Sürdürülebilir Geopolimer Harçların Yaşam Döngüsü ve Mekanik Özelliklerinin Değerlendirilmesi: Farklı Senaryolar Üzerine Bir Çalışma

Yıl 2025, Cilt: 1 Sayı: 1, 44 - 59, 31.01.2025

Ezgi Örklemez , Brial Asif Hayi Paka , Ahmet Ceylan Serhan İlkentapar , Uğur Durak , Okan Karahan , Cengiz Atiş

Öz

Uçucu kül esaslı geopolimer bağlayıcıların mekanik özellikleri inşaat ve yapı sektöründe kullanımı için önem arz etmektedir. Ayrıca inşaat ve yapıda kullanılacak malzemelerin mekanik özelliklerinin yanı sıra iklim değişikliği ile mücadelede Avrupa Yeşil Mutabakatı’nda (European Green Deal) yer alan çevresel hedefler inşaat sektörünü de yakından ilgilendirmektedir. Bu kapsamda bu çalışmada, bağlayıcı olarak F sınıfı uçucu kül kullanılarak üretilen geopolimer numunelerin mekanik özellikleri ve çevresel etkileri üzerinde diatomit ikamesinin etkisi araştırılmıştır. Karışımlarda, bağlayıcı malzeme ağırlıkça %1, %2, %3, %4 ve %5 oranlarında diatomitile ikame edilerek geopolimer harçlar üretilmiştir. Geopolimer numunelere 90°C'de 24, 48 ve 72 saat ısıl kür uygulanmıştır. Geopolimer numuneler üzerinde farklı kür sürelerinde eğilme ve basınç dayanımı deneyleri yapılmıştır. Ayrıca numunelerin mikro yapısını incelemek için diatomit ikameli geopolimer hamurların FESEM görüntüleri incelenmiştir. Elde edilen sonuçlara göre %1, %2 ve %3oranlarındadiatomit içeren harçların eğilme ve basınç dayanımlarında artış olduğu görülmüştür. En yüksek mekanik dayanım sonucu %3 diatomit içeren harçlarda gözlenmiştir. FESEM görüntüleri sonucunda %3 diatomit ikamesi ile üretilen geopolimerin daha yoğun ve kompakt bir mikro yapı sunduğu belirlenmiştir. Ayrıca farklı senaryolara göre diatomit ikameli ve diatomit ikamesiz geopolimer harçların olumlu ve olumsuz çevresel etkileri belirlenmiştir. Sonuç olarak çevreci üretilmek istenen geopolimer harçlara çevresel çıktı olarak etki eden diatomit oranı, aktivatör oranı, aktivatör türü, kür süresi, kür sıcaklıkları ve hammaddeye ulaşım mesafesi gibi faktörlerin görece olumlu ve olumsuz sonuçları irdelenmiştir.

Anahtar Kelimeler

Geopolimer, Yaşam Döngüsü Değerlendirmesi, Uçucu Kül, Diatomit, Sürdürülebilirlik

Kaynakça

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