CN108101406B - A kind of super early strength concrete early strength agent and preparation method thereof - Google Patents

Abstract

The invention provides an early-strength concrete early-strength agent and a preparation method thereof. In parts by weight, the concrete early strength agent includes the following components: water, 860-880 parts; diethylene glycol monobutyl ether, 70-75 parts; polyethylene glycol, 40-45 parts; isopropyl alcohol, 10 parts ‑20 parts; soluble inorganic salt solution, 1850‑1950 parts; alkaline conditioner, 5‑5.5 parts. The soluble inorganic salt solution is composed of liquid A and liquid B, and liquid A: liquid B = 1: 1; liquid A is a soluble calcium salt solution, and liquid B is a soluble silicate solution. Using the early-strength agent provided by the present invention can make concrete 8h compressive strength reach more than 60% of the design strength under normal temperature and normal pressure and humidity 95% curing, shorten the demoulding time, speed up the mold turnover speed, and the strength will not shrink in the later stage. . The preparation method of the invention is easy to operate, and only needs to add all the raw material components in different orders, stir and disperse evenly, eliminates the steaming and autoclaving process in the prior art, and saves energy and reduces consumption.

Description

A kind of super early strength concrete early strength agent and preparation method thereof

technical field

The invention relates to the technical field of concrete admixtures, and particularly relates to a super-early-strength concrete early-strength agent and a preparation method thereof.

Background technique

In recent years, with the rapid development of housing industrialization in my country, the demand for prefabricated components has gradually increased. Nowadays, prefabricated components are mostly produced by molds. In order to improve production efficiency and speed up the turnover of molds, concrete needs to have high strength in a short time. But at present, to achieve this strength index, it is necessary to adopt the process of steam curing and pressure steaming. This operation process increases equipment investment and energy consumption, and at the same time, the working cycle is long and the operation process is complicated. In addition, the prefabricated component industry uses a lot of naphthalene-based superplasticizers. Even if polycarboxylate superplasticizers are used, ordinary polycarboxylate superplasticizers are generally compounded with inorganic salts with early strength properties to achieve early strength. effect, but it is still difficult to get rid of the process of steaming and steaming.

Therefore, the preparation of an early strength agent with excellent super early strength effect, good concrete durability, and no steam curing and autoclaving will play a very important role in energy saving and emission reduction in the precast concrete industry.

SUMMARY OF THE INVENTION

The purpose of the present invention is to overcome the deficiencies in the above-mentioned prior art, and propose a super-early-strength concrete early-strength agent and a preparation method thereof.

In order to achieve the above object, the present invention provides the following technical solutions:

A super early-strength concrete early-strength agent, in parts by weight, the concrete early-strength agent comprises the following components: water, 860-880 parts; diethylene glycol monobutyl ether, 70-75 parts; polyethylene Diol, 40-45 parts; isopropanol, 10-20 parts; soluble inorganic salt solution, 1850-1950 parts; alkaline conditioner, 5-5.5 parts.

In the concrete early-strength agent as described above, preferably, the soluble inorganic salt solution is composed of liquid A and liquid B, and liquid A:liquid B=1:1; the liquid A is a soluble calcium salt solution, and the liquid B For soluble silicate solution.

In the concrete early-strength agent as described above, preferably, the liquid A is a soluble calcium salt solution prepared from a soluble calcium salt and water at a ratio of 1:4-6.

As mentioned above, the concrete early strength agent, preferably, the soluble calcium salt is calcium nitrate tetrahydrate and/or calcium formate; preferably, the soluble calcium salt is calcium nitrate tetrahydrate and calcium formate, and the ratio of the two is 1:3-6.

As for the concrete early strength agent as mentioned above, preferably, the liquid B is a soluble silicate solution prepared by soluble silicate and water at a ratio of 1:3.5-4.5.

The concrete early strength agent as described above, preferably, the soluble silicate is sodium metasilicate nonahydrate and/or sodium silicate; preferably, the soluble silicate is sodium metasilicate nonahydrate and Sodium silicate; and the ratio of the two is 1:2-5.

As for the concrete early-strength agent as described above, preferably, the alkaline modifier is triethanolamine.

