Characterization of Coarse Recycled Aggregates Produced from Concretes with Different Strength Levels

Öz

With the acceleration of Urban Renewal Program, particularly in large cities of Turkey, the problem of finding land-fills and eliminating construction waste with the least environmental pollution necessitates its value-added recycling. However, the presence of adhered weak mortar layer, comprising 20-70% of recycled concrete aggregate (RCA), limits the use of RCA or lowers its inclusion level in concrete mixtures. Within the scope of this study, limestone- and basalt-bearing RCA obtained from 6 different concrete mixtures with three different water/cement ratios (0.45, 0.60, 0.70) were prepared and their water absorption, specific gravity, dense and loose unit weight, flatness indices, Los Angeles degradation values were determined. The results showed that, increasing w/c ratio of the parent concrete increased water absorption of the resultant RCA. However, the specific gravity, unit weight, abrasion resistance and flakiness index of RCA were decreased by increasing w/c ratio of the parent concrete.

Anahtar Kelimeler

• recycled concrete aggregate
• parent concrete strength level
• water absorption
• degradation resistance
• flakiness index

Destekleyen Kurum

Scientific and Technological Research Council of Turkey (TÜBITAK)

Proje Numarası

119R037

Teşekkür

The authors would like to acknowledge the financial support provided by TÜBİTAK under grant No: 119R037.

Kaynakça

1. Asmatulu, R., & Asmatulu, E. (2011). Importance of recycling education: a curriculum development at WSU. Journal of Material Cycles and Waste Management, 13(2), 131.
2. Batman, M. (2018). Investigation of the usability of concrete test sample wastes as recycling aggregate. (Master Thesis, Atatürk University).
3. Debieb, F. Courard, L. Kenai, S. Degeimbre, R. (2010). Mechanical and durability properties of concrete using contaminated RAs. Cement and Concrete Composites, Vol. 32 (6), pp.421–426.
4. Demirel, C., Toklu, K., & Şimşek, O. (2015). Usability of recycling aggregate in concrete production and evaluation in terms of sustainability, 2nd International Sustainable Buildings Symposium.
5. Etxeberria, M. Vazquez, E. Mari, A. Barra, M. (2007). Influence of amount of recycled coarse aggregates and production process on properties of RAC. Cement and Concrete Research, Vol. 37 (5), pp.735–742.
6. Fonseca, N. De Brito, J. Evangelista, L. (2011). The influence of curing conditions on the mechanical performance of concrete made with recycled concrete waste. Cement and Concrete Composites, Vol. 33 (6), pp. 637–643.
7. Huda, S.B. Shahria Alam, M. (2015). Mechanical and freeze-thaw durability properties of RAC made with recycled coarse aggregate. Journal of Materials in Civil Engineering, Vol. 27 (10): 04015003.
8. Malešev, M., Radonjanin, V., & Broćeta, G. (2014). Properties of recycled aggregate concrete. Contemporary Materials, 5(2), 239-249.

9. Mehta, P. K. (2001). Reducing the environmental impact of concrete. Concrete international, 23(10), 61-66.
10. Mehta, P. K. (2002). Greening of the concrete industry for sustainable development. Concrete international, 24(7), 23-28.
11. Mohammed, N., Sarsam, K., & Hussien, M. (2018). The influence of recycled concrete aggregate on the properties of concrete. In MATEC Web of Conferences (Vol. 162, p. 02020). EDP Sciences.
12. Movassaghi, R. (2006). Durability of reinforced concrete incorporating recycled concrete as aggregate (RCA) (Master's thesis, University of Waterloo).
13. Nagataki, S., Gokce, A., Saeki, T., “Effects of Recycled Aggregate Characteristics on Performance Parameters of Recycled Aggregate Concrete”, Proceedings of 5th CANMET/ACI International Conference on Durability of Concrete, Barcelona, June 2012, pp. 51-71.
14. Naik, T. R., & Moriconi, G. (2005, October). Environmental-friendly durable concrete made with recycled materials for sustainable concrete construction. In International Symposium on Sustainable Development of Cement, Concrete and Concrete Structures, Toronto, Ontario, October (pp. 5-7).
15. Öztürk, M. (2005). Effects of air pollution on health in urban areas. Ministry of Environment and Forestry, Ankara / Turkey.
16. Pacheco-Torgal, F. (2013). Introduction to the recycling of construction and demolition waste (CDW). In Handbook of recycled concrete and demolition waste (pp. 1-6). Woodhead Publishing.
17. Padmini, A. K., Ramamurthy, K., & Mathews, M. S. (2009). Influence of parent concrete on the properties of recycled aggregate concrete. Construction and Building Materials, 23(2), 829-836.
18. Sivakumar, V., McKinley, J. D., & Ferguson, D. (2004). Reuse of construction waste: performance under repeated loading. Proceedings of the Institution of Civil Engineers-Geotechnical Engineering, 157(2), 91-96.
19. Tam, V. W., Soomro, M., & Evangelista, A. C. J. (2018). A review of recycled aggregate in concrete applications (2000–2017). Construction and Building Materials, 172, 272-292.
20. TS EN 1097-2 (2020), Tests for mechanical and physical properties of aggregates - Part 2:Methods for the determination of resistance to fragmentation. Turkish Standard Institute.
21. TS EN 1097-3 (1999), Tests for mechanical and physical properties of aggregates- Part 3: Determination of loose bulk density and voids. Turkish Standard Institute.
22. TS EN 1097-6 (2013), Tests for mechanical and physical properties of aggregates - Part 6: Determination of particle density and water absorption. Turkish Standard Institute.
23. TS EN 12390-3 (2019), Testing hardened concrete - Part 3: Compressive strength of test specimens. Turkish Standard Institute.
24. TS EN 933-1:2012(EN) (2012), Tests for geometrical properties of aggregates - Part 1: Determination of particle size distribution - Sieving method. Turkish Standard Institute.
25. TS EN 933-3 (2012), Tests for geometrical properties of aggregates - Part 3: Determination of particle shape - Flakiness index. Turkish Standard Institute.
26. Verian, K. P., Ashraf, W., & Cao, Y. (2018). Properties of recycled concrete aggregate and their influence in new concrete production. Resources, Conservation and Recycling, 133, 30-49.
27. Volz, J.S., Khayat, K.H., Arezoumandi, M., Drury, J., Sadati, S., Smith, A. and Steele, A., (2014). Recycled Concrete Aggregate (RCA) for Infrastructure Elements, Final Report Prepared for Missouri Department of Transportation.