Sürdürülebilir Kalkınma Amaçları

• 5
• 3
• 1

• MakaleAçık Erişim2026Scopus SJRQ1/r/munzur/1515
  Optimization, high-temperature resistance, and sulfate durability of basalt powder–blended alkali-activated slag mortars

  Arslan, Furkan; Dener, Murat; Karataş, Mehmet; Benli, Ahmet

  This study investigates the feasibility of using basalt powder (BP), an industrial by-product with limited reactivity, as a partial substitute for granulated blast furnace slag (GBFS) in alkali-activated systems. A comprehensive experimental program was conducted in two stages: first, a systematic optimization was performed by varying mixture parameters, including BP content, alkali dosage, activator modulus, and curing temperature to evaluate compressive strength development; second, selected binder compositions were used to produce self-compacting mortars, which were further examined for flexural strength, high-temperature resistance, and sulfate durability. The results demonstrated that moderate substitution levels (up to 20–30 % BP) could achieve satisfactory compressive strength, particularly under elevated curing temperature (60 °C) with 8 % Na2O and low to moderate modulus values. At 300 °C, mixtures with 20 % BP exhibited strength enhancement due to additional geopolymerization, demonstrating superior thermal stability compared to the control. Crucially, the incorporation of BP enhanced sulfate resistance, with the 40 % BP mixture exhibiting a slight increase in compressive strength after long-term exposure, in contrast to the marked deterioration of the GBFS-only system. Consequently, this study demonstrates that BP can be effectively utilized as a sustainable binder component, offering a practical solution for waste management while enhancing the durability of alkali-activated mortars against aggressive conditions.

  • 
  • 
  AtıfScopus15·WoS13·OpenAlex10

  İncele
• MakaleYayıncıda açık erişim2026Scopus SJRQ1/r/munzur/1489
  Experimental study of an alternative precast concrete beam–column connection with embedded steel block detail

  Baltaci, Alihan; Sunca, Fezayil; Şahi̇n, Muhammed Cihat; Şen, Doğa; Keçeci̇, Bedirhan; Polat, Alper; Altunişik, Ahmet Can

  Precast systems have gained increasing popularity due to their advantages in construction speed, cost efficiency, and quality control. However, past earthquakes have revealed that beam–column connections are often the most vulnerable regions in precast structures, making their seismic performance a critical area of investigation. This study investigates the cyclic behavior of two full-scale precast specimens with different beam–column connection configurations: a code-compliant, Moment-Resisting Emulative-Welded Connection detail (MRCON) and an alternative Embedded Steel Block Connection detail (ESBCON). Both specimens were tested under quasi-static reversed cyclic loading to evaluate their hysteretic response, energy dissipation, stiffness degradation, residual displacements, and modal characteristics. The results demonstrate that while MRCON provided higher initial stiffness and energy dissipation, it experienced severe localized damage and rapid structural deterioration at larger drift ratios. In contrast, the embedded steel block in ESBCON successfully distributed the damage across a wider joint region, leading to a more gradual stiffness reduction and slightly lower residual displacements. Although the overall structural efficiency of ESBCON was partially hindered by the slippage of the steel block, it achieved a competitive level of moment transfer capacity compared to the conventional welded connection detail, highlighting its potential as a damage-distributing alternative once slip-mitigating modifications (surface roughening to enhance bond and embedding within the column) are implemented.

  • 
  İncele
• MakaleYalnız künye2024Scopus SJRQ1/r/munzur/1981
  Resistance to magnesium sulphate attack of binary and ternary cementless self-compacting alkali-activated mortar

  Şahin Yön, Merve; Karataş, Mehmet

  The aim of this study is to investigate the effect of sulphate on self-compacting alkali-activated mortars (SCAAMs) produced using volcanic scoria (V), boron waste (B) and granulated blast furnace slag (G) together with alkali activators. Thus, the production of cement-free alkali-active mortar by recycling waste and reducing the CO2 effect increases the importance of this study. The fact that the waste material is provided free of charge and that V is readily available from nature provides economic advantages in the production of these mortars. In this experimental study, magnesium sulphate solution was utilized to define the sulphate resistance of SCAAMs. In binary SCAAMs, B was used with G in a ratio of NS:NH = 3.0, with an increase from 5 % to 15 %; in ternary mixtures, B was used together with G and V in the same proportions, in a ratio of NS:NH = 1.0. The tests involved immersion in 5 % magnesium sulphate solution for 1, 3 and 6 months. Mass development, compressive strength, visual inspection and microstructural changes were investigated. In general, the binary SCAAMs performed better in magnesium sulphate solution than the ternary SCAAMs, except in the 6th month. Considering the samples with the highest B content, a 100 % loss of compressive strength occurred in the B15G85 sample under the influence of sulphate for 6 months, while a loss of compressive strength of about 15 % occurred in the B15G40V45 sample. The results showed that the increase in B content caused a severe deterioration of the sulphate effect in the samples over time and that the V additive had a positive effect on the sulphate resistance.

