Ratio and mechanism of activated magnesium oxide carbonized raw earth block materials
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摘要: 通过单因素条件下抗压强度试验、X射线衍射试验和扫描电镜试验,研究了不同材料掺量和含水率影响下,活性MgO碳化生土砌块的强度和微观形态的变化规律。结果表明：活性MgO碳化生土砌块的原材料配合比MgO∶水泥∶粉煤灰∶生土为7∶7∶6∶80时,按照生土基材最优含水率加入清水混合后,制作而成的砌块抗压强度较高,其21天抗压强度值趋于平稳,平均值能达到7～8 MPa左右；微观测试表明,活性MgO水泥水化和碳化反应,生成的镁式碳酸盐其自身的强度、胶结性能和对孔隙的填充是砌块强度增长的主要原因。Abstract: By means of the single-factor compressive strength tests, X-ray diffraction (XRD) tests and scanning electron microscope (SEM) tests, the variation rules of strength and microscopic morphology of the activated magnesium oxide (MgO) carbonized raw earth blocks under the influences of different material contents and water contents are studied. The results show that when the mixture ratio of raw materials of the active MgO-carbonized raw soil blocks is 7:7:6:80 MgO: cement: fly ash: raw soil and water is added according to the optimal moisture content of raw soil substrate, the compressive strength of the blocks prepared is higher, and the 21-day compressive strength tends to be stable, with an average value of about 7~8 MPa. The XRD and SEM tests show that the strength, cementing property and pore filling of magnesium-type carbonate generated by hydration and carbonation reaction of the active MgO cement are the main reasons for the increase of strength of the blocks.
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图 1 砌块碳化图及抗压强度测试图
Figure 1. Diagram of block carbonization and compressive strength tests
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图 2 不同质量比活性MgO水泥碳化生土砌块抗压抗压强度
Figure 2. Compressive strengths of carbonized clay blocks with active MgO cement at different mass ratios
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图 4 不同活性MgO水泥掺量下的抗压强度
Figure 4. Compressive strengths of MgO cement with different active contents
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图 6 不同粉煤灰掺量下的碳化生土砌块SEM照片
Figure 6. SEM photos of carbonized clay blocks with different fly ash contents
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[1] 王毅红, 王春英, 李先顺, 等. 生土结构的土料受压及受剪性能试验研究[J]. 西安科技大学学报, 2006, 26(4): 469-472, 484. doi: 10.3969/j.issn.1672-9315.2006.04.008 WANG Yi-hong, WANG Chun-ying, LI Xian-shun, et al. Experiment on shear properties and compressive properties of earth material of raw-soil structure[J]. Journal of Xi'an University of Science and Technology, 2006, 26(4): 469-472, 484. (in Chinese) doi: 10.3969/j.issn.1672-9315.2006.04.008
[2] 赵成. 改性土坯砌体抗压强度试验研究[D]. 乌鲁木齐: 新疆大学, 2010. ZHAO Cheng. Experimental Study on Compressive Strength of Modified Adobe Masonry[D]. Urumqi: Xinjiang University, 2010. (in Chinese)
[3] 尚建丽. 传统夯土民居生态建筑材料体系的优化研究[D]. 西安: 西安建筑科技大学, 2005. SHANG Jian-li. A study of Optimization of the Ecological Building Material System of Traditional Rammed Earth Dwellings[D]. Xi'an: Xi'an University of Architecture and Technology, 2005. (in Chinese)
[4] HARRISON A J W. Reactive magnesium oxide cements: US7347896[P]. 2008-03-25.
[5] HARRISON J. New cements based on the addition of reactive magnesia to Porland cement with or with or without addedpozzolan[C]//Proceedings of the CIA Conference: Concrete in the Third Millennium, 2003, Brisbane
[6] HARRISON A J W. Reactive Magnesium Oxide Cements: US7347896[P]. 2008-03-25.
[7] VANDEPERRE L J, LISKA M, AL-TABBAA A. Mixtures of pulverized fuel ash, Portland cement and Magnesium oxide: strength evolution and hydration products[C]//Sixth International Conference on the Science and Engineering of Recycling for Environmental Protection, 2006, Belgrade.
[8] VANDEPERRE L J, LISKA M, AL-TABBAA A. Hydration and mechanical properties of magnesia, pulverized fuel ash, and Portland cement blends[J]. Journal of Materials in Civil Engineering, 2008, 20(5): 375-383. doi: 10.1061/(ASCE)0899-1561(2008)20:5(375)
[9] VANDEPERRE L J, LISKA M, AL-TABBAA A. Microstructures of reactive magnesia cement blends[J]. Cement and Concrete Composites, 2008, 30(8): 706-714. doi: 10.1016/j.cemconcomp.2008.05.002
[10] LISKA M, VANDEPERRE L J, Al-TABBAA A. Mixtures of pulverised fuel ash, Portland cement and Magnesium oxide: characterization of pastes and setting behaviour[C]//6th International Conference on the Environmental and Technical Implications of Construction with Alternative Materials, Belgrade, 2006.
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