Common Problems and Countermeasures of Polycarboxylate Superplasticizer in Use

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New Earth Group


Common Problems and Countermeasures of Polycarboxylate Superplasticizer in Use

At present, our concrete industry commonly used admixture hasPolycarboxylate superplasticizer, naphthalene, naphthalene and amine complex, naphthalene and aliphatic complex, aliphatic system. All kinds of admixture has its advantages and disadvantages. With the improvement of polycarboxylic acid admixture technology and the decrease of manufacturing cost, its application scope is rapidly expanding. Polycarboxylic acid high efficiency pumping agent as the representative of the third generation of water reducing agent in our country, compared with the wood calcium as the representative of the first generation of water reducing agent and naphthalene series as the representative of the second generation of water reducing agent, with high water reducing rate, high slump retention, high enhancement and other advantages. Especially suitable for the preparation of high durability, large fluidity, high slump, high strength and water concrete engineering. However, it requires high quality and production process of concrete raw materials, and is particularly sensitive to the mud content of aggregates and the temperature of cementitious materials, so attention should be paid to it in the actual use process.
Polycarboxylic acid pumping agent still exists with the problem of cement adaptability, for individual cement will appear low water reduction rate, slump larger phenomenon, so when the pumping agent and cement adaptability should be on the polycarboxylic acid pumping agent formula and adjust its components, in order to achieve the best effect. In addition, the fineness, temperature and storage time of cement will also affect the use of polycarboxylic acid pumping agent.
Polycarboxylic acid pumping agent is sensitive to the change of raw materials, when the quality of sand, stone materials and admixtures such as fly ash, mineral powder and other raw materials change greatly, it will have a significant impact on the performance of concrete mixed with polycarboxylic acid pumping agent, and should be re-tested with the changed raw materials to adjust the dosage to achieve the best effect.
Polycarboxylic acid pumping agent because of the high water reduction rate, the concrete slump is particularly sensitive to water consumption. Therefore, in the use of the process must strictly control the amount of polycarboxylic acid pumping agent and concrete water consumption. Once the excess, the concrete will appear segregation, bleeding slurry, the bottom of the plate and the air content is too large and other undesirable phenomena.

Key words:

Polycarboxylate superplasticizer