Superplasticizer is increasingly widely used and is a de facto requirement for the transformation of building structures and processes. In recent years, top floors, large spans and various new structural mechanisms have appeared in overall precast concrete structures. Many new bearing forms such as large and medium-sized and thick walls have appeared in prefabricated precast concrete bearings. In concrete New construction techniques such as large-volume concrete, sprayed concrete, positive air moisture-absorbing concrete, and slip-form construction concrete have emerged during pouring. Therefore, concrete has the characteristics of large fluidity, early strength, high strength, rapid setting, slow setting, and low temperature. Various properties such as heat of hydration, cold resistance, and waterproof concrete are required. The use of water-reducing admixtures is to improve the properties of concrete, improve construction quality, reduce project budgets, and promote production process requirements. The properties of concrete are determined by the proportions of concrete, sand, stone and water.
In order to improve certain properties of concrete, the proportion of raw materials can be adjusted. But that would therefore lead to damage at the same time. For example, in order to increase the fluidity of concrete, the amount of water can be increased, but this will reduce the strength of the concrete. In order to increase the initial strength of the concrete, the concrete dosage can be increased, but in addition to increasing the profit, this will also increase the shrinkage and creep of the concrete. The use of water-reducing admixtures can avoid the above-mentioned shortcomings. The use of concrete admixtures can greatly improve certain properties of concrete while having little impact on other properties of concrete.
For example, if 0.2% to 0.3% calcium lignosulfonate water-reducing agent is added to concrete, it can be added without increasing the water dosage. Increase the slump of concrete by several times; if 2% to 4% sodium sulfate calcium (NC) coating agent is added to the concrete, the initial strength of the concrete can be increased by 60%~ without increasing the concrete dosage. 70%, and the final strength of the concrete must be improved.
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