Omeed Adwal Ali ALİ, Oğuzhan ÖZTÜRK, Ülkü Sultan KESKİN, Cengiz ATİŞ

Farklı Hacimlerdeki Uçucu Külün Isı İle Kürlenen Hava Sürükleyici Katkılı Çimento Harçlarına Etkisi

Uçucu külün doğası karbon kalıntısı içermektedir ve yüzey aktif maddeler ile karbon kalıntısı arasındaki etkileşim çimento esaslı malzemelerin performansı için sorun teşkil etmektedir. Buna ek olarak, beton gibi malzemelerin ısı ile kür edilmesi bu tip mikro yapısal bozulmayı daha açık hale getirebilir. Bu konuyu daha fazla detaylandırmak üzere, hava sürükleyici katkı maddesinin, farklı hacimlerde uçucu kül içeren ısı kürü ile kür edilmiş çimento harçları üzerindeki etkisi deneysel bir çalışma ile incelenmiştir. Uçucu kül içeren hava sürükleyici katkılı çimento harçlarının mekanik özellikleri farklı yaşlarda değerlendirilmiştir. Karşılaştırmalı araştırma ayrıca mikro yapısal analizlerle de gerçekleştirilmiştir. Karbon esaslı malzemelerin ve hava sürükleyici katkı maddesinin etkileşimi mekanik ve mikro yapısal bulgular dikkate alınarak ayrıntılı olarak tartışılmıştır. Sonuçlar, hava sürükleyici katkı maddesi ile toplam bağlayıcı malzeme ağırlığınca %25 uçucu kül kullanılmasının, hava sürükleyici katkı içermeyen ısı ile kür edilmiş çimento harçlarına kıyasla olumlu olduğunu göstermektedir. Ancak ısı ile kür edilmiş ve hava sürükleyici katkı maddesi içeren çimento esaslı harçlarda uçucu külün %55’ten fazla kullanımı ise tavsiye edilmemektedir.

Anahtar Kelimeler:

Hava sürükleyici katkı, Uçucu kül, Isı kürü, Mekanik özellikler

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