In many concrete engineering projects, traditional high-efficiency concrete such as naphthalene series cannot meet the engineering needs due to the limitations of technical performance. The new generation of water reducing agents, polycarboxylate based high-performance water reducing agents, which have attracted much attention both domestically and internationally, have achieved effective molecular structure design based on the mechanism of dispersed cement action. They have a super dispersed type and can prevent concrete slump loss without causing significant retardation. They have a high plasticizing effect at low dosages, good fluidity retention, large degree of freedom for cement to adapt to wide molecular structures, multiple synthesis technologies, and a lot of room for high-performance development, The significant strengthening effect on concrete, the ability to reduce concrete shrinkage, and the extremely low content of harmful substances endow concrete with excellent construction workability, good strength development, excellent durability, and polycarboxylate based high-performance water reducing agents have good comprehensive technical performance advantages and environmental protection characteristics, which meet the needs of modern concrete engineering.

Therefore, polycarboxylate based high-performance water reducing agents are gradually becoming the preferred admixture for preparing high-performance concrete. According to reports, the use of polycarboxylate additives in Japan accounts for over 80% of all high-performance additive products, and North America and Europe also account for over 50%. In China, polycarboxylate based water reducing agents have been successfully applied only in large-scale water conservancy, bridge, nuclear power, and railway projects such as the Three Gorges Dam, Sutong Bridge, Tianwan Nuclear Power Station, and the Beijing Shanghai high-speed railway, and have achieved significant results.

At the same time, polycarboxylate water reducing agents also have some problems:

1. Insufficient collapse resistance in high-temperature environments;

2. Strong temperature sensitivity, the same type of polycarboxylate water reducing agent has a significant difference in the slump resistance of concrete when constructed in different seasons;

3. There are few functional products, making it difficult to meet the requirements of ultra-high and long-distance concrete pumping, negative temperature construction, preparation of ultra early strength concrete, and high durability of concrete;

4. High viscosity, in the preparation of high admixture and low water cement ratio concrete, the high viscosity of concrete is not conducive to construction;

5. Strong sensitivity to the mud content of sand and gravel aggregates.

6. Poor adaptability to mechanism sand and sensitivity to dosage affect construction.

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