How to deal with the large carbonization depth of the surface layer of the new concrete structure

The strength is enough to deal with it, the reason for the thickness of the carbonization layer is that your concrete curing is not very good, if it is a rebound detection and therefore low strength, you can grind the carbonization layer off with a grinder, which will be more troublesome, and then carry out rebound detection, the general strength can go up. If you can't drill the core, determine the strength. If the carbonization depth is high and the strength meets the design requirements, there is no need to do any treatment.

The first floor is not right, the carbonization layer is greater than 3mm 3 months after the new concrete is formed, and it is greater than 6mm in 10 months'I've seen it all, and the carbonization of the concrete surface layer in 50 years is less than two millimeters from the book, and the actual structural concrete is impossible to achieve, unless you keep watering and curing it for more than 14 days every day.

It's all formed, what else do you want to do with it? The so-called carbonization depth is an indirect reflection of the cement content of your concrete.

If the carbonization depth is too deep, it can only be said that the construction process is not divided when you pour the concrete, or there is a problem with the concrete itself.

Again, find the best concrete manufacturer to understand, or give more gifts to the people at the quality supervision station.

This is simply impossible, it is the people at the quality supervision station who are embarrassing you! The gift was not enough, and the carbonization of the concrete surface layer in 50 years was less than two millimeters.

What is the effect of the high carbonization depth of concrete on the quality of concrete? Hello dear, it has little impact on the strength for a short time, but because of neutralization, it will have a great impact on the steel bar, and it is easy to rust! 1. If the carbonization depth of the concrete is too large, it will accelerate the corrosion of the steel bars in the concrete.

Originally, the design was originally reinforced concrete, and the steel bars were used to bear the tensile stress of the structure, but now the steel bars are corroded, which will cause accelerated structural failure. To slow down the carbonization of concrete, for example, the use of low-permeability concrete, or the use of coatings on the surface of the concrete to isolate carbon dioxide. 2. The main mineral components of cured concrete are tricalcium silicate and dicalcium silicate, which are exposed to the air containing moisture carbon dioxide to generate calcium carbonate, and the strength of calcium carbonate is much lower than that of calcium silicate, and this concrete component is called being weathered.

People use the different pH of calcium carbonate and calcium silicate to measure the degree of weathering with an acid-base indicator called phenolphthalein blue solution, which is called 'carbonization depth'. The deeper the carbonization depth, the more severe the weathering. 3. With the extension of the age of concrete, the greater the carbonization depth value, the smaller the conversion coefficient of the rebound data.

The carbonization depth is not the same as the design strength of the concrete, if the carbonization depth of the concrete does not reach the thickness of the steel reinforcement protective layer. 4. Carbonization and neutralization of concrete, so that the calcium hydroxide in the concrete reacts with the carbon dioxide in the air to produce water, and when the depth exceeds the protective layer, the steel bar will rust. Hope it helps.

Your statement is incorrect, the depth of carbonization is mainly related to whether the concrete is compact, whether the environment is wet, and the size of carbon dioxide concentration. In general, high-strength concrete is denser and should be more difficult to carbonize. Concrete itself is alkaline and reacts with moisture and carbon dioxide in the air over time.

The partial alkalinity of the reaction disappears, which is called the carbonization layer, and its depth is the carbonization depth. The speed of carbonization is related to the quality of the concrete itself, air quality, climate and other factors. For general concrete components, the concrete is high, and the carbonization rate is generally slower than that of poor quality concrete in the same environment, that is, the carbonization depth will be small rather than large.

Some people will think that the depth of carbonization affects the strength of concrete, but in fact, this is wrong, generally speaking, the strength of concrete affects the speed of carbonization, which affects the depth of carbonization.

Extension: The strength grade of concrete refers to the compressive strength of concrete. According to the standard of "Concrete Strength Inspection and Evaluation Standard" (GB T50107-2010), the strength grade of concrete should be determined according to the standard value of its cubic compressive strength.

The symbol c is used with the standard value of the compressive strength of the cube (in n mm 2; or MPA meter).

The compressive strength of concrete is obtained through the test, and the cube specimen with a side length of 150mm is used as the standard size specimen of concrete compressive strength below the latest standard C60 strength. In accordance with the "Standard for Test Methods for Mechanical Properties of Ordinary Concrete" GB T50081-2002, the cube with a side length of 150mm is cured to 28 days old under the conditions of standard curing (temperature 20 2, relative humidity of 95% to the beam), and the ultimate compressive strength measured by the standard test method is called the compressive strength of the concrete standard cube, which is represented by the FCU of the return to the stove. According to GB50010-2010 "Code for Design of Concrete Structures", in the overall distribution of the ultimate compressive strength of the cube, the compressive strength of the cube specimen with 95% strength guarantee rate is called the standard value of the compressive strength of the concrete cube (calculated as MPA), which is expressed by FCU.

