Sürdürülebilir Kalkınma Amaçları
Yayınları
12 →- MakaleYayıncıda açık erişim2023Scopus SJRQ4Development of Alkali-Activated Binders from Recycling Regional Tuff and Marble Wastes
Tekin, İlker; Ciza, Baraka; Gökçe, H.S.
The sustainability goals of the developing world have led many industries to recycle their wastes and reduce emitting greenhouse gases. To contribute to these environmental responsibilities, this study has focused on the development of eco-friendly binder materials from regional ground tuff and marble wastes by the activation of sodium silicate (Na2SiO3) and sodium hydroxide (NaOH) or slaked lime (Ca(OH)2). The results of this study show that alkali-activated composites experienced expansion, drying shrinkage cracking, leaching, and efflorescence. The compressive strength values of the NaOH and Ca(OH)2-activated pastes reached up to 15 MPa and 9 MPa, respectively. A reduction in NaOH molarity improved the compressive strength, dimensional stability, and durability of tuff-based alkali-activated pastes.
AtıfScopus5OpenAlex3
İncele - MakaleAçık Erişim2021Scopus SJRQ3A novel approach to finding optimum operating conditions of design factors for the grinding experiment
Uçurum, Metin; Özdemir, Akın; Teke, Çağatay; Tekin, İlker
The efficiency of grinding experiments is an important issue for many industries. In this paper, a central composite design-based methodology was proposed to investigate the four design factors that affect the particle sizes. The four design factors were specified as mill speed (% of Nc), ball filling ratio (fc), powder filling ratio (jb) and grinding time (min). Another important issue was how to obtain an optimum operating condition for four design factors. For this particular purpose, a novel dual response optimization model was proposed using the particle sizes (d 10, d 50, and d 90) and the span value concept. This proposed approach was compared to the desirability function-based optimization concept. The verification study of the experiment was also carried out. The results of the grinding experiment runs showed that the optimum operating conditions were mill speed 73.495% of Nc, ball filling ratio 0.354, powder filling ratio 0.157, and grinding time 70 min. In addition, d 10, d 50, and d 90 were found 3.31 µm, 12µm, and 45.6 µm, respectively. The span value was also found at 3.52.
AtıfScopus3WoS3OpenAlex4
İncele - MakaleYalnız künye2021Scopus SJRQ1A regional supplementary cementitious material for the cement industry: Pistachio shell ash
Tekin, İ.; Dirikolu, İ.; Gökçe, H.S.
The recycling of agricultural wastes in cementitious products has recently been a trendy approach for the sustainability goals of the world as it ensures economic and ecological advantages in addition to the safe disposal of these wastes. In this regard, the potentiality of a biomass ash obtained from the incineration of pistachio shell to serve as a supplementary cementitious material is documented in the present study. An increase of up to 30% in the amount of pistachio shell ash resulted in the proportional increase of both water requirement and setting time of the ordinary Portland cement by up to 54% and 300%, respectively. The incorporation of up to 20% pistachio shell ash into the cement yielded specimens of comparable or higher compressive strength values relatively varying between 98% and 117% at the 28 days and later curing ages. Beside the cementitious property, it was observed that a presence of graphitic structures in the pistachio shell ash remarkably improved the mechanical and the microstructural properties of cement mortars. In conclusion, at least 10% incorporation of this ash into the cement is highly recommended for the cement industry as it is beneficial in achieving the highest ultimate (400-day) compressive strength and promotes no loss on the early (2-day) compressive strength.
AtıfScopus41WoS38OpenAlex45İncele - MakaleAçık Erişim2018Investigation of Superplasticiser Effect on Blended Cements Replaced By Bottom Ash
Tekin, Ilker; Tekin, Duygu
In the study, the main aim was determined conformity between blended cements and superplasticizer (SP) with fineness of mineral additives. Within this scope, compressive strength test and flow table test were performed on the cement mortars and standard consistency, setting times and soundness tests were performed on cement pastes which prepared with blended cements. In the experimental studies, bottom ash from Yatagan thermal power plant which was used after grinded size from 2 mm to 120 Am and 60 Am sizes was replaced with CEM I 42.5R type cement by weight 0%, 10%, 20% and 30%. Moreover superplasticizer additives which contained poly naphthalene sulfonate (PNS) from different companies were tried in blended cements According to the results, fineness of mineral additives increased the compressive strength of the mortars and accelerated setting times. PNS based SP's affects fresh paste behaviors such as reducing initial setting times and retarding finish setting times Another result is that company differences in PNS based chemical additives is significant parameter with cement conformity and this parameter makes up significant effects on fresh cement paste.
- MakaleAçık Erişim2018Effect of the polynaphtalene sulfonate based superplasticizer on mechanical and physical properties of blended cement replaced with Bayburt Stone at different fineness
Tekin, Ilker; Tekin, Duygu
In this study, grinded Bayburt Stone has pozzolanic property with 45 mu m and 125 mu m fineness was replaced with PC 42.5R (CEM-I) type cement at ratio of 0%, 10%, 20%, and 30% by weight. The aim of this study was made up in two phase, one of them was to investigate the effects of Bayburt Stone waste contain zeolite with different fineness on physical and mechanical properties of composite cements and the other one was to investigate behavior of same superplasticizer belong to two different company. Standard consistency, setting time and volume expansion tests are performed on the cement pastes and compression strength and flow tests are performed on the cement mortars. Mortar specimens are kept in standard curing for 28 days, than compressive strength test are performed at the ages of 2, 7 and 28 days. As a result, changes in specific surface area depending on the particle size distribution of mineral additives makes significant different on the physical, mechanical and rheological properties of cement mortars. In this study, it was determined that same type of superplasticizers which had different companies could be used in blended cement replaced with Bayburt stone.
