Browsing by Author "Karakuzu, Kemal"
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Publication Adsorption properties of polycarboxylate ether-based high range water reducing admixture on cementitious systems: A review(Elsevier, 2021-11-05) Karakuzu, Kemal; Kobya, Veysel; Mardani-Aghabağlou, Ali; Felekoğlu, Burak; Ramyar, Kambiz; Karakuzu, Kemal; Kobya, Veysel; MARDANİ, ALİ; Bursa Uludağ Üniversitesi/Mühendislik Fakültesi/İnşaat Mühendisliği Bölümü; 0000-0002-1023-3962; 0000-0003-0326-5015; C-7860-2015; GBH-3020-2022; FEQ-9214-2022Adsorption of polycarboxylateether-based water-reducing admixtures (PCE) on the cement surface affects many properties of cementitious systems, especially fluidity. One of the most important parameters affecting the adsorption behavior of PCE is the anionic group properties. Therefore, understanding the anionic group properties of PCE is of great importance for cement-admixture compatibility. In this study, the effects of PCE's anionic group variation and cement properties on cement-admixture compatibility, especially adsorption, were reviewed based on the studies conducted in the literature. It was observed that phosphate and organo-silane substituted PCEs at certain rates have a positive influence on the fresh state properties of cementitious systems due to adsorption improvement and sulfate resistance. In addition, the fresh state properties of the cementitious system were negatively affected as the C3A content and the increment in fineness of the cement increased the admixture requirement. It was emphasized that the effect of pozzolan utilization on the adsorption properties of PCE in cementitious systems should be considered. Information was given about the properties of PCE recommended for use in the presence of pozzolan.Publication Durability performance and dimensional stability of road concrete containing dry-shake surface hardener admixture(Elsevier, 2021-03-08) Mardani-Aghabaglou, Ali; Karakuzu, Kemal; Kobya, Veysel; Hatungimana, Daniel; MARDANİ, ALİ; Karakuzu, Kemal; Kobya, Veysel; Bursa Uludağ Üniversitesi/Mühendislik Fakültesi/İnşaat Mühendisliği; 0000-0003-0326-5015; 0000-0002-1023-3962; FEQ-9214-2022; GBH-3020-2022; C-7860-2015Durability and dimensional stability problems are emerged in road concrete due to traffic loads and environmental factors. The concrete surface treatment is one of the preferred methods to solve these problems economically. As it is known, surface treatment is applied to the concrete surface as dry-shaking and liquid. It is understood from the literature that there are very limited studies about the use of dry-shake hardener admixture in concrete mixtures. In the present study, the effect of dry-shake surface hardener admixture application on mechanical, durability and dimensional stability properties of concrete mixtures having different w/b ratios were investigated. Totally ten series of concrete mixtures coated with and without dry-shake surface hardener admixture were prepared for this purpose. The slump value of concrete mixtures was determined as 85 +/- 5 mm. Vebe, slump and air content tests were performed for each mixture in fresh state and unit weights of mixtures were calculated. Also, compressive strength, modulus of elasticity, transport properties, abrasion resistance, freeze-thaw resistance and drying shrinkage behavior were investigated on the 7, 28 and 90-day specimens. In the light of the experiment results, compressive strength, modulus of elasticity, water sorptivity, abrasion resistance and drying shrinkage behavior of concrete mixtures were positively affected with adding of dry-shake surface hardener admixture. However, it was found that the