Dongke Group Logo
concrete admixtures
What is the concrete admixtures?
2020-09-18
Concrete Retarder
2020-09-24

Superplasticizer in concrete

According to the difference of the main chain structure, the polycarboxylic acid superplasticizer products can be divided into two categories: one is based on acrylic acid or methacrylic acid as the main chain and grafted with polyethers of different side chain lengths. The other type is polyethers with maleic anhydride as the main link and different side chain lengths. Based on this, a series of high-performance water reducer products with different characteristics have been derived.

Before the emergence of polycarboxylic acid admixtures, there were lignosulfonate admixtures, naphthalene sulfonate formaldehyde condensate, melamine formaldehyde condensate, acetone sulfonate formaldehyde condensate, sulfamate formaldehyde condensate, etc. In the early 1980s, Japan took the lead in successfully developing polycarboxylic acid water reducers. The new generation of polycarboxylic acid superplasticizer overcomes some of the disadvantages of traditional superplasticizers. It has the advantages of low dosage, good slump retention performance, low concrete shrinkage, strong adjustability in molecular structure, and great potential for high performance. Outstanding advantages such as not using formaldehyde in the process.

In many concrete projects, traditional high-efficiency concretes such as naphthalene series are increasingly unable to meet the needs of the project due to the limitations of technical performance. A new generation of water-reducing agent that has attracted much attention at home and abroad, polycarboxylic acid-based high-performance water-reducing agent, because it has truly designed an effective molecular structure based on the action mechanism of dispersed cement, it has a super-dispersed type and can prevent concrete slump loss Without causing obvious retardation, it can play a higher plasticizing effect at low content, good fluidity retention, large degree of freedom in adapting the cement to a wide range of molecular structures, multiple synthesis techniques, and large room for high performance, which can enhance concrete The effect is remarkable, it can reduce the shrinkage of concrete, the content of harmful substances is very low and other technical performance characteristics, which endow the concrete with excellent construction and w orkability, good strength development, excellent durability, and the polycarboxylic acid-based high-performance water reducing agent has good Comprehensive technical performance advantages and environmental protection characteristics meet the needs of modern concrete engineering. Therefore, polycarboxylic acid-based high-performance water-reducing agents are gradually becoming the preferred admixture for the preparation of high-performance concrete. According to reports, the use of polycarboxylic acid admixtures in Japan has accounted for more than 80% of all high-performance admixture products, and North America and Europe have also accounted for more than 50%.

1. The dosage of polycarboxylic acid superplasticizer is 0.4% to 2.5% of the total weight of the gelling material, and the usual dosage is 0.8% to 1.5%. Before use, a trial mix test of concrete should be carried out to find the best content.

2. Polycarboxylic acid superplasticizer can not be mixed with naphthalene superplasticizer. When using polycarboxylic acid superplasticizer, the mixer and mixer truck that have used the naphthalene superplasticizer must be rinsed or it may be lost. Water reducing effect.

3. When using the polycarboxylic acid superplasticizer, it can be directly mixed in the form of the original solution, or it can be formulated into a certain concentration solution for use, and the amount of water brought by the HK-1 polycarboxylic acid superplasticizer itself is deducted.

4. Since the water reduction rate of concrete mixed with polycarboxylic acid superplasticizer is relatively large, the slump is highly sensitive to the water consumption, and the water consumption must be strictly controlled during use.

5. Polycarboxylic acid superplasticizer has good adaptability to most cements, but for individual cements, the water reduction rate may be low and the slump loss may be large. In addition, the fineness and storage time of cement may also affect the use effect of polycarboxylic acid superplasticizer. At this time, it is recommended to appropriately increase the dosage or compound other retarding components to solve the problem. Or please contact us, we will solve it for you in time.

6. After mixing with polycarboxylic acid superplasticizer, the air content of concrete increases (generally 2% to 5%), which is beneficial to improve the workability and durability of concrete. If it needs to be used in steam-cured concrete, For other special requirements, please contact us and we will solve them in time for you.

7. Due to the small content of polycarboxylic acid superplasticizer and high water reduction rate, the use of polycarboxylic acid superplasticizer to prepare various high-performance concretes above C45 can greatly reduce project costs and have significant technical and economic benefits. ; For the preparation of C45 and below grade concrete, although the cost of HK-1 polycarboxylate superplasticizer is relatively high, it can reduce the overall cost of concrete by increasing the amount of mineral admixtures, which also has certain technical and economic benefits.

The polycarboxylic acid super high-efficiency plasticizer itself has very good performance, the fusion performance of its cementing materials is more remarkable, the overall water reduction efficiency is higher, and the enhancement effect shown is very significant. It can effectively control the total amount of cement used, save more production input costs for enterprises, and enhance the durability of concrete itself. After inspecting the performance of the concrete mixture and on-site observation, it was found that the polycarboxylic acid super-efficient plasticizer has a better dispersion effect and plasticity retention than the naphthalene series. The construction site is easy to construct, and it solves the concrete protection that traditional admixtures are difficult to solve. The problem of poor slump improves the company’s economic benefits .

Chat with us
Chat with us
Questions, doubts, issues? We're here to help you!
Connecting...
None of our operators are available at the moment. You can leave a message directly to us, we will reply to you within 24 hours after receiving!
Our operators are busy. Please try again later
:
:
:
:
Have you got question? Write to us!
:
:
This chat session has ended
Was this conversation useful? Vote this chat session.
Good Bad

ONLINE MESSAGE

Send your inquiry / assessment to Us. Anything need us ,please don’t hesitate contact us here! we will keep it secret for you !