Regenerated high-performance concrete material and preparation method thereof

Abstract

The invention discloses a regenerated high-performance concrete material and a preparation method thereof. The regenerated high-performance concrete material is prepared by pre-wetting treatment of anaggregate, shrinkage-compensating treatment of replacing part of cement with an expanding agent, pouring and vibrating. The regenerated high-performance concrete material comprises the following components in parts by weight: 5-20 parts of cement, 0.5-15 parts of coal ash, 0.5-15 parts of slag powder, 15-45 parts of natural sand, 20-55 parts of a natural stone, 1-10 parts of a regenerated fine aggregate, 5-25 parts of a regenerated coarse aggregate, 5-10 parts of water, 0.2-2 parts of a water reducer and 0.5-5 parts of an expanding agent. The freshly-mixed concrete is good in working performance, an initial slump reaches 210-230 mm, the gradual loss is smaller than 10 mm within 1 hour, and the gas content of the concrete is 4.5-5.5%; when the replacement amount of the regenerated aggregate reaches 50%, the 28-day compressive strength of the prepared regenerated high-performance concrete material reaches 55MPa or over, the electric flux reaches 945 Coulomb (Q-IV level), the 56-day electric flux reaches 675 Coulomb, the 56-day chlorine ion transport coefficient DRCM reaches 1.5*10<-12>m<2> / s, and the mass loss rate of quick freezing and thawing cycle F300 is smaller than 3.5%.

Description

technical field [0001] The invention relates to recycled concrete, which is recycled high-performance concrete, in particular to a method of using expansion agent to compensate shrinkage and aggregate pre-wet treatment technology to prepare recycled high-performance concrete material with high durability, belonging to the field of building materials . Background technique [0002] As the largest building material consumable, concrete materials can be divided into ordinary concrete, high-strength concrete, shotcrete, fiber concrete, high-performance concrete, recycled concrete, etc. according to different classification standards. Among them, recycled concrete is a new concrete prepared by using recycled construction waste aggregates to partially or completely replace natural aggregates such as sand and gravel. While reducing the consumption of natural resources such as sand and gravel, it can also recycle construction waste and reduce pollution. , in line with the national ...

AI Technical Summary

Problems solved by technology

[0005] The technical problem to be solved by the present invention is to provide a recycled high-performance concrete material prepared by using an expansion agent to compensate for shrinkage and aggregate pre-wet treatment for the high water absorption of recycled aggregates, which affects the strength and durability of concrete: Increase the rate of building solid waste recycled aggregates to replace natural sand and gravel aggregates from less than 30% to more than 50%, and the strength, workability, and durability of concrete are not affected or have been improved