Research on the Application of Iron Tailings as Intelligent Road Materials

Solution: (1) Conduct indoor experiments on the physical and mechanical properties of iron tailings, analyze the performance of iron tailings fillers, and clarify the classification standards and methods for iron tailings fillers. (2) Using a centrifuge to conduct experiments on iron tailings filling, simulate the stress situation in the embankment, and study its deformation characteristics, permeability characteristics, and stability laws. (3) Using finite element models and other methods, the deformation laws of iron tailings embankments and embankments were studied. (4) Propose a reasonable structural system based on "stability control and deformation control" for iron tailings embankments and embankments, providing theoretical guidance for the design and construction of iron tailings fillers. (5) Propose technical requirements for iron tailings from different sources and qualities that can be used as road maintenance materials. Based on the characteristics of mineral sand and the current technical requirements for road maintenance materials, technical indicators suitable for the characteristics of iron tailings in Hebei Province are proposed. The proposal of technical indicators and standards is beneficial for guiding waste disposalEngineering recycling and utilization of abandoned iron tailings. (6) Based on the physical characteristics of iron tailings, propose a reasonable range of sealing layer and cover grading. Due to the different processing techniques of iron tailings, the thickness varies. In order to make the design more suitable for the physical characteristics of iron tailings particles, it is necessary to improve the grading range of the construction seal and cover design. (7) Propose technical requirements for intelligent materials that can be used for self repair of asphalt roads based on iron tailings from different sources and qualities. Based on the inherent characteristics of iron tailings and the magnetic and conductive properties of iron tailings, combined with the technical requirements of intelligent road materials, technical indicators suitable for the characteristics of iron tailings in our province are proposed, and reasonable requirements for intelligent road material indicators are proposed. The proposal of technical indicators and standards is conducive to guiding the engineering recycling and utilization of abandoned iron tailings, and has important guiding significance. Expected goal 1: Continue to promote the research and development of iron tailings as building aggregates in concrete, and increaseMarket development efforts will be made to apply iron tailings as new materials in urban construction projects. 2. This study conducted a systematic study on the stability and deformation characteristics of iron tailings embankments and embankments, as well as the reasonable structural system, through indoor experiments, on-site experiments, numerical analysis, and other methods. The concept of a reasonable iron tailings roadbed and embankment structural system was proposed, and the application effect of iron tailings embankment and embankment technology was analyzed. 3. This study will conduct a systematic study on the technical requirements of raw materials, mixture design methods, construction process characteristics, and other issues when using iron tailings solid waste ore sand for road maintenance through indoor experiments and on-site experiments. Propose technical means and measures for guiding the application of iron tailings solid waste ore sand, and evaluate its application effect and long-term performance based on on-site testing. 4. This study will investigate the application of iron tailings in rainwater runoff reduction facilities to reduce emissionsThe feasibility of water pollution. The focus is on the ability to remove nutrients in permeable paving facilities. The large-scale application of iron tailings in the construction of sponge cities in China can provide a way to reduce the stacking of iron tailings and alleviate the environmental and public safety hazards of iron tailings in Hebei. 5. This study conducts a systematic study on the technical requirements for raw materials, mixture design methods, and construction process characteristics of iron tailings as intelligent road materials through indoor experiments combined with on-site test road implementation. Propose technical means and measures to guide the application of iron tailings as intelligent road materials, and evaluate their application effectiveness and long-term performance in combination with on-site test roads. 6. Due to the different genetic types of iron tailings, their magnetic and conductive properties vary. In order to make the iron tailings more suitable for the technical requirements of intelligent road materials, it is necessary to conduct experimental analysis on different iron tailings and matching tests on electromagnetic heating equipment for different road surfaces,And finally, reasonable requirements for absorbing material indicators applicable to intelligent road materials are proposed. Iron tailings are the waste discharged by iron ore dressing plants under specific economic and technological conditions by grinding iron ore and selecting "useful components". Iron tailings are the waste discharged by iron ore dressing plants under specific economic and technological conditions by grinding iron ore and selecting "useful components". According to incomplete statistics, there are currently more than 150 types of minerals discovered in China, with over 8000 mines developed and