Kolemanit ve Alüminyum Talaşı İkamesinin Geopolimer Harçlarda Taze, Mekanik ve Termal Özellikleri Üzerindeki Etkisi

Öz

Son yıllarda, geleneksel Portland çimentosu bazlı sistemlerin çevresel etkisini azaltma ihtiyacından kaynaklanan sürdürülebilir ve yüksek performanslı inşaat malzemelerinin geliştirilmesi önemli bir ivme kazanmıştır. Bu çalışmada, bağlayıcı bileşenler olarak yüksek fırın cürufu (BFS) ve 45 mikronluk kolemanit (K) kullanılarak, agrega olarak alüminyum talaşı, demir tozu ve kırılmış taş ile jeopolimer harç (GM) üretilmiştir. K ikame oranının (%0, %10 ve %20) ve alüminyum talaşı içeriğinin (%2 ve %4) harçların taze ve sertleşmiş özelliklerine etkilerini araştırmak için altı karışım serisi tasarlanmıştır. Tüm seriler için su/bağlayıcı oranı, alkali/bağlayıcı oranı, sodyum silikat/sodyum hidroksit (NS/NH) oranı ve NaOH konsantrasyonu sırasıyla 0,30, 0,50, 2 ve 10 M'de sabit tutulmuştur. Numuneler 50 mm küp kalıplara döküldü, plastik filmle sarıldı ve 60°C'de 48 saat fırın kürleme işlemine tabi tutuldu. Deneysel program, yayılma (akış), basınç dayanımı, su emme, gözeneklilik ve 800°C'de yüksek sıcaklık dayanımı testlerini içeriyordu. Çalışmanın sonuçları, en yüksek basınç dayanımı değerlerinin %10 K ikamesi ve %2 alüminyum talaşı içeriğinde elde edildiğini, tüm karışımların yüksek sıcaklıklara maruz kaldığında kütle kaybı yaşadığını, ancak bu kaybın K20 serisinde sınırlı olduğunu göstermektedir.

Anahtar Kelimeler

• Geopolimer harç
• kolemanit
• alüminyum talaşı
• demir tozu
• işlenebilirlik
• sertleşmiş ve durabilite özellikleri

Effect of Colemanite Replacement and Aluminium Shavings on the Fresh, Mechanical, and Thermal Properties of Geopolymer Mortars

Öz

In recent years, the need to reduce the environmental impact of conventional Portland cement-based systems has accelerated research into the development of sustainable and high-performance construction materials. In this study, geopolymer mortars (GMs) were produced using blast furnace slag (BFS) and colemanite (K) with a fineness of 45 µm as binder components, while aluminum machining chips, iron powder, and crushed stone were used as aggregates. Six different mixture series were designed to investigate the effects of the colemanite replacement ratio (0%, 10%, and 20%) and aluminum machining chip content (2% and 4%) on the fresh and hardened properties of the mortars. For all mixtures, the water-to-binder ratio, alkali activator-to-binder ratio, sodium silicate-to-sodium hydroxide (NS/NH) ratio, and NaOH concentration were kept constant at 0.30, 0.50, 2.0, and 10 M, respectively. The specimens were cast into 50 mm cubic molds, wrapped with plastic film, and subsequently subjected to oven curing at 60°C for 48 h. The experimental program included flow, compressive strength, water absorption, porosity, and high-temperature resistance tests at 800°C. The results showed that the highest compressive strength, approximately 12 MPa, was obtained for the mixture containing 10% K and 2% aluminum machining chips. The water absorption and porosity values ranged from approximately 14–18% and 26–33%, respectively, and both properties increased with an increase in the colemanite content from 10% to 20%. Following exposure to 800°C, all mixtures exhibited a mass loss ranging from 7% to 10%. The lowest mass loss, 7.37%, was recorded for the K204A series, whereas the highest mass loss, approximately 10%, was observed for the S1004A series.

Anahtar Kelimeler

• Geopolymer mortar
• colemanite
• aluminium shavings
• iron powder
• workability
• hardened and durability properties

Kaynakça

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