Çimentolu Macun Dolgunun Dayanım ve Mikroyapı Özellikleri; C-Sınıfı Uçucu Külün Etkisi

Abstract

Bu çalışmada, sülfürlü atık yerine ağırlıkça %5-15 oranında C-sınıfı uçucu kül (UK) ikamesinin çimentolu macun dolgunun (ÇMD) dayanım ve mikroyapı özelliklerine etkisi incelenmiştir. Bu kapsamda kontrol numuneleri %8,5 bağlayıcı oranında, UK içeren dolgu numuneleri ise %7,5 bağlayıcı oranında hazırlanmıştır. Bu numuneler, tek eksenli basınç dayanımı (TEBD) ve porozite (MIP) testlerine tabi tutulmuştur. Bulgular değerlendirildiğinde, UK içeren tüm ÇMD numunelerinin kontrol numunelerine kıyasla 1,18-3,16 kat daha yüksek TEBD ürettiği gözlemlenmiştir. Dolgunun stabilite (TEBD≥1,0MPa) kriterini tüm numuneler sağlarken, tavan (zemin) tahkimatı (TEBD≥5,0MPa) kriterini sadece %15 UK’lı numuneler sağlamıştır. Porozite (MIP) gelişimleri incelendiğinde, UK ikamesi numunelerin mikroyapı özelliklerini daha fazla iyileştirmiştir. Elde edilen sonuçlardan, C-sınıfı UK kullanımının ÇMD’nin dayanım, duraylılık ve mikroyapı özelliklerinin iyileştirilmesinde oldukça faydalı olduğu sonucuna varılmıştır.

Keywords

• C-sınıfı Uçucu Kül,Sülfürlü Atık,Tek Eksenli Basınç Dayanımı,Mikroyapı,Çimentolu Macun Dolgu

Strength and Microstructure Properties of Cemented Paste Backfill; Effect of Class-C Fly Ash

Abstract

In this study, the effect of Class-C Fly ash (FA) as partial replacement (5-15% by weight) to sulphide tailings on the strength and microstructure properties of cemented paste backfill (CPB) was examined. Within this scope, CPB samples of control were prepared at 8.5 wt.% binder dosage while the other samples containing FA were prepared at 7.5 wt.% binder dosage. These samples were subjected to uniaxial compressive strength (UCS) and porosity (MIP) tests. Findings revealed that all CPB samples containing FA produced notably higher (1.18-3.16 fold) UCSs than control samples. All CPB samples ensured the stability criterion for backfill material (UCS≥1.0MPa), whilst, only the CPB samples containing 15 wt.% FA exceeded the roof (ground) support criterion (UCS≥5.0MPa). When the developments of porosity (MIP) were investigated, the partial replacement of sulphide tailings with FA enhanced the microstructure properties of CPB samples. These results suggest that the utilization of Class-C Fly ash (FA) as partial replacement to sulphide tailings is highly beneficial for the improvement of the strength, durability and microstructure properties of CPB.

Keywords

• Class-C Fly Ash,Sulphide Tailings,Uniaxial Compressive Strength,Microstructure,Cemented Paste Backfill

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