阅读说明：本技术 一种低吸水率轻骨料泡沫混凝土及其制备方法 (Low-water-absorption light aggregate foam concrete and preparation method thereof ) 是由 潘珑云 余小兰 明邦泉 赵国卫 钟佛明 于 2021-08-28 设计创作，主要内容包括：本发明涉及泡沫混凝土领域,具体公开了一种低吸水率轻骨料泡沫混凝土及其制备方法,低吸水率轻骨料泡沫混凝土,由混凝土拌和料制得,所述混凝土拌和料包括以下组分：水；水泥；粉状填料；发泡剂；氟硅酸钠；次亚磷酸钠。泡沫混凝土的制备方法,包括：步骤1),将水、发泡剂、氟硅酸钠、次亚磷酸钠混合,搅拌发泡,获得泡沫液；步骤2),在泡沫液中投入水泥,混合均匀获得泡沫水泥液；步骤3),在泡沫水泥液中加入粉状填料,混合均匀,获得混凝土拌和料；步骤4),将混凝土拌和料注入模具中,养护脱模得低吸水率轻骨料泡沫混凝土。本发明的泡沫混凝土具有增加使用范围的优点,本发明的制备方法具有制得的泡沫混凝土质量较佳的优点。(The invention relates to the field of foam concrete, and particularly discloses low-water-absorption light aggregate foam concrete and a preparation method thereof, wherein the low-water-absorption light aggregate foam concrete is prepared from concrete mixture, and the concrete mixture comprises the following components: water; cement; a powdery filler; a foaming agent; sodium fluosilicate; sodium hypophosphite. The preparation method of the foam concrete comprises the following steps: step 1), mixing water, a foaming agent, sodium fluosilicate and sodium hypophosphite, and stirring for foaming to obtain a foam liquid; step 2), adding cement into the foam liquid, and uniformly mixing to obtain foam cement liquid; step 3), adding powdery filler into the foam cement liquid, and uniformly mixing to obtain a concrete mixture; and 4), injecting the concrete mixture into a mould, and curing and demoulding to obtain the low-water-absorption light aggregate foam concrete. The foam concrete has the advantage of increasing the application range, and the preparation method has the advantage of better quality of the prepared foam concrete.)

1. A low water absorption light aggregate foam concrete is characterized in that: the concrete is prepared from concrete mixture, wherein the concrete mixture comprises the following components in parts by weight:

100 parts of water;

cement 158-;

112 portions of powdery filler 108;

1.95-2.05 parts of a foaming agent;

0.38-0.42 part of sodium fluosilicate;

1.18 to 1.22 portions of sodium hypophosphite.

2. The low water absorption lightweight aggregate foam concrete according to claim 1, wherein: the concrete mixture comprises the following components in parts by weight:

100 parts of water;

159 and 161 portions of cement;

109-111 portions of powdery filler;

1.98-2.02 parts of a foaming agent;

0.39-0.41 part of sodium fluosilicate;

1.19 to 1.21 portions of sodium hypophosphite.

3. A low water absorption lightweight aggregate foam concrete according to claim 2, characterized in that: the powdery filler is a compound of magnesium hydroxide, calcium carbonate, silica micropowder and feldspar powder.

4. A low water absorption lightweight aggregate foam concrete according to claim 3, characterized in that: the mass ratio of the magnesium hydroxide, the calcium carbonate, the silica micropowder and the feldspar powder is 1: 0.2: 0.8: 4.

5. a low water absorption lightweight aggregate foam concrete according to claim 2, characterized in that: the foaming agent is a compound of sodium dodecyl sulfate, fatty alcohol-polyoxyethylene ether sodium sulfate, triethanolamine and n-dodecanol.

6. The low water absorption lightweight aggregate foam concrete according to claim 5, wherein: the mass ratio of the lauryl sodium sulfate to the fatty alcohol-polyoxyethylene ether sodium sulfate to the triethanolamine to the n-dodecanol is 1: 0.8: 0.11: 0.09.

7. a method for the production of a low water absorption lightweight aggregate foam concrete according to any one of claims 1 to 6, characterized in that: the method comprises the following steps:

step 1), mixing water, a foaming agent, sodium fluosilicate and sodium hypophosphite, and stirring for foaming to obtain a foam liquid;

step 2), adding cement into the foam liquid, and uniformly mixing to obtain foam cement liquid;

step 3), adding powdery filler into the foam cement liquid, and uniformly mixing to obtain a concrete mixture;

and 4), injecting the concrete mixture into a mould, and curing and demoulding to obtain the low-water-absorption light aggregate foam concrete.

