Kalsine edilmiş zeolit esaslı geopolimerlerin basınç dayanımına mineral katkı olarak cürufun etkisi

Year 2023, Volume: 13 Issue: 4, 939 - 948, 15.10.2023

Sevgi Özen

https://doi.org/10.17714/gumusfenbil.1297172

Abstract

Geopolimerler, yeşil bağlayıcı malzeme olarak adlandırılan ve başlangıç hammaddeleri olarak doğal veya atık malzemeleri içeren yapı malzemeleridir. İnşaat sektöründeki potansiyel uygulamaları bilimsel olarak oldukça araştırılmış olmasına rağmen, doğal malzeme esaslı geopolimerlerin yaygın kullanımları sınırlı kalmıştır. Bunun temel nedeni, doğal malzeme esaslı geopolimerlerin düşük erken basınç dayanım değerlerine sahip olmaları ve dolayısıyla oda koşullarında erken dönemde yeterli kürleme sağlayamamalarıdır. Bu sorunu aşmak için öncelikle klinoptilolit içeren tüf 900°C’de kalsinasyon işlemine maruz bırakılmış, ardından mineral katkı olarak yüksek fırın cürufu eklenmiştir. Elde edilen geopolimerlerin mukavemet gelişimi, basınç dayanım analizleri kullanılarak saptanmıştır. Mikro yapısal incelemeler, XRD ve SEM analizleri kullanılarak gerçekleştirilmiştir. Yapılan analizler sonucunda, kalsinasyon işleminin erken dönemde mukavemeti artırdığı ve cüruf katkısıyla basınç dayanımının daha da iyileştiği belirlenmiştir. Analiz sonuçlarına göre 900°C’de kalsine edilmiş yüksek fırın cürufu katkılı geopolimerin 28 günlük basınç dayanım değeri 46 MPa olarak saptanmıştır. XRD analizi sonucunda, malzemenin kalsinasyon başarısının amorf faz ile ilişkili olduğu tespit edilmiştir. Ayrıca, SEM/EDX analizi ile geopolimer jelin en iyi cüruf katkılı geopolimerde geliştiği ortaya konulmuştur.

Keywords

Cüruf, Geopolimer, Kalsinasyon, Klinoptilolit

The effect of slag as mineral admixture on the compressive strength of calcined zeolite-based geopolymer

Abstract

Geopolymers, referred to as green binder materials, are construction materials that incorporate natural or waste materials. Despite extensive scientific research on their potential applications in the construction sector, widespread utilization of natural material-based geopolymers has remained limited. The primary reason for this limitation is their low early compressive strength values, which consequently hinder achieving adequate curing under ambient conditions. To overcome this challenge, the tuff containing clinoptilolite was subjected to a calcination process at 900°C, followed by the addition of blast furnace slag as a mineral admixture. The strength development of the synthesized geopolymers was compared through compressive strength analyses. Microstructural examinations were conducted using XRD and SEM analyses. The analysis results demonstrated that the calcination process enhanced the early strength development, and the addition of slag further improved the compressive strength. Asa result of XRD analysis it has been determined that the success of material calcination is associated with the amorphous phase. According to the analysis results, the compressive strength of the high blast furnace slag blended geopolymer, calcinated at 900°C, was determined as 46 MPa after 28 days. Moreover, the SEM/EDX analysis revealed that the geopolimer gel exhibited the best performance in the presence of slag additives.

Keywords

Slag, Geopolymer, Calcination, Clinoptilolite

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