How long does it take for the cement pavement to be lighted? 20

The full hardening of cement, that is, curing and forming period, is generally 28 days in principle.

1. Cement is divided into the following according to its use and performance

1. General cement: cement commonly used in general civil engineering and construction projects. General cement mainly refers to:

The six categories of cement specified in GB175-2007 are Portland cement, ordinary Portland cement, slag Portland cement, porosyl Portland cement, fly ash Portland cement and composite Portland cement.

2. Special cement: cement for special purposes. Such as: G-grade oil well cement, road Portland cement.

3. Characteristic cement: a certain cement with outstanding performance. Such as: fast-hardening Portland cement, low-heat slag Portland cement, expanded sulfoaluminate cement, phosphoaluminate cement and phosphate cement.

2. Cement foaming can be divided into physical foaming and chemical foaming according to different production methods

1. Cement physical foaming.

The foaming agent is prepared into foam through mechanical equipment, and then the foam is added to the slurry made of cement-based cementitious materials, aggregates, admixtures, admixtures and water, and the insulation board (hereinafter referred to as the foamed cement insulation board) is mixed and stirred, poured and cured.

2. Chemical foaming of cement.

The foaming agent is added to the slurry made of cement-based cementitious materials, aggregates, admixtures, admixtures and water, and the insulation board is cured and cut by mixing, stirring and pouring to produce closed pores inside the slurry through chemical reaction in the mold.

This is based on the weather, if the weather is good, it will take about half a day, and if the weather is bad, you will have to wait. Six or seven hours.

Basically, it takes about 45 minutes for the concrete pavement to close!

It also depends on whether it is a commercial mixture, or a self-agitator!

From the completion of construction, it can be collected in 2-3 days.

Three hours of machine pressure is sufficient, and the labor time is longer.

Depending on the season and construction, the time will vary, and the clients I know generally follow one standard: walk without leaving a footprint.

Then, if you want to collect light over a large area, you will use a ride-on trowel.

This equipment works too fast, hundreds of square meters per hour, so it can ensure that the smoothing and polishing of the road surface can be completed in the best time period.

All kinds of small construction machinery for concrete, three-person machinery.

The times are advancing, reflecting the power of China's intelligent manufacturing, and saving labor is the real benefit.

This is not fixed, and it should be decided according to the situation after the concrete is completed.

If the temperature is high, the interval is short.

If the temperature is low, the interval is longer.

Generally, the initial vibration can be good, and after the surface water marks are not very obvious, it is the beginning to wipe the surface and collect the light, and the anti-skid groove will not bring up the cement slurry when the anti-skid structure is constructed.

Cement calendering is a special engineering project, which is a phenomenon formed after the cement floor is smoothed for 6-8 hours, evenly sprinkled on the construction surface with plain ash, and rolled out with a trowel.

1.The calendering of the cement floor should not be less than three times, and the proportion of water and cement should be strictly controlled;

2.The first time should be carried out immediately after the surface layer is laid, and it should be rubbed with a wooden trowel to wipe it flat and dense.

3.The second pass should be carried out after the initial setting of the cement.

4.The third calendering should be completed before the final setting, mainly to eliminate the smearing marks and occlude the capillaries, and avoid calendering after the final setting of the cement.

5.The standard bleaching curing process should be carried out between 24 hours after the calendering and final setting of the cement floor.

6.The construction of the cement floor surface layer should be arranged as far as possible after the completion of the plastering project on the wall and the roof of the shed, so as to avoid pollution and damage to the surface layer, and it is strictly forbidden to mix mortar on the cement floor.

Bricklayers use trowels for leveling and sensitizing.

Sprinkle a layer of cement and smooth it with a trowel.

Normally, the cement floor laid at 18 o'clock in the afternoon should be cleaned up before 23 o'clock in the evening, which is generally decided according to the speed of dehydration of the cement floor, and it is best to complete it within 4 hours, because more than 4 hours has exceeded the initial setting period of cement, and the time is too long to collect the light, which will affect the strength.

1. After the completion of concrete pavement paving or the completion of soft anti-skid structure, health maintenance will begin immediately. All kinds of concrete pavement, bridge deck and lap plate paved by mechanical paving should be sprayed with health care agent and moisturized and covered for health. In rainy days or in the case of sufficient water for health preservation, it is also possible to use sprinkling wet health care methods such as covering moisturizing film, geofelt, geotextile, sack, straw bag, straw curtain, etc., and it is not appropriate to use water preservation methods.

Second, the health time is determined according to the growth of concrete flexural tensile strength, should not be less than 80 of the design tensile strength, and special attention should be paid to the first 7 days of moisturizing (warm) health. Generally, the number of days of health preservation should be 14 21d, the high temperature day should not be less than 14d, and the low temperature day should not be planed, and it should be 21d. For concrete pavement mixed with fly ash, the shortest health time should not be less than 28d, and the low temperature days should be appropriately extended.

