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Time-Dependent Shrinkage Model for Recycled Fine Aggregate Thermal Insulation Concrete
Xuhang Zang1, Pinghua Zhu1, Chunhong Chen1
1Changzhou City Key Laboratory of Building Energy-Saving Technology, Department of Civil Engineering, Changzhou University, Changzhou 213164, China.
Materials (Basel, Switzerland)
|October 13, 2021
Summary
Recycled aggregate thermal insulation concrete (RATIC) using waste concrete or clay brick aggregates showed increased shrinkage. Waste clay brick aggregate (RFA2) offered optimal mechanical properties and reduced shrinkage compared to waste concrete aggregate (RFA1).
Area of Science:
- Construction Materials Science
- Sustainable Building Materials
- Concrete Technology
Background:
- Developing sustainable building materials is crucial for reducing construction waste.
- Recycled aggregates offer a viable alternative to natural aggregates in concrete production.
- Thermal insulation concrete (TIC) requires specific properties for energy-efficient buildings.
Purpose of the Study:
- To investigate the shrinkage performance of recycled aggregate thermal insulation concrete (RATIC) with added glazed hollow beads (GHB).
- To evaluate the mechanical properties and thermal insulation performance of RATIC.
- To propose and validate a time-dependent shrinkage model for RATIC.
Main Methods:
- Two types of recycled fine aggregate (RFA) from waste concrete (RFA1) and waste clay brick (RFA2) were used to replace natural fine aggregate.
- The influence of RFA replacement ratio and GHB addition on RATIC properties was studied.
- A time-dependent shrinkage model was developed and validated against experimental data.
Main Results:
- RFA2 improved mechanical properties of RATIC, with 75% replacement being optimal.
- Added RFA decreased thermal conductivity, while increasing total shrinkage strain.
- RATIC with RFA2 exhibited lower total shrinkage strain than RATIC with RFA1, especially at higher replacement ratios.
Conclusions:
- Recycled aggregates can be effectively used in thermal insulation concrete, with RFA2 showing superior performance.
- A validated time-dependent shrinkage model can predict RATIC behavior.
- Optimizing RFA type and replacement ratio is key to balancing mechanical, thermal, and shrinkage properties in RATIC.
Keywords:
glazed hollow beadrecycled fine aggregaterecycled fine aggregate thermal insulation concreteshrinkage developmenttime-dependent shrinkage modelMore Related Videos
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