PSI - Issue 81

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ScienceDirect

Procedia Structural Integrity 81 (2026) 78–83

© 2026 The Authors. Copy from the contract: Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of DMDP 2025 organizers Keywords: recycled concrete, pressed composites, concrete waste powder, hardening, construction materials 1. Introduction As a result of military actions on the territory of Ukraine, a large number of civil and transport infrastructure facilities have been destroyed or damaged. Most of them cannot be restored and require demolition, while the resulting construction waste, mainly in the form of concrete debris, must be disposed of. The rational reuse of concrete debris meets the needs of the sustainable development program and reduces the carbon footprint (Kaptan et al. (2024)). As is well known, in global practice concrete waste is mainly used as a replacement for traditional natural aggregates (mostly coarse aggregate, less often sand) for the production of normal-weight concrete (Kaptan et al. (2024); Kwon et al. (2015)). This approach has significant environmental importance, as it contributes to the efficient utilization of large amounts of materials generated during building demolition. During the crushing of concrete debris for the production of coarse aggregate, a considerable amount of fine particles is formed. These particles are usually separated mechanically by sieves or collected by aspiration systems, settling in cyclones and bag filters. Their mass fraction is about 10 – 20% of the total weight of the debris (Kwon et al. (2015). The dispersed fraction consists mainly of partially unhydrated cement, hardened cement paste, as well as sand and stone aggregate. Due to its pronounced filler effect and certain pozzolanic activity (Wang et al. (2020); Zhang et al. (2020)), the use of dispersed concrete powder in cement-based composites has become the subject of numerous scientific studies. Abstract This study explores the potential of fine recycled concrete powder as a raw material for pressed building composites. Four types of waste concrete, differing in age, strength, and cement content, were tested under 20 MPa compaction. Specimens from younger, cement-rich waste achieved the highest strength (13.4 MPa at 28 days) and density (1.62 g/cm³), with softening coefficients around 0.9, indicating good water resistance. Humid curing produced the best results, while air drying and water immersion were less effective. Strength correlated with alite and Ca(OH) ₂ content. A simple pH test is proposed to assess the suitability of waste for pressed composites. VIII International Conference “In - service Damage of Materials: Diagnostics and Prediction“ (DMDP 2025) Performance of Pressed Materials Containing Recycled Concrete Powder Oleh Bordiuzhenko a, *, Leonid Dvorkin a , Ruslan Makarenko a , Oleksii Stepanets a , Mykola Skrypnyk a a National University of Water and Environmental Engineering, Soborna 11, 33000 Rivne, Ukraine

* Corresponding author. Tel.: +38-067-528-73-31 E-mail address: o.m.bordiuzhenko@nuwm.edu.ua

2452-3216 © 2026 The Authors. Copy from the contract: Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of DMDP 2025 organizers 10.1016/j.prostr.2026.03.014