Abstract
Using recycled powders from solid waste is accepted as an effective strategy to realize the sustainable development of the construction industry. In our study, the cement was substituted by two kinds of recycled powders, i.e., spontaneous combustion gangue powder (SCGP) and recycled concrete powder (RCP), with a certain replacement ratio of 30%. The experimental variables were mainly the type of replacement powder (e.g., SCGP, RCP, and SCGP + RCP) and the grinding time of RCP (e.g., 25 min, 50 min, and 75 min). The fundamental properties, including mechanical properties, long-term properties, and carbon emission, were analyzed for all the mortar mixtures. Experimental results indicate that incorporation of RCP contributes to enhancing the toughness and dry shrinkage resistance of eco-efficient mortar, while SCGP positively affects the compressive strength and chloride resistance. The grinding process improves the activity of RCP to a certain extent, while a long grinding time leads to fusion and aggregation between powders. Investigation on CO2 emission demonstrates that carbon emission from cement production accounts for the largest proportion, 80~95%, in the total emission from mortar production. Combined with the AHP model, eco-efficient mortar containing 15% RCP ground for 50 min and 15% SCGP displays optimal fundamental properties.
Highlights
It is well known that irreversible CO2 emissions will negatively influence the economy, society, ecology, and many other aspects [1]
The authors [35] found that the compounds found in spontaneous combustion gangue powder (SCGP) and recycled concrete powder (RCP) lead to acceptable mechanical properties of mortar
Coal gangue is a kind of solid waste produ mining, which contains an amount of carbon
Summary
It is well known that irreversible CO2 emissions will negatively influence the economy, society, ecology, and many other aspects [1]. Abundant coal resources provide China and the European Union with sufficient energy supply [19], which leads to huge coal gangue emissions. The amount of recycled concrete powder (RCP) generated in the manufacturing process has been increased. The authors [35] found that the compounds found in spontaneous combustion gangue powder (SCGP) and RCP lead to acceptable mechanical properties of mortar. There are some research results on the use of CDW and coal gangue waste, the mixture proportion with relatively superior material properties and environmental impact still needs to be studied. The effect of different grinding times on the performance of eco-efficient mortar was studied to investigate the appropriate manufacturing process of RCP. Combined with the analytical hierarchy process (AHP) method, the fundamental performance of eco-efficient mortar was evaluated and analyzed, which includes mechanical properties (e.g., compressive strength and flexural strength), long-term properties (e.g., chloride resistance and dry shrinkage), and environmental benefits (carbon emissions)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
