CN115321867B - Nontoxic modified silica powder reinforced concrete powder compacting agent and preparation method thereof - Google Patents

Abstract

The invention discloses a nontoxic modified silica powder reinforced concrete powder compacting agent, which comprises the following raw material components in parts by mass: 10-20 parts of ethylenediamine acetate, 10-20 parts of sodium aminotriacetate and 10-15 parts of sodium aminotrimethylene phosphonate; 5-10 parts of modified silicon powder; 35-65 of carrier. The modified silicon powder is ammonium humate modified silicon powder. The carrier is one or a combination of fly ash, mineral powder, stone powder and zeolite powder. The reinforced concrete powder compacting agent provided by the invention is a compacting agent which does not contain volatile organic compounds and can improve the durability and the strength of the concrete at all ages.

Description

Nontoxic modified silica powder reinforced concrete powder compacting agent and preparation method thereof

Technical Field

The invention belongs to the technical field of concrete production, and particularly relates to a nontoxic modified silica powder reinforced concrete powder compacting agent and a preparation method thereof.

Background

The concrete compacting agent is a chemical additive for improving the durability and performance of concrete, is easy to dissolve in water, is uniformly distributed in the concrete after being stirred, and is subjected to chemical reaction with cement hydration precipitate to generate crystals and gel, so that the volume shrinkage of the concrete is reduced, and the crack resistance of the concrete is improved. Meanwhile, in the growth process of the gel, the pores in the cement stone are filled and blocked, and the communication of the capillary channels is cut off, so that the porosity in the concrete is reduced, and the compactness and the impermeability are improved. The concrete compacting agent is used as a product in the concrete industry chain and is one of the indispensable raw materials in the production process of a plurality of concrete production enterprises. The concrete anti-seepage agent can bring substantial benefits to concrete enterprises, and has the main effects of obviously improving the anti-seepage performance of concrete, reducing shrinkage and preventing cracking, effectively preventing water molecules from penetrating, and obviously improving the strength of the concrete. In recent years, with the progress of concrete production technology and the increase of the use amount of concrete, the technical standard of concrete compactors is also higher and higher.

The most common concrete compacting agent at present is that silica fume is directly added into concrete to serve as the compacting agent, and the concrete compacting agent has the advantages of low cost, convenience in processing and the like. However, in the use process, the concrete has poor durability, reduced mechanical strength and risk of cracking due to large specific surface area of silica fume, large water demand and poor cement adaptability. Another concrete compacting agent is silica powder doped with a waterproof agent and an expanding agent. Most waterproofing agents and swelling agents contain volatile organic compounds, which are potentially harmful to the health of workers. In addition, the addition of the compacting agent of the waterproofing agent and the expanding agent can influence the hydration reaction of the cement, thereby reducing the strength of the concrete. Therefore, the powder compacting agent which does not contain volatile organic compounds and can improve the durability and the strength of the concrete at all ages is needed to be prepared.

The silicon powder is a byproduct of aluminum fluoride production by a wet method, is an inorganic nonmetallic material which is nontoxic, odorless and pollution-free, and is micro powder formed by processing amorphous SiO2 through a plurality of processes such as crushing, ball milling, flotation, acid washing purification, high purity water treatment and the like. The surface of the silicon powder modified by the ammonium salt is wrapped by the ammonium salt, so that the water demand is reduced, the dispersibility is better, and the silicon powder can be easily and uniformly dispersed in the concrete stirring process. The powder compacting agent prepared from the modified silica powder does not contain volatile organic matters, can be used for filling holes and gaps in concrete, and can be used for improving the durability and the strength of the concrete in all ages.

Disclosure of Invention

Aiming at the defects of the prior art, the invention aims to provide a nontoxic modified silica powder reinforced concrete powder compacting agent and a preparation method thereof, so as to solve the problems in the prior art.

The aim of the invention can be achieved by the following technical scheme:

the nontoxic modified silica powder reinforced concrete powder compacting agent comprises the following raw material components in parts by mass: 10-20 parts of ethylenediamine acetate, 10-20 parts of sodium aminotriacetate and 10-15 parts of sodium aminotrimethylene phosphonate; 5-10 parts of modified silicon powder; 35-65 of carrier.

