Ultra-early strength high-performance concrete and preparation method thereof

Abstract

The invention relates to ultra-early strength high-performance concrete and a preparation method thereof. The ultra-early strength high-performance concrete comprises the following components in partsby weight: 700 to 770 parts of cement, 410 to 480 parts of composite mineral admixture, 170 to 190 parts of water, 1180 parts of composite aggregates, 47.2 to 48.0 parts of polycarboxylate superplasticizer, 0.20 to 0.25 parts of defoaming agent and 157 parts of steel fibers, wherein the composite mineral admixture consists of 118 to 177 parts of precipitated fine beads, 59 parts of metakaolin and212.4 to 236 parts of silica fume; and the composite aggregates consist of 514 to 543 parts of China ISO standard sand (medium sand), 255 to 266 parts of 5 to 10 mm basalt crushed stone, and 382 to400 parts of 10 to 16 mm basalt crushed stone. The ultra-early strength high-performance concrete is high in early strength, the compressive strength in 3 days is 120 to 140 MPa, the compressive strength in 7 days is greater than 150 MPa; and the ultra-early strength high-performance concrete has good working performance, has no segregation, bleeding and bottom grabbing, and has self-compacting effect.

Description

technical field [0001] The invention belongs to the technical field of building materials, and in particular relates to a super-early-strength high-performance concrete and a preparation method thereof. Background technique [0002] With the development of modern buildings towards ultra-high-rise, long-span and harsh environment areas (cold areas, saline-alkali areas), and the existence of practical difficulties such as tight construction schedules, heavy tasks, and cost control, super-strength high-performance concrete will become the best choice for concrete development. major trends. In terms of strength alone, the compressive strength of macro-defect-free cement-based materials (MDF), uniformly distributed ultra-fine particle compact system (DSP), and reactive powder concrete (RPC) is very high, but due to the extremely high requirements for the raw materials used in these systems High, such as high-quality cement, inorganic additives, high-quality polymers and even nan...

AI Technical Summary

Problems solved by technology

In terms of strength alone, the compressive strength of macro-defect-free cement-based materials (MDF), uniformly distributed ultra-fine particle compact system (DSP), and reactive powder concrete (RPC) is very high, but due to the extremely high requirements for the raw materials used in these systems High, such as high-quality cement, inorganic additives, high-quality polymers and even nano-materials; the molding process and maintenance process are complex, such as rolling, extrusion, steam curing, autoclaving, etc. In modern construction projects, it is obvious that these materials Cannot be applied on a large scale

[0003] If the existing materials in the ready-mixing plant are used, the concrete formed under conventional technology and under standard curing conditions will often have low 7d strength due to its many internal defects and incomplete early hydration. The strength that can be achieved is generally difficult to exceed 100Mpa

Therefore, the traditional advantages of concrete, such as easy availability of raw materials, simple process, and low cost, actually limit the development of super-strength high-performance concrete to a certain extent, and also restrict its application in engineering

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