Concrete truck pouring concrete in a bin.

Mechanical Properties of Recycled Concrete Aggregate for Medium-Quality Structural Concrete

With increased attention to the construction industry’s environmental impact, research has turned to investigating ways to decrease these effects. Concrete production, use and sustainability are areas where researchers seek to lessen the construction industry’s environmental impact.

Abstract

The use of recycled coarse aggregate (RCA) has a high potential to significantly reduce the environmental impact of construction projects as well as the cost of construction materials. Reusing RCA in concrete mixes as a partial or full replacement of fine or coarse aggregate would be a more effective action in supporting and protecting the environment and reducing construction and demolition waste. This research reports the evaluation of medium-quality concrete properties incorporating RCA. Concrete cylinders, prisms, and cubes, as well as reinforced concrete (RC) beams, are prepared with different replacements of the RCA (25%, 50%, 75%, and 100%). The workability, mechanical properties, and reinforcement bond of cured concrete are examined at different ages. Moreover, microscopic analysis for the recycled concrete is presented to investigate the bond between the cement paste, the used aggregates, and the interfacial transition zone (ITZ). The effect of the stainless-steel fibers, crumb rubber, and CFRP laminates on the mechanical properties of recycled concrete aggregate is explored.

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Researchers

Ayman Elzohairy, Ph.D., P.E. Associate Professor

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