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Utilization of waste Cappadocia earth as a natural pozzolan in alkali activation: A parametric study    
Yazarlar (3)
Şerife Özata
Türkiye
Büşra Aktürk
İstanbul Bilgi Üniversitesi, Türkiye
Nabi Yüzer
Yıldız Teknik Üniversitesi, Türkiye
Devamını Göster
Özet
This study presents the investigation of the possible use of rock-cut carving waste earth in Cappadocia as a precursor in alkali activation. The Cappadocia waste earth was activated by sodium hydroxide (NH) and sodium silicate (WG). In addition, slaked lime (CH) was substituted as a calcium resource. The compressive strength development was determined and the reaction mechanisms were investigated through X-ray diffraction and Fourier transform infrared spectroscopy. It was found that different strength levels can be obtained, depending on the activator type and CH-substitution ratio. While WG-activated mixes presented higher early age values, NH-activated mixes presented higher values at further ages, i.e., ~17 MPa at 28 days. The CH substitution enhanced the compressive strength for both early and further ages, attributing to the available Ca2+ ions resulting in the formation of C-A-S-H gel. The XRD results showed that silicates group minerals prominent in control mixes, while C-A-S-H-like gel was the primary phase in CH-substituted mixes. N-A-S-H and other hydrated compounds were found in all mixes, responsible for strength increment. Moreover, secondary electron microscope images revealed a denser structure in WG-activated mixes. Results of energy dispersive spectroscopy and X-ray diffractions corroborated hydration products and alkali activation. The obtained results of this study depict that alkali-activated Cappadocia earth can be a feasible and alternative sustainable binder to be used as a structural material.
Anahtar Kelimeler
Makale Türü Özgün Makale
Makale Alt Türü SSCI, AHCI, SCI, SCI-Exp dergilerinde yayımlanan tam makale
Dergi Adı Elsevier BV
Dergi ISSN 0950-0618
Dergi Tarandığı Indeksler SCI-Expanded
Dergi Grubu Q1
Makale Dili Türkçe
Basım Tarihi 04-2022
Cilt No 329
Doi Numarası 10.1016/j.conbuildmat.2022.127192
Makale Linki http://dx.doi.org/10.1016/j.conbuildmat.2022.127192