-
Ferroconcrete.
The service life is closely related to the material properties of the concrete, the structural design, and the influence of natural conditions. General civil construction.
It is 50 years old, and 80 years or more for large or important buildings.
Generally, reinforced concrete has a protective layer, of course, natural erosion and destruction, the relative steel bar must have different degrees of corrosion.
If there is later maintenance, those defects can be remedied, its service life will be greatly improved, the building will be regularly inspected, found hidden dangers must be dealt with a certain amount of technology, early detection and early treatment, so that the life of the building will be greatly improved.
Note: Reinforced concrete generally refers to a structure made of concrete reinforced with steel bars. A structure made of steel and concrete. The steel bar is subjected to tensile force, and the concrete is subjected to pressure.
Concrete is made of cementitious material.
Cement, sand.
Stone and water, and admixtures, admixtures, etc. are mixed in a certain proportion. After solidification, it is as hard as stone, and has good compression ability, but poor tensile ability, and is easy to break due to tension. In order to solve this contradiction and give full play to the compressive capacity of concrete, a certain number of steel bars are often added in the concrete tension area or the corresponding part, so that the two materials are bonded into a whole and bear external force together.
This type of concrete, which is equipped with reinforced steel, is called reinforced concrete.
-
For buildings with a safety level of Grade II, the general design service life is 50 years, and the strength of the concrete can meet the requirements of the design service life. The steel bars inside will not be subject to very severe rust due to the protective layer.
-
At present, the design life of ordinary high-rise residential structures is 50 years, while the property rights of residential buildings are 70 years.
However, the service life of the structure is 50 years, it is not good to say that it is not good for 50 years, if it is used and maintained properly, the weathering time of the cement will be delayed a lot, and the corrosion of the steel bars inside will also be slowed down, and the use of 70-100 years is not a problem.
-
1. Reinforced concrete is generally 50 years; The steel bars inside generally do not rust; Cement weathered in 100 years.
2. According to the requirements of the specification, the design reference period is 50 years, so all measures are taken according to the 50 years that can be used. For bridges, the state stipulates 100 years;
3. These measures are not calculated, but based on engineering experience and experiments. However, due to the complexity and uncertainty of the factors affecting the service life, the actual service life cannot be determined.
-
In those years, when I was doing the steel bar business, I heard this problem the most, because the steel bar may get wet during sales or transportation, so it is difficult to avoid a little rust on the surface. And people who buy steel bars will basically ask this question when they see the rust on the surface of steel bars, so I will talk about this problem with you here. The time will be very long and decades, this is the service life of the building, of course, bridges and other bridges have a hundred years of life, and the concrete that costs a lot of money is special, even the pouring is not the same.
To sum up, the tensile strength of concrete and steel bars is good, but the shear resistance is good, but it is not durable. If the concrete is not compacted due to vibration, concrete segregation and honeycomb surface during the pouring process, or the concrete protective layer is destroyed, the oxygen, acid gas and water molecules in the atmosphere will oxidize the steel bar through the void and then cause the steel bar to corrode.
<> many friends will use rusty steel bars when building houses, generally because of improper preservation, and the anti-rust measures are not in place if they are left for too long. In rural areas, steel bars are basically stacked at will, there is no pad cover, and it is easy for steel bars to corrode after a long time, but even so. If it doesn't rain in time, it's a disaster.
What sand is suitable according to the requirements of the product. When talking about the protective layer, the general construction site requires 50 mm. This is the degree of compactness, which is now required for concrete tamping.
The main thing is density. Insulates the air from humidity, causing secondary corrosion. Leaks, cracks.
and other external forces cause external leakage.
Whenever we see these exposed steel bars, we will find that we were fine when we tied them, but now they are rusty, a layer of yellow rust, and it looks very ugly. Even if the steel bar is as clean as new before it is buried in the concrete, considering that the electrochemical reaction on the surface of the steel bar inside the wet concrete cannot be avoided, the steel bar in the concrete will still have some rust, but the degree of rust is very light, and it has little effect on the adhesion between the two.
-
Personally, I think it is likely to continue to rust, and I personally think that the rust must be removed at this time, otherwise it is likely to cause the steel bar to oxidize all the time.
-
It does not rust continuously, because it is wrapped in concrete, and it does not come into contact with oxygen or moisture, so it does not rust.
-
It doesn't rust. This is because the steel bars mixed in the concrete are isolated from the air and do not oxidize, so it does not rust.
-
No. Because concrete contains less air, oxidation rarely occurs.
