Concrete composition and preparation method thereof

Abstract

A concrete composition comprising a binder, water, fine aggregates, coarse aggregates and a mixing agent, a water / binder ratio of 30 to 70 mass %, and a slump flow value of 35 to 75 cm, and a relative To 100 parts by mass of the binder, the concrete composition contains a single-liquid type mixing agent using the following A component, the following B component, the following C component and the following D in a ratio of 0.5 to 3.0 mass parts Components These four components and water, and the ionic strength from the following A component is 0.02 to 0.8. Component A: composed of unsaturated monocarboxylic acid monomers and / or unsaturated dicarboxylic acid monomers and / or their salts, and copolymers with unsaturated monomers that can be copolymerized with them and / or their salts The polycarboxylate water reducing agent is composed, wherein the unsaturated monomer has a polyoxyalkylene group composed of 1 to 300 oxyalkylene units with 2 to 4 carbon atoms in the molecule. Component B: Water-soluble cellulose ether. C component: glue. Component D: antifoaming agent.

Description

technical field [0001] The present invention relates to a concrete composition and a preparation method thereof, and more particularly to a concrete composition with high fluidity and improved material separation resistance, and a preparation method of the concrete composition. Background technique [0002] In recent years, in order to improve workability and save labor, use medium-fluid concrete compositions (slump flow value of about 35 to 50 cm) or high-fluidity concrete compositions (slump flow value of about 50 cm to ), etc. Examples of highly fluid concrete compositions are gradually increasing. As an example, tunnel lining construction is used. When pouring in a small space with poor workability, by using a concrete composition with high fluidity, the high filling property is used to improve workability and save labor for compaction. However, such a highly fluid concrete composition is prone to segregation of materials such as aggregates. Segregation of materials is...

AI Technical Summary

Problems solved by technology

However, the stability of active ingredients such as viscosity-increasing components and water-reducing components in a one-component admixture is very important for the stabilization of the properties and physical properties of concrete compositions. However, as described in Patent Document 4, in In the combination with water reducing agent, cellulose ether is prone to salting out, causing problems such as the loss of stability of the single-liquid admixture in a short period of time

In addition, as described in Patent Document 5, the conventional method of increasing the viscosity of the liquid through a specific glue to stabilize the cellulose ether in the liquid, although it improves the stability of the single-liquid type admixture, is difficult to apply to all general Commercially available water reducing agents, so there are problems such as the need to select water reducing ingredients with low solid content concentration

If a water-reducing component with a low solid content concentration is selected, the water-reducing performance of the single-liquid type admixture will decrease. Especially when preparing a concrete composition with high fluidity, the concrete manufacturer cannot use a measuring device due to the increase in the amount of addition. One-time measurement, etc., which causes reduction in production efficiency of concrete compositions