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Cheng Y, Sun L, Li Y, Liu M, He R, Jin X, Jin H. Damage Model of Steel Fiber-Reinforced Coal Gangue Concrete under Freeze-Thaw Cycles Based on Weibull Distribution. MATERIALS (BASEL, SWITZERLAND) 2023; 16:6775. [PMID: 37895756 PMCID: PMC10608513 DOI: 10.3390/ma16206775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 10/08/2023] [Accepted: 10/16/2023] [Indexed: 10/29/2023]
Abstract
In order to improve the utilization rate of coal gangue and expand the application range of coal gangue concrete (CGC), a certain proportion of steel fiber was added to the concrete, and the freeze-thaw cycles (FTCs) and flexural tests were used to explore the effects of different mass replacement rates of coal gangue (0%, 25%, 50%, 75%, and 100%) and different proportions of the volumetric blending of the steel fiber (0%, 0.8%, 1.0%, and 1.2%) on the frost resistance of steel fiber-reinforced CGC (SCGC). The governing laws of mass loss rate, relative dynamic elastic modulus and load-midspan deflection curve were obtained on the base of the analysis of testing results. The damage mechanisms of the SCGC under the FTCs were analyzed using the results of scanning electron microscopy (SEM). Based on the Lemaitre's strain equivalence principle and Krajcinovic's vector damage theory, a damage evolution model of the SCGC under the FTCs was established by introducing the damage variable of the SCGC satisfying Weibull distribution. The results show an increasing mass loss rate of the SCGC and a decreasing relative dynamic elastic modulus with an increasing mass replacement rate of coal gangue. The proper content of the steel fiber can reduce the mass loss rate of concrete by 10~40% and the relative loss rate of dynamic elastic modulus of concrete by 2~8%, thus significantly improving the ductility and toughness of the concrete. The established damage evolution model is well validated by the experimental results, which further help to improve the modelling accuracy. This study provides key experimental data and a theoretical basis for a wider range of proper utilization of coal gangue in cold regions.
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Affiliation(s)
- Yaohui Cheng
- School of Civil Engineering and Transportation, Permafrost Institute, China-Russia Joint Laboratory of Cold Regions Engineering and Environment, Northeast Forestry University, Harbin 150040, China; (Y.C.); (M.L.); (H.J.)
- Liaoning Provincial Key Laboratory of Coal Gangue Resource Utilization and Energy-Saving Building Materials, School of Civil Engineering, Liaoning Technical University, Fuxin 123000, China;
| | - Li Sun
- Department of Housing and Urban-Rural Development of Heilongjiang Province, Harbin 150070, China
| | - Yongjing Li
- Liaoning Provincial Key Laboratory of Coal Gangue Resource Utilization and Energy-Saving Building Materials, School of Civil Engineering, Liaoning Technical University, Fuxin 123000, China;
| | - Mengxin Liu
- School of Civil Engineering and Transportation, Permafrost Institute, China-Russia Joint Laboratory of Cold Regions Engineering and Environment, Northeast Forestry University, Harbin 150040, China; (Y.C.); (M.L.); (H.J.)
| | - Ruixia He
- State Key Laboratory of Frozen Soils Engineering, State Key Laboratory of Cryosphere Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China;
| | - Xiaoying Jin
- School of Civil Engineering and Transportation, Permafrost Institute, China-Russia Joint Laboratory of Cold Regions Engineering and Environment, Northeast Forestry University, Harbin 150040, China; (Y.C.); (M.L.); (H.J.)
| | - Huijun Jin
- School of Civil Engineering and Transportation, Permafrost Institute, China-Russia Joint Laboratory of Cold Regions Engineering and Environment, Northeast Forestry University, Harbin 150040, China; (Y.C.); (M.L.); (H.J.)
- State Key Laboratory of Frozen Soils Engineering, State Key Laboratory of Cryosphere Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China;
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Zhao Y, Zhang Z, Ji Y, Song L, Ma M. Experimental Research on Improving Activity of Calcinated Coal Gangue via Increasing Calcium Content. MATERIALS (BASEL, SWITZERLAND) 2023; 16:2705. [PMID: 37049001 PMCID: PMC10095759 DOI: 10.3390/ma16072705] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/19/2023] [Revised: 03/19/2023] [Accepted: 03/21/2023] [Indexed: 06/19/2023]
Abstract
In this investigation, non-spontaneous combustion coal gangue was activated by two methods: (1) low-temperature calcination and (2) calcium addition. Differences in the activity of the activated coal gangue were studied at various calcination temperatures and amounts of calcium addition. Meanwhile, the cementation activity of the activated coal gangue was evaluated according to the activity effect analysis. Furthermore, the influences of the activated coal gangue on the cementation activity of cement were investigated. The results indicated that the activities of the activated coal gangue increased at a temperature between 500 °C and 700 °C. The calcium addition method can also increase the activity of coal gangue, with the effect being better when the gangue is mixed with slag. The addition of calcium and the calcination of coal gangue can promote the production of active minerals such as metakaolin, which is the main reason for the increased cementation activity.
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Affiliation(s)
- Yanpeng Zhao
- Xuzhou Yinshan Track Concrete Co., Ltd., Xuzhou Metro Infrastructure Engineering Co., Ltd., Xuzhou Metro Group Co., Ltd., Xuzhou 221000, China
- Jiangsu Key Laboratory Environmental Impact and Structural Safety in Engineering, China University of Mining and Technology, Xuzhou 221116, China
| | - Zhongzhe Zhang
- Jiangsu Key Laboratory Environmental Impact and Structural Safety in Engineering, China University of Mining and Technology, Xuzhou 221116, China
- Jiangsu Collaborative Innovation Center for Building Energy Saving and Construct Technology, Jiangsu Vocational Institute of Architectural Technology, Xuzhou 221116, China
| | - Yongsheng Ji
- Jiangsu Key Laboratory Environmental Impact and Structural Safety in Engineering, China University of Mining and Technology, Xuzhou 221116, China
| | - Lei Song
- Jiangsu Key Laboratory Environmental Impact and Structural Safety in Engineering, China University of Mining and Technology, Xuzhou 221116, China
| | - Mingming Ma
- Jiangsu Key Laboratory Environmental Impact and Structural Safety in Engineering, China University of Mining and Technology, Xuzhou 221116, China
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