Concrete retarder is one of the common used concrete retarding admixtures. Using it can extend the setting time of concrete. It can keep the plastic ability of fresh concrete for a long time, so as to improve construction efficiency. In the summer concrete construction and mass concrete construction, the addition of retarder in concrete can slow the release of cement hydration heat and reduce the high-temperature crack caused by hydration heat. A concrete retarder is an indispensable additive for continuous casting, pumping, mass concrete construction, and other construction processes. Retarding admixtures’ application is quite extensive. They are commonly used in prestressed concrete, dam concrete, slip form construction concrete, and fluidized concrete. It is also suitable for large slump concrete because of its excellent slump retention.
Main Types of Concrete Retarders
The main types of concrete retarders are as follows 1. Hydroxycarboxylic acids and their salts, such as tartaric acid, citric acid, gluconic acid, and its salts, and salicylic acid. 2. Sugary carbohydrates such as molasses, glucose, sucrose, etc. 3. Inorganic salts such as borate, phosphate, zinc salts, etc. 4. Lignosulfonates such as calcium lignosulfonate, sodium lignosulfonate, etc. Kingsun sodium gluconate is the most commonly used concrete retarder.
Kingsun sodium gluconate can significantly delay the onset time and end time of solidification of concrete. Adding sodium gluconate can extend the working time of concrete. The working time of concrete extends from a few hours to a few days without compromising the strength of concrete. This is an important advantage especially on hot days and when it needs to be placed for a long time. Here are some other advantages of sodium gluconate as a concrete set retarder.
1. Adding sodium gluconate can reduce the water to cement ratio, which can increase the strength of the concrete and form a high-quality concrete.
2. Large and heavyweight perfusion engineering are difficult to construct. Due to the addition of sodium gluconate, the improvement of the workability of the concrete and the delay of the solidification time can avoid the formation of joints on the structure, and as a result, the structural strength can be improved.
3. The use of sodium gluconate allows concrete to maintain a water-cement ratio in hot areas and enhances concrete performance. For example, a large amount of sodium gluconate was used in the construction of bridges in the Middle East.
4. In the modern concrete industry, premixed concrete is formulated in a central place and then transported through a mixer truck. In this case, it is important to increase the workability of concrete and delay the initial set time.
Purpose of Using Concrete Retarder
1. Concrete retarder chemicals can delay the setting time of cement slurry on a commercial concrete surface for more than 12-24 hours.
2. The use of concrete retarding agents does not reduce the strength of commercial concrete and the strength of steel reinforcement.
3. Commercial concrete treated with concrete retarders can obtain a 3~5mm uniform aggregate exposed surface after molded.
4. No corrosive effect on steel formwork and steel bars using retarder for concrete.
5. Concrete setting retarders can increase the decorative effect, reduce labor intensity and save construction costs.
Precautions for Retarders Used in Concrete
When changing the cement or adding the new cement, the compatibility test of concrete retarder and cement should be done.
For the requirements of the admixture retarder, the concrete should be tested beforehand to check the setting time.
Properly mix concrete retarder and cement according to the test mix ratio. When pouring concrete, strictly operate according to the construction specifications.
When concrete retarders combinate with other concrete admixtures, their compatibility should be tested first.
In the winter construction period, in order to improve the early strength of concrete, the usage of cement in concrete should be properly adjusted.
Buy Concrete Set Retarder in KINGSUN Factory
Henan Kingsun Chemical Co., Ltd. is a factory specializing in construction chemical concrete additives. It is one of the leading concrete set retarder suppliers and producers in China. Over the years, Kingsun has been adhering to the business philosophy of providing consumers with affordable quality products and it is committed to producing and developing more quality products to provide consumers with the better consumer experience. Kingsun has a number of product certificates, such as ISO9001 quality management system, ISO14001 environmental management system, OHSAS18000 occupational health, and safety management system.
In addition to retarders, our company also has various other types of concrete additives, such as sodium naphthalene sulfonate formaldehyde and polycarboxylic acid superplasticizers and other chemical admixtures for construction. Products from our company have exported to many countries and they get highly praise by consumers. We have long-term friendly cooperation with many companies. If you would like to know the concrete retarder price or some other information about our products, please send us an e-mail or leave a message, we will reply to you as soon as possible.