dry-shake surface hardener admixture application had no significant effect on water absorption, depth of water penetration under pressure and freezing-thawing performances. (C) 2020 Elsevier Ltd. All rights reserved.Publication Effect of high temperature on polypropylene fiber-reinforced mortars containing colemanite wastes(Elsevier, 2021-11-23) Durgun, Muhammed Yasin; Özen, Süleyman; Karakuzu, Kemal; Kobya, Veysel; Bayqra, Sultan Hüsein; Mardani-Ağhabağlou, Ali; Karakuzu, Kemal; Kobya, Veysel; Bayqra, Sultan Husein; Mardani-Aghabaglou, Ali; Bursa Uludağ Üniversitesi/Mühendislik Fakültesi/İnşaat Mühendisliği Bölümü.; 0000-0003-0326-5015 ; 0000-0002-1023-3962; GBH-3020-2022 ; FEQ-9214-2022 ; CDR-7456-2022 ; C-7860-2015In this study, the effect of polypropylene (PP) fiber utilization ratio on the fresh and some hardened properties of mortar mixtures containing colemanite waste (CW), which mainly contains B2O3, SiO2 and CaO, containing mortar mixtures were investigated. The 17 mortar mixtures were prepared by replacing 0, 1, 3, 5, and 7 wt% of cement with CW and by adding 0, 0.5, 0.75, and 1% by volume of PP fibers to the control mixture. In all mixtures, water/binder ratio, sand/binder ratio and slump-flow values were kept constant as 0.485, 2.75 and 220 +/- 20 mm, respectively. Water reducing admixture requirement of each mixture was determined to provide the target slump-flow range in mortar mixtures. There was a change in the amount of admixture according to the amount of CW and fiber content in the mixture. The 28 and 56-day water absorption capacity, compressive strength and high temperature resistance of mortar mixtures were determined. Strength reduction of specimens exposed to 300 degrees C and 600 degrees C were compared. In addition, thermal and scanning electron microscopy (SEM) analyses were performed on the specimens. According to the test results, with the increase in the amount CW and PP fiber in the mixtures, the admixture demand to provide target flow value and the 28-day water absorption capacity of the mixtures increased, while the 28-day compressive strengths decreased. However, while there was no significant change in the 56-day water absorption capacity and compressive strength values of the specimens containing CW, the water absorption capacity increased and the compressive strength decreased upon the presence of fiber in the matrix. The specimens containing both of CW and PP fiber showed better performance in terms of high-temperature resistance.Publication Effect of polypropylene fiber and shrinkage reducing admixture utilization on water absorption of khorasan mortar(Elsevier, 2022-04-20) Özen, Süleyman; Kaya, Tuğce Isafca; Karakuzu, Kemal; Doğangun, Adem; Ağhabağlou, Ali Mardani; Bursa Uludağ Üniversitesi/Mühendislik Fakültesi; 0000-0002-1023-3962; 0000-0002-1867-7103; 0000-0003-0326-5015; AAR-6126-2020; C-7860-2015It is seen that lime-based mortars are frequently preferred in historical and monumental structures. It is known that damages occur depending on the materials used in the building over time. In restoration works, mortars compatible with the original material of the building should be used. For this reason, the use of lime-based mortars is common during restoration work. Accordingly, attention should be paid to the physical and mechanical properties of the mortar to be produced. This study aims to determine the effect of polypropylene (PP) fiber and shrinkage reducing admixture (SRA) on the water absorption properties, which is used to improve the strength and durability properties of Khorasan mortar. As a result, it was determined that PP fiber utilization increased the water absorption ratio due