-
It will continue to rust, because there will still be a trace of oxygen in the reinforced concrete, and where there is oxygen, it will continue to rust.
-
It is still because the steel bar is already in a rusty state, and after coming into contact with the concrete, it will accelerate the speed of rust.
-
It will rust because it is determined by the external environment, and the rust will continue to rust, and the external environment will not be improved at all.
-
Summary. Hello, if there is water in the steel bar in the concrete, the steel bar will not rust, the steel bar rust not only needs water but also oxygen, there is no oxygen in the concrete, so the steel bar inside can not be embroidered.
Hope mine can help you.
If water enters the steel bars in the concrete, will the steel bars inside rust?
Hello, if there is water in the steel bar in the concrete, the steel bar will not rust, the steel bar rust not only needs Shui Xiang Bridge but also oxygen, Dong Zheng has no oxygen in the concrete, so the steel bar inside can not be embroidered. Hope mine can help you.
Hello, if there is water in the steel bar in the concrete, the steel bar will not rust, the steel bar rust not only needs Shui Xiang Bridge but also oxygen, Dong Zheng has no oxygen in the concrete, so the steel bar inside can not be embroidered. Hope mine can help you.
-
After the steel bar rusts, it will continue to rust when it is buried in the concrete, but the speed of rusting will slow down because the oxygen content in the concrete will be less.
-
The rusty steel bar will not continue to rust in the concrete, and oxidation will not occur.
-
If the quality of the concrete used in the construction process is not up to standard, after pouring, there are cracks, honeycombs, holes, hemp surfaces and other problems on the surface of the concrete, then, these concrete have defects, and the concrete with gaps cannot wrap the steel bar densely inside. After a long time, the steel bars that have been rusted are inside the concrete, and there is a possibility that they will continue to rust. Because first of all, there are cracks in the concrete, these cracks are connected with the outside air, and the air can directly contact the steel bars through these cracks, which provides conditions for the steel bars to continue to rust, in addition, if it rains heavily or stagnates water, the water will also enter the concrete through these cracks and contact with the steel bars, thereby corroding the steel bars.
-
Not recommended. Because the rust on the surface of the steel bar will continue to expand, if it is mixed into the concrete, it will cause gaps and air into the steel bar and the concrete because it cannot be completely wrapped, resulting in the rust of the steel bar after being damp in the air, so it is not recommended to use rusty steel bars to avoid potential safety hazards.
Severe treatment method of steel rust:1. Slightly corroded steel bar rust removal (steel bar rust Sanhong quietly within a month, especially 2 months):
Generally belongs to floating rust, the current more common rust removal method uses steel bar rust remover to remove rust, just gently transport a spray, you can look new. Whether it is the original steel bar that has not been processed, or the tied in-situ, threaded, disc round steel bar, etc.
2. Rust removal of severely corroded steel bars (refers to steel bar rust for more than three months):
1. Rust removal of disc round steel bars
For example, after the rust is removed, the base can be used quickly, so there is no need to remove the rust separately, mainly because the circle will remove the rust when it is straightened. However, if it is not used for a short period of time after derusting, it can be removed by simply soaking it with a rebar derusting agent.
2. Rust removal of unprocessed threaded steel bars
Wire brushes, sandblasting, shot blasting and rust removers can be used to remove rust.
3. Processed and centralized storage of steel bars for rust removal
You may wish to use sandblasting to remove rust, of course, the wire brush can also be used reluctantly.
-
If it is used for the construction of ordinary facilities and equipment, there is no problem, but if it is used for the use of large buildings, rusty steel bars will definitely not be used.
Questions. It's rusty.
Repairing the house can not.
It depends on the degree of rust, if it is serious, the house cannot be repaired.
Questions. The severity of the matter is not recognized.
If you wash the show, no.
If the rust on the steel bar is reached, and it can be easily scraped off by hand, this kind of thing is not recommended to repair the house. Of course, if you find a professional rust removal shop, you can also use it after rust removal. Brother scum.
Questions. That kind of rust removal is best.
Your actual situation is not serious, can you break off the rust with your hands? How high is the house?
Questions. The second house is not serious.
Is the second house two storeys tall?
It's easy to deal with if it's not serious.
-
Steel bar is one of the indispensable and important raw materials for building a house, I believe everyone has seen or heard of it in daily life, but in the process of being transported or used, it is easy to rust due to improper storage environment. So will the rusted steel bar continue to rust if it is used in concrete?
First of all, we need to understand the real cause of rust in the rebar, because the air is humid or the rebar accidentally comes into contact with water, the substances in the rebar will react with the oxygen in the air under the action of moisture.
