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Conclusions. The concrete without any retarder gives target compressive strength and flexural strength, up to retempering time 45 min. The concrete with 0.2 % retarder shows target compressive strength and flexural strength, up to retempering time …
Excess moisture can adversely affect the performance of concrete made using the sand. To find moisture content, take a sample of the sand and dry it out completely in an oven. Then, compare the wet and dry weights. The difference between the two divided by the initial wet weight gives you the moisture content percentage. This …
concrete made by using manufactured sand. Usually the retempering process is there with normal and ready mixed concrete; hence an attempt is made to check the com-pressive …
4.1 Test results on fresh concrete. The workability test results carried out by using slump, compaction factor, flow and vee bee degree with different percentage replacement of natural sand by manufactured sand and 20% cement replaced by different pozzolanic materials are shown in Tables 1, 2, 3 and 4 respectively and the variation of …
Date: 2/8/2024. Seawater-Mixed Lightweight Aggregate Concretes with Dune Sand, Waste Glass and Nanosilica: Experimental and Life Cycle Analysis. Publication: IJCSM. Date: 11/30/2023. Behavior of Engineered Cementitious Composites with Expanded Glass for Thermal Applications. Publication: Materials Journal.
The effects of using recycled concrete aggregates instead of natural aggregates in concrete are: reduction in compressive strength up to 25%; reduction in modulus of elasticity up to 30% ...
Machine-made sand instead of natural sand has become an inevitable choice for the sustainable development of the concrete industry. Orthogonal experiment and grey correlation analysis were used to investigate the performance of machine-made tuff sand concrete. The optimal concrete mix ratio of machine-made sand was …
Application of used-foundry sand in concrete will lead to diversion of large amounts of used-foundry sand from land filling to manufacturing of concrete. 2. Literature review. Limited studies have been reported on the use of foundry sand in concrete and concrete related products like bricks, blocks and paving stones.
75% replacement of M sand in concrete (M25) 9. Replacement of M sand by 25% with naural sand decrease Flexural strength up to 8.22% for 28 days 10. Replacement of M sand by 50% with naural sand increase Flexural strength up to 27.94% for 28 days 11. Replacement of M sand by 75% with naural sand increase Flexural strength up to 40% …
In this study, effects of prolonged mixing and four different retempering processes on some properties of fresh and hardened concrete, such as temperature, …
proportion (kg/m3) was shown in Table 2. Machine-made sand was used to replace river sand with. 20%, 40%, 60%, 80%, and of sand mass respec tively. The total amount of river sand and. machine ...
Concrete is made up of three basic components: water, aggregate (rock, sand, or gravel) and Portland cement. Cement, usually in powder form, acts as a binding agent when mixed with water and aggregates. This …
Concrete is made by combining the Portland cement with water to create a paste that coats the aggregates and bonds together and gains strength as it hardens. The process involves several steps: After good old-fashioned water, concrete is the second-most used material in the world. There are many different types of concrete but they all …
In 2011, approximately 70 million tonnes of fine aggregate was used in producing ready-mixed concrete in Japan, with desalted sea-sand accounting for 12.2% (8.54 million tonnes), river sand 13.9%, mountain sand 40.2% and …
Arbitrary Method of Proportioning Concrete. The general expression for the proportions of cement, sand and coarse aggregate is 1 : n : 2n by volume. 1 : 1 : 2 and 1 : 1.2 : 2.4 for very high strength. 1 : 1.5 : 3 and 1 : 2 : 4 for normal works. 1 : 3 : 6 and 1 : 4 : 8 for foundations and mass concrete works.
In this project the natural sand was replaced with m-sand by 50% proportions.Plain concrete needs for a minimum period of 28days curing to attain good strength.Then the optimum replacement of ...
The results indicated that a marginal increase in strength and durability properties of high performance concrete by addition of manufactured sand as a complete replacement of natural sand ...
Concrete compositions made of light-coloured CC after being crushed in a ball mill and sifted on a normative sieve set to obtain a fraction of 2/16 mm were employed. Control tests of natural radioactive isotope concentrations for CC from the combustion of fine coal were carried out in an external laboratory by means of the gamma spectrometry ...
Usually the retempering process is used with normal concrete or with ready mixed concrete; an attempt is made to check the compressive and flexural strength of normal retempered concrete with an ...
In this work, an attempt is made to study the strength characteristics of retempered concrete made by using manufactured sand. Usually the retempering process is there …
1. Sea Sand. The particle size is too fine and too uniform for good class work. Sea sand used in its natural state causes corrosion to steel reinforcement due to the presence of salts. The higher percentage of salts also increase the setting time of the concrete, retards hardening, and may cause efflorescence.
prepare sand concrete instead of fine aggregate, and the results showed that the addition of iron tailings can produce high performance sand concrete; Ivan Francklin Junior [17] used quartzite tailings to produce high-performance concrete; Siddique [18] think waste foundry sand could be very conveniently used in making …
Retempering is done on the mortar board by the mason, usually by dribbling water into the mortar pile, then reworking with a trowel or shovel. This replaces water lost by evaporation. It keeps the mortar plastic so that units can be laid and positioned in it. To those familiar with concrete, adding water seems like it ought to be prohibited.
Usually the retempering process is used with normal concrete or with ready mixed concrete; an attempt is made to check the compressive of normal retempered concrete with an addition of retarder in ...
Before we dive into the details, let's recap the basic ingredients of concrete: Water. Fine aggregate (natural sand particles) Coarse aggregate (gravel, crushed stone, recycled concrete) Cement. Optional: admixtures – special chemicals to tweak the mix's properties. These ingredients are as down-to-earth as they come.
In this paper an attempt is made to study the strength characteristics of concrete containing super plasticizer and retarder at retempering time of 15 min up to 90 min. The study also …
Concrete Calculator. Our online tools will provide quick answers to your calculation and conversion needs. On this page, you can calculate material consumption viz., cement, sand, stone gravel for the following concrete mix ratios - 1:1.5:3, 1:2:4, 1:3:6, 1:4:8, 1:5:10. Once, the quantities are determined, it is easy to estimate the cost of a ...
Influence of retempering on properties of concrete made with manufactured sand and industrial waste. K. Mane, Abhay. M. Joshi, +1 author. K. Prakash. Published …
But first, let's take a look at how concrete is made: 1. All-Purpose Concrete. Out of all the types of concrete, all-purpose concrete is the most popular in the U.S. It is made from cement, air, water, sand, and gravel. The ratios are 10% cement, 20% air and water, 30% sand, and 40% gravel. It is mainly used for exterior residential jobs.
and impact strengths for retempered concrete made by 20% substitute of cement by silica fume with additional 5% cement and water are increased up to 60 min of retem-pering …
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