established, producing a total of 5.97 billion tons of tailings. Among them, the amount of iron tailings stored is over one billion tons, accounting for nearly one-third of the total amount of tailings stored. Moreover, nearly 300 million tons of iron tailings are discharged every year, with a comprehensive utilization rate of less than 20%. The massive storage of iron tailings not only occupies land and causes resource waste, but also brings serious pollution and harm to human living environment, disrupting ecological balance. Some mining developed countries such as the United States and Russia began recycling tailings as early as the early 1960sBy utilizing research work, some mines have now achieved tailless production. Foreign countries attach great importance to the comprehensive utilization of iron tailings, pay attention to the recovery of valuable components, and widely search for various ways to utilize iron tailings. The research on using tailings as building materials in China began in the 1980s. Due to different origins and beneficiation processes, the composition and content of tailings vary, mainly containing silicon, aluminum, calcium, magnesium oxides, as well as a small amount of potassium, sodium, iron, and sulfur oxides. Among them, the silicon and aluminum content is high, which is very similar to building materials. As long as a small amount of other raw materials are added and properly blended, they can be used as raw materials for many building materials, providing a prerequisite for the widespread application of tailings in the building materials industry. Using iron tailings as raw materials to produce various building materials products has lower costs, high tailings utilization rate, and large usage. It not only utilizes waste, reduces environmental pollution, but also saves a lot of land. Not only does it provide an ideal raw material for the building materials industry, but it also reduces the demand for mineral processing technologyThe development of tailings and tailings free direction has created conditions. This project has conducted research on (1) the classification of iron tailings distributed in Hebei Province based on the genetic types and production processes of iron ore. The performance characteristics of different iron tailings materials are determined from the aspects of chemical composition, mineral composition, particle size, etc., and the technical and economic feasibility of using them as building aggregates is studied. And using iron tailings solid waste as concrete aggregate instead of natural sand and gravel to prepare concrete below C60, suitable for construction and municipal engineering. (2) By studying the workability, mechanical properties, and durability of sedimentary metamorphic, magmatic, contact metasomatic, and sedimentary iron tailings concrete, and comparing it with ordinary crushed stone concrete, the characteristics of different types of iron tailings concrete were found. (3) By compounding iron tailings with ultra-fine sand, fine sand, and ordinary medium coarse sand, a mixed iron tailings sand is formed to improve its particle grading, and to improve the workability, mechanical properties, and durability of the concrete prepared with itResearch to determine the most economical and reasonable dosage. (4) The first local standard for the application technology of iron tailings concrete in China has been formulated, which has played a positive role in promoting the promotion and utilization of iron tailings sand and gravel in our province and the comprehensive utilization of iron tailings. The project will further study the wide application prospects of iron tailings in embankment and embankment filling, intelligent material technology for roads, and sponge city construction. This project will conduct systematic research on them. (1) Research on the Application of Iron Tailings as Embankment and Dam Filler Research on Solid Waste of Iron Tailings in Our Province shows that there are many types of iron tailings, which can be divided into coarse sand, fine sand, and ultra-fine sand, with different chemical composition and mineral composition. Although the types are different, their physical and chemical properties are stable, and their strength can meet the requirements. This provides a foundation for the application of iron tailings in embankments and embankment fillers. In order to avoid the damage of soil extraction to farmland and farmland, various alternative roadbed and embankment fillers are constantly being applied in engineeringIn practice, fine sand has been widely used as an alternative roadbed filler in coastal areas along the Yangtze River. Iron tailings, as a type of sand and gravel, can be applied to fine sand embankments and embankment technology, which is of great significance for improving the level of road engineering construction, protecting farmland, and protecting the ecological environment. On the other hand, due to the fact that iron tailings are non cohesive granular materials, their mechanical properties differ significantly from traditional embankment and embankment fillers. The shear strength of clay is composed of internal friction angle and cohesion, and its permeability is very poor. The cohesion of iron tailings is almost zero, and their shear strength is mainly composed of internal friction angles. They have good permeability and differ from the physical and mechanical properties of ordinary clay. Therefore, their applicability, compaction, and stability as roadbed and embankment fillers need to be highly valued. Iron tailings fillers have low adhesion and are easy to loosen, so