Recommended reading: C20 concrete mix ratio and price
What are the concrete admixtures? Concrete admixtures are divided into four categories according to their main functions:
(1) Additives to improve the rheological properties of concrete mixture, including various water reducing agents, air entraining agents and pumping agents;
(2) Admixtures for adjusting the setting time and hardening performance of concrete, including retarders, early strength agents and setting accelerators;
(3) Admixtures to improve the durability of concrete, including air entraining agent, waterproof agent and rust inhibitor;
④ Admixtures to improve other properties of concrete, including air entraining agent, expansion agent, antifreeze, colorant, waterproof agent and pumping agent.
Ordinary water reducer: under the condition that the slump of concrete is basically the same, the water consumption for mixing can be reduced.
Early strength agent: accelerate the early strength development of concrete.
Retarder: prolong the setting time of concrete.
Air entraining agent: A large number of evenly distributed, stable and closed tiny bubbles can be introduced during concrete mixing.
Superplasticizer: Under the condition that the slump of concrete is basically unchanged, the mixing water consumption can be greatly reduced.
Early strength water reducer: it has both early strength and water reducing functions.
Retarding water reducer: it has retarding and water reducing effects.
Air-entraining water reducer: it has the functions of air-entraining and water-reducing.
Prevention: reduce the water permeability of concrete under hydrostatic pressure.
Rust inhibitor: Inhibit or reduce the corrosion of steel bars or other embedded metals in concrete.
Air entraining agent: In the process of concrete preparation, a large number of air holes are formed in concrete due to chemical reaction and gas release.
Expansion agent: make concrete expand in a certain volume.
Antifreeze: Harden concrete at negative temperature, and achieve sufficient antifreeze and strength within the specified time.
Colorant: Prepare concrete with stable color.
Accelerator: make concrete solidify and harden quickly.
Pumping agent: It can improve the pumping performance of concrete mixture.
In the prescribed dose, the side effects of additives are basically very small.
Concrete admixture manufacturer
First, the annual user recommended China excellent brand enterprise of concrete admixture.
Liaoning cologne fine chemical co., ltd.
Jiangsu bote new material co., ltd
Kezhijie new material group co., ltd
Hebei province concrete admixture factory
Beijing new century oriental building materials co., ltd.
Maanshan zhonghai new material co., ltd
Tianjin longfei concrete admixture co., ltd
The role of concrete admixture:
(? 1? ) can reduce the water consumption of concrete or increase the fluidity of concrete without increasing the water consumption.
(? 2? ) can adjust the setting time of concrete.
(? 3? ) reduce bleeding and segregation, improve workability and water elutriation resistance.
(? 4? ) can reduce slump loss and improve the pumpability of pumped concrete.
(? 5? ) can reduce shrinkage. Adding expansion agent can also compensate for shrinkage.
(? 6? ) delay the initial hydration heat of concrete, reduce the heating rate of mass concrete and reduce the occurrence of cracks.
(? 7? ) improve the early strength of concrete and prevent freezing at negative temperature.
(? 8? ) improve strength, increase frost resistance, impermeability, wear resistance and corrosion resistance.
(? 9? ) control the alkali-aggregate reaction, prevent the corrosion of steel bars and reduce the diffusion of chloride ions.
(? 10? ) is made of concrete with other special properties.
(1 1) Reduce the viscosity coefficient of concrete, etc.
Price list of concrete admixture:
pollute
In building construction, in order to speed up the solidification of concrete and prevent it from freezing in winter construction, additives such as high alkali concrete expansion agent, concrete antifreeze containing urea and ammonia water are added to concrete. This kind of additive, which contains a lot of ammonia, is reduced to ammonia in the wall with the change of temperature and other environmental factors, and is slowly released from the wall, resulting in a significant increase in the concentration of ammonia in the indoor air. Especially in summer, when the temperature is high, ammonia is released from the wall quickly, which leads to the indoor air ammonia concentration exceeding the standard seriously.
Ammonia is very soluble, so it is often adsorbed on the skin mucosa and conjunctiva, thus causing irritation and inflammation; Ammonia can paralyze respiratory cilia, damage mucosal epithelial tissue, make pathogenic microorganisms easy to invade and weaken human body's resistance to diseases; After ammonia is inhaled into the lungs, it can easily enter the blood through alveoli, combine with hemoglobin, and destroy the oxygen transmission function. After inhaling a large amount of ammonia in a short period of time, there will be symptoms such as tears, sore throat, hoarseness, cough, chest tightness and difficulty in exhaling. In severe cases, pulmonary edema and adult respiratory distress syndrome may occur, and respiratory irritation may occur.
Of course, while concrete admixtures bring convenience to people's construction, the use of some concrete admixtures will also pollute the indoor environment. Adding additives such as high-alkali concrete expansion agent and concrete antifreeze containing urea and ammonia water to concrete will greatly increase the concentration of ammonia in indoor air, thus becoming a major pollution source for decoration. This is also what the owner needs to pay special attention to when using concrete admixture.