阅读说明：本技术 一种内掺型混凝土增强剂及其制备方法 (Internal-doped concrete reinforcing agent and preparation method thereof ) 是由 李玉凤 黄玉美 刘磊 刘欢 王龙 李茜茜 刘翠芬 于 2021-03-23 设计创作，主要内容包括：本发明涉及混凝土添加剂领域,公开了一种内掺型混凝土增强剂及其制备方法,按照质量份数包括以下原料组分：去离子水80～90份,碳酸钾0.2～1.0份,丙烯酸钙2～5份,混合小料2～5份,消泡剂0.01～0.05份；其中混合小料为小分子醇胺类物质、三乙醇胺、二乙醇单异丙醇胺和三异丙醇胺四种按任意比例形成的混合物。本发明通过各组分的协同作用,与外加剂配合使用可显著改善混凝土的拌合物和易性,并能促进胶凝材料的充分水化,全面提高混凝土各龄期的强度；而且还能降低水泥石的孔隙率优化孔隙分布,提高致密性,从而提高了混凝土的抗蚀性能。(The invention relates to the field of concrete additives, and discloses an internal-doped concrete reinforcing agent and a preparation method thereof, wherein the internal-doped concrete reinforcing agent comprises the following raw material components in parts by mass: 80-90 parts of deionized water, 0.2-1.0 part of potassium carbonate, 2-5 parts of calcium acrylate, 2-5 parts of mixed small materials and 0.01-0.05 part of defoaming agent; wherein the mixed small materials are a mixture of micromolecular alcamines, triethanolamine, diethanol monoisopropanolamine and triisopropanolamine according to any proportion. The invention can obviously improve the mixture workability of the concrete by the synergistic effect of all the components and the matching use of the admixture, can promote the full hydration of the cementing material and comprehensively improve the strength of the concrete at each age; but also can reduce the porosity of the set cement, optimize the pore distribution and improve the compactness, thereby improving the corrosion resistance of the concrete.)

1. The internal-doped concrete reinforcing agent is characterized by comprising the following raw material components in parts by weight: 80-90 parts of deionized water, 0.2-1.0 part of potassium carbonate, 2-5 parts of calcium acrylate, 2-5 parts of mixed small materials and 0.01-0.05 part of defoaming agent; wherein the mixed small materials are a mixture of micromolecular alcamines, triethanolamine, diethanol monoisopropanolamine and triisopropanolamine according to any proportion.

2. The incorporative concrete enhancer of claim 1, wherein: the mass ratio of the small molecular alkanolamines, the triethanolamine, the diethanol monoisopropanolamine and the triisopropanolamine in the small mixed material is (0.6-1.5): (2.0-2.8): (2.0-2.8): (1.0-2.5).

3. The incorporative concrete enhancer of claim 1, wherein: the small molecular alcohol amine substance is any one or more of monoethanolamine, monoisopropanolamine and diethanolamine.

4. The incorporative concrete enhancer of claim 1, wherein: and also comprises 0.2-0.5 part of calcium formate.

5. The incorporative concrete enhancer of claim 1, wherein: also comprises 2.5 to 3.8 parts of ethylene glycol and 2.5 to 3.8 parts of 1, 2-propylene glycol.

6. A method for preparing an internal-doped concrete reinforcing agent, which is used for preparing the internal-doped concrete reinforcing agent in claim 1 or 2, and is characterized by comprising the following process steps:

s1, adding deionized water, potassium carbonate and calcium acrylate into a compounding kettle according to the using amount ratio at the temperature of 20 ℃, and stirring for 5-15 min to obtain a uniform solution;

and S2, adding a small mixed material consisting of micromolecular alcamines, triethanolamine, diethanol monoisopropanolamine and triisopropanolamine into the compounding kettle, and stirring for 15-45 min to obtain the concrete reinforcing agent.

7. The method for preparing the internal-doped concrete reinforcing agent according to claim 5, wherein the method comprises the following steps: in step S1, 0.2-0.5 parts of calcium formate is also added.

8. The incorporative concrete enhancer of claim 5, wherein: in the step S2, 2.5-3.8 parts of ethylene glycol and 2.5-3.8 parts of 1, 2-propylene glycol are also added.

