What is the time of initial setting and final setting of concrete

Depending on the construction situation, a coagulant or retarder will be used.

National standard: the initial setting time shall not be less than 45 minutes, and the first spring is 1 3 hours;

National Chi Xianjia standard: the final setting time shall not be later than 12 hours, generally in 5 8 hours.

The guarantee according to the national standard is correct haha.

The initial setting of concrete and the final setting time are related to the mix ratio of concrete slippery dry soil and the temperature of the song, the initial setting of cement is not earlier than 45 minutes, and the final setting is not later than 600 minutes or 900 minutes of wild covering.

Initial setting: there is no precise time, it is greatly affected by the mix ratio, admixture, volume shape, location, as well as the season and the climatic conditions of preparation, the winter cracking socks are about 6 8 hours, and the summer is about 2 3 hours.

Final coagulation: It is also roughly the same as the conditions that determine the initial setting time, but it is generally within 12 hours.

Initial coagulation: There is no precise time Li Dong matching, which is greatly affected by the mix ratio, admixture, volume shape, location, as well as seasonal and climatic conditions, generally about 6 8 hours, and the final condensation which refers to: It is also roughly the same as the tremor that determines the initial coagulation time, but it is generally better about 2 hours after the initial condensation.

Depending on the construction situation, pre-setting agents or retarders are used.

National standard of slag: the initial setting time shall not be less than 45 minutes, and the general suspicion of the beam limb is 1 3 hours;

National standard: The final setting time shall not be later than 12 hours, generally in 5 8 hours.

The guarantee according to the national standard is correct.

Different setting times of concrete with different disadvantages, it is best to test it according to the penetration resistance meter, or observe a group of concrete forming chain sails (when adding admixtures to the concrete, it will have an impact on the setting time).

Test it yourself A simple penetration resistance meter solves the problem.

The mix ratio is related to the temperature, and the cement initial setting time is related.

According to the requirements of national regulations, the initial coagulation should be after hours, and the final condensation should not be greater than 12 hours. However, the specific time is not fixed, because the properties of cement and infiltrating agent are not the same, so this time can only be estimated. Generally speaking, the initial coagulation is about 1-4 hours, and the final coagulation is about 5-10 hours.

When the cement is mixed with water, the hydration reaction occurs immediately on the surface of the cement particles, as shown in Figure 1, and the colloidal hydration products generated accumulate on the surface of the particles to form a hydrate film, which slows down the chemical reaction, and the cement slurry at this stage is both fluid and plastic (Fig. 1(b)).

Preparation. Before measuring the coagulation time, it is necessary to check whether the sliding part of the instrument can slide freely in the bracket, and at the same time check that when the test rod is lowered to the surface of the slurry, the pointer should be the zero point of the calib, otherwise it should be adjusted. Before measuring the coagulation time, the consistency test rod should be removed;

Replace it with a test needle, and check whether the pointer is zero when the test needle is in contact with the top of the round mold, otherwise it should be adjusted. Before each measurement, the instrument should first be placed vertically and steady, and it should not be operated in an environment with obvious vibration. After each measurement, the working surface of the instrument should be wiped clean and oiled to prevent rust.

The surface of the slide bar should not be bruised or rusted.

The initial setting time of concrete beams, slabs and columns is 8 h 12 h, and that of large-volume concrete is 12 h 15 h. Before the initial setting of the concrete of the protective layer of the exposed surface, the covering should be rolled up, and the surface should be rubbed with a trowel at least twice to make it smooth and covered again, and it should be noted that the covering should not directly touch the concrete surface until the concrete is finally set.

The initial setting time of concrete is generally two to three hours, and the initial setting time is related to the variety of cement, as well as the ambient temperature and proportion. If you want the initial setting time to be slower, you can add a retarder.

Question: How long does it take for concrete retarder to reach the initial setting, and how long does it have an impact on the strength of concrete?

Answer: It takes about 8 to 10 hours for final setting and 28 days for concrete to set completely. Concrete solidification time is related to its quality, surrounding temperature, curing, concrete solidification usually needs to go through the initial setting, and then can be finalized, after adding water to stir, it will gradually solidify, asking questions more than how long will have an impact on the strength of concrete.

