Under what circumstances is concrete white?

Take a look at the test blocks that were made. If the standard test block is also like this, then it must be a problem of concrete proportion. It is possible that the mixing plant uses the wrong cement. If the strength of the standard culture test block is normal, then it is your maintenance problem.

According to your description, when the mixing plant produces concrete, the cement tank is blown wrong, and the misuse of ore-forming powder or fly ash is more likely.

There are a few questions that need to be further clarified:

1. What is the grade of concrete?

2. Is the initial setting normal?

3. Is it normal maintenance?

4. Concrete has no strength, does it mean crispy?

5. What is the surface situation?

For now, as far as I can infer it:

There are too many mineral admixtures, or even the wrong ones, or even no cement, and the wrong mineral admixtures, and the possibility of mineral powder is greater, because the mineral powder is white, and the fly ash is gray.

It should not be an admixture, and an overdose of an admixture is usually yellowing and peeling.

Lack of water, pulverized surface. The air is too dry in the curing stage, and there is no water for curing.

I don't know when your concrete is first set! If you look at it this way, it should be caused by a lot of water reducer exceeding the proportion of use or too much fly ash! If the superplasticizer is used too much, it will cause dilution, that is, the cement loses its strength, and the upper and lower layers of the concrete are sand!

The strength will be greatly reduced! It's not even concrete anymore.

Pro, the cyan color of white cement after solidification is due to the phenomenon of blue, green or blue-green after hardening of the cement slurry of Hu Socks, which mainly occurs in the use of slag cement or cement and mortar with a high content of mineral powder. This problem was studied in 1957 by the early grandson, and the discoloration was attributed to the sulfide contained in the slag, and the complex reaction with some elements or compounds of cement produced trace amounts of Fes and Mns, making the hydration products blue-green. However, after the concrete surface is exposed to the air for a period of time, these sulfides will oxidize, and the color will disappear, the more dense the pants are tight, the longer it will take for the color of the high-strength concrete to fade Oh If my answer is helpful to you, please also give a thumbs up (comment in the lower left corner), look forward to your like, your efforts are very important to me, and your support is also the driving force for my progress.

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Concrete whitting is a sanding phenomenon: X0D X0A concrete surface is rough, the finish is poor, the general color is whitish, not solid. Once walked or rolled by the vehicle, the surface is dusted first, and with the increase of the number of walking or rolling, the sand particles gradually loosen or fall off in pieces.

In the construction of many projects, no matter what part is poured, it is hoped that the concrete mixture is the best self-leveling, and blindly pursues the construction progress (the faster the better), and rarely cares about the quality and cost (the phenomenon of adding water on site is widespread), buries hidden dangers to the quality of the project, and causes a huge waste of cost and resources. It can be said that these bad behaviors have become a stumbling block to the progress of concrete technology and engineering quality in China, and have seriously affected the durability and service life of concrete structures. x0d x0a (2) The basic work of many units is not solid, and the "quality first" is not really implemented, and the quality management work is not in place, which is often a formality.

The hydration of cement is a long process, which continues to penetrate deep into the cement particles with the extension of time, and the strength increases with the deepening of hydration. However, the hydration of cement must be carried out normally in a humid environment, therefore, if the moisturizing curing is not timely or the time is not enough, the moisture of concrete in the dry environment will evaporate rapidly, and the hydration of cement will be affected, and even stop hydration when serious, cause the substantial reduction of surface strength, and poor wear resistance. However, moisturizing and curing should not be too early, watering when the concrete is more "tender" will lead to a large area of peeling, sand particles exposed, and sand after use.

x0d x0a (2) project subcontracting and subcontracting, no profit if you don't rush the construction period, and use more manual labor to affect the income of the "boss", so you don't pay attention to or take care of the maintenance after concrete pouring, and there is the idea that the quality is "almost".

Summary. Dear, <>

Hello, I am honored to answer for you, why ordinary concrete will precipitate white substances is: the salt substances in the concrete evaporate to the surface with the water in the concrete and crystallize to form white crystals, the solution is: concrete alkali return not only affects the appearance but also destroys the mechanical properties and durability, and effective methods must be taken to prevent and control.

According to the necessary conditions for alkali return, as long as any of these conditions are missing or one of them is destroyed, saline alkali will not be formed, and prevention and control can be achieved.

Why does ordinary concrete precipitate white substance? How to solve it?

Dear, <>

Hello, I am honored to answer for you, why the ordinary concrete will precipitate white substances is: the salt substances in the concrete evaporate to the surface with the water in the concrete and crystallize to form white crystals, the solution is: the concrete alkali return not only affects the appearance but also destroys the mechanical properties and durability, and must take effective mountain dust methods to prevent and control.

According to the necessary conditions for alkali return, as long as any of these conditions are lacking or one of them is destroyed by comma Zen, the salinity will not be formed, and the prevention and control can be achieved.

Pro, ordinary concrete refers to cement as the main cementitious Hongming material, with water, sand, stone, if necessary, mixed with chemical admixtures and mineral admixtures, according to the appropriate proportion, after uniform mixing, dense molding and curing hardening of artificial stone.

Why does ordinary concrete precipitate white substance? How to solve it?

Dear, Yanyin will be happy to answer for you. Why does ordinary concrete precipitate white substance? How to solve it?

A: The appearance of white powder in concrete can be treated with dilute acetic acid. A layer of white powder on the concrete is actually some small molecule salts, because the concrete contains a large number of calcium and magnesium ions, which can be combined with oxalic acid to form calcium oxalate, magnesium oxalate precipitation, but will increase the white powder.

Acetate is soluble in water and can be washed with dilute acetic acid, which is much better than oxalic acid.

What is the white substance that precipitates from the surface of concrete? Hello dear! The precipitation of white matter on the surface of concrete is the panalkaline phenomenon of Shuichangsun mud after being exposed to water.

1. The reason for the whitening of the concrete floor There are two reasons for the whitening of the concrete floor, one is that the salt substances in the concrete evaporate to the surface with the water in the concrete and crystallize to form white crystals; Second, when the concrete ground is cured, the curing agent is used too much, the concrete ground has reached saturation with the curing agent, and the remaining curing agent material remains on the surface of the concrete, evaporating to form white crystals. Second, the hazards of concrete ground whitening Concrete whitening will not only affect the appearance of the ground, but also form a transparent capillary between the top and bottom of the concrete, which will have some impact on impermeability, durability and service life. It is very likely that the concrete floor will be dusted and sanded in a very short period of time, which will affect the normal use of the ground.

3. The solution to the whitening of the concrete floor is that the salts in the concrete precipitate to the surface, and we can reduce the probability of whitening by screening and selecting the concrete materials, but it is difficult in practice. In fact, the use of curing agent can completely solve the whitening phenomenon, as long as we pay attention not to use excessive curing agent, do not let the curing agent crystallize on the surface of concrete. The concrete sealing curing agent can penetrate into the concrete, react with the free calcium in the concrete, and the resulting substances can seal the pores of the concrete floor, making it a dense whole, and then greatly improve the performance of the concrete floor.

If the pores of the concrete surface are blocked, the salts cannot be precipitated from the pores to the concrete surface, and the concrete will not be whitened.