偏高岭土—矿渣体系轻骨料混凝土的制备与性能研究
发布时间：2019-04-15 12:22
【摘要】：高强高性能混凝土是目前工程中被广泛应用的材料。为了减轻普通混凝土的重量并希望将其运用于一些特定的环境中,人们制备出了高强高性能轻骨料混凝土。这种轻骨料混凝土因具有轻质、高强、高耐久、耐火等特点,而被大量应用于高层建筑和桥梁工程。为了弥补高性能轻骨料混凝土收缩较大的缺陷,国内外许多研究者们采用掺火山灰材料等技术措施改善轻骨料混凝土,以改善轻骨料混凝土的体积稳定性。偏高岭土是一种高活性的火山灰材料,对混凝土性能的改善效果与硅灰相近,远远高于粉煤灰和矿渣。偏高岭土还能大幅减少混凝土的收缩,且价格比硅灰低。故使用偏高岭土替代硅灰制备高性能轻骨料混凝土具有较高的理论意义和实用价值。另一方面,沿海地区混凝土工程和海上混凝土工程中使用的水是自来水或者淡化后的海水。水的运输和处理增加了工程成本。海水中富含多种盐,部分盐能促进水化,部分盐离子会导致混凝土结构的破坏,其中,海水中的氯离子是造成钢筋锈蚀和结构破坏的主要介质。研究表明,偏高岭土具有很强氯离子能力固化能力,那么,在海水拌合制备的混凝土中,掺入适量偏高岭土能否弥补海水带来的不良影响,同时又保留海水对混凝土的好的影响?此问题值得我们研究。鉴于此,本文使用了偏高岭土和矿渣制备了淡水和海水两种体系的轻骨料混凝土。矿渣的使用能降低混凝土的成本,并能改善混凝土的堆积结构,使混凝土结构更加紧密。在保证混凝土工作性能的前提下,本文通过XRD、SEM、DSC-TG、MIP等先进的测试方法研究了不同掺量的偏高岭土和矿渣对轻骨料混凝土宏观及微观性能的影响,研究了海水和偏高岭土、矿渣对轻骨料混凝土性能的复合影响,分析了使用海水和偏高岭土、矿粉制备轻骨料混凝土的可行性。本文的主要成果如下:1、本文结合力学性能与微观结构,证明了单独掺入偏高岭土和矿渣均可以提高轻骨料混凝土的性能,而单独掺入偏高岭土效果更佳。复合掺入偏高岭土和矿渣能进一步提升混凝土的力学性能。复合掺入偏高岭土和矿渣时,最佳掺量为10%偏高岭土和10%矿渣。实验证明,偏高岭土和矿渣有效改善了轻骨料混凝土过渡界面区的结构,增强了界面过渡区骨料和水泥浆体间的结合,提高了界面的强度,并改善了水泥浆体的组成与结构,从而提高轻骨料混凝土的宏观力学性能。2、相比淡水体系轻骨料混凝土,海水体系轻骨料混凝土微观结构更密实,过渡界面区强度更高,混凝土抗压强度更高。实验证明了海水的使用能提高轻骨料混凝土的力学性能。且海水不影响矿物掺合料对混凝土性能的改善作用。3、测试结果证明,海水引入了大量氯离子,部分氯离子与水化产物反应生成弗里德尔盐。偏高岭土和矿渣的掺入能提高弗里德尔盐的生成量,生成量随着偏高岭土和矿渣掺量的增加而增加。海水还会促进水泥水化,生成更多水化产物。而偏高岭土和矿渣能通过大量消耗水化产物Ca(OH)2促进水泥的水化。4、未掺入矿物的轻骨料混凝土的抗氯离子侵蚀能力较低。掺入偏高岭土和矿渣均能增强轻骨料混凝土的抗氯离子侵蚀性能,复合掺入偏高岭土和矿渣效果最佳。而海水的引入会降低混凝土抗氯离子渗透性能,降低混凝土耐久性。掺入偏高岭土和矿渣后能明显改善海水体系轻骨料混凝土抗氯离子渗透性能,能弥补海水引入的离子所带来的不良影响。5、未掺入矿物的轻骨料混凝土的体积收缩变形量较大。掺入偏高岭土和矿渣均能减少轻骨料混凝土的体积收缩。单独掺入偏高岭土效果比单独掺入矿渣效果好,在一定掺量条件下,随着偏高岭土掺量的增加,轻骨料混凝土的体积变形量越小。复合掺入偏高岭土和矿渣能在单独掺入某一矿物的改善效果上进一步减少轻骨料混凝土的体积收缩。但当偏高岭土掺量达10%后,再掺入矿渣时对轻骨料混凝土的体积变形影响很小。
[Abstract]:High-strength and high-performance concrete is a widely used material in the current project. High-strength and high-performance light aggregate concrete is prepared in order to reduce the weight of the common concrete and to use it in a number of specific environments. The lightweight aggregate concrete has the characteristics of light weight, high strength, high durability, fire resistance and the like, and is widely applied to high-rise building and bridge engineering. In order to make up for the defects of high performance and light aggregate concrete shrinkage, many researchers at home and abroad use the technical measures such as pozzolanic material to improve the light aggregate concrete to improve the volume stability of the lightweight aggregate concrete. The metakaolin is a highly active pozzolanic material, and the effect of improving the performance of the concrete is similar to that of the silicon ash, which is much higher than that of the fly ash and the slag. The metakaolin can also greatly reduce the shrinkage of the concrete, and the price is lower than that of the silicon ash. Therefore, the use of metakaolin for the preparation of high-performance light-aggregate concrete with high-performance light-aggregate concrete has higher theoretical and practical value. On the other hand, the water used in the coastal concrete and marine concrete works is tap water or desalinated seawater. The transportation and treatment of water increases the cost of the work. The sea water is rich in various salts, some of which can promote the hydration, and some of the salt ions can cause the destruction of the concrete structure, in which the chloride ion in the seawater is the main medium which causes the corrosion and the structure of the steel bar. The research shows that the metakaolin has a strong ability to cure the chloride ion, then, in the concrete prepared by sea water mixing, it can make up the bad influence of the sea water by adding a proper amount of metakaolin, and at the same time, keep the good effect of the sea water on the concrete. The question is worthy of our study. In view of this, the paper uses the metakaolin and the slag to prepare the light aggregate concrete of the two systems of fresh water and sea water. The use of the slag can reduce the cost of the concrete, and can improve