The initial setting time of concrete is about one hour.

The final setting time is not more than three hours, which is related to the cement variety and temperature, mainly depending on the cement test report.

Different setting times of concrete with different mix ratios are best tested according to the penetration resistance meter, or a group of concrete is formed to observe.

When admixtures are added to concrete, it will have an impact on the setting time).

Concrete, abbreviated as "concrete (tóng)": refers to the general term for engineering composite materials that are cemented into a whole by cementitious materials. The word concrete usually refers to the use of cement as cementitious material, sand and stone as aggregates; Cement concrete, also known as ordinary concrete, is widely used in civil engineering engineering when it is mixed with water (which can contain admixtures and admixtures) in a certain proportion and is mixed to obtain cement concrete.

The French engineer Ernabic was inspired to apply the material to houses when he saw Monier's pots, bathtubs, and cisterns made of barbed wire and concrete at the Paris Exposition in 1867.

In 1918, Abram published the famous theory of the water-cement ratio to calculate the strength of concrete. Reinforced concrete began to become an important material to change the landscape of this world.

The initial setting time of concrete without admixtures (retarders) is the initial setting time of cement. The initial setting time standard for the six types of cement in the general cement standard GB175-2007 is no earlier than 45 minutes. Generally, the warm temperature is about 1 hour.

In this standard, the final setting time of Portland cement does not exceed 10 hours, and the final setting time of the other five types of cement does not exceed 10 hours.

The initial setting time still depends on the specific situation of the concrete, generally speaking, it is about an hour. However, the concrete used in high-rise buildings generally takes about 10 hours, because the admixture of retardation such as pumping agent will be added to it.

See if you add retarder, no concrete.

The initial setting time is about the initial setting time of cement, with the addition of retarder, generally in 4-10 hours, and the final setting in 10-15 hours.

Summary. The initial setting time refers to the time when the concrete begins to solidify, that is, the time when the moisture in the concrete begins to gradually solidify, and the concrete begins to become less likely to flow. The initial setting time is usually about 3-5 hours after the concrete is poured, and the specific time depends on the concrete mix ratio, temperature, humidity and other factors.

The final setting time refers to the time when the concrete is completely solidified, that is, the time when all the moisture in the concrete is solidified and the concrete reaches its final strength. The final setting time is usually about 24 hours after the concrete is poured.

The initial setting time refers to the time when the concrete begins to solidify, that is, the time when the moisture in the concrete begins to gradually solidify, and the concrete begins to become less likely to flow. The initial setting time is usually about 3-5 hours after the concrete is poured, and the specific time of the high sail depends on the concrete mix ratio, temperature, humidity and other factors. The final setting time refers to the time when the concrete is completely solidified, that is, the time when all the moisture in the concrete is solidified and the concrete reaches its final strength.

The delayed final setting time is usually about 24 hours after the concrete is poured.

During the initial and final setting of concrete, the following points need to be noted:1During the initial setting period, the concrete is still in a flowing state, and it is necessary to avoid the vibration and impact of external forces, so as not to affect the uniformity and strength of the concrete of the mixed mold.

2.During the final setting period, the concrete has begun to harden, and it is necessary to avoid vibration and impact of external forces, so as not to affect the strength and durability of the concrete. 3.

During the initial and final setting of concrete, it is necessary to cure the concrete and maintain the appropriate humidity and temperature to promote the hardening and strength development of the concrete.

Dear, glad you asked! Concrete is an artificial material that is hardened by mixing cement, aggregates, powders, and an appropriate amount of admixture. In the process of concrete processing, the initial setting time and the final setting time are two very important parameters.

The initial setting time refers to the time from the addition of cement to the time when the slurry begins to lose its fluidity. The initial setting time of different types and grades of cement may be slightly different, generally speaking, the initial setting time is 2-4 hours. 2.

Final setting time: refers to the curing time required for the concrete slurry to become solid enough to make structural changes to reach the predetermined strength standard. The final setting time refers to the curing time required from the addition of cement to the time when the concrete is fully hardened and reaches its design strength.

