gerçek değerlere ulaşıldığını ve bu modelin başarılı bir tahmin modeli olduğunu göstermektedir.

Sulfur polymer concrete (SPC) with its superior mechanical and durability properties has come to the fore in recent years as an alternative construction material to traditional Portland cement concrete (PCC). It is seen that the studies on the modulus of elasticity, which is an important design parameter of concrete, are insufficient in the literature for SPC and are still not considered in the prediction models suggested in the standards. This study aims to examine the compressive strength-modulus of elasticity relationship of SPC comparatively with analytical models proposed by international standards and traditional PPC. As a result of the experimental study, it was determined that the modulus of elasticity of SPC remained at lower values than PCC with similar compressive strength values. It was observed that the analytical models proposed in the standards for PCC could not obtain approximate values for the estimation of the modulus of elasticity of SPC, except for the ACI 363R-92 and NS 3473 standards. A new analytical model was proposed using the experimental data within the scope of this study. The proposed analytical model was statistically compared with the models in the standards that gave close results, and it was determined that the proposed model gave the closest results to the experimental values. [ABSTRACT FROM AUTHOR]

Tons of fly ash are released every year due to the coal burned in thermal power plants that meet 80% of Türkiye's electrical energy needs. Especially considering the low-quality lignite reserves in Türkiye, the recycling rate of the high sulfate fly ash is relatively low. In concrete production, the use of ash containing high SO3 is not allowed due to the limitation of SO3 ratios of fly ash by regulations. Herein, the usability of fly ash, which has a high sulfate content due to the low-quality lignite reserves in Türkiye, and is therefore wholly waste, as a clinker replacement material was investigated. Fly ash, which has been used as a clinker replacement material, was obtained from Afşin Elbistan thermal power plant. Binders were obtained by grinding together the high sulfate fly ash, clinker and gypsum at different rates. The setting times of the mixtures in the fresh cement paste were determined, and the compressive strengths of the hardened samples were examined. As a result of the study, it was concluded that although the high sulfate fly ash extended the setting time by approximately 29% compared to the reference specimen, it increased the 28-day compressive strength of the hardened specimens up to 14%. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Erzincan University Journal of Science & Technology is the property of Erzincan Binali Yildirim Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Duzce University Journal of Science & Technology is the property of Duzce University Journal of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Gerek doğal gerekse yapay puzolanik malzemeler çimento ve beton teknolojisinde yoğun olarak kullanılmaktadır. Özellikle yapay puzolanların kullanımının atık değerlemesi, çevre kirliliğinin azaltılması, enerji kaynaklarının korunması, dayanım ve dayanıklılığa katkısı nedeniyle giderek yaygınlaştığı görülmektedir. Bu amaçla yapılan çalışmanın ilk aşamasında Portland çimento ve yüksek fırın cürufunun fiziksel, kimyasal, mineralojik, termal özellikleri ve bağ yapıları gibi yapısal özellikleri belirlenmiştir. İkinci aşamada yüksek fırın cürufu ağırlıkça %0, %5, %10, %15 ve %20 oranlarında Portland çimento yerine ikame edilerek 5 tipte çimento elde edilmiştir. Üçüncü aşamada ise bu çimentolarla üretilen çimento hamur ve harç örnekleri üzerinde su ihtiyacı, genleşmesi, priz süresi ve basınç dayanımı değerleri belirlenmiştir. Sonuç olarak yapılan deneyler neticesinde elde edilen veriler, Portland çimento ve yüksek fırın cürufunun fiziksel, kimyasal, mineralojik özellikleri ile bağ yapılarına göre su ihtiyacında, priz sürelerinde ve basınç dayanımlarında farklılıklar olduğunu göstermiştir. Nihayetinde endüstriyel bir atık olan yüksek fırın cürufunun çimento ve beton teknolojisinde kullanılmasıyla ekonomik ve ekolojik yarar sağlanabileceği düşünülmektedir.

