再生砖骨料透水混凝土降碱及护坡技术研究

发布时间：2018-06-25 19:03

本文选题：再生砖骨料透水混凝土 + 降碱　；参考：《山东农业大学》2017年硕士论文

【摘要】：环境是人类赖以生存和发展的基础,工程建设往往不可避免的损害当地生态环境,环境恶化给人类生活带来了危害,当今世界,保护环境、可持续发展的呼声越来越高,工程建设也越来越重视与环境相协调。长期以来,我国城镇旧民居很多是用黏土砖作为维护或承重材料,用青瓦或红瓦做屋顶。现在,随着我国城镇化、新农村建设的高速发展,拆迁下来的废弃砖瓦成为固体垃圾,大量占用土地,污染环境。因此,我国目前及今后一个时期废弃粘土砖瓦数量巨大,每年产生约8×106吨。而实际上,因黏土砖瓦具有全天候性、耐候性,这些拆除的砖瓦还有一定强度,还可再利用,可将其破碎、分级、清洗、挂浆强化后作为混凝土的骨料取代天然骨料,制备成再生砖瓦透水混凝土。生态透水混凝土对强度要求不高,而再生砖瓦骨料本身具有一定强度,可以配制中低等级的混凝土,可以作为固沙、固土、固堤护岸材料。透水混凝土空隙率通常在18-25%之间,透水、透气特性好,将其作为骨架,向空隙中填充营养基材并覆一层土壤种植植物,既能加固边坡又保持了绿色景观,维护了生态平衡,可起到一举多得的生态效益。本文主要以废弃砖为原材料,分析借鉴国内外再生骨料混凝土应用技术,深入探索研究了再生砖骨料透水混凝土的制备工艺,物理、力学性能指标,确定简便可行的降碱措施,并进行护坡植生试验。(1)通过测定废弃黏土砖骨料的表观密度、堆积密度、颗粒级配、含水率、吸水率、压碎指标等物理性能,借鉴国内外再生骨料处理工艺,针对废弃黏土砖微裂缝多,强度低等特殊性,研究出适合再生砖骨料的制备、强化工艺。(2)以等量取代水泥用量的方法单掺矿物掺合料粉煤灰、矿渣微粉、硅灰制备再生砖骨料透水混凝土,并进行标准养护,对比研究了不同龄期不同掺量的不同掺合料对混凝土内部孔隙pH的影响规律,以及28天抗压强度值的变化。试验表明,单掺矿物掺合料能够降低再生砖透水混凝土内部孔隙的pH值0.5-1,28天抗压强度较不掺时略有提高,其中硅灰效果最明显。粉煤灰、矿渣适宜掺量10%-30%,硅灰适宜掺量5%-10%。(3)以等量取代水用量的方法添加酸性试剂FeSO_4溶液,制备再生砖骨料透水混凝土,并进行标准养护,研究了不同掺量对混凝土28天抗压强度、内部孔隙中pH的影响。研究表明,FeSO_4溶液浓度在0.25mol/L-0.75mol/L之间时,以10%的FeSO_4溶液取代拌合用水对再生砖透水混凝土的降碱效果较好,能够降低pH值1左右,并且促进水泥水化的进行,使得该混凝土的28天抗压强度较不掺时提高0.5-1MPa。(4)设计并制作了一种半球型的模具,用来制备再生砖透水混凝土单元体,进行护坡植生试验。半球块体的比表面积大,为植物提供更多的生长面积,表面孔隙也为小动物的栖息提供空间,而且,块体之间的空隙适合灌木生长,错落有致的护坡景观更加符合生态要求。(5)综合前期力学性能、透水性和内部孔隙水溶液碱性的研究结果,研究确定合理的护坡技术措施,进行护坡工程试验,观察记录植物长势情况。植物长期生长效果良好,有很好的生态效果。据此,提出合理的施工质量标准及要求,形成护坡施工技术及工艺。
[Abstract]:Environment is the basis of human survival and development, engineering construction often inevitably damage the local ecological environment, environmental deterioration has brought harm to human life. Today, the world, the protection of the environment, the sustainable development of the voice of higher and higher, the engineering construction is more and more important to coordinate with the environment. The clay brick is used as the maintenance or bearing material, and the roof is made of green tiles or red tiles. Now, with the urbanization of China and the rapid development of the new rural construction, the abandoned bricks and tiles which are removed become solid wastes, occupy a large amount of land and pollute the environment. Therefore, the number of clay bricks and tiles is huge, which produces about 8 * 1 a year in China and in the future. 06 tons. In fact, the clay brick and tile have all-weather and weatherability. These bricks and tiles have some strength and can be used again. They can be broken, graded, cleaned and reinforced as concrete aggregate instead of natural aggregate. The tile aggregate itself has a certain strength, which can be made up of middle and low grade concrete, which can be used as sand fixing, solid soil and embankment revetment. The porosity of permeable concrete is usually between 18-25%, water permeable and breathable, which is used as a skeleton, filling the nutrient base material to the gap and covering a layer of soil plant, which can reinforce the slope and keep green. Color landscape, maintaining the ecological balance, can play a great ecological benefit. This paper mainly uses waste bricks as raw materials, analyzes and draws on the application technology of recycled aggregate concrete at home and abroad, and deeply explores the preparation technology, physics, mechanical performance indexes of recycled brick aggregate concrete, and determines the simple and feasible measures for reducing alkali. (1) by measuring the apparent density, accumulation density, grain gradation, water content, water absorption, crushing index, and other physical properties of the waste clay brick aggregate, using the regenerated aggregate treatment technology at home and abroad for reference, the preparation of the recycled brick aggregate and the strengthening process are studied. (2) In order to replace the cement content with the same amount of cement, single mineral admixture fly ash, slag powder and silica fume are used to prepare recycled brick aggregate pervious concrete, and the standard curing is carried out. The influence law of different admixtures on the internal pore pH of concrete at different ages and the change of 28 days compressive strength value are compared. Mineral admixture can reduce the pH value 0.5-1,28 day compressive strength of the inner pore of reclaimed brick permeable concrete slightly higher than that of non admixture, in which the effect of silica fume is the most obvious. Fly ash, slag suitable amount of 10%-30%, suitable dosage of 5%-10%. (3) of silica fume to add acid reagent FeSO_4 solution in the same amount of water content, to prepare recycled brick aggregate Water concrete, and the standard curing, has been carried out to study the effect of different dosage on the 28 day compressive strength of concrete and the effect of pH in the inner pores. The study shows that, when the concentration of FeSO_4 solution is between 0.25mol/L-0.75mol/L, 10% FeSO_4 solution is replaced with water to reduce the alkali effect of the recycled brick pervious concrete, and it can reduce the pH value of about 1 and promote it. The 28 day compressive strength of the concrete is improved by 0.5-1MPa. (4). A hemispherical mold is designed and produced to prepare the regenerated brick pervious concrete unit and carry out the slope protection test. The surface area of the hemispherical block is large, and the surface area of the plant is more, the surface pore is also small movement. The space between the objects is provided with space, and the gap between the blocks is suitable for the growth of shrubs. The wrong slope protection landscape is more in line with the ecological requirements. (5) the research results of the comprehensive early mechanical properties, water permeability and the alkalinity of the inner pore water solution are used to determine the reasonable technical measures for slope protection, to carry out the slope protection engineering test and to observe the plant growth situation. The long-term growth effect of the plant is good and has good ecological effect. Accordingly, reasonable construction quality standards and requirements are put forward, and slope protection construction technology and technology are formed.
【学位授予单位】：山东农业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU528;TU753.8

【参考文献】