Microwave Heating and Self-Healing Performance of Asphalt Mixtures Containing Metallic Fibres from Recycled Tyres
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View abstract on PubMed
Summary
This summary is machine-generated.Recycled metal fibres from end-of-life tyres (ELTs) do not enhance microwave heating in asphalt. Instead, aggregates primarily trigger crack healing, which improves with repeated healing cycles.
Area Of Science
- Materials Science
- Civil Engineering
- Sustainable Construction
Background
- End-of-life tyres (ELTs) present recycling challenges.
- Asphalt mixtures can benefit from enhanced self-healing properties.
- Microwave heating offers a potential method for asphalt repair.
Purpose Of The Study
- To evaluate the impact of recycled metal fibres from ELTs on asphalt's microwave heating efficiency.
- To investigate the self-healing capabilities of asphalt mixtures containing ELT fibres under microwave irradiation.
- To optimize microwave heating parameters for asphalt self-healing.
Main Methods
- Laboratory testing of four dense asphalt mixtures with varying percentages of metallic fibres (0%, 1.5%, 2.5%, 3.5%).
- Measurement of microwave heating properties of mixtures and components at different heating times (10-60s).
- Evaluation of cracking and self-healing properties after microwave exposure (30s, 40s, 50s).
Main Results
- Metallic fibres are not essential for microwave heating of asphalt; aggregates are the primary heating medium.
- The self-healing level in asphalt mixtures, with or without fibres, increases with successive healing cycles.
- Optimal microwave heating time for laboratory asphalt mixtures is 40 seconds.
Conclusions
- Aggregates play a crucial role in microwave-induced self-healing of asphalt.
- Repeated microwave healing cycles enhance the self-healing capacity of asphalt.
- A 40-second microwave heating duration is recommended for laboratory asphalt mixtures.
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