the stacking structure of the concrete and make the concrete structure more compact. The effects of different amounts of metakaolin and slag on the macro-and micro-properties of light-aggregate concrete were studied by means of advanced test methods such as XRD, SEM, DSC-TG and MIP. The effects of different amounts of metakaolin and slag on the macro-and micro-properties of light-aggregate concrete were studied by means of advanced test methods such as XRD, SEM, DSC-TG and MIP. The effect of slag on the performance of light aggregate concrete is analyzed, and the feasibility of using sea water and metakaolin and mineral powder to prepare lightweight aggregate concrete is analyzed. The main results of this paper are as follows:1. The properties of the lightweight aggregate concrete can be improved by the combination of the mechanical properties and the microstructure. The composite incorporation of the metakaolin and the slag can further improve the mechanical properties of the concrete. The optimum mixing amount is 10% metakaolin and 10% slag when mixed with metakaolin and slag. the experiment proves that the metakaolin and the slag can effectively improve the structure of the transition interface area of the light aggregate concrete, enhance the bonding between the aggregate and the cement slurry body in the interface transition area, improve the strength of the interface, and improve the composition and the structure of the cement slurry body, So as to improve the macro-mechanical property of the light aggregate concrete, and 2, the light aggregate concrete of the fresh water system is more dense than the light aggregate concrete of the seawater system, the strength of the transition interface area is higher, and the compressive strength of the concrete is higher. The experiment shows that the use of sea water can improve the mechanical properties of light aggregate concrete. And the seawater does not influence the improvement of the mineral admixture on the performance of the concrete. The incorporation of the metakaolin and the slag can increase the amount of the Friedel salt, and the amount of production is increased with the increase of the amount of the metakaolin and the slag. The sea water will also promote the hydration of the cement to produce more hydration products. And the metakaolin and the slag can promote the hydration of the cement by a large amount of the hydration product Ca (OH)2. The addition of the metakaolin and the slag can enhance the chloride ion corrosion resistance of the light aggregate concrete, and the combination of the metakaolin and the slag is the best. And the introduction of sea water can reduce the chloride ion penetration performance of the concrete and reduce the durability of the concrete. After the addition of the metakaolin and the slag, the anti-chloride ion permeability of the light aggregate concrete of the seawater system can be obviously improved, the adverse effect caused by the ions introduced by the seawater can be compensated, and the volume shrinkage deformation amount of the lightweight aggregate concrete which is not incorporated into the mineral is large. The incorporation of metakaolin and slag can reduce the volume shrinkage of light aggregate concrete. The effect of separately incorporating the metakaolin is better than that of the separately incorporated slag, and the smaller the volume deformation of the lightweight aggregate concrete with the increase of the amount of the metakaolin in a certain amount. The composite incorporation of the metakaolin and the slag can further reduce the volume contraction of the lightweight aggregate concrete on the basis of the improved effect of the incorporation of a mineral alone. However, when the amount of the metakaolin reaches 10%, the volume deformation of the lightweight aggregate concrete is very small when the slag is mixed with the slag.
