Mechanical activation of end-of-life building materials: grinding efficiency and potential for valorization

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İLCAN H.

Journal of Structural Engineering & Applied Mechanics (Online), cilt.9, sa.1, ss.1-8, 2026 (ESCI, TRDizin)

Özet

Optimized grinding enhances material reactivity while reducing processing time and energy demand, supporting more sustainable and cost-effective construction. In this context, construction and demolition waste (CDW), widely landfilled due to its low reactivity, represents a promising candidate for upgrading. Accordingly, this study investigates the valorization potential of CDW-derived concrete waste (CW) as a value-added raw material. Vertical stirred mill was employed to investigate influences of grinding parameters, media filling ratio (MF = 50% and 70%) and grinding duration (5 min and 30 min), on features of CW. Particle size distribution (PSD) and specific surface area (SSA) were tested, while flow table and compressive strength tests were performed to investigate effect of CW on cementitious systems. Grinding reduced the median particle size (D50) from approximately 197 µm to 14–34 µm and increased the SSA by nearly 3–4 times. Replacing 20% of cement with untreated CW led to a significant reduction in workability and compressive strength, whereas ground CW mixtures exhibited improved mechanical performance. Although all CW mixtures remained below the reference, grinding enhanced compressive strength substantially compared to untreated CW. The effect of prolonged grinding varied with media filling ratio; while extended milling at 50% filling did not enhance performance, it contributed positively at 70%. The findings demonstrate that strength development is governed not only by fineness but also by agglomeration behavior and effective particle packing within the matrix.