The compressive strength with a 95% guarantee rate measured according to the standard experimental method is used as the concrete strength grade.

Carbonization of concrete is a chemical corrosion to which concrete is subjected to caution.

The process of CO2 gas in the air penetrating into the concrete, and the chemical reaction with its alkaline substances is trapped to form carbonate and water, and the process of reducing the strength of the concrete is called Xiaosen concrete carbonization, also known as neutralization, and its chemical reaction is: Ca(OH)2+CO2=CaCO3+H2O.

The cement generates a large amount of calcium hydroxide in the hydration process, so that the concrete void is filled with saturated calcium hydroxide solution, and its alkaline medium has a good protective effect on the steel bar, so that the surface of the steel bar generates insoluble Fe2O3 and Fe3O4, which is called passivation film (alkaline oxide film).

Summary. Hello. Reducing the water-cement ratio, optimizing the mix design, strengthening the curing and increasing the thickness of the protective layer can improve the carbonization resistance of commercial concrete.

Hello. Reducing the water-cement ratio, optimizing the mix design, strengthening the curing and increasing the thickness of the protective layer can improve the carbonization resistance of commercial concrete.

How to deal with the concrete carbonization depth value of 22mm after the concrete is burned.

Hello, 1. In the construction of wheel pins, the appropriate cement varieties should be selected according to the geographical location and surrounding environment of the building; 2. For the water level change area and the parts of the alternating effect of dry and wet or the cold area, the sulfate-resistant ordinary cement is selected; 3. High-strength cement should be selected for the scouring part;

The factors affecting the carbonization of concrete include environmental factors, raw material factors, construction operation factors, etc., and the factors affecting the carbonization of concrete are as follows

1. Cement varieties: cement varieties are the main factors affecting the carbonization of concrete, the admixtures in slag cement and fly ash cement contain activated silicon oxide and activated alumina, which combine with calcium hydroxide to form gelling active substances, reduce alkalinity, thus accelerating the process of forming calcium carbonate on the surface of concrete, and the carbonization rate is fast, and the carbonization speed of ordinary cement is slow;

2. The water-cement ratio is round, and the concrete bridge cavity wheel with a small water-cement ratio is slow due to the dense structure of the cement slurry, the air permeability is small, and the carbonization rate is slow;

3. Admixtures, there are many types of concrete admixtures, but admixtures containing chloride should not be used, because chloride will aggravate the corrosion of steel bars;

4. Pouring and curing quality, when pouring concrete, the vibration is not compact, the curing method is improper, and the curing time is insufficient, which will cause the capillary pores inside the concrete to be coarse, so that water sensitivity, air, and aggressive chemicals will enter the concrete, and accelerate the carbonization of concrete and the corrosion of steel bars.

Summary. Concrete carbonization refers to the reaction of carbon dioxide, sulfate and other substances in gas or liquid with water and calcium hydroxide in concrete to form carbonate, sulfate, etc., resulting in the weakening of calcification reaction in concrete, thereby affecting the strength and durability of concrete. The rate of concrete carbonization is related to factors such as environmental humidity, temperature, carbon dioxide concentration, etc.

Generally speaking, the carbonization depth of concrete is about about every year, but the actual carbonization rate is affected by a variety of factors, such as concrete strength, cement variety, season, etc. If the environment contains a large amount of harmful substances such as carbon dioxide and sulfates, the rate of carbonization of concrete may be accelerated. Therefore, in the process of design, construction and maintenance of concrete structures, it is necessary to comprehensively consider environmental factors, take appropriate protection and maintenance measures, delay the process of concrete carbonization, and improve the service life and safety of concrete structures.

Good. Concrete carbonization refers to the reaction of carbon dioxide, sulfate and other substances in gas or liquid with water and calcium hydroxide in concrete to form carbonate reed, thiosurarate, etc., resulting in the weakening of calcification reaction in concrete, thereby affecting the strength and durability of concrete. The rate of concrete carbonization is related to factors such as environmental humidity, temperature, carbon dioxide concentration, etc.