【学位授予单位】：武汉理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU528
[Abstract]:High-strength and high-performance concrete is a widely used material in the current project. High-strength and high-performance light aggregate concrete is prepared in order to reduce the weight of the common concrete and to use it in a number of specific environments. The lightweight aggregate concrete has the characteristics of light weight, high strength, high durability, fire resistance and the like, and is widely applied to high-rise building and bridge engineering. In order to make up for the defects of high performance and light aggregate concrete shrinkage, many researchers at home and abroad use the technical measures such as pozzolanic material to improve the light aggregate concrete to improve the volume stability of the lightweight aggregate concrete. The metakaolin is a highly active pozzolanic material, and the effect of improving the performance of the concrete is similar to that of the silicon ash, which is much higher than that of the fly ash and the slag. The metakaolin can also greatly reduce the shrinkage of the concrete, and the price is lower than that of the silicon ash. Therefore, the use of metakaolin for the preparation of high-performance light-aggregate concrete with high-performance light-aggregate concrete has higher theoretical and practical value. On the other hand, the water used in the coastal concrete and marine concrete works is tap water or desalinated seawater. The transportation and treatment of water increases the cost of the work. The sea water is rich in various salts, some of which can promote the hydration, and some of the salt ions can cause the destruction of the concrete structure, in which the chloride ion in the seawater is the main medium which causes the corrosion and the structure of the steel bar. The research shows that the metakaolin has a strong ability to cure the chloride ion, then, in the concrete prepared by sea water mixing, it can make up the bad influence of the sea water by adding a proper amount of metakaolin, and at the same time, keep the good effect of the sea water on the concrete. The question is worthy of our study. In view of this, the paper uses the metakaolin and the slag to prepare the light aggregate concrete of the two systems of fresh water and sea water. The use of the slag can reduce the cost of the concrete, and can improve the stacking structure of the concrete and make the concrete structure more compact. The effects of different amounts of metakaolin and slag on the macro-and micro-properties of light-aggregate concrete were studied by means of advanced test methods such as XRD, SEM, DSC-TG and MIP. The effects of different amounts of metakaolin and slag on the macro-and micro-properties of light-aggregate concrete were studied by means of advanced test methods such as XRD, SEM, DSC-TG and MIP. The effect of slag on the performance of light aggregate concrete is analyzed, and the feasibility of using sea water and metakaolin and mineral powder to prepare lightweight aggregate concrete is analyzed. The main results of this paper are as follows:1. The properties of the lightweight aggregate concrete can be improved by the combination of the mechanical properties and the microstructure. The composite incorporation of the metakaolin and the slag can further improve the mechanical properties of the concrete. The optimum mixing amount is 10% metakaolin and 10% slag when mixed with metakaolin and slag. the experiment proves that the metakaolin and the slag can effectively improve the structure of the transition interface area of the light aggregate concrete, enhance the bonding between the aggregate and the cement slurry body in the interface transition area, improve the strength of the interface, and improve the composition and the structure of the cement slurry body, So as to improve the macro-mechanical property of the light aggregate concrete, and 2, the light aggregate concrete of the fresh water system is more dense than the light aggregate concrete of the seawater system, the strength of the transition interface area is higher, and the compressive strength of the concrete is higher. The experiment shows that the use of sea water can improve the mechanical properties of light aggregate concrete. And the seawater does not influence the improvement of the mineral admixture on the performance of the concrete. The incorporation of the metakaolin and the slag can increase the amount of the Friedel salt, and the amount of production is increased with the increase of the amount of the metakaolin and the slag. The sea water will also promote the hydration of the cement to produce more hydration products. And the metakaolin and the slag can promote the hydration of the cement by a large amount of the hydration product Ca (OH)2. The addition of the metakaolin and the slag can enhance the chloride ion corrosion resistance of the light aggregate concrete, and the combination of the metakaolin and the slag is the best. And the introduction of sea water can reduce the chloride ion penetration performance of the concrete and reduce the durability of the concrete. After the addition of the metakaolin and the slag, the anti-chloride ion permeability of the light aggregate concrete of the seawater system can be obviously improved, the adverse effect caused by the ions introduced by the seawater can be compensated, and the volume shrinkage deformation amount of the lightweight aggregate concrete which is not incorporated into the mineral is large. The incorporation of metakaolin and slag can reduce the volume shrinkage of light aggregate concrete. The effect of separately incorporating the metakaolin is better than that of the separately incorporated slag, and the smaller the volume deformation of the lightweight aggregate concrete with the increase of the amount of the metakaolin in a certain amount. The composite incorporation of the metakaolin and the slag can further reduce the volume contraction of the lightweight aggregate concrete on the basis of the improved effect of the incorporation of a mineral alone. However, when the amount of the metakaolin reaches 10%, the volume deformation of the lightweight aggregate concrete is very small when the slag is mixed with the slag.
【学位授予单位】：武汉理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU528
【参考文献】
相关期刊论文 前10条
1 秦淑芳;申向东;;偏高岭土对天然轻骨料混凝土力学性能影响的研究[J];硅酸盐通报;2013年06期
2 水中和;王康;陈伟;孔，
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