Concrete micro-expansion reinforcing agent, preparation method thereof, concrete and application thereof

Abstract

The invention provides a concrete micro-expansion reinforcing agent, a preparation method thereof, concrete and application thereof, and the reinforcing agent comprises the following raw materials inpercentage by mass based on the mass of the concrete micro-expansion reinforcing agent: 59.5%-89.7% of quick-hardening sulphoaluminate cement, 10%-40% of anhydrite and 0.3%-0.5% of nano calcium silicate hydrate whisker. The concrete micro-expansion reinforcing agent is prepared by taking high-temperature calcined minerals and natural minerals as main components and compounding a silicate cement mineral activation functional component and a hydration promoting component, and is a concrete performance reinforcing material capable of optimizing cement hydration. The cement hydration degree is improved, the cement hydration product proportion is adjusted, the cement hydration product crystallization configuration is improved, admixture redispersion and hydration are promoted, the effects of shrinkage reduction, compaction, reinforcement, crack resistance, waterproofness and the like are achieved, the compactness, early strength and later strength of concrete can be effectively improved, and the durability of the concrete is obviously improved.

Description

technical field [0001] The invention relates to a concrete micro-expansion reinforcing agent and a preparation method thereof, concrete and application thereof. Background technique [0002] Concrete materials are composed of six parts: ordinary cement, mineral admixtures, sand, stone, admixtures, and water. The silicate minerals formed after hydration of ordinary cement play the role of strength skeleton, so the proportion of cement dosage is closely related to the compressive strength and durability of concrete. However, in the actual application process, with the increase of the proportion of cement in the concrete, a series of problems appeared in the concrete. In large-volume concrete such as road concrete, dam concrete, marine concrete, and tunnel concrete, and in high-grade concrete such as building structures, bridge structures, and special modeling structures, various cracks, defects, and even engineering defects have appeared. The quality problem has seriously af...

AI Technical Summary

Problems solved by technology

In large-volume concrete such as road concrete, dam concrete, marine concrete, and tunnel concrete, and in high-grade concrete such as building structures, bridge structures, and special modeling structures, various cracks, defects, and even engineering defects have appeared. The quality problem has seriously affected the use effect of the actual project, there are potential safety hazards, and some even have major accidents in actual application, causing incalculable losses to the country and the people

[0003] The current technical means are divided into the following four categories: (1) Adding active mineral admixtures (fly ash, mineral powder, pozzolan, etc.) The strength decreases obviously; and when the mineral admixture is excessive, the compressive strength increases slowly, and some even show the phenomenon of insufficient 28d grades, which cannot fundamentally solve the above problems; (2) Adding excessive retarders can delay cement hydration speed, delaying the peak of hydration heat release, but not reducing the total amount of heat release; at the same time, it affects the early strength and later strength of concrete; (3) adding excessive water reducing agent can reduce the water-cement ratio, thereby reducing the amount of cement, ensuring Late Concrete Marking

However, due to the reduction of water-cement ratio, the heat release of concrete is more concentrated; at the same time, the viscosity of concrete increases, and the work performance deteriorates, which is not conducive to the actual operation on the construction site; (4) Adding expansion agent to compensate for shrinkage can reduce shrinkage deformation to a certain extent , but it cannot reduce the heat release of hydration, and even greatly increase the heat release of hydration, making it more concentrated, resulting in temperature cracks

The above four technologies all have shortcomings in varying degrees, and cannot fundamentally solve the problem

[0004] Therefore, it is urgent to propose a cement substitute product to avoid the problem of temperature cracks due to the increase in the proportion of cement in the concrete, the concentration of heat release inside the concrete, and the increase in the temperature difference between the center of the concrete and the surface. The increase of the cement ratio will increase the shrinkage and deformation of the concrete, and the problem of shrinkage cracks will easily occur.

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