Admixture for reducing viscosity and shrinkage stress of prefabricated thin-walled concrete and preparation method thereof

Abstract

The invention discloses an admixture for reducing viscosity and shrinkage stress for prefabricated thin-walled concrete and a preparation method thereof. The preparation method of the admixture for reducing the viscosity and shrinkage stress of the prefabricated thin-walled concrete comprises: first, the mineral raw material is crushed, ball milled, calcined, cooled, and ground to form the component A of the powder; Organic raw materials with a specific molar ratio are polymerized, crushed, dried, and pulverized to make powder modified component B; then modify component A with a specific weight portion of modified component B through a liquid coupling agent, Finally, powder component C prepared by reacting, cooling, disintegrating, drying and pulverizing raw materials such as polyethylene glycol methyl ether methacrylate, acrylamide, maleic anhydride and stearyl alcohol is added for mixing. The materials used in the present invention are all pollution-free, and the active components react in the hydration life cycle of the concrete material, and through the hydration cycle of the cement, the micro-expansion, slow release of water, reduce the water loss rate of the concrete, optimize the pore structure of the hardened cement stone, and reduce the capillary pores of the concrete The surface tension of the solution reduces the viscosity and shrinkage stress of the precast thin-walled concrete, thereby improving the constructability and crack resistance of the precast thin-walled concrete mixture.

Description

technical field [0001] The invention belongs to the field of building materials, and relates to an admixture for reducing viscosity and shrinkage stress for prefabricated thin-walled structural concrete and a preparation method thereof. Background technique [0002] Concrete is the largest and most widely used building material in the world today, but its brittle nature makes it poor in crack resistance, and micro-cracks are easily generated during construction or long-term use. The existence and development of these cracks will inevitably affect the performance of concrete structures and reduce the durability and service life of concrete. [0003] Prefabricated prefabricated thin-walled concrete components (fabricated bridge structures) are generally prestressed structures, and their durability risks mainly come from concrete cracking. Due to the process requirements of form removal and tensioning, the strength of thin-walled concrete of prefabricated components is high, a...

AI Technical Summary

Problems solved by technology

[0017] The purpose of the present invention is to provide a preparation method of an admixture that takes into account the effects of reducing viscosity and reducing shrinkage stress in view of the material and construction characteristics of prefabricated thin-walled concrete structures (such as prefabricated box girders, T beams, pier columns, etc.), so as to solve the problem of prefabricated concrete structures. Thin-walled concrete structures have high risk of cracking, high viscosity of concrete mixture, and slow flow speed, etc.

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