Preferably, the modified silicon powder is ammonium humate modified silicon powder.

Preferably, the preparation method of the ammonium humate modified silicon powder comprises the following steps:

s1: dispersing 1 part of silicon powder in 50-120 parts of deionized water, and performing ultrasonic dispersion for 20-45min;

s2: adjusting the pH to 1-2;

s3: stirring at room temperature, dropwise adding 4-6 parts of ammonium humate aqueous solution, and carrying out modification reaction for 24 hours;

s4: washing the product of S3 to neutrality by using absolute ethyl alcohol and deionized water;

s5: drying in a vacuum drying oven at 50-70 ℃ for 48 hours to obtain modified silicon powder.

The preparation method of the nontoxic modified silica powder reinforced concrete powder compacting agent comprises the following steps:

t1: selecting modified silicon powder in a carrier, and crushing for 5-10min by an electromagnetic crusher;

t2: sequentially adding ethylenediamine acetate, sodium aminotriacetate and sodium aminotrimethylene phosphonate according to a proportion, blending for 10-20min, standing for 24 hours, and cooling to obtain the concrete powder compacting agent.

Preferably, the carrier is one or a combination of fly ash, mineral powder, stone powder and zeolite powder. The invention has the beneficial effects that:

firstly, the concrete powder compacting agent disclosed by the invention does not contain volatile organic matters and is harmless to human bodies;

secondly, the concrete powder compacting agent contains a large number of hydroxyl groups and amino groups with stronger polarity, is easy to adsorb on the surfaces of silicon powder particles, neutralizes charges among the silicon powder particles, and can improve the durability of the concrete when being doped into the concrete;

thirdly, the concrete powder compacting agent disclosed by the invention can improve the strength of concrete at each age. After the concrete powder compacting agent is added during concrete stirring, the compressive strength and the flexural strength of the concrete can be obviously improved.

In summary, the concrete powder compacting agent provided by the invention is nontoxic, and can not only improve the durability of concrete, but also improve the mechanical property of concrete.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described, and it will be obvious to those skilled in the art that other drawings can be obtained according to these drawings without inventive effort.

FIG. 1 is a scanning electron microscope image of modified silicon powder;

fig. 2 is a comparative table of the properties of example 1, example 2, comparative example 1, comparative example 2.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

In the description of the present invention, it should be understood that the terms "open," "upper," "lower," "thickness," "top," "middle," "length," "inner," "peripheral," and the like indicate orientation or positional relationships, merely for convenience in describing the present invention and to simplify the description, and do not indicate or imply that the components or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the present invention.

Embodiment one:

the nontoxic modified silica powder reinforced concrete powder compacting agent comprises the following raw material components in percentage by mass: 13% of ethylenediamine acetate, 15% of sodium aminotriacetate, 12% of sodium aminotrimethylene phosphonate, 6% of modified silicon powder and 54% of fly ash.

The preparation method of the nontoxic modified silica powder reinforced concrete powder compacting agent comprises the following steps:

t1: mixing the modified silicon powder with a carrier, and crushing for 5-10min by an electromagnetic crusher;

t2: sequentially adding ethylenediamine acetate, sodium aminotriacetate and sodium aminotrimethylene phosphonate, carrying out blending reaction for 10-20min,

t3: standing for 24 hours, and cooling to obtain the concrete powder compacting agent.

The preparation method of the modified silicon powder comprises the following steps:

s1: 1 part of silicon powder is dissolved in 50-120 parts of deionized water, and ultrasonic dispersion is carried out for 20-45min;

s2: adjusting the pH to 1-2;

s3: stirring at room temperature, dropwise adding 4-6 parts of ammonium humate aqueous solution, and carrying out modification reaction for 24 hours;

s4: washing the product obtained in the step S3 to be neutral by using absolute ethyl alcohol and deionized water;

s5: drying in a vacuum drying oven at 50-70 ℃ for 48 hours to obtain modified silicon powder.

