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Alkalilerle Aktive Edilen Taban Küllü Hafif Harç Üretimi

Çalışmada Termik Santral taban külünün (TK) alkalilerle aktive edilerek hafif harç üretiminde kullanılması amaçlanmıştır. Bu amaçla öğütülmüş TK sodyum hidroksit (SH) ve sodyum silikat (SS) alkali çözeltileri kullanılarak 4x4x16 cm boyutlarında çimentosuz harç karışımları üretilmiştir. Numunelere 20 saat 75 oC’de etüvde veya laboratuvarda 20 oC’de havada kür olmak üzere iki farklı kür uygulanmıştır. 1, 7 ve 28. günlerde numunelerin birim ağırlık, ultrases geçiş hızı ve basınç dayanımları belirlenmiştir. En uygun numunenin birim ağırlığı 1,59 kg/dm3 ve basınç dayanımı 18,51 MPa, 80 donma-çözülme çevrimi sonucu dayanım kaybı % 11,5 olarak bulunmuş ve numune 400 °C’ye kadar termal stabilitesini korumuştur.

Anahtar Kelimeler:

Alkali aktivasyon, Taban külü, Harç, Dayanım, Dayanıklılık.

Production Of Alkali Activated Lightweight Bottom Ash Mortar

In this study it is attempted to use alkali activated thermal power plant bottom ash (BA) in the production of lightweight mortar. Cement-free 4x4x16 cm mortar specimens were produced using grinded BA, alkali mixtures of sodium hydroxide (SH) and sodium silicate (SS). Two different curing types of 20 h curing at 75 ºC oven and then air curing at 20 oC air or air curing at 20 oC were carried on the specimens. Unit weight, ultrasound pulse velocity and compressive strengths of the specimens were determined on 1, 7 and 28. days. Average values of the unit weight and compressive strength for the best specimen were 1,59 kg/dm3 and 18,51 MPa respectively. The compressive strength loss of the specimen was only 11,5% after 80 freeze-thaw cycles, and the specimen possessed superior thermal stability up to 400 °C.

Keywords:

Alkali activation, Bottom ash, Mortar, Strength, Durability.,

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