A kind of preparation method of concrete early strength agent as above, described preparation method comprises the steps:

1) According to the proportioning design of the raw materials of each component, measure and take them for later use;

2) the water, diethylene glycol monobutyl ether, polyethylene glycol and isopropanol weighed in step 1) are put into the reactor, mixed and stirred until completely dissolved;

3) under normal temperature situation, in the solution obtained in step 2), add liquid A and liquid B in equal parts by weight respectively while stirring;

4) After the dropwise addition in step 3), an alkaline regulator is added to the mixed solution, and the stirring is continued for 0.2-1 h, and the mixed solution in the reaction kettle is neutralized to a pH of 7-8 to obtain an ultra-early-strength concrete. Strong agent.

In the above-mentioned preparation method of concrete early strength agent, preferably, in step 3), the dropping rates of the A liquid and the B liquid are 1.5-2.0 kg/h.

In the above-mentioned preparation method of concrete early strength agent, preferably, in step 4), continue stirring for 0.5h.

Compared with the closest prior art, the technical solution provided by the present invention has the following beneficial effects:

1. The present invention utilizes calcium salts and silicates to obtain nanoscale calcium silicate particles by adjusting the Ca/Si ratio and under the action of a dispersant, and this early strength agent provides a crystal nucleus class inducer in the initial stage of cement hydration, Reduce the nucleation barrier of cement hydration products, speed up the hydration process of hydration products, and then improve the early strength of cement-based materials, but will not cause later strength collapse.

2. The 8h compressive strength of concrete can reach more than 60% of the design strength by using the early strength agent provided by the present invention under normal temperature and pressure and humidity of 95%, shortening the demoulding time, speeding up the mold turnover rate, and the later strength will not occur. shrink back.

3. The preparation method of the present invention is simple and easy to operate, and only needs to add all the raw material components into the reaction kettle according to different orders, stir and disperse evenly, eliminate the steaming and autoclaving process in the prior art, and save energy and reduce consumption.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art fall within the protection scope of the present invention.

Specific embodiments of the present invention provide a super-early-strength concrete early-strength agent and a preparation method thereof. In the technical scheme of the present invention, water, diethylene glycol monobutyl ether, polyethylene glycol, isopropanol, etc. are put into the reaction kettle, stirred until dissolved, and at normal temperature, the prepared liquid A is added dropwise to it at the same time. and B liquid, add alkaline regulator to neutralize to pH 7-8, and obtain super early strength concrete early strength agent. The preparation process of the early strength agent is simple, it can induce the hydration of cement to form C-S-H gel, reduce the activation energy of hydration reaction, and promote the rapid development of strength during the hardening period. The 8h compressive strength of concrete can reach 8h after curing at normal pressure of 30°C and humidity of 95%. The strength of ordinary concrete of the same strength grade is more than 3d, the demoulding time is shortened, the mold turnover speed is accelerated, and the strength will not shrink in the later stage; in addition, the concrete early strength agent of the present invention can shorten or even eliminate the steam curing and autoclaving process of the prefabricated concrete components. ,Energy saving.

First, a kind of super early-strength concrete early-strength agent provided by the invention, in parts by weight, the concrete early-strength agent comprises the following components:

Water, 860-880 parts (e.g. 863 parts, 865 parts, 868 parts, 870 parts, 872 parts, 874 parts, 876 parts, 878 parts, 879 parts); Diethylene glycol monobutyl ether, 70-75 parts (e.g. 71 parts, 71.5 parts, 72 parts, 72.5 parts, 73 parts, 73.5 parts, 74 parts, 74.3 parts, 74.8 parts); polyethylene glycol, 40-45 parts (eg 41 parts, 41.5 parts, 42 parts, 42.5 parts) , 43 parts, 43.5 parts, 44 parts, 44.3 parts, 44.8 parts); isopropanol, 10-20 parts (eg 11 parts, 12 parts, 13 parts, 14 parts, 15 parts, 16 parts, 17 parts, 18 parts) , 19 parts); soluble inorganic salt solution, 1850-1950 parts (eg 1855 parts, 1860 parts, 1865 parts, 1870 parts, 1875 parts, 1880 parts, 1890 parts, 1900 parts, 1910 parts, 1920 parts, 1930 parts, 1940 parts) parts); alkaline conditioner, 5-5.5 parts (eg 5.1 parts, 5.15 parts, 5.2 parts, 5.25 parts, 5.3 parts, 5.35 parts, 5.40 parts, 5.45 parts, 5.50 parts, 5.54 parts).