The final setting time of different types and grades of cement will also vary, generally speaking, the final setting time is 24-48 hours. It should be noted that the initial and final setting periods of concrete should be reasonably controlled during construction and adjusted according to the specific situation of the canopy. For example, in a hot and dry environment, the hydration rate of concrete is accelerated, and the initial setting time may be shorter; In cold and humid environments, the hydration rate of concrete slows down, and the initial and final setting times may be extended.

Therefore, sufficient calculations and considerations need to be made before construction.

The initial setting time of concrete is 1-6 hours, and the final setting time is 3-24 hours. The initial and final setting time of concrete is not fixed, and there is a large time range variation, because the initial and final setting time of concrete is related to admixtures, cement types, ambient temperatures, etc.

For example, ordinary cement for concrete.

The initial setting time is not less than 45 minutes, and the final setting time is usually not more than 10 hours. If the concrete is made of Portland cement.

The initial setting time is not less than 45 minutes, and the final setting time is usually not more than an hour. Under normal circumstances, the initial and final setting time of concrete in summer will be shorter than that in winter.

The use of admixtures in concrete will shorten or delay its initial and final setting time, for example, in a 20-degree environment, the concrete will be initially set in about 5 hours and finally set in about 6 hours. If it is mixed with a high-efficiency retarder, it will initially coagulate in about 12 hours and finally coagulate in about 16 hours.

The concrete configuration should not be left for too long after it has been mixed evenly, for example, in the summer when the construction temperature exceeds 30 degrees, we need to use up the concrete mortar within an hour. If the concrete mortar is placed for too long and solidifies, it will be mixed and poured with water, which will affect the quality of the concrete components. The initial setting of concrete mortar can no longer be poured.

Summary. The initial setting time of concrete is generally 2-4 hours, which means that the concrete begins to harden, but can still be used for vibrating, pouring and surface treatment.

The initial setting time of concrete is generally 2-4 hours, which refers to the early construction process of vibrating, pouring and surface treatment when the concrete begins to harden.

The final setting time of concrete is generally about 28 days, which refers to the time when the concrete is completely solidified and reaches the design strength.

Before this time, the strength of the concrete will continue to increase, so in the construction, Liang Qimin is required to control the pouring, maintenance and oak branch demoulding in time according to the requirements of the strength of the trapped concrete.

The initial setting time and final setting time of concrete refer to the time when the concrete begins to harden and completely set after adding water.

The initial setting time and final setting time are affected by a variety of factors, such as the concrete ratio of the concrete matching, the variety of Qiaoxiao cement, air temperature, humidity, wind speed, etc. In the construction, it is necessary to adjust and control according to the specific situation to ensure the quality and construction effect of concrete

Summary. Hello Extended Information: The initial setting time of concrete refers to the time when the concrete slurry begins to solidify and loses fluidity, that is, the time when the cement reaction in the concrete begins to cause curing.

Generally speaking, the initial setting time refers to the time when the bearing properties of the concrete slurry begin to decline. The initial setting time is one of the important time points in the construction process of concrete, because it marks that the concrete can begin to be processed in the future, such as sanding, plastering, etc. : The final setting time of concrete refers to the time when the cement reaction in the concrete slurry is completely completed and the concrete is completely hardened.

Before final setting, the concrete can be processed; After the final setting, the concrete has reached a certain strength and can no longer be processed.

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We'll be happy to answer for you. The initial setting time of concrete is 1-6 hours, and the final setting time is 3-24 hours.

Hello Extended Information: The initial setting time of concrete refers to the time when the concrete slurry begins to solidify and lose fluidity, that is, the time when the cement reaction in the concrete begins to cause curing. Generally speaking, the initial setting time refers to the time when the bearing properties of the concrete slurry begin to decline.

The initial setting time is one of the important time points in the construction process of concrete, because it marks that the concrete can begin to be processed in the future, such as sanding, plastering, etc. : The final setting time of concrete refers to the time when the cement reaction in the concrete slurry is completely completed and the concrete is completely hardened. Before the final setting, the coagulated megasock soil can be processed into the family leakage; After the final setting, the concrete has reached a certain strength and can no longer be processed.