Copyright of Konya Journal of Engineering Sciences / Konya Mühendislik Bilimleri Dergisi is the property of Selcuk University Journal of Engineering, Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Due to the benefits it provides to concrete technology, environment and economy, the use of industrial byproducts and waste materials such as fly ash and waste vehicle tires has been widely accepted in the construction sector. In this study, the effect of using 5%, 10% and 15% fly ash instead of cement as binder on the fresh and hardened properties of concretes where waste tire is used as 5%, 10% and 15% by volume instead of fine aggregate was investigated. Unit volume weight and consistency properties were determined in the fresh state, and adherence by the pull-out method, compressive and bending strength were determined in the hardened state. As a result, depending on the increase in the amount of tire, the unit weight of fresh concrete decreased and the amount of slump increased, while the compressive, adherence and flexural strengths and modulus of elasticity decreased in hardened concrete. However, fly ash substitution provided an improvement in compressive strength and prevented strength losses. The use of 10% fly ash increased the compressive strength by approximately 30% in concretes with 10% and 15% tire additives. Fly ash increased the adherence strength by 16% and 25%, respectively, in 10% and 15% tire additives. In general, 10% fly ash provided improvement by reducing strength losses in tire-added concretes. The use of fly ash and waste tire in optimum proportions contributes to the usability of tire additives in concrete technology by improving the physical and mechanical properties of tire-added concretes. [ABSTRACT FROM AUTHOR]

Copyright of SDU Journal of Engineering Sciences & Design / Mühendislik Bilimleri ve Tasarım Dergisi is the property of Journal of Engineering Sciences & Design and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Dicle University Journal of Engineering / Dicle Üniversitesi Mühendislik Dergisi is the property of Dicle Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Different methods are used to increase the pozzolanic activity of clay. Muffle or rotary furnaces consume significant amount of energy and require long time for calcination. Microwave technology has potential to be an alternative for the calcination of clays. In this study, the effect of short-term microwave heat treatment on the pozzolanic activity of kaolin was investigated. For this purpose, the strength activity index of the kaolins, which were heat treated at 300, 450, 600 and 800 watts for 10 minutes in a household type microwave oven, were determined. The results were compared with kaolins calcined in the muffle furnace at 600, 700 and 800°C for 1, 3 and 5 hours. The 28-day strength activity index of the kaolins calcined in the muffle furnace varied between 82.5-107.9%, and this value was in between 74.3-80.5% for the microwave heat-treated kaolins. The strength activity index of microwave heat-treated kaolins, being 4.6-13.3% higher than that of the raw kaolin, showed the potential of the microwave heat treatment for calcination. [ABSTRACT FROM AUTHOR]

Copyright of International Journal of Engineering Research & Development (IJERAD) is the property of International Journal of Engineering Research & Development and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Duzce University Journal of Science & Technology is the property of Duzce University Journal of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Bu çalışmada, farklı ayrık lif tiplerinin betonun elastisite modülü üzerindeki etkileri araştırılmıştır. Bu amaçla 260 adet silindirik basınç deney numunesi derlenmiştir. Dikkate alınan lif tipleri çelik, PVA, polipropilen, polyolefin, bazalt ve olefindir. Çalışma sonuçları tüm lif tipleri için kaba agrega miktarının ince agrega miktarına oranının 1.5’i aşması durumunda beton basınç dayanımının azaldığını göstermiştir. Çelik lifli karışımların lif narinlik oranının 60’dan küçük ve eşit olduğu durumlarda elastisite modülü artış gösterirken 60’dan büyük değerler için elastisite modülünün azaldığı görülmüştür. Dikkate alınan tüm lif tipleri için geçerli olan bir elastisite modülü denklemi önerilmiştir. Önerilen denklem deney sonuçları ile ve literatürde yer alan diğer formüllerle karşılaştırılmış ve farklı durumlar için denklemlerin geçerlilikleri sorgulanmıştır.

Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of International Journal of Engineering Research & Development (IJERAD) is the property of International Journal of Engineering Research & Development and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Considering global trends in sustainable and green development as well as the major drawbacks of conventional hydraulic cement, accelerate attempt for finding a suitable alternative and likely cause further development of geopolymeric cements in future. Influences of Nano scale Materials in improving the mechanical properties of ordinary Portland cement have been obviously proved. Despite the widespread use of these materials in different fields of science, for instance, chemicals engineering, materials engineering and even ordinary Portland cement, the effect of Nano scale materials in geopolymers has not been investigated deservedly. The purpose of this study is creating bridges to mitigate these gaps and shortcomings. Very fine silica particles (micro and Nano-silica) effects in ferrochrome slag based geopolymer have been evaluated in this research. Elazığ ferrochrome slag was used as the main aluminosilicate source and then it was blended with Nano silica or silica fume in little amounts in order to accelerate geopolymerization. Nano-silica and silica fume have been used at 2,4,6,8 and 10% of total binder weight in this study due to probe fine silica effect on the mechanical specification of produced material such as compressive strength, Static modulus of elasticity, Tensile Strength and microstructural change. The experimental results show all of these mention mechanical properties have been improved with adding fine silica in geopolymer mixes in optimum percentage of total binder weight. The best percentage of fine silica partial replacement instead of FS is 6% at all of silica fume and three Nano particle size (15, 30 and 45 nm). SEM images assessment demonstrated homogenous and denser texture with acceptable chemical bonds improvements for samples with optimum Nano-silica dosage. Compressive strength increase can be explained by densification of the matrix texture by using of Nano-silica and silica fume at optimum dosage.