Wherein, the soluble inorganic salt solution is composed of liquid A and liquid B, and liquid A: liquid B = 1:1; liquid A is a soluble calcium salt solution, and liquid B is a soluble silicate solution.

In a specific embodiment of the present invention, it is further preferred that the liquid A is a soluble calcium salt and water in a ratio of 1:4-6 (for example, 1:4, 1:4.5, 1:5, 1:5.5, 1:5.7, 1:5. 5.8, 1:5.9) soluble calcium salt solution. Still preferably, the soluble calcium salt is calcium nitrate tetrahydrate and/or calcium formate.

Preferably, the soluble calcium salts are calcium nitrate tetrahydrate and calcium formate, and the two can be in any ratio. Still preferably, the soluble calcium salts are calcium nitrate tetrahydrate and calcium formate, and the ratio of the two is 1:3-6 (for example, 1:3, 1:3.5, 1:4, 1:4.5, 1:5, 1:5.5 , 1:5.9).

In a specific embodiment of the present invention, it is further preferred that liquid B is soluble silicate and water in a ratio of 1:3.5-4.5 (for example, 1:3.6, 1:3.7, 1:3.8, 1:3.9, 1:4, 1 : 4.1, 1: 4.2, 1: 4.3, 1: 4.4) soluble silicate solution. Still more preferably, the soluble silicate is sodium metasilicate nonahydrate and/or sodium silicate.

Preferably, the soluble silicates are sodium metasilicate nonahydrate and sodium silicate, and the two can be in any ratio. Still preferably, the soluble silicate is sodium metasilicate nonahydrate and sodium silicate, and the ratio of the two is 1:2-5 (for example, 1:2.5, 1:2.8, 1:3, 1:3.5, 1 : 4, 1: 4.5, 1: 4.6, 1: 4.7, 1: 4.8).

In a specific embodiment of the present invention, the alkaline modifier is preferably triethanolamine.

In addition, the present invention also provides a preparation method of the above concrete early strength agent, and the preparation method comprises the following steps:

1) According to the proportioning design of the raw materials of each component, measure and take them for later use;

2) the water, diethylene glycol monobutyl ether, polyethylene glycol and isopropanol weighed in step 1) are put into the reactor, mixed and stirred until completely dissolved;

3) Under normal temperature (20-30 ℃) and normal pressure, in the process of mixing and stirring in step 2), add the prepared liquid A and liquid B in equal parts by weight at the same time, and continue to drop at a rate of 1.5-2.0kg/ h (eg 1.55kg/h, 1.60kg/h, 1.65kg/h, 1.70kg/h, 1.75kg/h, 1.8kg/h, 1.85kg/h, 1.9kg/h, 1.95kg/h);

4) After the dropwise addition in step 3) is completed, add an alkaline regulator to the mixed solution, and continue to stir for 0.2-1h (eg 0.3h, 0.4h, 0.5h, 0.6h, 0.7h, 0.8h, 0.9h, 0.95h) h), neutralize the mixed solution in the reaction kettle to a pH of 7-8 to obtain a super-early-strength concrete early-strength agent.

Example 1:

In parts by weight, 860 parts of water, 75 parts of diethylene glycol monobutyl ether, 45 parts of polyethylene glycol, and 20 parts of isopropanol were put into the reactor, and stirred until completely dissolved; At the same time, 930 parts of liquid A prepared with an equal weight of calcium nitrate tetrahydrate and water in a ratio of 1:5 and 930 parts of liquid B prepared with sodium metasilicate nonahydrate and water in a ratio of 1:4 were added dropwise for 4 hours. Add 5 parts of alkaline regulator triethanolamine for neutralization and adjustment to obtain an early-strength concrete early-strength agent.

