· 5.2. Critical raw materials and circular economy Given the evolution of the context regarding mineral resources and the necessity to recycle, old waste deposits related to past mining and metallurgical activities can be
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In this paper, the effects of steam curing conditions on concrete properties and microstructural characteristics are reviewed, and technical approaches such as appropriate raw material compositions and curing regimes are explored. Moreover, the environmental
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· In concrete, a first patent on the use of asbestos fibers was filed in 1902. Steel fibers were introduced around 1923 whereas glass fibers were introduced around 1950 when the harmful character of asbestos was recognized and alkali-resistant glass fibers were developed. Polymer fibers followed immediately.
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· The cement manufacturing process involves the extraction and processing of raw. materials, such as limestone, cla y, and shale, which are t hen heated in a kiln at high temperatures to form
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The mining of sand, a non-renewable resource. Context-Sand and gravel are used extensively in construction for the preparation of concrete as well as for other applications such as glass, electronics or aeronautics. These are mined in coastal areas, where it can cause problems.
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· The particle size distribution of raw materials tested by a laser diffraction (Mastersizer 3000, Malvern, UK) was shown in Fig. 1. RFP has similar particle size distribution to cement while the RCP and RMP have smaller volume of particle less than 10 μm, means that cement and RFP have finer particles than RCP and RMP.
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· The Indian Cement Industry, well recognised for its energy and resource efficient operations, has been a frontrunner in making use of advanced technology and sustainable business practices. Responsible resource management has been embedded across its value chain, well beyond mining practices alone. Despite increasingly high
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· Compared with normal concrete and bricks, Autoclaved Aerated Concrete (AAC) consumes less energy [1] and raw materials [2], [3]. Due to this fact and primarily given its excellent thermal insulation [2] , [4] , [5] , AAC has great potential for use as an element in the buildings of the future.
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· Then, various materials used in developing the 3D printing concrete, including geopolymer cement and supplementary cementitious materials, and their effects on the 3DPC properties are discussed. After that, mix design methodology currently adopted in 3DPC and the influence of ingredients are highlighted.
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· The dissolution of mining wastes has been optimized for subsequent carbonation [299]. The reaction follows Eq. (14) where CaO in mining wastes reacts with HCl to extract Ca 2+ as a CaCl 2 solution
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· The cement industry is facing numerous challenges in the 21st century due to depleting natural fuel resources, shortage of raw materials, exponentially increasing cement demand and climate linked environmental concerns. Every tonne of ordinary Portland cement (OPC) produced releases an equivalent amount of carbon dioxide to the
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· The raw materials ratio is based on the sample CK5, and the ratio of water to the material is 0.58. The additional amount of aluminum powder, activator, and suspension dispersant is 1.5% of the total basis material and different concentrations of the additional amount of the above ingredients such as 0.05%, 0.1%, 0.15%, 0.2%, 0.25%
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· Therefore, it is necessary to control the curing process and raw material compositions of steam-cured concrete to prevent deformation or even cracking of concrete. (3) Delayed ettringite formation (DEF): It is generally believed that ettringite tends to be unstable above 70 °C, and it can be present in cement slurries up to 90 °C when
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· Although the ongoing discussion on cement and concrete sustainability is mostly focused on CO 2 emissions, the management of raw materials used for construction also deserves the attention of the scientific community and industry.
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6 · Clear Advanced. The principal ingredients that make up the concrete mix are: cement, fine aggregate, coarse aggregate, water, chemical admixtures, and mineral admixtures. Concrete used in construction may also contain reinforcing bars, welded wire fabric (wire mesh), and various reinforcing fibers. The quality of the ingredients, their
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· The Critical Raw Materials Act (CRMA) is an essential regulatory framework designed to address the pressing challenges faced by the European Union (EU) in the strategic sectors of decarbonization, digitalization, and aerospace and defense. It aims to tackle the lack of secure and sustainable access to critical raw materials (CRMs) by
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· of road and bridge projects can be guaranteed in essence. In the actual construction process, the proportion of raw. materials in the concrete will directly affect the quality of. the nal concrete
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· Cement-Extraction, Processing, Manufacturing: Raw materials employed in the manufacture of cement are extracted by quarrying in the case of hard rocks such as limestones, slates, and some shales, with the aid of blasting when necessary. Some deposits are mined by underground methods. Softer rocks such as chalk and clay can be
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· Abstract. The mining industry manages large volumes of tailings, sludge, and residues that represent a huge environmental issue. This fact has prompted research into valorization of these wastes as
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· Thus, a low-strength concrete material can be obtained. This result agrees with Ullah et al. [10] and Naceri and Hamina [11] . These authors recommend less than 10 % replacement of ceramic residues to avoid the drop in resistance due to the deceleration of the pozzolanic reaction.
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Due to be published later this month by the UN's International Resource Panel, it highlights how global consumption of raw materials, having increased four-fold since 1970, is set to rise by a
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· Materials play a fundamental role in any branch of civil engineering. From ancient times to the present day, society has required enormous amounts of construction materials, which implies an excessive exploitation of the natural environment. The present research
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It can be seen that direct effects were by far most significant in Indonesia. Around 1,900 km² were lost directly due to mining activities in the past two decades, making up for 58% of forest loss in the tropical biome caused by industrial mining. Almost half of the losses in Indonesia occurred from 2010-2014.
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· The introduction of dispersed mineral additives has a beneficial effect on many properties of concrete. This is either due to the physical effect, which means that small particles usually have a finer granulometric composition than Portland cement and present themselves as a “microfiller”. On the other hand, this may be due to their
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· The construction sector contributes significantly to the production of greenhouse gases and thus to climate change. This study aims to quantify the environmental performance of selected bearing constructions with special regard to their climate change contribution and resource depletion. Environmental impacts were
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DOI: 10.1016/j.jobe.2022.104676 Corpus ID: 249109496 A comprehensive review on dry concrete: Application, raw material, preparation, mechanical, smart and durability performance @article{Shao2022ACR, title={A comprehensive review on dry concrete
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· recycled aggregates, which were cured at 20 C in a water bath [8]. However, with 100% of RCA there was a reduction in by 20-25% as compared to NA, at 28 days. with the same effective w /c of 0.5
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· The CRMA names 34 critical raw materials and 17 strategic raw materials. The agreement sets benchmarks for domestic extraction (10%), processing (40%) and recycling (25%). These benchmarks will put increased pressure on the mining and processing industry to ramp up their domestic production capabilities and revisit their
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· They replaced a certain amount of cement in 0%, 10%, 20%, and 30% with fly ash and coarse aggregate with industrial. waste product of coconut cover fractions in finding the mechanical. and
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Study on Quality Control of Concrete Raw Materials in Road and Bridge Construction Suqin Han* Xiuyong Ni Ruimin Huang Shandong Transport Vacational College, Taian, Shandong, 271000, China
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Trituradora de piedra vendida por proveedores certificados, como trituradoras de mandíbula/cono/impacto/móvil, etc.
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