8. The method for preparing the low water absorption light aggregate foam concrete according to claim 7, wherein the method comprises the following steps:

in the step 1), the stirring speed is 600r/min or more when stirring and foaming.

Technical Field

The invention relates to the field of foam concrete, in particular to low-water-absorption light aggregate foam concrete and a preparation method thereof.

Background

The foam concrete is a light heat-insulating material containing large-lao closed air holes, has good performances of light weight, heat insulation, sound insulation and the like, is widely used in buildings, and the air holes in the foam concrete can be generated in a chemical foaming or physical foaming mode.

Because the foam concrete contains a large number of air holes, the foam concrete is no longer in a compact structure, so that the compressive strength of the foam concrete is reduced, the more the air holes are, the better the effects of reducing the weight, insulating heat and sound are, but the more the strength is reduced, the foam concrete needs to be balanced in strength and other properties, namely, in order to keep enough strength, partial heat insulation and sound insulation properties must be sacrificed, so that the application range of the foam concrete is limited, and therefore, the improvement space is provided.

Disclosure of Invention

In order to increase the application range of the foam concrete, the application provides the low-water-absorption light aggregate foam concrete and the preparation method thereof.

In a first aspect, the present application provides a low water absorption light aggregate foam concrete, which adopts the following technical scheme:

the low-water-absorption light aggregate foam concrete is prepared from a concrete mixture, wherein the concrete mixture comprises the following components in parts by weight:

100 parts of water;

cement 158-;

112 portions of powdery filler 108;

1.95-2.05 parts of a foaming agent;

0.38-0.42 part of sodium fluosilicate;

1.18 to 1.22 portions of sodium hypophosphite.

Preferably, the concrete mixture comprises the following components in parts by weight:

100 parts of water;

159 and 161 portions of cement;

109-111 portions of powdery filler;

1.98-2.02 parts of a foaming agent;

0.39-0.41 part of sodium fluosilicate;

1.19 to 1.21 portions of sodium hypophosphite.

Through adopting above-mentioned technical scheme, through adding sodium fluorosilicate, sodium hypophosphite for foam concrete's compressive strength can promote, thereby can keep more gas pockets under the same intensity level, makes thermal-insulated, the effect that gives sound insulation better, also can be under the same thermal-insulated, the level that gives sound insulation, has higher compressive strength in order to accord with the engineering needs, makes foam concrete's application range wider.

In view of the above, the inventors speculate that the addition of sodium fluorosilicate and sodium hypophosphite can generate fluorosilicate ions and hypophosphite ions in concrete mixture, when fluorosilicate ions and hypophosphite ions exist in a specific ratio, the hydrated calcium silicate colloid can cause the existence of impurities, namely fluorosilicate ions and hypophosphite ions, to cause the change of partial crystal forms during crystallization, generally, crystals formed by the hydrated calcium silicate colloid mainly have needle-like and prism-like crystal forms, when fluorosilicate ions and hypophosphite ions are added, the hydrated calcium silicate colloid can generate partial needle-like crystal forms, while the needle-like and prism-like crystal forms still remain, which can make the needle-like and prism-like crystal forms, especially the needle-like crystal forms, penetrate into pores of the snow-like crystal forms, thereby forming a more complex crystal structure with stronger mutual restriction ability, therefore, after the calcium silicate hydrate colloid is bonded with the powdery filler, the bonding force is larger, the set cement is not easy to break, and the strength is higher, so that the performance improvement of the strengthening of the compressive strength of the solid part of the concrete is realized macroscopically, the compressive strength of the whole foam concrete is improved under the same air hole level, and the number of air holes in the foam concrete can be increased under the same compressive strength condition.

By adding the powdery filler, the capillary pores of the solid part of the foam concrete are effectively filled while providing the pressure resistance for the foam concrete, so that the solid part of the foam concrete is more compact, the impermeability is stronger, and the water absorption of the foam concrete is lower.

Preferably, the powdery filler is a compound of magnesium hydroxide, calcium carbonate, silica micropowder and feldspar powder.

By adopting the technical scheme, the powdery filler is formed by compounding the magnesium hydroxide, the calcium carbonate, the silica micropowder and the feldspar powder, so that the effect of filling pores of the foam concrete is better, and the effect of improving the compressive strength of the foam concrete is better.

