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The Simple Mix Design Method and Confined Behavior Analysis for Recycled Aggregate Concrete
Chong Rong1,2,3, Jing Ma2, Qingxuan Shi1,2,3
1State Key Laboratory of Green Building, Western China of Xian University of Architecture & Technology, Xi'an 710055, China.
Materials (Basel, Switzerland)
|July 2, 2021
Summary
This study introduces a simple method for designing recycled aggregate concrete (RAC). Confining RAC within steel or GFRP tubes enhances its mechanical properties, offering sustainable construction solutions.
Area of Science:
- Civil Engineering
- Materials Science
- Sustainable Construction
Background:
- Construction waste, specifically waste concrete, can be repurposed into recycled aggregate concrete (RAC).
- Existing RAC mix design methods are complex, and RAC often exhibits reduced mechanical properties compared to ordinary concrete.
- Sustainable development in building construction necessitates efficient utilization of recycled materials.
Purpose of the Study:
- To develop a simplified mix design methodology for recycled aggregate concrete (RAC).
- To investigate the behavior and mechanical properties of RAC confined within steel tubes (RCFST) and glass fiber reinforced polymer (GFRP) tubes (RCFST).
- To evaluate the effectiveness of confinement on the performance of RAC columns.
Main Methods:
- Utilized orthogonal and single-factor tests to establish a simple mix design for RAC.
- Conducted comprehensive experimental studies on RCFST and RCFST specimens.
- Analyzed the mechanical behavior of confined RAC through experimental data.
Main Results:
- The proposed mix design method efficiently produces RAC with stable strength grades.
- Both steel and GFRP tubes provide significant confinement, enhancing the mechanical behavior of the core RAC.
- Confined RAC in steel tubes exhibited properties similar to passively confined concrete, while GFRP-confined RAC behaved like actively confined concrete.
Conclusions:
- The developed mix design method is effective for promptly and efficiently producing various strength grades of RAC.
- Steel and GFRP tubes effectively confine RAC, improving its performance in structural applications.
- The findings provide valuable insights for designing with RAC and serve as a basis for further research on confined RAC.
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