Çimento ve puzolanlar bu günün hızlı gelişen yapı sektöründe yaygın olarak kullanılmaktadır. Betonarme yapı tasarımında dayanımın yanında dayanıklılık da çağımızda giderek önem kazanmaktadır. Zeolit gibi puzolanik malzemeler, ekonomik ve ekolojik faktörler nedeniyle çimento ve beton sektöründe yaygın olarak kullanılmaktadır. Çalışmada, Türkiye'de oldukça zengin kaynaklara sahip olan zeolitin ikamesi ile üretilen betonların fiziksel ve mekanik özellikleri belirlenmeye çalışılmıştır. Bu çalışma, sodyum klorür (NaCl) etkisi altındaki zeolit ikameli betonların davranışını araştırmak için yapılmıştır. Bu amaçla zeolit sırasıyla, %0, %10 ve %20 oranlarında Portland çimentosu yerine ikame edilerek 3 farklı çimento elde edilmiştir. Her beton grubu için bu çimentolarla üretilmiş toplam 54 adet 15x15x15 cm ebadında küp örnekler üretilmiştir. Örnekler hazırlanırken çökme miktarı 7 ile 10 cm arasında olacak şekilde beton karışım dizaynı yapılmıştır. Üretilen sertleşmiş beton örnekleri üzerinde birim ağırlık, su emme, görünür boşluk oranı, ultrases geçiş hızı, kapiler su emme, yarmada çekme dayanımı ve basınç dayanımı deneyleri yapılmıştır. Sertleşmiş beton deneyleri, üç farklı beton türü üzerinde, 28 gün 23±2 oC suda, daha sonra NaCl ve beton yaşı faktörünün iki düzeyinde (56 ve 90 gün) kür edilen beton örnekleri üzerinde gerçekleştirilmiştir. Sonuç olarak, sertleşmiş beton örneklerinin basınç dayanımı, yarmada çekme dayanımı, kapilerite katsayısı, ultrases geçiş hızı, görünür boşluk oranı, su emme oranı ve birim hacim ağırlık deneylerinin tümünün birbiri ile uyumlu olduğu belirlenmiştir.

Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Light weight aggregate was produced by rapid sintering of red soil with some admixtures; i) sewage sludge for void formation, ii) sodium carbonate and fly ash for better sintering. Little cylinders were prepared with red soil to investigate the effect of a number of variables, including the fly ash ratio by weight of red soil (12% and 17%), pressing force (1, 3 and 5 KN), and rapid sintering temperature (1050 and 1100°C) on the physical and mechanical properties of light weight aggregate. Compressive strength increased with the increase in fly ash ratio. Considering the highest light weight aggregate specific strength (14,80 MPa / 0,98 ton/m³ = 15,10 kN.m/kg) the optimum production obtained with 17% of fly ash, pressing with 1 kN and sintering at 1050°C. [ABSTRACT FROM AUTHOR]

Copyright of International Journal of Engineering Research & Development (IJERAD) is the property of International Journal of Engineering Research & Development and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Erzincan University Journal of Science & Technology is the property of Erzincan Binali Yildirim Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, the effects of silica fume (SD) and micro SiO2 (MS) additives on the strength properties of geopolymer mortars produced using kaolin were investigated. The binder was prepared by adding 3%, 6% and 9% by weight of SD and MS into the kaolin separately. The binders were activated with NaOH containing 11%, 13%, 15% and 17% sodium (Na) by weight. The mixture consisting of binder, sand, NaOH and water was mixed in the mortar mixer and placed in the molds, and an activation temperature of 110 °C was applied for 24 hours. Then, the samples that were removed from the mold were kept at room temperature for up to 28 days. Unit weight, void ratio, water absorption, ultrasound pulse velocity, flexural and compressive strength tests were performed on the samples. As a result of the experiments, the compressive strength of 21.4 MPa and 45.3 MPa was determined in samples containing 9% SD and 11% Na, 9% MS and 17% Na, respectively. In samples containing 11% and 13% Na by weight, no positive effect of SD and MS was observed on the strength, and SD and MS additives were found to increase the strength in samples produced with 15% and 17% Na. [ABSTRACT FROM AUTHOR]