期刊
CEMENT & CONCRETE COMPOSITES
卷 124, 期 -, 页码 -出版社
ELSEVIER SCI LTD
DOI: 10.1016/j.cemconcomp.2021.104251
关键词
Recycled aggregate concrete; Microbial induced carbonate precipitation; Compressive strength; Steel corrosion; Cracks propagation; ITZs microhardness
资金
- Key Technology Research and Development Program of Zhejiang Province [2020C04013]
The study tested the physical properties of recycled coarse aggregate (RCA) before and after microbial induced carbonate precipitation (MICP) modification, and investigated the effects of MICP modification on the mechanical and durability properties of concrete specimens. SEM observation and ITZs microhardness test were conducted to reveal the micro mechanism of improvement due to the MICP modification, showing that the modified RCA exhibited improved properties and the concrete specimens with modified RCA exhibited higher compressive strength and steel corrosion resistance.
The mechanical and durability properties of recycled aggregate concrete (RAC) are generally inferior to conventional concrete due to the old mortar attached to the surface of original aggregate, which induces more complicated interfacial transition zones (ITZs) in the RAC. The microbial induced carbonate precipitation (MICP) modification is a novel and environmentally-friendly method to improve the ITZs and old mortar in RAC. In this study, the physical properties of recycled coarse aggregate (RCA) before and after the MICP modification were tested; then, the effects of the MICP modification on the mechanical and durability properties of the concrete with the RCA and the modified RCA were investigated. The SEM observation and ITZs microhardness test were conducted to reveal the micro mechanism of improvement due to the MICP modification. The results show that the modified RCA exhibits lower water absorption and apparent density; the concrete specimens with the modified RCA exhibits higher compressive strength, higher steel corrosion resistance, and less corrosion-induced cracks, which can be explained by the enhanced microhardness of ITZ between the old and new mortar.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据