And then the rust is formed!
Secondly, if the rusted steel bar is sealed in the concrete, under the premise of qualified pouring quality, for example, the poured concrete does not have inferior phenomena such as honeycomb and cracks, and it will not continue to rust under normal circumstances, because most of the qualified concrete pouring is isolated from the air, and the lack of rust conditions will inevitably reduce the occurrence of rust! However, if the concrete is sloppy or the quality is not up to par in the process of pouring construction, it is easy to cause cracks or honeycomb-like inferior phenomena, so it cannot completely isolate the oxygen in the air; Moreover, the concrete is not completely sealed, and if it is watered, the moisture can easily penetrate into the concrete, in which case the rusty steel bar may continue to rust! However, in the construction of regular houses, rusty steel bars are also avoided as much as possible, because after the steel bars are rusted, their strength will be greatly reduced, and if they are used in house construction, it will greatly affect the safety structure and quality of the house!
In addition, we usually need to maintain and protect the freshly poured concrete in time to avoid cracks, so as not to increase the risk of rusting steel bars in the concrete!
Therefore, it is necessary for the rusty steel bar to continue to rust in the concrete, which is based on certain chemical principles!
-
I don't think rusty steel bars will continue to rust in concrete; There is no clear basis for this, but I think that in concrete, the material is more abundant, it is more airtight, it will not enter the air, and it will reduce the erosion of the air, so it will not rust.
-
No. Because there is no air and moisture in the concrete, the rusted steel bars will not continue to rust in the concrete.
-
Yes. The condition for the rust of the steel bar is some water and nutrients, and there are these things in the concrete, so it can rust.
-
The rusty steel bar will continue to rust in the concrete, first of all, the moisture will penetrate in, the second is that the water that penetrates in contains oxygen, and the rust will act on the surface of some complete steel bars to accelerate the progress of rust. It is necessary to elaborate the specific scientific basis for analyzing the rust of steel bars that will continue to rust in concrete from the following three aspects.
First, moisture will penetrate in
First of all, the moisture will penetrate in, this is because the concrete may be damaged due to weathering for a long time, and the moisture will gradually penetrate when it rains, and the corresponding moisture will not evaporate without the sun in continuous rainy weather, so that it will gradually penetrate in, so that the progress of the rust will be accelerated under the contact between the acidic rain and the steel bar, because there will be some corresponding chemical reactions.
Second, the water that penetrates contains oxygen
The second is that the water that penetrates into contains oxygen, for the water that penetrates into the concrete, the full contact with the air in the process of forming rainwater will make the corresponding oxygen and rainwater combined, so that under the action of these acidic rainwater, it is also accompanied by the entry of this oxygen, which will accelerate the corrosion of the corresponding steel surface, and will produce a series of oxidation reactions.
This makes the rebar more susceptible to rust.
3. Rust will act on the surface of some intact steel bars to accelerate the progress of rust
The main reason is that the rust will have a series of chemical reactions with the corresponding steel bar, and the steel bar will gradually be corroded under the action of the corresponding rust, so that although the steel bar has been protected by the concrete to a certain extent, it will eventually be completely corroded over time.
Precautions to prevent rusting of steel bars inside concrete:
Only rusty steel bars should be used to bury in concrete, and at the same time, it is necessary to choose concrete with better materials, which is not conducive to the penetration of water, and can play a good protective effect.
The apparent density of concrete is the "mass per unit volume" of the concrete mixture after tamping, measured in kg m 3. The main points of the method are as follows: >>>More
This thing is actually not very clear, if you are a Chinese, you can say that it was invented in our country--- during the Qin Shi Huang period, the Chinese people used glutinous rice juice and sand soil to build the Great Wall, in fact, it is also a kind of concrete! >>>More
In real life, this reinforced concrete sleeper is still very useful, and the role is also very large, and some advantages and disadvantages of this reinforced concrete sleeper will be introduced below. In addition to saving a lot of high-quality steel, concrete sleepers also have the advantages of long service life, good track stability, and can meet the requirements of high speed and large volume. It has played a great role in promoting seamless lines. >>>More
It is 50 years old for general civil buildings and 80 years or more for large or important buildings. >>>More
The full name of the concrete wall is the concrete impermeable wall, the longitudinal cut of the vertical wall, and the wall is extended along the dam body. It is a wall-shaped anti-seepage building built by continuously making holes in a loose and permeable foundation, fixing the wall with mud, and pouring concrete into the holes. It is a hydraulic work on ZD sluice dams and so on. >>>More