Contents of this article
Antifreeze concrete antifreeze standard?
What standard is jc475-2004?
What are the regulations for the use of concrete antifreeze?
What standards require the addition of antifreeze to concrete? specific?
At what temperature can concrete be used with antifreeze?
Is it better to add antifreeze or salt to concrete in winter?
What is the national standard for antifreeze water reducing agent?
What are the standards for antifreeze concrete antifreeze?
1) Chloride salt antifreeze: Antifreeze that uses chloride salt (calcium chloride, sodium chloride) as the antifreeze component can be used in unreinforced concrete projects.
2) Chloride salt rust-inhibiting antifreeze: Antifreeze using chlorine salt and rust inhibitor (sodium nitrite, etc.) as antifreeze components can be used in reinforced concrete projects, but cannot be used in the following structures RC.
① Structures used in environments with a relative humidity greater than 80%, structures in areas where the water level rises and falls, open-air structures or structures that are often exposed to water.
② Structures in contact with galvanized steel or aluminum iron, as well as structures with exposed embedded iron parts without protective measures.
③ Structures in contact with corrosive media containing acid, alkali or sulfuric acid.
④ Structures that are often exposed to ambient temperatures above 60°C.
⑤Structures using cold-drawn steel bars or cold-drawn low-carbon steel wire reinforcements.
⑥Thin-walled structures of water supply and drainage structures, crane beams, roof trusses, drop hammer or forging hammer foundations and other structures for intermediate and heavy working cranes.
⑦Electrolysis workshop and structures within 100m from high-voltage DC power supply.
⑧ Structures close to high-voltage power sources, such as power stations and substations.
⑨Prestressed concrete structure.
What standard is jc475-2004?
JC 475-2004 is the national mandatory standard for concrete antifreeze. The specific number and name of this standard is: JC 475-2004 Concrete Antifreeze.
The main contents of this standard are as follows:
This standard specifies the terms and definitions, classification, technical requirements, test methods, inspection rules, product instructions, packaging, and storage of concrete antifreeze .
This standard is applicable to cement concrete antifreeze with specified temperatures of -5*C, -100C and -15℃. Antifreeze that has passed the temperature test according to this standard can be used at a temperature 5°C lower than the specified temperature.
What are the regulations for the use of concrete antifreeze?
The usage method is as follows: For construction at 0~ -5℃, 4~6% can be added. For construction at -5~ -10℃, 5~8% can be added at -10~ -15℃ Under construction conditions, 8~10% concrete antifreeze can be added. Early strength antifreeze uses special antifreeze materials, which can effectively reduce the freezing point of concrete and mortar and greatly improve the antifreeze performance of concrete and mortar at negative temperatures.
And it can increase the early strength of concrete and mortar by more than 80% without reducing the later strength, thereby ensuring that the strength is equally developed under positive and negative temperature conditions. The effect is remarkable.
What standards require the addition of antifreeze to concrete? specific?
"Concrete Admixtures" (GB 8076-2008) antifreeze can be divided into strong electrolyte inorganic salts (chlorine salts, chlorine salt rust inhibitors, chlorine-free salts), water-soluble Organic compounds, compounds of organic compounds and inorganic salts, and compound antifreeze. It is divided into two categories: freezing point lowering type and surfactant type. Those that lower the freezing point include low-carbon alcohols, glycols and amides. Surfactant types can form a hydrophobic absorption film on the surface of materials, such as acidic phosphate ester amine salts, alkyl amines, fatty acid amides, organic acid esters, alkyl succinimides, etc. For example, if it is mixed into concrete for winter construction, it can harden the concrete at negative temperatures and reach sufficient anti-freeze strength within the specified time. Can be made into powder or liquid. It is used to prevent frost swelling damage caused by concrete construction under negative temperatures in winter. Ensure normal construction of concrete under negative temperatures. Its main ingredients are sodium nitrite, carbonate, calcium chloride, calcium nitrite, urea, ethylene glycol, etc. They lower the freezing point in concrete mixes. It can also be combined with water-reducing agent, air-entraining agent, etc. to prevent freezing.
How many degrees below zero can the concrete plus antifreeze be used?
It is necessary to add antifreeze at minus 5 degrees Celsius.
Antifreeze concrete is a substance that hardens at negative temperatures, achieves expected performance under specified curing conditions, and prevents moisture in the material from freezing at low temperatures. Ensure the normal construction of concrete under negative temperature and reduce the freezing point in the concrete mixture.
It can be combined with water-reducing agent, air-entraining agent, etc. for anti-freezing effect. Used for various concrete projects and during construction in cold seasons. Allow the concrete to hydrate normally in a negative temperature environment of 0°C to -15°C; lower the freezing point and improve the early strength of the concrete.
According to the building materials industry standard JC 475-2004 (replacing JC/T475-1992) antifreeze is defined as: it can harden concrete at negative temperatures and achieve expected performance and sufficient antifreeze strength under specified curing conditions. of admixtures. It is a substance that can prevent moisture in materials from freezing at low temperatures.
Is it better to add antifreeze or salt to concrete in winter?
No
When adding water to cement concrete, salt cannot be added, that is, salt water or sea water cannot be used. Salt will destroy the microstructure of the concrete and affect its strength.
Antifreezing Agent, according to the Building Materials Industry Standard of the People's Republic of China JC
475-2004 (replacing JC/T475-1992), antifreeze is defined as: the ability to make concrete Hard at negative temperature��, and admixtures that achieve expected performance under specified curing conditions. It is capable of operating at low temperatures.
What is the national standard for antifreeze water reducing agent?
Water reducing agent standard GB8076 -2018 concrete admixture standard.
Water reducing agent is a concrete admixture that can reduce mixing water consumption while maintaining the slump of concrete basically unchanged. Most of them are anionic surfactants, including lignin sulfonate, naphthalene sulfonate formaldehyde polymer, etc. After being added to the concrete mixture, it has a dispersing effect on the cement particles, which can improve its workability, reduce the unit water consumption, and improve the fluidity of the concrete mixture; or reduce the unit cement consumption and save cement. </p
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