to the formation of voids in the mortars. However, the use of SRA decreased the water absorption ratio due to its effect on the drying shrinkage behavior of the mortars. In cases where both are used together, the effect of fiber use was more dominant. Copyright (C) 2022 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the Third International Conference on Aspects of Materials Science and Engineering.Publication Effects of material properties on the mechanical and durability behaviors of khorasan mortar mixtures: A review(Taylor, 2021-03-05) İsafça, Tuğçe; Karakuzu, Kemal; Özen, Süleyman; Doğangün, Adem; Mardani-Aghabaglou, Ali; İsafça, Tuğçe; Karakuzu, Kemal; DOĞANGÜN, ADEM; MARDANİ, ALİ; Bursa Uludağ Üniversitesi/Mühendislik Fakültesi/İnşaat Mühendisliği Bölümü; 0000-0002-9331-1339; 0000-0002-1023-3962; 0000-0002-1867-7103; 0000-0003-0326-5015; AAR-6126-2020; C-7860-2015; GBH-3020-2022; GFM-1667-2022Historical buildings are an important piece of our cultural heritage. It is important that the materials used in the preservation, repair and reinforcement applications of these structures should be compatible with the existing structure. In many of the historical buildings in Turkey, it was reported use of the Khorasan mortar as the masonry mortar and plaster. Khorasan mortar contains slaked lime as a binder, river sand, and clayey materials as aggregate, which are fired at high temperature. It was emphasized that this mortar is an essential building material widely used in the construction and repair of historical buildings from past to present. In this study, the effects of binder, aggregate, chemical admixture, organic admixture, and fiber properties on the mechanical and durability performance of Khorasan mortar and lime-based mortar mixtures were investigated. For this purpose, a comprehensive literature research was carried out on this subject. In addition, the positive and negative effects of these materials on the mortar mixture were emphasized.Publication Effects of shrinkage reducing admixture and polypropylene fiber utilization on some fresh state, mechanical and durability properties of khorasan mortar(Taylor & Francis Inc, 2022-07-16) Özen, Süleyman; İsafca-Kaya, Tuğce; Karakuzu, Kemal; Mardani, Ali; MARDANİ, ALİ; Doğangün, Adem; DOĞANGÜN, ADEM; Bursa Uludağ Üniversitesi/Mühendislik Fakültesi/İnşaat Mühendisliği Bölümü.; 0000-0002-1023-3962; 0000-0001-5522-427X; 0000-0003-0326-5015; 0000-0002-1867-7103; AAR-6126-2020; C-7860-2015; AAJ-6415-2021This study aimed to improve the mechanical and durability properties of Khorasan mortar, a type of lime-based mortar, using polypropylene shrinkage reducing admixture (SRA) and fiber. In addition to the control mixture without fiber and chemical admixture, three series of mixtures were prepared. The first series contains 0.4-0.6-0.8% polypropylene fiber by total volume; the second series contains SRA at the 0.05-0.1-0.15% by binder weight; the third series consists of mixtures containing both fiber and the SRA. Within the scope of the study, some fresh state, mechanical and durability properties were determined. The results show that utilization of fiber and SRA reduced the length change depending on drying-shrinkage and mass loss due to abrasion compared to the control mixture. In addition, the 90-day flexural and compressive strength values for all mixtures were lower than the 28-day results. It was determined that the decrease in strength values is less than the control mixture with the utilization of fiber and SRA because of the degradation in drying-shrinkage.Item Su azaltıcı katkı anyonik monomer değişiminin farklı C₃A içeriğindeki çimentolu sistemlerin davranışına etkisi(Bursa Uludağ Üniversitesi, 2023-03-21) Karakuzu, Kemal; Mardani, Ali; Bursa Uludağ Üniversitesi/Fen Bilimleri Enstitüsü/İnşaat Mühendisliği Anabilim Dalı.; 0000-0002-1023-3962Bu tez çalışmasında, polikarboksilat esaslı su azaltıcı katkı (PCE) anyonik grup içeriğinin farklı oranda C₃A ve uçucu kül içeren çimentolu sistemlerle uyumu incelenmiştir. Tez çalışması 2 farklı aşamadan oluşmuştur. 