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Xiao H, Zhang N, Li G, Zhang Y, Wang Y, Wang Y, Zhang Y. Graphene-Iron Ore Tailings-Based Cementitious Composites with High Early Flexural Strength. MATERIALS (BASEL, SWITZERLAND) 2022; 16:ma16010327. [PMID: 36614666 PMCID: PMC9821977 DOI: 10.3390/ma16010327] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 12/11/2022] [Accepted: 12/23/2022] [Indexed: 06/01/2023]
Abstract
Graphene is a two-dimensional nanomaterial with excellent mechanical, electrical and thermal properties. The application of graphene in cement-based materials has good prospects. However, the mechanical properties of cement-based materials are difficult to be significantly enhanced by ordinary graphene nanoplates. In this paper, nitrogen-doped graphene is first reported as an additive with dosages of 0.01, 0.02, 0.03, 0.04 and 0.05 wt.%, respectively, to prepare iron ore tailings-based cementitious composites. The iron ore tailings-based cementitious composite with 0.02 wt.% graphene shows an extremely high flexural strength of 15.05 MPa at 3 days, which is 134.4% higher than that of the iron ore tailings-based cementitious composite without graphene. The effects of graphene content and curing age on the flexural strength and microstructure of iron ore tailings-based cementitious composites were studied. In particular, the scanning electron microscope was adopted to observe the micromorphology of the composites. It is helpful to understand the graphene reinforcement mechanism for the high early flexural strength of iron ore tailings-based cementitious composites. By altering the morphology of iron ore tailings-based cementitious composites, graphene plays two roles in the composites. One role is to connect C-(A)-S-H gels, ettringite and other hydrated crystals to construct a three-dimensional structure. The other is to attract iron ore tailings distributed on its platform to enhance its flexural strength properties. These findings provide favorable guidance for the performance enhancement and mechanism replenishment of graphene-reinforced cementitious composites.
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Affiliation(s)
- Huiteng Xiao
- Engineering Research Center of Ministry of Education for Geological Carbon Storage and Low Carbon Utilization of Resources, China University of Geosciences (Beijing), Beijing 100083, China
- Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, China University of Geosciences (Beijing), Beijing 100083, China
- National Laboratory of Mineral Materials, China University of Geosciences (Beijing), Beijing 100083, China
- School of Materials Science and Technology, China University of Geosciences (Beijing), Beijing 100083, China
| | - Na Zhang
- Engineering Research Center of Ministry of Education for Geological Carbon Storage and Low Carbon Utilization of Resources, China University of Geosciences (Beijing), Beijing 100083, China
- Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, China University of Geosciences (Beijing), Beijing 100083, China
- National Laboratory of Mineral Materials, China University of Geosciences (Beijing), Beijing 100083, China
- School of Materials Science and Technology, China University of Geosciences (Beijing), Beijing 100083, China
| | - Gen Li
- Engineering Research Center of Ministry of Education for Geological Carbon Storage and Low Carbon Utilization of Resources, China University of Geosciences (Beijing), Beijing 100083, China
- Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, China University of Geosciences (Beijing), Beijing 100083, China
- National Laboratory of Mineral Materials, China University of Geosciences (Beijing), Beijing 100083, China
- School of Materials Science and Technology, China University of Geosciences (Beijing), Beijing 100083, China
| | - Youpeng Zhang
- Engineering Research Center of Ministry of Education for Geological Carbon Storage and Low Carbon Utilization of Resources, China University of Geosciences (Beijing), Beijing 100083, China
- Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, China University of Geosciences (Beijing), Beijing 100083, China
- National Laboratory of Mineral Materials, China University of Geosciences (Beijing), Beijing 100083, China
- School of Materials Science and Technology, China University of Geosciences (Beijing), Beijing 100083, China
| | - Yidi Wang
- Engineering Research Center of Ministry of Education for Geological Carbon Storage and Low Carbon Utilization of Resources, China University of Geosciences (Beijing), Beijing 100083, China
- Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, China University of Geosciences (Beijing), Beijing 100083, China
- National Laboratory of Mineral Materials, China University of Geosciences (Beijing), Beijing 100083, China
- School of Materials Science and Technology, China University of Geosciences (Beijing), Beijing 100083, China
| | - Yu Wang
- Engineering Research Center of Ministry of Education for Geological Carbon Storage and Low Carbon Utilization of Resources, China University of Geosciences (Beijing), Beijing 100083, China
- Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, China University of Geosciences (Beijing), Beijing 100083, China
- National Laboratory of Mineral Materials, China University of Geosciences (Beijing), Beijing 100083, China
- School of Materials Science and Technology, China University of Geosciences (Beijing), Beijing 100083, China
| | - Yihe Zhang
- Engineering Research Center of Ministry of Education for Geological Carbon Storage and Low Carbon Utilization of Resources, China University of Geosciences (Beijing), Beijing 100083, China
- Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, China University of Geosciences (Beijing), Beijing 100083, China
- National Laboratory of Mineral Materials, China University of Geosciences (Beijing), Beijing 100083, China
