NANO SİLİKA KÜR UYGULAMASININ ÇİMENTO BAĞLAYICILI KOMPOZİTLERİN DONMA-ÇÖZÜLME DİRENCİ ÜZERİNE ETKİSİNİN ARAŞTIRILMASI

Bu çalışmada nano silica solüsyonunda kür etkisine maruz bırakılan çimento bağlayıcılı kompozitlerin (ECC), donma-çözülme döngüleri gibi ağır çevresel koşullar altında gösterdikleri direnç araştırılmıştır. Bu amaçla iki farklı tip uçucu kül iki farklı oranda kullanılarak dört farklı karışım olarak hazırlanan ECC numuneleri, ASTM C666 ProsedürA’ya uygun olarak 300 donma-çözülme döngüsüne maruz bırakılmıştır. Numunelerin mekanik özelliklerindeki değişimler basınç ve eğilme testleri ile, fiziksel özelliklerindeki değişimler ise, 30 çevrimde bir ağırlıklarının ölçülmesi ile belirlenmiştir. Çalışma neticesinde elde edilen sonuçlar, çimento bağlayıcılı kompozitlerde nano silica (NS) kür uygulamasının, zorlayıcı çevresel koşullar altında numunelerin dayanım ve dayanıklılık gibi özelliklerinde suda kür uygulamasına göre kayda değer artışlar sergilediğini göstermiştir.

Anahtar Kelimeler:

çimento bağlayıcılı kompozitler, donma-çözülme etkileri, uçucu kül, mekanik ve fiziksel özellikler

INVESTIGATION OF THE EFFECT OF NANO-SILICA CURING ON THE FREEZE-THAW RESISTANCE OF CEMENTITIOUS COMPOSITES

In this study, the resistance of cementitious composites (ECC) exposed to the curing effect in nano-silica solution under heavy environmental conditions such as freeze-thaw cycles is investigated. For this purpose, ECC samples prepared as four different mixtures using two different types of fly ash in two different ratios were subjected to 300 freeze-thaw cycles in accordance with ASTM C666 Procedure A.The changes in the mechanical properties of the samples were tested with compressive and bending tests, changes in the physical properties of the samples were determined by measuring their weights in every 30 cycles. The results of the study showed that nano-silica curing in cementitious composites exhibit remarkable increases in the properties such as strength and durability of the samples even under challenging environmental conditions compared to water curing.

Keywords:

Cementitious composites, freez-thaw effects, flyash, mechanical and physical properties,

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