PERFORMANCE OPTIMIZATION OF CEMENT MORTARS WITH PARTIAL REPLACEMENT OF INDUSTRIAL WASTE SLUDGE: A RESPONSE SURFACE METHODOLOGY APPROACH

Öz

In this study, the potential use of wood-based industrial waste sludge (IWS) as a partial replacement material in cement mortars was investigated. The primary aim of the study is to evaluate the feasibility of utilizing this waste in the production of sustainable construction materials. For this purpose, mortar specimens with different substitution ratios of IWS were prepared and tested for flexural strength, and the results were modeled using Response Surface Methodology (RSM). Analysis of variance (ANOVA) revealed that cement content and curing duration had significant effects on flexural strength. The RSM model successfully predicted the experimental outcomes with a high coefficient of determination (R²> 95%), and its accuracy was verified through validation tests. Optimization results indicated that 450 kg/m³ cement and approximately 81,6 days of curing were the optimum parameters, where the experimental flexural strength was 11,60 MPa, while the RSM prediction was 11,76 MPa with an error margin of only 1,38%. Consequently, it was concluded that IWS can be considered a sustainable supplementary material at low substitution levels in cement mortars, and that RSM is an effective tool for reliable modeling and optimization of mechanical performance.

Anahtar Kelimeler

• Waste
• Sludge
• Cement
• Flexural Strength
• Optimization
• Response Surface Methodology.

ÇİMENTO HARÇLARINDA ENDÜSTRİYEL ATIK ÇAMURUNUN KISMİ İKAMESİNE YÖNELİK PERFORMANS OPTİMİZASYONU: YANIT YÜZEYİ METODOLOJİSİ YAKLAŞIMI

Öz

ÖZ Bu çalışmada, ahşap esaslı endüstriyel atık çamurunun (EAÇ) çimento harçlarında kısmi ikame malzemesi olarak kullanılabilirliği araştırılmıştır. Çalışmanın temel amacı, atık malzemenin sürdürülebilir inşaat malzemesi üretiminde değerlendirilebilirliğini ortaya koymaktır. Bu kapsamda, farklı oranlarda EAÇ ikamesi ile hazırlanan numuneler üzerinde eğilme dayanımı deneyleri gerçekleştirilmiş ve elde edilen sonuçlar Yanıt Yüzeyi Metodolojisi (YYM) kullanılarak modellenmiştir. Varyans analizi (ANOVA) sonuçları, çimento miktarı ve kür süresinin eğilme dayanımı üzerinde anlamlı etkiler gösterdiğini ortaya koymuştur. YYM modeli yüksek uyum katsayısı (R²> %95) ile deneysel sonuçları başarıyla tahmin etmiş ve model doğruluğu doğrulama deneyleri ile kanıtlanmıştır. Optimizasyon çalışmaları sonucunda, 450 kg/m³ çimento ve yaklaşık 81,6 günlük kür süresi optimum parametreler olarak belirlenmiş, bu koşullarda deneysel değer 11,60 MPa iken YYM tarafından 11,76 MPa olarak tahmin edilmiş ve hata oranı yalnızca %1,38 bulunmuştur. Sonuç olarak, EAÇ’nin düşük ikame oranlarında çimento harçlarında sürdürülebilir bir katkı malzemesi olarak değerlendirilebileceği ve YYM’nin mekanik performansın güvenilir biçimde modellenmesi ve optimizasyonunda etkili bir yöntem olduğu görülmüştür.

Anahtar Kelimeler

• Atık
• Çamur
• Çimento
• Eğilme Dayanımı
• Optimizasyon
• Yanıt Yüzey Yöntemi.

Kaynakça

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