Preferably, the mass ratio of the magnesium hydroxide, the calcium carbonate, the silica micropowder and the feldspar powder is 1: 0.2: 0.8: 4.

by adopting the technical scheme, the effect of reducing the water absorption of the foam concrete is better and the effect of improving the compressive strength of the foam concrete is better by matching the magnesium hydroxide, the calcium carbonate, the silica powder and the feldspar powder in a specific proportion.

Preferably, the foaming agent is a compound of sodium dodecyl sulfate, fatty alcohol-polyoxyethylene ether sodium sulfate, triethanolamine and n-dodecanol.

By adopting the technical scheme, the formed foam interface has better flexibility, the foam is not easy to break, the number of formed air holes is more and stable, the occurrence of through holes is reduced, more closed air holes of the foam concrete are formed, and the water absorption rate is reduced by matching the lauryl sodium sulfate, the fatty alcohol-polyoxyethylene ether sodium sulfate, the triethanolamine and the n-dodecanol.

Preferably, the mass ratio of the lauryl sodium sulfate, the fatty alcohol-polyoxyethylene ether sodium sulfate, the triethanolamine and the n-dodecanol is 1: 0.8: 0.11: 0.09.

by adopting the technical scheme, the foam stability is stronger, the effect of reducing the water absorption rate of the foam concrete is better and the quality of the foam concrete is better by matching the lauryl sodium sulfate, the fatty alcohol-polyoxyethylene ether sodium sulfate, the triethanolamine and the n-dodecanol in a specific ratio.

In a second aspect, the present application provides a method for preparing a low water absorption light aggregate foam concrete, which adopts the following technical scheme:

the preparation method of the low-water-absorption light aggregate foam concrete comprises the following steps:

step 1), mixing water, a foaming agent, sodium fluosilicate and sodium hypophosphite, and stirring for foaming to obtain a foam liquid;

step 2), adding cement into the foam liquid, and uniformly mixing to obtain foam cement liquid;

step 3), adding powdery filler into the foam cement liquid, and uniformly mixing to obtain a concrete mixture;

and 4), injecting the concrete mixture into a mould, and curing and demoulding to obtain the low-water-absorption light aggregate foam concrete.

By adopting the technical scheme, the water, the foaming agent, the sodium fluosilicate and the sodium hypophosphite are mixed firstly, so that fluosilicic acid radical ions and hypophosphite radical ions are uniformly dispersed in the foaming process, and are uniformly distributed in the cement foam liquid after the cement is added, the cement modification effect is more uniform and effective, and the prepared foam concrete has better quality.

Preferably, in the step 1), the stirring rotation speed is 600r/min or more during stirring foaming.

Through adopting above-mentioned technical scheme, stir the foaming through 600r/min and above rotational speed for the foaming effect is better, fully stirs the air into in the liquid in order to form the foam, and make full use of foaming is crowded, makes and promotes with the sensitivity of adjusting gas pocket quantity through adjusting the foamer quantity, in order to realize adjusting the structure of foam concrete better, makes the foam concrete quality of making more stable.

In summary, the present application has the following beneficial effects:

1. because this application is through adding sodium fluorosilicate, sodium hypophosphite for the compressive strength of foam concrete can promote, thereby can keep more gas pockets under the same intensity level, make thermal-insulated, the effect that gives sound insulation better, also can be under the same thermal-insulated, the level that gives sound insulation, have higher compressive strength in order to accord with the engineering needs, make the application range of foam concrete wider.

2. In the application, the magnesium hydroxide, the calcium carbonate, the silica micropowder and the feldspar powder are preferably mixed in a specific ratio, so that the effect of reducing the water absorption of the foam concrete is better, and the effect of improving the compressive strength of the foam concrete is better.

3. According to the foam concrete, the lauryl sodium sulfate, the fatty alcohol-polyoxyethylene ether sodium sulfate, the triethanolamine and the n-dodecanol are preferably matched in a specific proportion, so that the foam stability is higher, the effect of reducing the water absorption of the foam concrete is better, and the quality of the foam concrete is better.

4. According to the method, water, the foaming agent, the sodium fluosilicate and the sodium hypophosphite are mixed firstly, so that fluosilicic acid radical ions and hypophosphite radical ions are uniformly dispersed in the foaming process, and are uniformly distributed in the cement foam liquid after the cement is added, the cement modification effect is more uniform and effective, and the prepared foam concrete has better quality.

Detailed Description

The present application will be described in further detail with reference to examples.