Example 2:

In parts by weight, put 870 parts of water, 70 parts of diethylene glycol monobutyl ether, 45 parts of polyethylene glycol, and 15 parts of isopropanol into the reactor, and stir until completely dissolved; At the same time, 925 parts of liquid A prepared with equal parts by weight of calcium formate and water in a ratio of 1:6 and 925 parts of liquid B prepared with sodium metasilicate nonahydrate and water in a ratio of 1:3.5 were added dropwise for 4.5 hours. Add 5.5 parts of alkaline regulator triethanolamine for neutralization to obtain an early-strength concrete early-strength agent.

Example 3:

880 parts of water, 70 parts of diethylene glycol monobutyl ether, 40 parts of polyethylene glycol, and 10 parts of isopropanol were put into the reaction kettle, and stirred until completely dissolved; 935 parts of liquid A prepared by 1:4 of calcium nitrate tetrahydrate and water and 935 parts of liquid B prepared by 1:4.5 of sodium silicate and water were added dropwise for 5h, and 5.5 parts of alkaline regulator triethanolamine was added. Neutralization is carried out to obtain an early-strength concrete early-strength agent.

Example 4:

865 parts of water, 72 parts of diethylene glycol monobutyl ether, 44 parts of polyethylene glycol, and 15 parts of isopropanol were put into the reaction kettle, and stirred until completely dissolved; Equal weight parts of soluble calcium salts (calcium nitrate tetrahydrate and calcium formate, and the ratio of the two is 1:3) and water at 1:4.5 to prepare 950 parts of liquid A and soluble silicate (sodium metasilicate nonahydrate) and sodium silicate, and the ratio of the two is 1: 4) and 950 parts of liquid B prepared with water at 1: 3.8, added dropwise for 4.5h, and 5.2 parts of alkaline regulator triethanolamine was added for neutralization to obtain an ultra-early strength type Concrete early strength agent.

Example 5:

875 parts of water, 73 parts of diethylene glycol monobutyl ether, 42 parts of polyethylene glycol and 12 parts of isopropanol were put into the reaction kettle, stirred until completely dissolved; Equal weight parts of soluble calcium salts (calcium nitrate tetrahydrate and calcium formate, and the ratio of the two is 1:5) and 975 parts of liquid A prepared with water at 1:5.5 and B prepared with sodium silicate and water at 1:4.2 975 parts of liquid, added dropwise for 4.5h, and 5.4 parts of alkaline regulator triethanolamine was added for neutralization to obtain a super early-strength concrete early-strength agent.

Example 6:

875 parts of water, 71 parts of diethylene glycol monobutyl ether, 43 parts of polyethylene glycol, and 18 parts of isopropanol were put into the reaction kettle, and stirred until completely dissolved; 960 parts of liquid A prepared with equal parts by weight of calcium formate and water at 1:5.5 and soluble silicate (sodium metasilicate nonahydrate and sodium silicate, and the ratio of the two is 1:2) and water at 1:5. 4. 960 parts of the prepared liquid B was added dropwise for 4.3 hours, and 5.3 parts of an alkaline regulator triethanolamine was added for neutralization to obtain an early-strength concrete early-strength agent.

Example 7:

865 parts of water, 72 parts of diethylene glycol monobutyl ether, 45 parts of polyethylene glycol, and 15 parts of isopropanol were put into the reaction kettle, and stirred until they were completely dissolved; 945 parts of A solution prepared with equal weight of calcium nitrate tetrahydrate and water at 1:4.3 and 945 parts of B solution prepared by sodium metasilicate nonahydrate and water at 1:4.2, added dropwise for 4.3h, and an alkaline regulator was added. 5 parts of triethanolamine are neutralized to obtain an early-strength concrete early-strength agent.