3. In the early stage of concrete slab health, it is strictly forbidden for people, animals and vehicles to pass, and after reaching the design strength of 40, it can be passed. During the pavement health period, temporary temporary bridges should be built at level crossings. After the panel reaches the design tensile strength, it is released to traffic.

According to the final setting time of cement, it generally takes 28 days.

Not less than 7 days and nights, according to the following.

Concrete curing method:

Natural curing: sprinkling water curing and spraying plastic film curing. The former covers the concrete with straw curtains, etc., and often sprinkles water to keep it moist. The curing time depends on the cement type, such as ordinary Portland cement concrete, not less than 7 days and nights.

The latter is suitable for high-rise structures and large-area concrete structures that are not easy to be cured by sprinkling, etc., and the perchloroethylene resin plastic solution is sprayed on the surface of the concrete with a spray gun, and a thin film is formed on the surface of the concrete after the solution volatilizes, isolating the concrete from the air, preventing the evaporation of water in the concrete, ensuring the normal progress of cement hydration, and the film can age and fall off by itself after the curing is completed. Prevent the evaporation of water in the concrete to ensure the normal hydration of the cement, and the film can age and fall off by itself after the curing is completed.

The importance of concrete pavement:

First, the purpose of concrete curing.

1. After pouring concrete, if the climate is hot and dry air, and there is no timely maintenance, the water of concrete curing concrete will evaporate too quickly, and the formation of dehydration can make cement particles form gels without complete hydration, unstable crystallization, and lack of sufficient bonds, which will appear on the surface of the concrete in flakes or powders falling off.

2. When the concrete does not have enough strength, the premature evaporation of water will also produce large shrinkage deformation and dry shrinkage cracks. Therefore, the maintenance in the early stages after concrete pouring is very important. Concrete should be cured immediately after final setting, and dry and hard concrete should be cured immediately after pouring.

2. Mechanism and importance.

1. When the concrete is poured, it is vibrating and compacted, and it will be condensed after a period of time, and its hardening is achieved through the hydration of the cement in the concrete setting process. Cement hydration is directly related to the temperature and humidity of concrete curing. Especially in the early stage of concrete curing, if it is not regularly sprinkled with water to keep its surface moist or the curing time is too short, the concrete surface will cause cracks to dry up and shrink due to premature evaporation of water or form capillary net breathable water leakage.

The impermeability of concrete is reduced.

2. Under normal circumstances, the water requirement for cement to complete hydration in the hardening process of concrete is about 25 of the amount of cement, and the remaining water is used to meet the requirements of concrete construction and concrete workability. However, in engineering practice, if the concrete does not take corresponding maintenance measures to create a humid environment for the concrete, the water in the natural environment of the concrete will evaporate too quickly, and the moisture loss of the concrete will be too fast, which is difficult to meet the hydration response needs of the cement.

It depends on the grade of concrete you pour and the weight of the car.

Take the common C25 concrete pavement on the construction site as an example, 3 days for a small car and 7 days for a large car!

concrete: Abbreviated as "concrete (tóng)": refers to the general term of engineering composite materials that cement aggregates into a whole by cementitious materials.

The word concrete usually refers to the use of cement as cementitious material, sand and stone as aggregate; 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.

Raw materials: Cement, lime, gypsum and other inorganic cementitious materials are mixed with water to make the concrete mixture plastic; In addition, the strength is generated by the condensation hardening of various types of concrete by chemical and physical chemistry. Generally speaking, drinking water can meet the requirements of water for concrete mixing.

Excess acids, alkalis, salts, and organic matter in water can all have harmful effects on concrete. Aggregate not only has a filling effect, but also has an important impact on the bulk density, strength and deformation properties of concrete. To improve some properties of concrete, admixtures can be added.

Due to the obvious technical and economic effects of admixtures, it has increasingly become an indispensable component of concrete. In order to improve the workability of the concrete mixture or the performance of the hardened concrete, save the cement, the finely ground mineral material admixture can also be incorporated when the concrete is mixed. It is divided into two categories: active and inactive.

The nature and quantity of admixture affect the strength, deformation, heat of hydration, impermeability and color of concrete.

Cement concrete pavement refers to the pavement with cement concrete as the main material as the surface layer, referred to as concrete pavement. Also known as rigid pavement, commonly known as white pavement, it is a high-grade pavement. Cement concrete pavement has plain concrete, reinforced concrete, continuous reinforced concrete, prestressed concrete and other pavements.

Is there anything else I can do to help you?

When the average temperature is above 20, 3D on the trolley, 14D on the car, 28D on the all-round.