Recycled Aggregate: A Viable Solution for Sustainable Concrete Production

Area of Science:

• Civil Engineering
• Environmental Science
• Materials Science

Background:

• Construction and demolition activities generate substantial waste (4.5 billion tons/year) and consume vast natural resources (32 billion tons of natural aggregate annually).
• Utilizing recycled aggregate (RA) from construction and demolition waste (C&DW) and other waste streams offers a sustainable alternative to natural aggregate (NA).

Purpose of the Study:

• To review the application of RA in concrete production.
• To identify challenges and future prospects for RA utilization in concrete.
• To explore strategies for mitigating performance reductions associated with RA.

Main Methods:

• Literature review on the use of recycled aggregate in concrete.
• Analysis of performance data comparing concrete with RA and NA.
• Identification of processing and standardization challenges.

Main Results:

• Recycled aggregate generally reduces concrete's fresh and hardened performance compared to natural aggregate.
• Performance reductions are often negligible at RA replacement levels up to 30%.
• Efficient processing and international standardization are crucial for wider RA adoption.

Conclusions:

• Recycled aggregate is a viable material for concrete production, offering environmental benefits.
• Strategies exist to mitigate performance decrements, making RA suitable for many applications.
• Further advancements in RA processing technology and standardization are necessary to maximize its potential in sustainable construction.