Rapid hardening early strength type foam concrete and preparation method thereof

Abstract

The invention discloses rapid hardening early strength type foam concrete and a preparation method thereof. The rapid hardening early strength type foam concrete comprises components with percentage by mass: 20%-40% of composite cement, 15%-25% of water, 5%-10% of b-hemihydrated gypsum, 10%-20% of first-grade fly ash, 5%-15% of S105 activated mineral powder, 3%-5% of condensed silica fume, 5%-15% of polymer emulsion, 0.05%-0.2% of polypropylene fibers, 0.3%-0.5% of polycarboxylate superplasticizer, 0.05%-0.1% of cellulose ethers and 0.05%-0.15% of foaming agents which are mixed and stirred. The rapid hardening early strength type foam concrete is small in contraction, large in flexibility and excellent in subsidence resistance, greatly reduces setting time of foam concrete binding materials, reduces number of foams losing stability along with time, and optimizes structures of inner holes.

Description

technical field [0001] The invention relates to a foam concrete and a preparation method thereof, in particular to a rapid-hardening early-strength foam concrete and a preparation method thereof, belonging to the technical field of engineering materials. Background technique [0002] Foamed concrete is to add high-performance foam prepared by mechanical foaming method into the mixed slurry of cement, magnesite or gypsum and other cementitious materials and filling and functional materials. Or a uniform microporous lightweight material formed after steam curing. A large number of fine pores are evenly distributed in foam concrete, and its bulk density is much lower than that of ordinary concrete. At the same time, foam concrete also has many other excellent properties such as outstanding thermal insulation effect, good sound insulation performance, and excellent seismic performance. Since the foam concrete has no irregular large aggregates in the preparation, under the "ball...

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Problems solved by technology

[0003] Foam in foam concrete is a relatively fragile phase, and its stability is often reduced due to the friction of slurry and mechanical stirring

There are two main problems in foam concrete: one is that foam concrete will produce volume deformation in space, and the lower layer of slurry will be compressed due to the extrusion of the upper layer of slurry; the more commonly used control method is layered pouring, layered Although pouring can prevent volume deformation, it greatly reduces its application efficiency

The second is that the foam concrete cementitious material has a long setting time, and a large amount of foam will burst due to instability, which will seriously affect the performance of foam concrete; the most effective way to solve this problem is to increase the setting speed of the foam concrete cementitious material and shorten its setting. time

[0004] At present, the research on rapid-hardening foam concrete is mainly limited to the use of early-strength agents and hardening-accelerating materials to adjust the setting time of foam concrete. There are few attempts on ultra-fast-hardening foam concrete. The main reason is the lack of effective characterization methods for setting time and the difficulty in determining the foam concrete The state of the slurry during the initial setting of the concrete and the pressure that can withstand the subsequent pouring layer during the final setting are analyzed; in addition, the fast-setting and fast-hardening cementitious materials have higher requirements on the preparation process of foam concrete. Uniform dispersion, no accumulation and hardening at the dead corner of the blade or mixing drum, and the discharge speed of the slurry should be fast, the current mixing process can not well meet its production requirements

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