Technical Field

The invention relates to the field of composite fiber materials, in particular to an internal-doped concrete reinforcing agent and a preparation method thereof.

Background

The concrete is an engineering composite artificial stone which is formed by binding aggregate into a whole by a binding material, has low manufacturing cost, is a preferred material in civil engineering structures, and is one of the most common structural forms at present. With the continuous progress of science and technology, particularly the use of the admixture, the performance of the concrete is obviously improved, and the cost is obviously reduced. In order to ensure the workability of concrete, about 20% of cement in concrete is not sufficiently hydrated by the effect of the conventional admixture, and thus the strength of concrete cannot be further improved. In addition, with the rapid development of the building industry and the public road bridge industry and the continuous improvement of the design level, in order to meet the requirement of accelerating the completion of various project periods in advance, the low-temperature construction conditions of cement concrete in winter in off seasons and winter in winter exist in large quantity.

In view of such current situation, experts and scholars in various countries have made a lot of scientific researches on concrete reinforcing agents, but have not made obvious progress all the time. From the large number of documents published at present, the following drawbacks are mainly present:

1) the existing reinforcing agent products aim at more pure cement production process, and the reinforcing agent products specially aiming at concrete are relatively less, however, the difference between the material components and the performance of the cement and the concrete is larger, if the cement reinforcing agent is directly carried in the concrete, the effect is often greatly changed, and the expected reinforcing purpose is difficult to achieve;

2) the adaptability of the existing concrete reinforcing agent and the admixture used for the existing concrete production is not strong, and the existing reinforcing agent is suitable for a naphthalene water reducing agent, but has almost no effect on polycarboxylic acid and aliphatic water reducing agent;

3) the existing partial concrete reinforcing agent products are difficult to prepare and high in cost, and the improvement on the concrete performance needs to be further improved.

Therefore, how to improve the formula, raw materials and preparation process of the existing concrete reinforcing agent is a long-standing technical problem for those skilled in the art.

Disclosure of Invention

Based on the problems, the invention provides the internal-doped concrete reinforcing agent and the preparation method thereof, through the synergistic effect of the components, the mixture workability of the concrete can be obviously improved by matching with the additive, the full hydration of the cementing material can be promoted, and the strength of the concrete at each age can be comprehensively improved; but also can reduce the porosity of the set cement, optimize the pore distribution and improve the compactness, thereby improving the corrosion resistance of the concrete.

In order to realize the technical effect, the invention adopts the following technical scheme:

the internal-doped concrete reinforcing agent comprises the following raw material components in parts by weight: 80-90 parts of deionized water, 0.2-1.0 part of potassium carbonate, 2-5 parts of calcium acrylate, 2-5 parts of mixed small materials and 0.01-0.05 part of defoaming agent; wherein the mixed small materials are a mixture of micromolecular alcamines, triethanolamine, diethanol monoisopropanolamine and triisopropanolamine according to any proportion.

Furthermore, the mass ratio of the small molecular alcohol amine substances, the triethanolamine, the diethanol monoisopropanolamine and the triisopropanolamine in the small mixed materials is (0.6-1.5): (2.0-2.8): (2.0-2.8): (1.0-2.5).

Further, the small molecular alcohol amine substance is any one or more of monoethanolamine, monoisopropanolamine and diethanolamine.

Further, the paint also comprises 0.2-0.5 parts of calcium formate.

Further, the paint also comprises 2.5-3.8 parts of ethylene glycol and 2.5-3.8 parts of 1, 2-propylene glycol.

In order to realize the technical effects, the invention also provides a preparation method of the internal-doped concrete reinforcing agent, which comprises the following process steps:

s1, adding deionized water, potassium carbonate and calcium acrylate into a compounding kettle according to the using amount ratio at the temperature of 20 ℃, and stirring for 5-15 min to obtain a uniform solution;

and S2, adding a small mixed material consisting of micromolecular alcamines, triethanolamine, diethanol monoisopropanolamine and triisopropanolamine into the compounding kettle, and stirring for 15-45 min to obtain the concrete reinforcing agent.

Further, 0.2-0.5 parts of calcium formate is added in step S1.

Further, 2.5 to 3.8 parts of ethylene glycol and 2.5 to 3.8 parts of 1, 2-propylene glycol are added in the step S2.