compaction of fillers is a difficult problem in construction. Compaction technology has become the key to the application of iron tailings in embankment and dam engineering. (2) Iron tailResearch on the Application of Mine as an Intelligent Material for Self repair of Asphalt Roads According to the research results of the project "Research on the Performance of Solid Waste of Iron Tailings as Building Aggregates in Hebei Province and Its Application in Concrete", there are many types of iron tailings in our province, and their chemical and mineral compositions are also different. However, their basic physical and chemical properties are stable. From the perspective of particle size, there are differences in the particle size distribution of iron tailings in different regions. For example, Tangshan iron tailings are mostly coarse sand, with a fineness modulus generally between 2.3 and 3.0. In other areas of Chengde, the fineness modulus of iron tailings is mostly between 1.6 and 2.1, and it is mostly fine sand. In places such as Handan and Xingtai, it is mostly tailings pond raw sand, with a fineness modulus between 0.8 and 1.5, and it is mostly ultra-fine sand. Due to the wide range of particle size distribution, narrow particle size distribution, and more angular shape of iron tailings sand, it is an ideal choice to use iron tailings sand as artificial sand instead of natural sand for road construction materials. However, road construction materials consume a large amount of resources, asThis will also become an effective way to handle a large amount of tailings solid waste. Under the influence of traffic load and climate, the condition and service capacity of asphalt pavement will gradually deteriorate over time. In order to maintain the performance of asphalt pavement and extend its service life, different maintenance and repair measures need to be adopted at different stages of the life cycle. The most commonly used preventive maintenance techniques are surface sealing and thin layer covering. Due to the functional requirements of the sealing layer and thin layer cover, there are high technical requirements for materials, especially aggregates, such as wear resistance. The existing research results show that iron tailing sand has good firmness, crushing capacity, low active ingredients and good chemical stability, so it is an ideal choice for road maintenance. Developing an intelligent and self repairing asphalt road will extend the service life of the road, significantly reduce maintenance costs, and improve road quality. This intelligent road is planned to use electromagnetic repair technologyRationally, using absorbing materials as road construction materials for construction, the spatial structure formed by high magnetic and conductive materials converts electromagnetic field energy into thermal energy. Utilizing specific wavelengths and frequencies of electromagnetic waves to form effective electromagnetic fields in the area to be heated, the absorbing material absorbs the electromagnetic waves that irradiate its micro clusters and converts them into heat energy, thereby achieving the goal of repairing aged asphalt concrete. This study aims to analyze the electrical resistivity and dielectric constant characteristics of various types of iron tailings in Hebei Province, and determine the iron tailings materials suitable for intelligent and self repairing asphalt roads. (3) Research on the Application of Iron Tailings as New Materials in Sponge City Construction ① Research on the Application of Iron Tailings as Aggregates in Permeable Concrete The General Office of the State Council issued the "Guiding Opinions on Promoting Sponge City Construction" in October 2015, deploying and promoting the construction of sponge cities. To build a sponge city, it is necessary to have a "sponge body", which means low impact rainwater development technology. Permeable pavement, sinking typeGreen spaces, biological retention and other infiltration and emission reduction facilities are important components of the urban "sponge". Rainwater infiltrates, accumulates, purifies, and reuses through these "sponge bodies", and the remaining runoff is discharged through pipe networks and pumping stations, effectively improving the standards of urban drainage systems and alleviating the pressure of urban waterlogging. Iron tailings were used as concrete aggregates instead of natural sand and gravel to prepare concrete below C60, which is suitable for construction and municipal engineering in terms of technical and economic feasibility. In the preliminary research of the project, preliminary results have been achieved and applied in the project, providing a theoretical basis and engineering practice for its application as aggregates in permeable concrete Research on the Application of Iron Tailings as Wastewater Filtration Materials Phosphates are a major source of eutrophic pollution in rivers in China. Research has shown that iron tailings contain the main components that adsorb phosphides, iron oxide and aluminum oxide. Their ability to absorb phosphides ranges from 8.2 to 12.6mg/g, which is the main source of eutrophic pollution in rivers in ChinaThis indicates that iron tailings have the ability to control water pollution. The application of iron tailings as the main material for producing "sewage filter bodies" in sewage treatment will play an important role in the construction of sponge cities. Relevant foreign experts Zhang Yuqing, YuqingZhang, PHD, Prof.AstonUniversity, Birmingham, UK Huang Baoshan, Professor, University of Tennessee (Knoxville Campus) who have already collaborated with us