  • 
  AtıfScopus26·WoS23·OpenAlex19

  İncele
• MakaleAçık Erişim2022Scopus SJRQ1/r/munzur/3047
  Evaluation of the mechanical properties and durability of self-compacting alkali-activated mortar made from boron waste and granulated blast furnace slag

  Yön, Merve Şahin; Karataş, Mehmet

  The production of high-strength alkali-activated mortar and concrete by using waste materials instead of cement in order to reduce the amount of carbon dioxide released to nature in cement production is an important study that attracts the attention of researchers. In this study, self-compacting alkali-activated mortar samples were produced using boron waste (BW) and granulated blast furnace slag (GBFS). Prismatic samples of 40 × 40 × 160 mm and cubes of 50 × 50 × 50 mm were produced, in which 0%, 5%, 10%, 15%, 20%, 25% of BW were used. To achieve self-compacting alkali-activated mortar (SCAAM) slump-flow test method was conducted by per The European Federation of Specialist Construction Chemicals and Concrete Systems (EFNARC) guidelines. The samples prepared using Na2SiO3 (NS)/NaOH (NH) = 3.0 were exposed to oven curing at 60 °C and 100 °C for 3 days. The flexural and compressive strength (CS) values of 3, 28 and 90 days were obtained for the samples whose curing period was completed. According to the mechanical strength results, influence of capillary water absorption, porosity, water absorption and density and freeze-thaw from durability tests were carried out. After experimental tests, Scanning Electron Microscope (SEM) and Energy-dispersive X-ray Spectroscopy (EDS) images were utilized to determine microstructures of the samples. As a result of the study, it was determined that the highest strengths were obtained at the curing temperature of 60 °C. Also, it was seen that mechanical strengths and durability decreased with the increase in the BW ratio in the mixtures.

  • 
  • 
  AtıfScopus31·WoS28·OpenAlex33

  İncele
• MakaleYalnız künye2021Scopus SJRQ1/r/munzur/2717
  Bacterial crack healing in metakaolin based geopolymer mortars

  Yılmazer Polat, Berivan; Uysal, Mucteba

  Geopolymer mortars have emerged as an environmentally friendly binding alternative to conventional cement. However, the gaps in their structure and early cracks reduce their service life. There are various bacterial healing studies in the literature that have been conducted on cemented mortar cracks. Nevertheless, the present study focuses on the healing of metakaolin based geopolymer mortar cracks. For this purpose, mortars with different molarities were prepared with two different endospore forming methods that did not require encapsulation or mixed chemical processes for the bacterial crack repairs on the geopolymer mortars. These mortars were then left in different healing environments with crack damage. The samples were tested using physical, optical and internal structure analyses. As a result, the cracks were improved by reducing the amount of gaps in the samples. The results showed that it is possible to bacterially repair early cracks in new generation ceramic materials with alkali-activated mortars and reduce the amount of gaps.

  • 
  AtıfScopus41·WoS35·OpenAlex36

  İncele
• MakaleYalnız künye2021Scopus SJRQ1/r/munzur/2345
  Identification of failure mechanisms in existing unreinforced masonry buildings in rural areas after April 4, 2019 earthquake in Turkey

  Yön, Burak

  Many unreinforced masonry buildings are completely destroyed after destructive earthquakes but, their failure mechanisms cannot be precisely determined. More specifically damage to such buildings is evinced during low or moderate magnitude earthquakes. The aim of this study is to identify the failure mechanisms of existing unreinforced masonry buildings and present a reconstruction strategy or offer strengthening procedures, in order to inhibit damage to masonry structures after destructive earthquakes. For this purpose, a moderate magnitude earthquake which occurred on April 4, 2019 near the township of Sivrice in Elazığ city, in the east of Turkey, was investigated. The magnitude of the studied seismic motion was expressed as Mw=5.2 by the Ministry of Interior Disaster and Emergency Management Presidency. Although this seismic effect was a moderate magnitude earthquake, significant failures occurred. Many masonry buildings and adobe dwellings in the villages of Sivrice were severely damaged by the earthquake. For field observations, ten villages located around the epicentre were visited 65 dwellings were observed and the damage patterns were assessed in detail. The observations showed that the main reasons for the damage to the dwellings were weak structural detailing of wall-to-wall and wall-to-roof connections, inhesion of earthen roofs, and a lack of bond beams in the structural walls. According to field observations, it is deduced that the performance of the undamaged masonry dwellings after earthquakes does not prove that they have adequate seismic safety. Therefore, reinforcing methods (shotcrete implementation, decreasing of space, corner reinforcing etc.) and innovative strengthening procedures (fibre reinforced polymer) are recommended for the undamaged existing unreinforced buildings at the end of the paper.

  • 
  • 
  AtıfScopus53·WoS48·OpenAlex56

  İncele