Tüf Esaslı Alkali-Aktive Edilmiş Hamurların Mekanik ve Mikro Yapısal Özelliklerine Farklı Orijinli NaOH'ın Etkileri

Öz

Türkiye, mermer ve volkanik tüf gibi doğal taşlar açısından zengin yataklara sahiptir. İnşaat sektöründe genellikle kaplama karosu olarak kullanılırlar. Böylece hem taş ocaklarında hem de fabrikalarda üretim süreçlerinde yaklaşık %70'e yakın atık ortaya çıkmaktadır. Bu atıklar, büyük ve mikro ölçekte katı hal çevre kirliliğine yol açmaktadır. Alkali ile aktive olan malzemeler (AAM'ler), bu atıkları tuğla üretimi gibi bazı üretimlerde kullanmanın en etkili yoludur ve ayrıca AAM'lerin üretiminde NaOH en yaygın alkali aktivatördür. Ancak, NaOH imalat sektörü dünyada çok büyüktür ve farklı teknikler kullanan birçok marka bulunmaktadır. Burada iki farklı ülkeden temin edilmiş granül halde NaOH alkali aktivatör olarak 5 Molar ve 10 Molar konsantrasyonlarda çözelti ile tüf ve traverten içeren alkali ile aktive edilmiş hamurlar (AAP) üretilmiştir. Tüm AAP'ler laboratuvar koşullarında 22±2 oC ve %35 R.H'de kürlenmiştir. Kür periyodunun 7., 28. ve 90. günlerinde basınç dayanımı testleri yapılmıştır. Aynı zamanda 90 gün yaşındaki AAP’lerde mikro yapı incelemeleri de gerçekleştirilmiştir. Bu çalışma sonucunda farklı ülkelerden NaOH hem mekanik hem de mikroyapısal özelliklere etki etmektedir. En yüksek basınç dayanımı 46 MPa olarak elde edilmiştir. 5 molar konsantrasyonla hazırlanan AAP'lerin çoğunlukla 28. günden sonra yeterince stabil olmadığı gözlendi.

Anahtar Kelimeler

• Traverten
• volkanik tüf
• alkali aktifleştirilmiş hamur
• basınç dayanımı
• mikro yapı

The Effects of Different Origins NaOH on the Mechanical and Microstructural Properties of Tuff-Based Alkali-Activated Pastes

Öz

Turkey has rich deposits in natural stones such as marble and volcanic tuff. These are commonly used as cladding tiles in the construction sector. So, almost 70% wastes are aroused during the production processes of both quarries and factories. These wastes give rise to solid state environmental pollutions in large and micro scales. Alkaliactivation method (AAM) is the most effective way to use these wastes in productions like brick manufacturing, and also NaOH is the most common alkali-activator in the production of AAMs. However, the NaOH manufacturing sector is very huge in the world; and there are lots of brands which use different technics. In here, alkali-activated pastes (AAP) contained tuff and travertine were produced with using NaOH as an alkali activator from two different countries in the solutions with 5 Molar and 10 Molar concentrations. All AAPs were cured in laboratory condition at 22±2 oC and 35% R.H. The compressive strength tests were carried out on the 7th, 28th and 90th days of curing period. Moreover, microstructural investigations were performed on AAPs at the age of 90 day. As a result of this study, NaOH from different countries effects the mechanical and microstructural properties. The highest compressive strength is obtained as 46 MPa. It is observed that the AAPs prepared with 5 molar concentration aren’t stable sufficiently after 28th days mostly.

Anahtar Kelimeler

• Travertine
• volcanic tuff
• alkali-activated paste
• compressive strength
• microstructure

Kaynakça

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