Grouting material, premix of grouting material, and preparation method of premix

Abstract

The invention relates to a premix of a grouting material. The premix is characterized in that the premix comprises the following components, by weight, 65-90% of ordinary portland cement with the strength level of 42.5MPa or low alkaline cement with the strength level of greater than 42.5MPa, wherein the water demand for normal consistency is less than 25%, and the tricalcium aluminate content is lower than 8%; 2-29.696% of an ultrafine mineral admixture with a specific surface area of greater than 450m<2> / kg, a water demand ratio of less than 95%, and a 28d activity index of greater than 90%; 5-15% of calcium sulphoaluminate; 0.1-1.5% of a melamine water reducer; 0.002-0.2% of a cellulose polymer, an acrylic polymer or polyoxyethylene; 0.1-1.0% of a carbohydrate, a hydroxycarboxylic acid compound and salts thereof, a sulfate, a carbonate, or calcium formate; 0.002-0.1% of vinyl acetate-ethylene copolymerized rubber powder; and 0.1-1.0% of a chromate or a borate.

Description

technical field [0001] The invention relates to a grouting material and a premix thereof, in particular to a grouting material mainly used in pouring of post-tensioned prestressed structures of railways, highways, and prefabricated bridges, or gap filling of horizontal and vertical pipes, cable gap filling, concrete Gap filling for engineering structures, and a grout for structural sealing, a premix of the grout, and a preparation method thereof. Background technique [0002] At present, the grout applied to the post-tensioned prestressed structure is generally composed of 80-93% of ordinary Portland cement, 1-14% of high-efficiency water reducer and 6-15% of expansion agent, because various admixtures Poor compatibility with cement, poor adaptability between cement and water reducing agent, resulting in many problems such as shrinkage, low strength, low fluidity, bleeding and other problems in the grouting material, which makes the performance indicators of the grouting mate...

AI Technical Summary

Problems solved by technology

[0002] At present, the grout applied to the post-tensioned prestressed structure is generally composed of 80-93% of ordinary Portland cement, 1-14% of high-efficiency water reducer and 6-15% of expansion agent, because various admixtures Poor compatibility with cement, poor adaptability between cement and water reducing agent, resulting in many problems such as shrinkage, low strength, low fluidity, bleeding and other problems in the grouting material, which makes the performance indicators of the grouting material vary; while the imported grouting material Although it can meet the relevant national performance indicators, because the construction requirements and construction methods in my country are different from those in foreign countries, the application of imported grouting materials in domestic construction is not very targeted.

[0003] In addition, at present, most of the domestic grouting materials are prepared on-site at the construction site, and the industrial production of the corresponding grouting premix and grouting materials has not been realized to form finished products; at the same time, due to the complex composition of the grouting materials, the powder added on site There are many body components, the measurement accuracy is very high, the professional quality of construction workers on site is uneven, and the supervision lacks effective quality management methods, it is easy to cause unqualified grouting materials and cannot play the role that prestressed grouting materials should play. , resulting in unqualified pipe grouting quality, grouting is not dense, there are pores or cavities inside the grout, and even the cement grout shrinks and separates from the pipe after hardening, which affects the bonding performance of the grout and prestressed steel bars, and the corrosive substances contact the prestressed steel bars. Steel bars lead to corrosion and damage of prestressed steel bars, so the development of a high-performance, non-shrinkage and anti-corrosion premixed premixed product plays a very important role in promoting the improvement of my country's construction quality

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