1. aşamada, kontrol katkısının %100 karboksilat olan anyonik grubu farklı oranlarda fosfat ve sülfonat grupları ile ikame edilmiştir. 2. aşamada ise kontrol, fosfat ve sülfonat ikameli PCE’lerin anyonik yük yoğunluğu değiştirilmiştir. Böylece, toplamda 19 farklı PCE sentezlenmiştir. %2.13, %3.60, %6.82 ve %9.05 olmak üzere 4 farklı C₃A oranına sahip çimento kullanılmıştır. Çimento, ağırlıkça %0, %15, %30 ve %45 oranında uçucu kül ile ikame edilerek farklı PCE’ler içeren hamur ve harç karışımları hazırlanmıştır. Hazırlanan karışımların taze hal, reolojik ve bazı sertleşmiş hal özellikleri araştırılmıştır. Elde edilen sonuçlara göre, anyonik grup içeriği ve anyonik yük yoğunluğu değişimi, PCE’nin performansını önemli ölçüde etkilemiştir. Fosfat ve sülfonat ikame oranının sırasıyla, %9 ve %5 oranına kadar artması ile karışımların incelenen özellikleri iyileşmiştir. Ayrıca, PCE anyonik yük yoğunluğunun artması ile akış performansı olumlu etkilenmiştir. Bu bağlamda, en iyi performans %5 oranında sülfonat ikame edilen ve anyonik yük yoğunluğu yüksek PCE ile elde edilmiştir. İlaveten, söz konusu özellikler açısından %3.60 oranında C₃A içeren karışım en iyi performansı sergilemiştir. C₃A içeriğinin belli bir değere kadar artışı ile karışımların sertleşmiş hal özellikleri olumlu etkilenmiştir. Ayrıca, çimentonun C₃S içeriği ve inceliğinin de karışımların incelenen özellikleri üzerine büyük etkiye sahip olduğu anlaşılmıştır. Uçucu kül ilavesi ile karışımların PCE ihtiyacı ve zamana bağlı kıvam koruma performansı olumlu, ancak, diğer taze özellikleri olumsuz etkilenmiştir. Ayrıca %45 oranında uçucu kül içeren hamur ve harç karışımlarına PCE ilavesi, dispersiyon etkisi sayesinde karışımların homojen şekilde hazırlanmasına katkı sağlamıştır. %15’in üzerinde uçucu kül ikame edilmesi ile harç karışımlarının basınç dayanımı azalmıştır.Item Su azaltıcı katkılarda sülfonat ve fosfat anyonik monomerlerin kendiliğinden yerleşen betonların taze hal ve mekanik özelliklerine etkisi(Bursa Uludağ Üniversitesi, 2022-07-20) Altun, Muhammet Gökhan; Özen, Süleyman; Karakuzu, Kemal; Mardani, Ali; Uludağ Üniversitesi/Mühendislik Fakültesi/İnşaat Mühendisliği Bölümü.; 0000-0002-1023-3962; 0000-0003-0326-5015Bu çalışmada, polikarboksilat-eter esaslı su azaltıcı katkının anyonik monomer içeriğinin kendiliğinden yerleşebilen beton (KYB) karışımlarının çeşitli taze ve sertleşmiş hal özelliklerine etkisi araştırılmıştır. Bu amaçla, anyonik monomeri %100 karboksilat olan kontrol katkısına ilaveten, kontrol katkısının anyonik monomerinin %10 ve %30 oranında sülfonat ve fosfat ile ikame edilmesiyle birbirinden farklı 5 adet su azaltıcı katkı sentezlenmiştir. Elde edilen sonuçlara göre, su azaltıcı katkı anyonik monomerinin sülfonat ile ikame edilmesi, karışımların katkı ihtiyacını artırırken; zamana bağlı yayılma performanslarını olumlu yönde etkilemiştir. Fosfat ikame edilmesi durumunda ise karışımların katkı ihtiyacı azalırken zamana bağlı yayılma performansı olumsuz etkilenmiştir. Tüm karışımlar içerisinde taze hal özellikleri açısından en iyi performans %10 sülfonat ikame edilen katkı ile elde edilmiştir. Anyonik monomer değişimi, KYB karışımlarının basınç dayanımları, su emme oranları, ultrases geçiş hızları (UPV) ve dinamik elastisite modüllerinde önemli bir değişikliğe sebep olmamıştır.