- School of Materials Science and Technology, China University of Geosciences (Beijing), Beijing 100083, China
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Aziz M, Hamza M, Rasool AM, Ali U, Ahmed T, Kharal ZN, Khan AH, Rehman ZU. Use of Graphene Oxide Nanomaterial to Improve Mechanical Properties of Cement-Treated Silty Soil. ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING 2022. [DOI: 10.1007/s13369-022-07530-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Guo W, Zou S, Pu S, Zhou Y. Study on the Physical and Chemical Properties of Cement-Based Grout Containing Coal-Fly Ash. MATERIALS (BASEL, SWITZERLAND) 2022; 15:8804. [PMID: 36556611 PMCID: PMC9781232 DOI: 10.3390/ma15248804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 12/03/2022] [Accepted: 12/07/2022] [Indexed: 06/17/2023]
Abstract
To study the physical and chemical properties of grout containing fly ash, Class II fly ash was used as a mineral admixture and mixed with silicate cement to produce grout, and the rheological properties, strength properties, hydration properties, and microscopic mechanism were studied. The results of the study showed the following. The incorporation of fly ash reduced the thixotropic area of the composite cement slurry, which facilitated pumping in the pipeline conveying process. The inclusion of fly ash reduced the yield stress and plastic viscosity of the cement paste, but the rheological index increased and then decreased with the increase in fly ash, and the composite paste had the lowest degree of shear thinning at 30% fly ash inclusion. The incorporation of fly ash reduced the hydration exothermic rate and total hydration exothermic amount of the composite slurry and prolonged the hydration induction period, but the promotion effect of fly ash on the hydration rate of cement was obvious at 10% fly ash admixture. The admixture of fly ash increased the empty volume of the composite slurry, but the effect on the most probable aperture was not significant, and the porosity of the system increased, resulting in a decrease in compressive strength. The effect of adding fly ash on the hydration products was reflected mainly by the C-S-H gel produced by cement hydration and the change in calcium alumina and Ca(OH)2. Fly ash does not directly participate in the hydration reaction of cement, but it can promote cement hydration and increase the reaction rate of cement. By analyzing the rheological properties, mechanical properties, and hydration properties of fly ash composite cement paste, the comprehensive analysis found that the rheological properties are excellent when the fly ash admixture is 20-30%, and the water-cement ratio can be reduced to improve the strength without affecting the pumping demand.
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Affiliation(s)
- Wanhong Guo
- Key Laboratory of Ministry for Efficient Mining and Safety of Metal Mines, University of Science and Technology Beijing, Beijing 100083, China
- Sinohydro Foundation Engineering Co., Ltd., Tianjin 301700, China
- PowerChina Road Bridge Group Co., Ltd., Beijing 100048, China
| | - Shizhuo Zou
- Key Laboratory of Ministry for Efficient Mining and Safety of Metal Mines, University of Science and Technology Beijing, Beijing 100083, China
| | - Shaochang Pu
- Key Laboratory of Ministry for Efficient Mining and Safety of Metal Mines, University of Science and Technology Beijing, Beijing 100083, China
| | - Yu Zhou
- Key Laboratory of Ministry for Efficient Mining and Safety of Metal Mines, University of Science and Technology Beijing, Beijing 100083, China
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Effects of Graphene Oxide and Crumb Rubber on the Fresh Properties of Self-Compacting Engineered Cementitious Composite Using Response Surface Methodology. MATERIALS 2022; 15:ma15072519. [PMID: 35407853 PMCID: PMC8999830 DOI: 10.3390/ma15072519] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 03/03/2022] [Accepted: 03/08/2022] [Indexed: 12/10/2022]
Abstract
Graphene oxide-modified rubberized engineered cementitious composite (GO-RECC) is attracting the attention of researchers because of the reported benefits of the GO and crumb rubber (CR) on the strength and deformation properties of the composite. While it is well established that GO negatively affects the workability of cementitious composites, its influence on the attainment of the desired self-compacting (SC) properties of ECC has not yet been thoroughly investigated, especially when combined with crumb rubber (CR). In addition, to simplify the number of trial mixes involved in designing SC-GO-RECC, there is a need to develop and optimize the process using Design of Experiment (DOE) methods. Hence, this research aims to investigate and model using response surface methodology (RSM), the combined effects of the GO and CR on the SC properties of ECC through the determination of T500, slump flow, V-funnel, and L-box ratio of the SC-GORECC as the responses, following the European Federation of National Associations Representing for Concrete (EFNARC) 2005 specifications. The input factors considered were the GO by wt.% of cement (0.02, 0.04, 0.06, and 0.08) and CR as a replacement of fine aggregate by volume (5, 10, and 15%). The results showed that increasing the percentages of GO and CR affected the fresh properties of the SC-GORECC adversely. However, all mixes have T500 of 2.4 to 5.2 s, slump flow of 645 to 800 mm, V-funnel time of 7.1 to 12.3 s, and L-box ratio (H2/H1) of 0.8 to 0.98, which are all within acceptable limits specified by EFNARC 2005. The developed response prediction models were well fitted with R2 values ranging from 91 to 99%. Through the optimization process, optimal values of GO and CR were found to be 0.067% and 6.8%, respectively, at a desirability value of 1.0.
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