Efficient and safe use of early-strength water-reducing agent can achieve twice the result with half the effort to a certain extent. However, how to use it efficiently has become a problem. Today, the editor of Yulong Company will tell you the method that only senior construction masters know. Everyone, I hope you can use it!
Improve the level of technology, stabilize product quality, and improve technical reserves
According to statistics, there are only a handful of early-strength superplasticizer products in our country. Manufacturing companies independently develop products, while most other manufacturing companies start production by introducing technology from research institutes of universities or research institutes, or by directly introducing technology from other companies. Because the manufacturing company’s own technical energy company has insufficient understanding of the technical aspects of producing early-strength superplasticizers, it is unable to adapt to various changes in raw materials and processes, and it is impossible to ensure stable product quality. rise.
Therefore, it is recommended that early-strength superplasticizer operators actively cooperate with universities and research institutions to fully understand the various risk factors of early-strength superplasticizer product characteristics, and appropriately adjust the generated The main parameters of the processing technology are used to stabilize product quality, and based on collaborative or independent product research and development, the technical reserves are improved and integrated into the market demand. In addition, the early promulgation of early-strength superplasticizer raw material specifications and the reliability of early-strength superplasticizer raw material prices are very important to ensure the reliability of the product properties of early-strength superplasticizers.
I firmly believe that the experimental results are not the product manual
Some products with miraculous instructions for use of superplasticizers, or products with excellent test results, are used in some major engineering projects. On the contrary, although the test results of some products are not very good, they have requirements that may meet the requirements of the concrete material configuration of a certain project. In addition, due to changes in raw materials, experimental results during project bidding may not represent the actual implementation of the project. “2.1.4” in GB50119-2016 “Technical Standard for the Application of Concrete Admixtures” clearly stipulates: Common raw materials for concrete mixed with admixtures such as concrete, sand, stone, admixtures, and admixtures should comply with the relevant specifications of the current standards; When trial mixing concrete mixed with admixtures, the raw materials used in the project should be selected. The inspection project should be confirmed according to the design plan and construction regulations. The inspection standards are the same as the construction standards. When the commonly used raw materials or concrete property requirements of the project change greatly, time, the trial matching experiment should be carried out again.
Prevent early-strength superplasticizers from coming into contact with iron materials
For manufacturers and suppliers of early-strength superplasticizers, special production line equipment and The production line is used to generate and compound early-strength superplasticizers. It cannot be used with other water-reducing agents in the same production line to generate or compound early-strength superplasticizers. In addition, iron materials (not limited to stainless steel) should be used for conveyors and storage of early-strength superplasticizers, but plastics, glass and other materials should be used. Contact with iron sometimes causes changes in the properties of early-strength superplasticizers.
Resolutely prevent the infiltration of other types of admixtures
Prohibiting the infiltration of other water reducing agents or other types of admixtures has a double meaning. First, the compounding of early-strength water-reducing agents (such as with lignosulfonate, air-entraining, demulsifying, retarding and other components) can only be carried out by admixture manufacturers or distributors, and the users of water-reducing agents must not That is to say, the concrete manufacturer only needs to inspect the relevant properties of the concrete before it is put into storage, and is not allowed to mix any other components into it, nor is it allowed to infiltrate other components carelessly. Pumps and metering equipment that use underwater concrete and other additives without cleaning are strictly prohibited. Another implication is that concrete mixing station equipment, vehicle transportation, and underwater concrete equipment should preferably be fixed with concrete mixed with early-strength water-reducing admixtures. Mixing machinery, transportation vehicles, and underwater concrete machinery should be used together. During installation, these equipment must be completely cleaned before they can be used as concrete mixed with other types of admixtures, and vice versa.
Strict measurement and verification of water-reducing agents and mixing water
When preparing concrete mixtures mixed with early-strength superplasticizers, the best reduction methods confirmed by the laboratory should be strictly followed. When measuring and verifying the amount of water agent used and water demand, do not increase the amount of water reducing agent or water demand arbitrarily to prevent the mixed concrete from experiencing adverse phenomena such as concrete segregation, bleeding, agglomeration, and increased air content, which will affect the normal performance of the concrete. Underwater concrete engineering construction and concrete pouring quality. The moisture contained in the raw material sand and stone asphalt mixture must be accurately measured and deducted from the total water demand to avoid adverse effects caused by prohibition of moisture detection in the sand and stone asphalt mixture.
Properly deal with the adaptability problem of early-strength superplasticizers and concrete/admixtures
The adaptability problem of admixtures and concrete/admixtures has become increasingly prominent. Over the years, the research on the adaptability of naphthalene-based superplasticizers and compound products has achieved very good results: first of all, through diligent publicity and planning based on academic research, concrete producers, admixture operators, Concrete and admixture operators, concrete pourers and project supervisors understand each other and understand this problem, which has changed the traditional production process of admixtures.The manufacturer and supplier bear any responsibility; secondly, the problem of incompatibility between admixtures and concrete/admixtures is attributed to many hazardous factors, and the regularity of their hazards is analyzed in depth; thirdly, , a series of reasonable solutions have been explored for the main incompatibility issues between admixtures and concrete/admixtures.
The addition of early-strength water-reducing admixtures should follow expert guidance and undergo rigorous testing
According to GB50119-2016 “Technical Standard for the Application of Concrete Admixtures”, when mixed into underwater When transporting the concrete from the ready-mixed concrete plant to the concrete pouring site, the slump of the concrete will be too great due to long distances, congestion, or long waiting times for concrete pouring, making it unsuitable for underwater concrete or concrete pouring. During construction, you can use the method of adding underwater concrete agent again. Add a sufficient amount of underwater concrete agent to the concrete and transport it to the concrete mixer truck for rapid operation until the mixing is even. After measuring the slump to meet the requirements, proceed with underwater concrete and Concrete pouring. It should be noted that when the slump loss of concrete mixed with early-strength water-reducing admixture is too great because it cannot be broken, the method of adding water-reducing admixture again can be used to restore the fluidity of the concrete to avoid causing The extravagant waste of concrete mix. However, the characteristics of the concrete mixture are quite sensitive to the dosage of early-strength superplasticizer. If it is too much, it will easily cause concrete to segregate, bleed, and even become layered. Moreover, the addition of early-strength superplasticizer will have a negative impact on the concrete. The specific hazards have basically not been studied scientifically. </p
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