Alkali ile Aktive Edilmiş Cüruf Harçlarının Yangın Direnci

Çalışmada, alkali ile aktive edilmiş cüruf harçlarının yüksek sıcaklıklara maruz bırakılması sonrasındaki eğilme ve basınç mukavemetleri Portland çimentolu kontrol harcı ile kıyaslanmıştır. Öğütülmüş granüle yüksek fırın cürufunun, ağırlıkça %100 oranında çimento ile yer değiştirilerek kullanıldığı çalışmada, harç karışımlarının su/bağlayıcı oranı 0,5 ve kum/bağlayıcı oranı 3,0 olmuştur. Cürufun aktivasyonunda, ağırlıkça cüruf miktarına göre %4, %6 ve %8 Na konsantrasyonlarındaki sıvı sodyum silikattan yararlanılmış olup, karışımlar içerisinde 0,75, 1,0, 1,25 ve 1,5 gibi farklı silikat modülleri (Ms=SiO2/Na2O) elde edebilmek amacıyla sıvı sodyum silikat, sodyum hidroksit ile beraber karıştırılmıştır. Ulaşılan bulgulardan, alkali ile aktive edilmiş cüruf harçlarının yangına karşı direncinin Portland çimentolu kontrol harcından daha iyi olduğu ve harçların yüksek sıcaklıklara karşı direncinin, uygulanan soğutma metodu ile sıcaklık seviyesine bağlı olduğu görülmüştür.

The Fire Resistance of Alkali-Activated Slag Mortars

In this study, the compressive and flexural strength of alkali activated slag mortars subjected to high temperatures were investigated, and the results obtained from the tests were compared with the control mortar. In the experiments, sand and water quantities were kept constant throughout the tests. Water/binder and sand/binder ratios were 0.5 and 3.0, respectively. Ground granulated blast furnace slag was used at 100% replacement by weight of cement in the tests. For slag activation, liquid sodium silicate at 4%, 6% and 8% Na dosages was used, and liquid sodium silicate and sodium hydroxide were blended to obtain 0.75, 1.00, 1.25 and 1.50 modulus ratio of SiO2/Na2O. The findings showed that the fire resistance of alkali activated slag mortars were better than mortar with Portland cement. Additionally, the resistance of mortars to high-temperatures seemed to be dependent on temperature level and the cooling method.

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