Generally speaking, the carbonization depth of concrete is about about every year, but the actual carbonization rate is affected by a variety of factors, such as concrete strength, cement variety, season, etc. If the environment contains a large amount of harmful substances such as carbon dioxide and sulfates, the rate of carbonization of concrete may be accelerated. Therefore, in the process of design, construction and maintenance of concrete structures, it is necessary to comprehensively consider environmental factors, take appropriate protection and maintenance measures, delay the process of concrete carbonization, and improve the service life and safety of concrete structures.

Hello, I am very happy to be able to answer this question for you, the concrete carbonization is because. Concrete is subject to chemical corrosion. When CO2 gas in the air penetrates into the concrete, it reacts with its alkaline substance to form carbonate and water, and the process of reducing the alkalinity of the concrete is called concrete carbonization.

I hope mine can help you.

The carbonization depth of concrete is large, and the countermeasures are as follows:

1. In the construction, the appropriate cement variety should be selected according to the geographical location and surrounding environment of the building;

2. For the water level change area and the parts of the alternating effect of dry and wet or the more severe cold areas, choose sulfate-resistant ordinary cement;

3. High-strength cement should be selected for the scouring part;

4. Analyze the properties of aggregates, such as the effect of acid-resistant aggregates with water and cement on the carbonization of concrete to a certain extent; Third, it is necessary to select a good mix ratio, appropriate amount of admixtures, high-quality raw materials, scientific mixing and transportation, timely maintenance and other strict technological means to reduce the amount of seepage and the erosion of other harmful substances to ensure the compactness of concrete;

5. If the building is located in an area with a bad environment, it is advisable to adopt an epoxy base liquid coating to protect the effect, and set a protective layer around the underground part of the building; Concrete is impregnated with various solvents, such as smeared with melted asphalt.

6. If the building once the concrete carbonization occurs, it is best to use epoxy material to repair, if the carbonization depth is larger, the loose part of the concrete can be chiseled, the harmful substances that enter can be washed, the concrete joint surface is chiseled, filled with epoxy mortar or fine stone concrete, and finally the epoxy base liquid is used for coating base protection.

Governance Measures:

First, in the construction, the appropriate cement varieties should be selected according to the geographical location and surrounding environment of the building; For the water level change area and the parts of the alternating dry and wet action or the more severe cold areas, sulfate-resistant ordinary cement is selected; High-strength cement should be selected for the scouring part;

Second, the properties of aggregates are analyzed, such as the effect of acid-resistant aggregates with water and cement on the carbonization of concrete to a certain extent;

Third, it is necessary to select a good mix ratio, appropriate amount of admixtures, high-quality raw materials, scientific mixing and transportation, timely maintenance and other strict technological means to reduce the amount of seepage and the erosion of other harmful substances to ensure the compactness of concrete;

The application of performance concrete in the project has reached an unprecedented scale, and some raw materials in the concrete have problems in the first place, and the quality fluctuates greatly, and even unqualified. In the design of the mix ratio, the raw materials are overly idealized, and the fluctuation of material quality in the construction process is ignored, resulting in the excessive difference between the construction mix ratio and the theoretical mix ratio.

A series of existing problems, such as the inherent wrong operation concepts and methods of some concrete on-site construction personnel, as well as the lack of concrete knowledge and weak quality awareness of management personnel, have greatly affected the quality of high-performance concrete. For the rebound strength measurement of concrete components, the carbonization depth of concrete will reach 3 4mm;

According to the "Technical Specification for Testing the Compressive Strength of Concrete by Rebound Method" (JGJT23-2011) in the measurement area of the concrete strength conversion table, the strength is reduced by nearly 10MPa, which is difficult to meet the design concrete strength requirements, and the continuous carbonization of the concrete may lead to the corrosion of the steel bar, and the reinforced concrete components are scrapped prematurely due to insufficient tensile strength.

Answer: Maintenance is not in place. The surface strength of concrete is low and the density is not enough. The amount of admixtures such as fly ash and mineral powder is excessive. The amount of cement is small, the Ca(OH) is less, and the carbonization is very fast and penetrates into the interior.

Poor construction quality, unreasonable vibration, etc., resulting in poor concrete compactness, other reasons such as cement quality, environment and so on.

The cement generates a large amount of calcium hydroxide in the hydration process, so that the concrete void is filled with saturated calcium hydroxide solution, and its alkaline medium has a good protective effect on the steel bar.

If the building once the concrete carbonization occurs, it is best to use epoxy material to repair, if the carbonization depth is larger, the loose part of the concrete can be chiseled, the harmful substances that enter can be washed, the concrete joint surface is chiseled, filled with epoxy mortar or fine stone concrete, and finally the epoxy base liquid is used as the coating base protection.