A kind of fair-faced concrete and preparation method thereof

Abstract

The invention discloses a fair-faced concrete, which is characterized in that it is made of the following raw materials in parts by weight: 5-10 parts of surface-modified nano-boron fibers, 5-10 parts of kaolin, 10-15 parts of illite powder, and 20 parts of gravel ‑30 parts, 5‑10 parts of vermiculite sand, 20‑30 parts of fine sand, 40‑50 parts of Portland cement, 1‑5 parts of composite additives, 20‑30 parts of water. The composite additive includes the following components by weight: 20-25 parts of phosphate-based boric acid-based copolymer, 2-5 parts of zinc citrate, 1-3 parts of pyrophyllite powder, 1-3 parts of wollastonite powder, porous silicon Magnesium acid 2-4 parts, defoamer 0.5-1 part, polyaminopropyl biguanide 0.8-1.5 parts, hydroxypropyl cyclodextrin 0.5-2 parts, activator 1-3 parts, water 80-100 parts. The invention also discloses a preparation method of the fair-faced concrete. The fair-faced concrete disclosed by the invention has high compressive strength, good corrosion resistance, impermeability and crack resistance, excellent comprehensive performance, and safe and environment-friendly production and use.

Description

technical field [0001] The invention relates to the technical field of building materials, in particular to a fair-faced concrete and a preparation method thereof. Background technique [0002] With the development of my country's construction industry technology level, the rise of green buildings, low-carbon buildings, ecological buildings, etc., fair-faced concrete has attracted widespread attention for its natural texture and no need for decoration and decoration, and has gradually been used in subways and high-speed railways. , highways, bridges and culverts, high-rise buildings, and water conservancy dams. Compared with ordinary concrete, fair-faced concrete belongs to one-time pouring molding concrete, without any external decoration, and directly adopts the natural surface effect of cast-in-place concrete as the finish, with uniform color, smooth surface, no honeycomb pitting, sharp edges and corners, and no bumps. In addition, since the fair-faced concrete structure ...

AI Technical Summary

Problems solved by technology

The existing fair-faced concrete mix ratio design is carried out with the ordinary concrete mix ratio design method, and the mixing amount of various ingredients is adjusted as appropriate, resulting in rough and uneven surfaces of the poured clear-water concrete, large color differences, and large pores and gaps. Large and unevenly distributed, or while obtaining the surface quality, the strength of the concrete cannot be guaranteed. The fair-faced concrete designed by this design method has more or less cement-based efflorescence, color changes of cast-in-place concrete, and existing Pouring fair-water concrete is rigid, easy to crack, and imitation fair-water concrete dry powder mortar cracking technical problems

[0004] In the prior art, domestic production of clear-water concrete usually uses natural river sand and pebbles as coarse and fine aggregates, and after mixing with cement, mineral admixtures, water-reducing agents, water, etc., a certain amount of defoamer is added to produce clear-water concrete. This method consumes a large amount of river sand resources and seriously damages the environment, and the addition of defoaming agent still cannot eliminate the air bubbles on the surface of fair-faced concrete. After the concrete components are demolished, the surface finish cannot meet the requirements, which makes many projects generate repeated decoration engineering costs.