Ultra-high performance concrete containing metakaolin and preparation method of ultra-high performance concrete

Abstract

The invention relates to ultra-high performance concrete containing metakaolin and a preparation method of the ultra-high performance concrete. The concrete comprises the following components in parts by mass: 750-800 parts of cement, 40-50 parts of silica fume, 450-480 parts of metakaolin powder, 1800-2000 parts of machine-made sand, 25-35 parts of a water reducing agent and 195-205 parts of water, wherein the specific surface area of metakaolin is not less than 800m < 2 > / kg, the ignition loss is not more than 2.5%, the 28d activity index is not less than 115%, and the concrete is obtained by stirring and mixing the raw materials according to the mass parts. Compared with the prior art, the flowability and strength of the freshly mixed concrete are obviously improved, and the durability of the concrete is obviously improved.

Description

technical field [0001] The invention relates to the technical field of building materials, in particular to metakaolin-containing ultra-high performance concrete and a preparation method thereof. Background technique [0002] Due to its high strength, high corrosion resistance and durability, ultra-high performance concrete can reduce the size of the structure, reduce the weight of the structure, save land, reduce energy consumption, reduce structural maintenance costs and reconstruction costs, etc., and its technical development has become a focus of the construction industry. One of the concrete technologies studied and paid attention to. At the same time, with the development trend of high-rise and super-high-rise, long-span, underground and harsh environments in architectural design, ultra-high-performance concrete has outstanding application advantages in large-scale projects such as super-high-rise buildings, cross-sea bridges, and offshore oil production platforms. ....

AI Technical Summary

Problems solved by technology

[0003] Ultra-high-performance concrete generally refers to concrete with a cubic compressive strength greater than 120MPa. However, due to the high cement content, the early-stage hydration heat of ultra-high-performance concrete is high, and shrinkage and cracking are severe. At the same time, due to its low water-cement ratio, ultra-high performance The viscosity of concrete paste is relatively high, and there are certain difficulties in actual construction

With the increasing development of admixture technology and other technologies, various problems highlighted by ultra-high performance concrete have been improved, but have not been completely resolved

[0004] In addition, currently commonly used ultra-high-performance concrete mix ratios require many types of cementitious materials, basically four or more, and the cement used is 52.5 Portland cement, which further limits the application of ultra-high-performance concrete in practical projects. application in