AtıfOpenAlex1TR Dizin1
İncele - MakaleYalnız künye2018Scopus SJRQ2X-ray CT monitoring of macro void development in mortars exposed to sulfate attack
Tekin, Ilker; Birgul, Recep; Aruntas, Huseyin Y.
This study reports the results of nondestructive monitoring of macro void developments in mortars manufactured with both ordinary Portland cement and sulfate resistant cement. Two types of curing were utilized; tap water curing and another curing environment that contains 5% Na2(SO4) solution. Being the primary objective of this study, macro void developments of the mortar specimens were monitored by X-ray Medical Computerized Tomography. Compressive strength tests and water absorption tests were conducted on specimens that were kept in both curing environments for a duration of 560 days. Data analyses yielded consistent results among the three tests used in this experimental study. Macro void ratios of mortars decreased at the beginning of experiments for a certain period; afterwards, macro void ratios increased. The objective of this study was accomplished as anticipated since X-CT image analysis was able to nondestructively monitor macro void development process in cement mortars.
AtıfScopus6WoS6OpenAlex1İncele - MakaleYalnız künye2017Mechanical Properties of Conventional Concrete Produced With Different Type of Aggregates in Bayburt Region
Tekin, Ilker; Kotan, Turkay; Yurdakul, Muhammet; Öner, Erdal
In this study, the limestone, natural aggregate, serpentine and Bayburt stone located in the province of Bayburt used as aggregate in conventional concrete production. In the experiments, the cement dosage and workability were kept constant. Slump, Ve-Be, unit weight and the highest temperature values in first 2 hours of the fresh concrete were measured. The concrete samples prepared with Bayburt stone were cured for 90 days and the others were cured for 28 days in lime-saturated water. Strain-stress data and water absorption values were measured on the hardened concretes at 7 and 28th days age through the records of stress and strain data during compressive strength tests. According to results of this study, the compressive strengths of the concrete samples with limestone, natural aggregate and serpentine were on average of 40, 35 and 5 MPa, respectively, on the 28th day. Also, in concrete samples with Bayburt stone, the compressive strengths were reached to 16 MPa for 28 days and to 22 MPa for 90 days.
AtıfWoS4OpenAlex3İncele - MakaleAçık Erişim2017Scopus SJRQ1Concretes with synthetic aggregates for sustainability
Tekin, Ilker; Yasin Durgun, Muhammed; Gencel, Osman; Bilir, Turhan; Brostow, Witold; Hagg Lobland, Haley E.
We have used waste marble aggregates, marble dust and fly ash from thermic power plants as fillers in concretes for replacing natural aggregates. We have used two different kinds of cements. After curing, we have determined the workability (by slump tests), air content, unit weight, Schmidt hardness, ultrasound pulse velocity, compressive strength and carbonation depth. The concretes containing waste marble at least match or exceed the workability and strength of the control concrete type. Fly ash significantly improves the workability. Utilizing waste marble aggregate at the replacement ratio of 100% along with waste marble dust, fly ash and pozzolanic cements in concrete leads to lower cost – achieving at the same time environmentally friendly production process with decreased consumption of natural resources and energy. Our work also contributes to enhancement of sustainability by finding a use for marble waste and fly ash.
AtıfScopus28WoS24OpenAlex33İncele - MakaleYalnız künye2016Scopus SJRQ1Properties of NaOH activated geopolymer with marble, travertine and volcanic tuff wastes
Tekin, Ilker
In this study, geopolymer composite pastes (GCM) were produced using wastes of marble, travertine and natural pozzolan, with 1 M, 5 M and 10 M NaOH as alkali-activator. Curing process were done at 20, 45 and 75 °C temperatures for 24 h in an oven. And after that GCMs were exposed to wet and dry condition separately. The strength tests were done on the 2nd, 3rd, 7th, 28th and 90th days of curing period. The compressive strengths of the specimens in the wet conditions were reduced depending on time, but in dry conditions were increased with curing time.
AtıfScopus137WoS117OpenAlex149İncele - MakaleYayıncıda açık erişim2015Scopus SJRQ1Monitoring macro voids in mortars by computerized tomography method
Tekin, Ilker; Birgul, Recep; Ozgur Yaman, Ismail; Gencel, Osman; Yilmaz Aruntas, Huseyin
This study aims to investigate the use of ground pumice powder (PP) in cement production and to monitor void developments in mortars by X-ray Computerized Tomography (CT) which is a nondestructive test method. PP-blended cements were produced by replacing ordinary Portland cement with PP at 0% (control), 5%, 10% and 15% by weight. Paste and mortar specimens were manufactured by these blended cements. Some of the physical and mechanical tests are carried out on these mortar specimens. Experimental results showed that macro void developments in 100-day period for mortars with different PP replacement ratios exhibited different reduction in void ratios.
AtıfScopus19WoS17OpenAlex19İncele
Tam Kayıt
| Alan | Değer | Dil |
|---|---|---|
| dc.date.accessioned | 2026-10-29T19:09:43.919996944Z | |
| dc.date.available | 2026-10-29T19:09:43.919996944Z | |
| dc.identifier.uri | https://rdlopen.rawdatalibrary.net/r/bayburt/12561 | |
| dc.rights | info:eu-repo/semantics/openAccess | |
| dc.title | Tekin, Ilker | |
| person.affiliation.name | Bayburt University, Faculty of Engineering, Department of Civil Engineering, 69000, Bayburt, Turkey | |
| person.familyName | Tekin | |
| person.givenName | Ilker | |
| person.identifier.scopus | 35367279600 | |
| person.name.variant | Tekin, İ. | |
| person.name.variant | Tekin, I | |
| person.status | unverified |