The information on the source of the raw materials used in the following examples and comparative examples is detailed in Table 1.

TABLE 1

Examples 1 to 5

A low-water absorption light aggregate foam concrete comprises the following components:

water, cement, powdery filler, foaming agent, sodium fluosilicate and sodium hypophosphite.

Wherein the powdery filler is prepared from magnesium hydroxide, calcium carbonate, silica micropowder and feldspar powder in a mass ratio of 1: 0.2: 0.8: 4 are compounded.

Wherein the foaming agent is prepared from sodium dodecyl sulfate, fatty alcohol-polyoxyethylene ether sodium sulfate, triethanolamine and n-dodecanol according to the mass ratio of 1: 0.8: 0.11: 0.09, and the like.

In examples 1 to 5, the specific amounts of the respective components to be charged are shown in Table 2.

TABLE 2

In examples 1 to 5, the preparation method of the low water absorption lightweight aggregate foam concrete comprises the following steps:

step 1), putting water, a foaming agent, sodium fluosilicate and sodium hypophosphite into a stirring kettle, keeping the liquid level of a stirring blade at the top part not higher than that of the stirring blade at the top part, keeping the part of the stirring blade at the top part below the liquid level and the part above the liquid level, stirring at the rotating speed of 600r/min for 10min, and stirring and foaming to obtain a foam liquid;

step 2), putting cement into the foam liquid, stirring for 8min at the rotating speed of 200r/min, and uniformly mixing to obtain foam cement liquid;

step 3), adding powdery filler into the foam cement liquid, stirring for 15min at the rotating speed of 60r/min, and uniformly mixing to obtain a concrete mixture;

and 4), injecting the concrete mixture into a mould, naturally curing for 7d, demoulding, and naturally curing to 28d to obtain the low-water-absorption light aggregate foam concrete.

Comparative example 1

A low water absorption light aggregate foam concrete is different from the foam concrete of example 5 only in that:

the specific input amount of the sodium fluosilicate is 1 kg.

The specific amount of sodium hypophosphite added was 0.5 kg.

Comparative example 2

A low water absorption light aggregate foam concrete is different from the foam concrete of example 5 only in that:

the specific input amount of the sodium fluosilicate is 0.1 kg.

The specific amount of sodium hypophosphite added was 1.5 kg.

Comparative example 3

A low water absorption light aggregate foam concrete is different from the foam concrete of example 5 only in that:

the powdery filler is used to replace sodium hypophosphite in equal amount.

Comparative example 4

A low water absorption light aggregate foam concrete is different from the foam concrete of example 5 only in that:

the powdery filler is used to replace sodium fluosilicate in equal amount.

Comparative example 5

A low water absorption light aggregate foam concrete is different from the foam concrete of example 5 only in that:

the powdery filler is used to replace sodium fluosilicate and sodium hypophosphite in equal amount.

Experiment 1

The samples prepared from the concrete mixture of each example and each comparative example were tested for compressive strength, dry density, water absorption, and thermal conductivity according to JG/T266-2011 foam concrete.

The assay data for experiment 1 is detailed in table 3.

TABLE 3

According to the comparison of the data of the example 5 and the comparative examples 1 to 5 in the table 3, when the sodium fluorosilicate or the sodium hypophosphite is added into the concrete mixture alone, the compressive strength of the prepared sample is not obviously improved, when the sodium fluorosilicate and the sodium hypophosphite are added into the concrete mixture at the same time but are not mixed in a specific ratio, the compressive strength of the prepared sample is improved to a certain extent, but the improvement is not large, when the sodium fluorosilicate and the sodium hypophosphite are mixed in a specific ratio, the compressive strength of the prepared sample is greatly improved, so that the compressive strength of the prepared foam concrete is higher, and under the level of the same number of air holes, the foam concrete can bear more pressure to meet the requirements of more severe engineering.

According to the comparison of the data of examples 1-5 in Table 3, the prepared samples have lower density, water absorption and thermal conductivity, and the results show that the prepared foam concrete has light weight, more pores, low water absorption, stronger impermeability and lower thermal conductivity, so that the prepared foam concrete has stronger heat insulation capability and better quality, and when the sodium fluosilicate and the sodium hypophosphite are matched according to the specific proportion of example 5, the prepared foam concrete has the best performance.

The present embodiment is only for explaining the present application, and it is not limited to the present application, and those skilled in the art can make modifications of the present embodiment without inventive contribution as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present application.