Also, this study investigated the use of mining process tailings in concrete production instead of fine aggregate and cement. Thus, it was emphasized that evaluations should not only be made according to the mechanical properties of the concrete with tailings but also concrete's environmental characteristics should be taken into …
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The study aims to address the depletion of river sand by integrating sea sand as a fine aggregate in the production of Self-Compacting Concrete (SCC) through a …
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The cost of 1 m³ of control concrete is 53.68 USD and total replacement of sand with SFS-M is 48.62 USD. The SFS-M concrete shows a cost reduction of 9.5%. Replacement of natural sand with SFS-M reduces the cost of concrete production, and the concrete meets all requirements for its use as hexagonal concrete blocks for light traffic.
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2.3. Specimen preparation. The mixing and preparation of FRMSC was carried out in accordance with the standards GB/T14902-2012 [42] and JG/T472-2015 [43].To ensure a homogeneous structure and alleviate fiber agglomeration, all concrete mixtures were blended using a mixer according to following procedures: (1) Dry …
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Sand mining is the extraction of sand and gravel from rivers, lakes, oceans and beaches for construction materials. It is a global challenge that threatens …
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Therefore, sea sand can potentially replace river sand in concrete applications. If seawater and sea sand are used to replace freshwater and river sand, it will greatly ease the current situation of resource tension in China. Since Teng et al. [2] first advocated that FRP bars could be used for seawater and sea sand concrete structures
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Section snippets Materials and mixing proportion. P.O 42.5 ordinary Portland cement with specific surface area of 326.7 m 2 /kg and density of 3.09 g/cm 3, class F fly ash with a density of 2.08 g/cm 3, crushing limestone (coarse aggregate) with the continuous gradation of 5–25 mm and manufactured sand and dredged sand as fine …
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1. Introduction. In recent years, as the scale of China's infrastructure construction continues to expand, concrete has become a widely used construction material [].In 2020, China produced 2.5 billion m 3 of concrete, which consumed nearly 1.65 billion tons of sand and gravel, including a large number of natural river sand (RS) …
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Incorporation of steel fibers to improve the defects of manufactured sand concrete (MSC) has received a great deal of attention, while the fracture mechanism of the MSC by volume fraction of steel fibers (V f) has been less studied.To investigate the effects of steel fibers on the fracture characteristics of the MSC, three-point bending tests …
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Recycled concrete with manufactured sand (RCM) is a type of recycled concrete that uses manufactured sand as fine aggregate, and there have been limited reports on the investigation of its high temperature performance in the construction industry.
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In the marine environment, concrete in both submerged zone and non-submerged zone could be attacked by seawater. To study the deterioration of sea-sand concrete partially submerged in seawater, an accelerated test with simulated marine environment was designed for seawater and siliceous sea-sand concrete (SSC), coral …
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With the proposed mix ratio design method, the different grades C30, C40, and C50 of manufactured sand concrete were designed. Furthermore, the properties …
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The influence of concrete pore distribution on the mechanics and water transport characteristics of sea-sand concrete was analyzed. The volume ratio and pore volume ratio of each solid composition in concrete was studied. ... Mining Sci. Technol., 21 (1) (2011), pp. 123-127, 10.1016/j.mstc.2010.07.003. View in Scopus Google Scholar …
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Table 3 shows the mix proportions of the CRSC, where CRSC-30 denotes coral reef sand concrete with strength grade C30, CRSC-PF refers to coral reef sand concrete with strength grade C30 and polypropylene fibers at a volume rate of 0.10%, and CRSC-BF denotes coral reef sand concrete with strength grade C30 and basalt fibers …
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blocks with characteristics of resistance and offering possible thermal comfort, besides contributing as an option for a destination for these mineral and agro-industrial wastes. Keywords Composite · Lignocellulosic bers · Mining wastes · Quartzite · Block characterization Introduction Cement composites are mineral binders and may contain
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The load-bearing characteristics and failure mode of CFSTCPs in the sand-rock composite ground are revealed through model tests. • The dimensionless relationship between ζ b and l r and σ c is derived to evaluate the critical rock-socketed length.. An empirical method for calculating the ultimate bearing capacity of CFSTCPs in …
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Types of Sand & Classification of Sand. Followings are the classification of Sand: Based on the grain size of the particle, sand is classified as Fine Sand(0.075 to 0.425mm), Medium Sand(0.425 to 2mm), and Coarse Sand(2.0 mm to 4.75mm) Based on origin, sand is classified as Pit sand, River sand, Sea sand, and manufactured sand.