Example 8:

877 parts of water, 71 parts of diethylene glycol monobutyl ether, 42 parts of polyethylene glycol, and 12 parts of isopropanol were put into the reaction kettle, and stirred until completely dissolved; Equal weight parts of soluble calcium salts (calcium nitrate tetrahydrate and calcium formate, and the ratio of the two is 1:6) and water at 1:4.6 to prepare 955 parts of liquid A and soluble silicate (sodium metasilicate nonahydrate) and sodium silicate, and the ratio of the two is 1: 5) and 955 parts of liquid B prepared with water at 1: 3.7, added dropwise for 4.7 h, and 5.1 parts of alkaline regulator triethanolamine was added for neutralization to obtain an ultra-early strength type Concrete early strength agent.

The super-early-strength concrete early-strength agent obtained in the above-mentioned Examples 1-8 was added to the ordinary C50 concrete in a proportion of 5.0% of the cementitious material. The test results of relevant performance indicators are shown in Table 1.

Table 1 Performance index test results of each embodiment

To sum up, the present invention has the following beneficial technical effects:

1. The present invention utilizes calcium salts and silicates to obtain nanoscale calcium silicate particles by adjusting the Ca/Si ratio and under the action of a dispersant, and this early strength agent provides a crystal nucleus class inducer in the initial stage of cement hydration, Reduce the nucleation barrier of cement hydration products, speed up the hydration process of hydration products, and then improve the early strength of cement-based materials, but will not cause later strength collapse.

2. The 8h compressive strength of concrete can reach more than 60% of the design strength by using the early strength agent provided by the present invention under normal temperature and pressure and humidity of 95%, shortening the demoulding time, speeding up the mold turnover rate, and the later strength will not occur. shrink back.

3. The preparation method of the present invention is simple and easy to operate, and only needs to add all the raw material components into the reaction kettle according to different orders, stir and disperse evenly, eliminate the steaming and autoclaving process in the prior art, and save energy and reduce consumption.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention are within the rights to be approved in the present invention. within the scope of protection.

Claims (5)

1. a super early-strength concrete early-strength agent is characterized in that, in parts by weight, the concrete early-strength agent comprises the following components: Water, 860-880 parts; Diethylene glycol monobutyl ether, 70-75 parts; Polyethylene glycol, 40-45 parts; Isopropanol, 10-20 parts; Soluble inorganic salt solution, 1850-1950 parts; Base Sexual modifier, 5-5.5 servings; The soluble inorganic salt solution is composed of liquid A and liquid B, and the weight ratio of liquid A: liquid B=1:1; Described A liquid is the soluble calcium salt solution that soluble calcium salt and water are prepared with the weight part ratio of 1: 4-6, and described soluble calcium salt is tetrahydrate calcium nitrate and calcium formate, and the ratio of the two is 1 :3-6; The B liquid is a soluble silicate solution prepared by soluble silicate and water in a weight ratio of 1:3.5-4.5, and the soluble silicate is sodium metasilicate nonahydrate and sodium silicate, And the ratio of the two is 1:2-5; The pH of the concrete early strength agent is 7-8; The concrete early-strength agent can make the concrete 8h compressive strength reach more than 60% of the design strength under the conditions of normal temperature and normal pressure and humidity of 95%. 2. The concrete early strength agent according to claim 1, characterized in that, the alkaline regulator is triethanolamine. 3. a preparation method of concrete early strength agent as claimed in claim 1 or 2, is characterized in that, described preparation method comprises the steps: 1) According to the proportioning design of the raw materials of each component, measure and take them for later use; 2) the water, diethylene glycol monobutyl ether, polyethylene glycol and isopropanol weighed in step 1) are put into the reactor, mixed and stirred until completely dissolved; 3) under normal temperature situation, in step 2) in the obtained solution, while stirring, continue to drip A liquid and B liquid that have prepared equal parts by weight respectively; 4) After the dropwise addition in step 3), an alkaline regulator is added to the mixed solution, and the stirring is continued for 0.2-1 h, and the mixed solution in the reaction kettle is neutralized to a pH of 7-8 to obtain an ultra-early-strength concrete. Strong agent. 4. The preparation method of concrete early strength agent according to claim 3, characterized in that, in step 3), the dropping rate of the A liquid and the B liquid is 1.5-2.0 kg/h. 5. The preparation method of concrete early strength agent as claimed in claim 3, is characterized in that, in step 4), continue to stir for 0.5h.