Sürdürülebilir Kalkınma Amaçları

  • MakaleAçık Erişim2018
    Investigation 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 Erişim2018
    Effect 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
    Web of ScienceTR Dizinİncele
  • MakaleYalnız künye2018Scopus SJRQ2
    X-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.

    AtıfScopus6WoS6OpenAlex1
    ScopusWeb of Scienceİncele
  • MakaleYalnız künye2017
    Mechanical 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.

    • SDG 2 · Açlığa Son
    • SDG 9 · Sanayi, Yenilikçilik ve Altyapı
    AtıfWoS4OpenAlex3
    Web of Scienceİncele
  • MakaleAçık Erişim2017Scopus SJRQ1
    Concretes 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.

    • SDG 12 · Sorumlu Üretim ve Tüketim
    AtıfScopus28WoS24OpenAlex33
    ScopusWeb of Scienceİncele
  • MakaleYalnız künye2016Scopus SJRQ1
    Properties 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.

    • SDG 12 · Sorumlu Üretim ve Tüketim
    AtıfScopus137WoS117OpenAlex149
    ScopusWeb of Scienceİncele
  • MakaleYayıncıda açık erişim2015Scopus SJRQ1
    Monitoring 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.

    • SDG 9 · Sanayi, Yenilikçilik ve Altyapı
    AtıfScopus19WoS17OpenAlex19
    ScopusWeb of Scienceİncele
  • BildiriYalnız künye2012
    USAGE OF BAYBURT STONE IN ROAD INFRASTRUCTURES AS A IMPROVEMENT MATERIAL

    Kamiloglu, Hakan Alper; Yurdagül, Erman; Tekin, Ilker; Cokorilo, O

    Subgrade is one of the most important factor which affects the operating time of highways. Subgrade of highways which are a part of freight transportation network exposes to more pressure. Therefore, stabilization of subgrades becomes more important for these highways. Usage of sustainable and eco friendly resources produce economic and effective solutions for stabilization of highways. BS can be a good example of the solution which are mined in Bayburt city, the north-east of Turkey. Bayburt Stone (BS) is Eocene age and consist of zeolite minerals. Because of containing high value of amorphous silica, tuffic Bayburt stones have pozzolanic activity. Therefore, the stones have binding characteristics when they mix in lime. In this study, It is intended to show that BS waste which obtained from the stone quarries during the stone processing, can be used as a stabilizing material in subbase layers of highways. Within the scope of the study lime and lime - BS mixtures were used to improve clayey subbase layers. In the experimental studies, different amount of 0.2-80 mu m diameter BS and lime mixtures were used and improvement results of lime, lime - BS mixtures were compared. The obtained stabilization materials were tested for clayey soils. In this context nonconfined compression test, shear box, XRD, XRF and Particle Sizer tests, standard compaction and soil classification tests (Liquid-Plastic Limit Test, Sieve Analysis, Hydrometer Analysis) were performed. As a result of study it was observe that the strength of samples which obtained from lime-BS increased remarkably and it's possible to make compaction with lower compaction energies.

  • MakaleYalnız künye2012Scopus SJRQ1
    Determination of the effect of volcanic pumice replacement on macro void development for blended cement mortars by computerized tomography

    Tekin, Ilker; Birgul, Recep; Aruntas, Huseyin Yilmaz

    In this study, the effect of volcanic pumice replacements with different ratios on the macro void development was observed using CT for a period of 100 days. The cured mortar specimens were imaged by X-ray CT on different days of the experiment. Utilizing Hounsfield Unit values as guides, void volumes and ratios were identified and measured by Matlab software. SEM images supported the X-ray CT results. It is shown that X-ray CT analysis is capable of assessing the development of macro voids in the mortar specimens.

    AtıfScopus22WoS21OpenAlex20
    ScopusWeb of Scienceİncele