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Section snippets Spraying materials and technology. The standard P.O 42.5 cement produced by China United Cement Group Co., Ltd. was used in the experiment, and the quality met the requirements of GB 175-2020 Common portland cement[23].The fine aggregate is river sand with a fineness modulus of 2.89, the water content of sand …
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Mix design and characteristics evaluation of high-performance concrete with full aeolian sand based on the packing density theory ... With the westward movement of highway construction in China and the gradual increase of restrictions on aggregate mining, high-quality construction materials are scarce in desertification areas, which …
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[Show full abstract] sand (quarry, river, mining and marine sand) with two conventional binders (PEN 50/60 & 80/100) and four polymer modified bitumen (PM1_76 & PM1_82 and PM2_76 & PM2_82) were ...
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The reduction in density of concrete made with waste foundry sand is expected, due to the physical characteristics of waste foundry sand which are fineness and porous. The more water absorption and fineness of the waste foundry sand (WFS) enhances the water requirement of concrete due to water absorption, which leads to …
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1. Introduction. Lightweight concrete (LWC) has been used for structural purposes for many years. The density of LWC typically ranges from 1400 to 2000 kg/m 3 compared with that of 2400 kg/m 3 for normal weight concrete (NWC). Some of the techniques used for producing LWC include using natural lightweight aggregates such …
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2.3.2. Dry and wet cycle tests. The DWCs test was based on the Chinese standard (GB/T50082–2009). The ASC with different carbonation times was soaked in a NaCl solution of 3.5% for 15±0.5 h, and the specimens were immediately put into an oven (80±5) ℃ to dry for 6 h and naturally cooled for 2 h after removing the specimens and …
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Wang et al. [34] investigated the radiation resistance performance of concrete prepared by peridotite containing 12.95 wt% crystal water, which was tested using a 241 Am-Be neutron source. It has been shown that the neutron decay rate in ordinary concrete is almost half that of peridotite concrete under the same thickness [34].
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Developing sustainable sand can solve environmental issues caused by excessive river sand mining. For this purpose, four types of sustainable sand have been developed. ... A comparative study of strength and durability characteristics of concrete and mortar admixture by bacterial calcite precipitation: a review. Mater. Today.: Proc. (2023 ...
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This article reviews the geological aspects of aggregates, their production, consumption, and environmental impacts. It covers the main types, sources, and modes …
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The mining industry produces a large amount of stone waste and tailings, which poses a threat to the environment. ... benefits of mine tailings-based geopolymer composites for building applications utilizing mine tailings as suitable concrete material. This review paper also highlights knowledge gaps that must be overcome to progress …
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Discover how sand mining is a growing problem, exhausting a finite resource at a great cost to the planet. ... Sand is the foundation of human construction and a fundamental ingredient in concrete, asphalt, glass and other building materials. But sand, like other natural resources, is limited and its ungoverned extraction is driving erosion ...
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1 A sustainable solution to excessive river sand mining by utilizing by-products in concrete manufacturing: A state-of-the-art review Hong Lich Dinh, Jiarui Liu, Dominic E.L. Ong, and Jeung-Hwan Doh*
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Here, we present a new perspective on global sand sustainability that shifts the focus from solely evaluating local impacts of sand mining to understanding the entire sand-supply network (SSN) of a region as a …
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