Open Access

ARTICLE

Repair of Second-Generation Recycled Fine Aggregate of Waste Concrete from Freeze-Thaw Environment by Carbonation Treatment

by Jie Huang^*, Rongbin Jiang, Xiaobo Sun, Yingyong Shuai

School of Building Engineering, Taizhou Polytechnic College, Taizhou, 225300, China

* Corresponding Author: Jie Huang. Email:

Journal of Renewable Materials 2024, 12(1), 187-201. https://doi.org/10.32604/jrm.2023.044232

Received 24 July 2023; Accepted 25 September 2023; Issue published 23 January 2024

Abstract

The reuse of waste recycled concrete from harsh environments has become a research hotspot in the field of construction. This study investigated the repair effect of carbonation treatment on second-generation recycled fine aggregate (SRFA) obtained from recycled fine aggregate concrete (RFAC) subjected to freeze-thaw (FT) cycles. Before and after carbonation, the properties of SRFA were evaluated. Carbonated second-generation recycled fine aggregate (CSRFA) at five substitution rates (0%, 25%, 50%, 75%, 100%) to replace SRFA was used to prepare carbonated second-generation recycled fine aggregate concrete (CSRFAC). The water absorption, porosity and mechanical properties of CSRFAC were tested, and its frost-resisting durability was evaluated. The results showed after carbonation treatment, the physical properties of SRFA was improved and met the requirements of II aggregate. The micro-hardness of the interfacial transition zone and attached mortar in CSRFA was 50.5% and 31.2% higher than that in SRFA, respectively. With the increase of CSRFA replacement rate, the water absorption and porosity of CSRFAC gradually decreased, and the mechanical properties and frost resistance of CSRFAC were gradually improved. Carbonation treatment effectively repairs the damage of SRFA caused by FT cycles and improves its application potential.

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Keywords

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