Abstract
Cool road pavements contribute to mitigating urban heat islands. To evaluate the heat balance in paved surfaces and to select appropriate road construction materials that help suppress heat islands, an accurate understanding of heat transport parameters such as thermal conductivity (λ) and heat capacity (HC) is important. Recycled aggregates from construction and demolition waste, including scrap construction materials and industrial by-products, are often used for road construction; however, λ and HC of recycled aggregates especially for roadbeds are not fully understood. This study involved a series of laboratory tests to measure λ and HC of recycled concrete and clay brick aggregates (<40 mm) and their mixtures with autoclaved aerated concrete grains (<2 mm) under varied moisture conditions. The measured λ and HC increased with increasing volumetric water content (θ). Closed-form models for estimating λ(θ) were proposed using normalized thermal conductivity (λe) and effective saturation (Se). The new λe(Se) models performed well for the measured data compared to previously proposed models and would be useful to evaluate λ of recycled aggregates for roadbed materials.
Original language | English |
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Article number | 2417 |
Journal | Sustainability (Switzerland) |
Volume | 14 |
Issue number | 4 |
Number of pages | 22 |
ISSN | 2071-1050 |
DOIs | |
Publication status | Published - 1 Feb 2022 |
Bibliographical note
Funding: This research was supported by the project of Japan Science and Technology Agency (JST), Japan International Cooperation Agency (JICA) on Science, and Technology Research Partnership for Sustainable Development (SATREPS) (no. JPMJSA1701).Publisher Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland.
This article belongs to the Special Issue Environmentally Sound Waste Management and Zero Waste Principles.
Keywords
- Autoclaved aerated concrete (AAC)
- Construction and demolition waste (CDW)
- Heat capacity
- Recycled aggregates
- Thermal conductivity
- Urban heat islands