Embodiment two:

the nontoxic modified silica powder reinforced concrete powder compacting agent comprises the following raw material components in percentage by mass: 13% of ethylenediamine acetate, 15% of sodium aminotriacetate, 12% of sodium aminotrimethylene phosphonate, 8% of modified silicon powder and 52% of mineral powder.

The preparation method of the nontoxic modified silica powder reinforced concrete powder compacting agent comprises the following steps:

t1: mixing the modified silicon powder with a carrier, and crushing for 5-10min by an electromagnetic crusher;

t2: sequentially adding ethylenediamine acetate, sodium aminotriacetate and sodium aminotrimethylene phosphonate, carrying out blending reaction for 10-20min,

and T3, standing for 24 hours, and cooling to obtain the concrete powder compacting agent.

The preparation method of the modified silicon powder comprises the following steps:

s1: 1 part of silicon powder is dissolved in 50-120 parts of deionized water, and ultrasonic dispersion is carried out for 20-45min;

s2: adjusting the pH to 1-2;

s3: stirring at room temperature, dropwise adding 4-6 parts of ammonium humate aqueous solution, and carrying out modification reaction for 24 hours;

s4: washing the product obtained in the step S3 to be neutral by using absolute ethyl alcohol and deionized water;

s5: drying in a vacuum drying oven at 50-70 ℃ for 48 hours to obtain modified silicon powder.

Experimental comparison of the examples of the present invention and comparative examples:

comparative example 1: certain commercial waterproof compacting agent is added in an amount of 0.15% of the total amount of the concrete.

Comparative example 2: some commercial powder siliceous compactors are added in an amount of 0.15% of the total amount of the concrete.

The concrete proportion with the reference number of C40 is selected, the compacting agents of the examples 1 and 2 and the comparative examples 1 and 2 are respectively added, and the addition amount of the compacting agents is 0.15 percent of the total amount of the concrete cementing material. Concrete impermeability and mechanical properties are tested, and specific test results are shown in a table in FIG. 1.

As can be seen from the experimental data of the table in fig. 1, the concrete powder compacting agent provided by the invention has the advantages of less water demand and capability of remarkably improving the durability and the flexural compression strength of concrete.

In the description of the present specification, the descriptions of the terms "one embodiment," "example," "specific example," and the like, mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The foregoing has shown and described the basic principles, principal features and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, and that the above embodiments and descriptions are merely illustrative of the principles of the present invention, and various changes and modifications may be made without departing from the spirit and scope of the invention, which is defined in the appended claims.

Claims (3)

1. The nontoxic modified silica powder reinforced concrete powder compacting agent is characterized by comprising the following raw material components in parts by mass: 10-20 parts of ethylenediamine acetate, 10-20 parts of sodium aminotriacetate and 10-15 parts of sodium aminotrimethylene phosphonate; 5-10 parts of modified silicon powder; 35-65 parts of a carrier;

the modified silicon powder is ammonium humate modified silicon powder;

the preparation method of the ammonium humate modified silicon powder comprises the following steps:

s1: dispersing 1 part of silicon powder in 50-120 parts of deionized water, and performing ultrasonic dispersion for 20-45min;

s2: adjusting the pH to 1-2;

s3: stirring at room temperature, dropwise adding 4-6 parts of ammonium humate aqueous solution, and carrying out modification reaction for 24 hours;

s4: washing the product of S3 to neutrality by using absolute ethyl alcohol and deionized water;

s5: drying in a vacuum drying oven at 50-70 ℃ for 48 hours to obtain modified silicon powder.

2. The reinforced concrete powder compacting agent of claim 1, wherein the carrier is one or a combination of fly ash, mineral powder, stone powder, zeolite powder.

3. The method for preparing the nontoxic modified silica powder reinforced concrete powder compacting agent as claimed in claim 1, wherein the preparation method comprises the following steps:

t1: selecting modified silicon powder in a carrier, and crushing for 5-10min by an electromagnetic crusher;

t2: sequentially adding ethylenediamine acetate, sodium aminotriacetate and sodium aminotrimethylene phosphonate according to a proportion, blending for 10-20min, standing for 24 hours, and cooling to obtain the concrete powder compacting agent.