Early strength type water reducing agent for precast concrete

Abstract

The invention discloses an early strength type water reducing agent for precast concrete. The early strength type water reducing agent comprises the following components by weight percent: 5.00-6.00% of polycarboxylic acid water reducing agent, 0.50-2.00% of inorganic lithium salt, 1.00-5.00% of inorganic sodium salt, 0.00-10.00% of inorganic calcium salt, 0.01-0.30% of deformer and the balance of filling material. The early strength type water reducing agent has the characteristics that the doped amount is low, the air bleeding is low, the water reduction is high, slump is well maintained, and the early strength is rapidly increased; and by utilizing the early strength type water reducing agent, the steam heating and maintenance of the precast concrete are shortened or avoided, thereby reducing the production cost of the precast concrete.

Description

technical field [0001] The invention relates to the field of building material additives, in particular to an early-strength water reducer for prefabricated concrete. Background technique [0002] In recent years, the construction of major projects such as subways, south-to-north water diversion, west-to-east gas transmission, and passenger dedicated lines, as well as large-scale urban reconstruction, have driven the rapid development of cement concrete materials, and directly led to the demand for prefabricated concrete components such as segments and piles. surge. Taking prestressed high-strength concrete pipe piles (PHC pipe piles for short) as an example, the national output of PHC pipe piles was 20 million m in 1998, 45 million m in 2001, 80 million m in 2003, and 150 million m in 2005. In 2007, the output reached 250 million m, which shows its rapid development. [0003] At present, the water-reducing agent used for precast concrete is mainly naphthalene-based water-...

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Problems solved by technology

[0003] At present, the water-reducing agent used for precast concrete is mainly naphthalene-based water-reducing agent, which has the advantages of low air content and fast strength growth, but the slump loss of concrete prepared with naphthalene-based water-reducing agent is fast, The appearance of the finished product is poor

[0004] CN101200354A discloses a preparation method of concrete super early strength agent, which uses up to 35-55% inorganic early strength components and 5-10% organic early strength components to accelerate the growth of early strength, to promote concrete in In the case of low temperature in winter, it solidifies and hardens quickly. The large amount of inorganic early-strength components in this early-strength agent will greatly reduce the water-reducing rate, which will lead to an increase in the amount of water-reducing components, which will lead to an increase in production costs.

The water reducing agent has the advantages of small dosage, high water reducing rate, low alkali content, and high strength; however, due to the high air-entraining performance of the acrylic polycarboxylate water-reducing Performance, this product is not suitable for the production of concrete precast components, especially the production of concrete precast components using heat curing

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