- منطقة بودونغ الجديدة ، شنغهاي ، الصين .
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The paper examined sand and gravel mining activities both on land and the rivers as a business venture in Minna emirate council of Niger state, Nigeria. It identified various stakeholders in this business as: the landlords of the quarries, the local government authorities and the miners among others. It further looked at what each stakeholder …
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River sand concrete attained higher densities than quarry dust concrete for all ages of curing. The higher density of river sand concrete can be as a result of higher density of the river sand in relation to the quarry dust. The density of river sand concrete and quarry dust concrete are within the nominal value of 24 kN/m 3 (i.e. 2,446 kg/m 3
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However, the concentrations of radionuclides in sediments varied with locations, since the river bottom exhibit large variations in chemical and mineralogical properties and rare-earth elements (Ramasamy et al., 2014). Sediment deposits at river bottom most often contain sand and gravel of different grain sizes (Isinkaye and …
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The widely used raw materials in a concrete are cement, fine aggregate, coarse aggregate and water and in which river sand is used as fine aggregate and it is of prime importance in mix design. Due to increasing demand of river sand, river erosion and other environmental issues have led to scarcity of river sand.
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Quarry dust has been proposed as an alternative to river sand that gives additional benefit to concrete. Quarry dust is known to increase the strength of concrete over concrete made with equal quantities of river sand, but it causes …
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In Nigeria and most other countries, river sand is traditionally used as fine aggregate in concrete production. The continuous mining of sand from our ... with partial replacement of river sand with quarry dust produced better compressive strength than conventional concrete up to 40% replacement level – a
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The extraction of sand and gravel from river, stream terraces, floodplain and channels, conflicted with other resources such as fisheries, recreational functions and with the stability of the river channels. ... In Luku area of North Central Nigeria, sand and gravel mining has been going on at a large scale. Results of field work shows that ...
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As a result, quarry dust and river sand are suggested as construction materials for making concrete, and can be used to replace river sand up to 30% of the time to achieve the needed compressive strength of not less than the standard Keywords: River sand; Quarry dust; Ordinary Portland Cement; Compressive strength DOI: 10.7176/JEES/11-9-06 ...
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