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yes,up to one year. However the rate again of strength is very slow.
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Why is the 28-days compressive strength of concrete generally specified?
It is attributed to two reasons: 1. Strength of concrete grows faster in initial days and this process of gaining strength slow down with time. This can be said as stabilization in value of gained strength of concrete. After approximately 20 or some more days, strength value get stabilize and does not change too much with time. Therefore, compressive strength is taken after approximatley 3 weeks time. 2. These tests have to performed practically and date record is needed to be maintained. Therefore, if test duration is a multiple of 7 (7 weekdays) then it is more easy to remind. It is the reason we have 28=7x4 days to note down compressive strength of concrete. for ex: if we start test on monday then we know that after 4 weeks on same time on monday we can finish the compressive strength test.
Concrete cure time?
In anarid region, concrete placed as a road slab or roof slab gets dried up in a very short time, say within 2 hours.This condition should be maintained for 24 hours or at least till the final setting time of cement at which duration the concrete will haveassumed the finalvolume.Normally curing is done for 28days at 90% of strength gain is achievedUntil maximum design strength is achieved (should be 28 days): Concrete does not gain strength by "Drying out". It gains it through a process known as hydration. The road slabs used as an example in the first post will still undergo hydration once water makes contact with the concrete. (rain). k.k
What is the full form of CTD bars?
CTD Bars - Cold Twisted Bars are made by twisting the bars after hot rolling. Having various advantages,Having various advantages, CTD Bars differ from the TMT Bars in: DuctilityCTD Bars derive their strength from hardening where strength gain results in decrease of ductility. Decreased ductility has an adverse effect on the ease of fabrication, earthquake resistance etc. Resistance from Rust, Corrosion and FireSince CTD Bars are made after hot rolling, they have less resistance from rust as well as fire. AffordableCTD Bars are quite affordable for using in construction. But are less economical than TMT Bars. BendabilityCTD Bars are flexible after the hot rolling process they are manufactured from. However, TMT Bars precede over them in case of bending and re-bending ability.R.Mohanakrishnan=== ===
What is the civil engineers income?
The income of a civil engineer can vary depending on the area. A civil engineer in New York will have a higher income than one in Iowa. Average yearly income for civil engineers in New York can be as much as $97,000 and in Iowa can be as much as $77,000.
Do you need to be an architect to design houses and sell the floor plans?
By definition, anyone who designs floorplans for residential, commercial and/or industrial buildings is an architect. Most people attend colleges or universities prior to beginning a career as an architect, however as with many things the skills required for such a vocation can be learned on one's own. Certification, training and experience will certainly help one gain the knowledge required. The passion for learning and creation will ultimately propel one into a successful career as an architect.
Which type of concrete should you use when it must reach its design strength in about 28 days?
concrete made upof ordinary portland cement gain strength in 28days
Why 7 days compressive strength is concider?
concrete strenght gain at first 7 days much increase so we consider 7days strenght
Why is the 28-days compressive strength of concrete generally specified?
It is attributed to two reasons: 1. Strength of concrete grows faster in initial days and this process of gaining strength slow down with time. This can be said as stabilization in value of gained strength of concrete. After approximately 20 or some more days, strength value get stabilize and does not change too much with time. Therefore, compressive strength is taken after approximatley 3 weeks time. 2. These tests have to performed practically and date record is needed to be maintained. Therefore, if test duration is a multiple of 7 (7 weekdays) then it is more easy to remind. It is the reason we have 28=7x4 days to note down compressive strength of concrete. for ex: if we start test on monday then we know that after 4 weeks on same time on monday we can finish the compressive strength test.
What is mean by m20 of grade concrete?
it is concrete mix which gain strength 20kn/mm2 in 28 day of curing....
Concrete cure time?
In anarid region, concrete placed as a road slab or roof slab gets dried up in a very short time, say within 2 hours.This condition should be maintained for 24 hours or at least till the final setting time of cement at which duration the concrete will haveassumed the finalvolume.Normally curing is done for 28days at 90% of strength gain is achievedUntil maximum design strength is achieved (should be 28 days): Concrete does not gain strength by "Drying out". It gains it through a process known as hydration. The road slabs used as an example in the first post will still undergo hydration once water makes contact with the concrete. (rain). k.k
What is the compressive strength of M35 concrete at 14 days?
35N/mm2 the above answer is terrible. at 14 days there is no guarantee of what the strength will be, as strength gain is rapid with pue OP it will tend t be greater than 50% of the target characteristic strength; however, with any pozzolans in the mix (e.g. PFA/GGBA) the strength gain over time is slower and can be espected to achieve greater strengths than that of pure OPC the question is too vague to answer. the mix design is pivotal in calculating strength
Does vacuum dewatered concrete requires curing?
Yes, the vacuum dewatered concrete requires curing in order to gain its strength.The concrete is cured for 28 days.
What is difference between 43 and 53 grade opc cement?
43 grade OPC Cement it denotes the compressive strength of concrete in 43 Mega pascals will attain in 28 days. it is normally used for pavements, Non RCC structures and which are not important for initial strength. where as 53 Grade OPC Cement it denotes the compressive strength of 53 Mega Pascals will attain in concrete with the 28days, and it is used for RCC strengths and which are important to gain initial strength.
The difference between setting and hardening in cement?
SettingSetting begins to occur after the concrete is mixed and even before pouring. The cement in the concrete begins to stiffen after mixed with water. The concrete is beginning to change from liquid form to solid form. During the setting process, the concrete does gain strength, which is the beginning of the hardening process. When the water ingredient is added to the concrete mix, the concrete is still pliable and flexible, sort of a paste. There is two stages of setting: initial and final setting. Initial setting is when the concrete loses it flexibility and begins to harden. Final setting is when the concrete can sustain some load, but still has some moisture within the mixture.HardeningHardening of the concrete is the stage when the mixture gains strength. The cement ingredient begins to attach itself to the aggregate as the water dries off the mixture. The hydration of water is what starts the hardening process. It generally takes five to seven days for the concrete to complete the hardening process. The easiest way to increase the strength of concrete is to add cement to the mixture. The more water used in the mixture, the weaker the concrete and it will also delay the hardening process. Once the concrete has hydrated all the water from the mixture, the hardening process is complete and the concrete is as strong as it will get.
How does the fineness affect the time of setting?
Setting begins to occur after the concrete is mixed and even before pouring. The cement in the concrete begins to stiffen after mixed with water. The concrete is beginning to change from liquid form to solid form. During the setting process, the concrete does gain strength, which is the beginning of the hardening process. When the water ingredient is added to the concrete mix, the concrete is still pliable and flexible, sort of a paste. There is two stages of setting: initial and final setting. Initial setting is when the concrete loses it flexibility and begins to harden. Final setting is when the concrete can sustain some load, but still has some moisture within the mixture. Hardening
How long should a concrete pad cure before removing forms?
Most of the time it comes off the next day. Some will strip it the same day. I just think that is too soon. Can depend on the mix design of the concrete and what type of cement is used. Can range from 5min to days. Concrete at precast plants that make sewer structures will remove the forms 5min after because of the mix design (0 slump / rapid setting / high strength gain). Bridge girders will be striped 12 - 24 hours after concrete has been placed (high early strength gain cement). Other form work in construction is based of cement type used in the mix design of the concrete or contractors decisions (1 or more days).
What is curing why need to curing in buildings?
Curing in buildings is a process that is keeps freshly poured concrete from drying. It is kept at a certain temperature to keep it moist. Curing in buildings is important because it gives concrete what it needs to gain strength properly.
