A kind of high-performance fiber concrete of c140 strength grade and preparation method thereof

Abstract

The invention discloses a high-performance fiber concrete of C140 strength grade and a preparation method thereof. The mass parts of the concrete are as follows: 465-480 parts of cement, 100-110 parts of water, 730-760 parts of river sand, and 1000 parts of gravel ‑1050 parts, 55‑95 parts of fly ash, 55‑75 parts of rice husk ash, 55‑75 parts of silica fume, 13‑14.5 parts of water reducing agent, 15‑15.5 parts of activator, 1.1‑1.8 parts of cellulose fiber, Hydroxyl-modified carbon nanotube dispersion liquid 30-33 parts, defoamer 2.4-2.5 parts. The prepared concrete has high toughness and excellent durability, and has a high bonding strength with the steel. Its flexural strength is not less than 30.68MPa, the 28d cubic compressive strength is not less than 142.36MPa, and the splitting tensile strength is not less than 12.31MPa, the bonding strength with the steel is not less than 6.04MPa, the unsteady chloride ion migration coefficient D RCM Not larger than 16×10 ‑14 m 2 / s. Used in steel-concrete composite structures, it can effectively exert the synergistic performance between steel and concrete, make up for the poor bonding performance of steel and concrete, and the inability to give full play to their respective mechanical properties.

Description

technical field The invention belongs to the field of new building materials, and is a high-strength, high-toughness and high-durability concrete mixed with rice husk ash, cellulose fibers and modified carbon nanotubes, and specifically relates to a high-toughness high-strength concrete with a C140 strength grade. Performance fiber concrete and method for its preparation. Background technique Ordinary concrete and cement-based materials have low tensile strength and poor toughness, and a large number of micro-cracks will occur during hardening or under external loads, which seriously affect the durability of concrete or cement-based composite structures and reduce the service life of structures. In order to overcome the brittleness of ordinary concrete and high-performance concrete, asbestos fibers, steel fibers, carbon fibers, polyvinyl alcohol fibers, polypropylene fibers, and basalt fibers with toughening effects are used in concrete. The use of a large number of fibers ...

AI Technical Summary

Problems solved by technology

The object of the present invention is to provide a kind of high-performance fiber concrete of C140 intensity grade and preparation method thereof, the present invention uses cellulose fiber, rice husk ash, modified carbon nanotube, cement, fly ash, river sand, crushed stone for the first time , chemical admixtures (including water reducer, activator, defoamer), and water prepared a fiber high performance concrete with high volume stability, high toughness, high durability, and ultra-high strength C140 strength level, overcoming It overcomes the shortcomings of ordinary concrete, such as high brittleness, easy cracking, and poor durability.

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