Compared with the prior art, the invention has the beneficial effects that: according to the invention, through the synergistic effect of the components, the workability of the mixture of the concrete can be obviously improved by matching with the additive, the full hydration of the cementing material can be promoted, and the strength of the concrete at each age can be comprehensively improved; but also can reduce the porosity of the set cement, optimize the pore distribution and improve the compactness, thereby improving the corrosion resistance of the concrete.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following examples, and the exemplary embodiments and descriptions thereof are only used for explaining the present invention and are not to be construed as limiting the present invention.

Example 1:

the internal-doped concrete reinforcing agent comprises the following raw material components in parts by weight: 80-90 parts of deionized water, 0.2-1.0 part of potassium carbonate, 2-5 parts of calcium acrylate, 2-5 parts of mixed small materials and 0.01-0.05 part of defoaming agent; wherein the mixed small materials are a mixture of micromolecular alcamines, triethanolamine, diethanol monoisopropanolamine and triisopropanolamine according to any proportion. The small molecular alcohol amine substance can be any one or more of monoethanolamine, monoisopropanolamine and diethanolamine.

In the embodiment, the calcium acrylate can have good interface combination with cement, and the addition of the calcium acrylate can reduce the porosity of set cement, optimize the pore distribution and improve the corrosion resistance of the cement. The calcium acrylate forms a network structure in the set cement, penetrates through the set cement and can form good interface bonding with the cement. Can fill the holes of the set cement and improve the compactness.

The potassium carbonate in the embodiment can accelerate the coagulation speed of colloid formed by substances such as cement, water and the like, and can react with hydration product calcium hydroxide of the cement as follows:

K₂CO₃+Ca(OH)₂＝CaCO₃↓+2KOH

wherein CaCO₃The calcium aluminate cement slurry is not inert substances in the hardened cement slurry and can further react with hydration products containing aluminum phases in the cement to generate high-strength calcium carbonate aluminate; can also act on hydration products of silicate phases, CaCO₃The early hydration of C3S is accelerated, the early strength development of concrete is facilitated, and the concrete has a certain anti-freezing effect. And in CaCO₃And the interfacial region of the C3S slurry is near the CaCO₃A new product, namely basic calcium carbonate, appears on one side of the surface, and the existence of the new phase is beneficial to the improvement of the structure of an interface area and the enhancement of the bonding force and is finally beneficial to the improvement of the mechanical property of hardened cement paste.

The mixed small materials in the embodiment are a mixture composed of various kinds of alcohol amine substances such as small molecular alcohol amine substances, triethanolamine, diethanol monoisopropanolamine, triisopropanolamine and the like according to a certain proportion, and can be used for further improving the strength of concrete at each age. Their mechanism of action is as follows:

a triethanolamine: can react with Al in high alkaline solution³⁺And Fe³⁺Combining to form a soluble complex, thereby promoting initial hydration of the aluminate phase in the cement and accelerating the reaction between the gypsum and the aluminate; meanwhile, the complexation reaction of triethanolamine reduces Ca in liquid phase²⁺、Al³⁺The concentration of the (B) is favorable for the development of early strength of cement by further promoting the hydration of C3S, accelerating the formation of ettringite, accelerating the setting of cement slurry and simultaneously inhibiting the hydration of C3S and beta-C2S. However, the adsorption of triethanolamine affects the full exploitation of the beneficial effects: when the silicate in the cement is hydrated to form CH, triethanolamine is adsorbed to the surface of the crystal to prevent the complexation reaction of the triethanolamine. This makes triethanolamine impossible to exhibit a later reinforcing effect on cement. Therefore, triethanolamine can only improve early strength and has no effect on later strength.

② triisopropanolAmine: has the advantages of strong self-dispersibility and difficult adsorption to the crystal or particle surface, thus not promoting the hydration of cement minerals and not improving the early strength. However, triisopropanolamine can react mainly with Fe³⁺Complexing and promoting the hydration of C4AF, specifically: c4AF hydration generates a certain amount of iron ions (including similar aluminum ions) and continues to form ferric hydroxide gel which covers the surface of the hydrated mineral to further level the hydration; when triisopropanolamine exists, the generated iron ions and triisopropanolamine can form a complex which is easy to dissolve in water under the condition of high pH, so that the phenomenon that the iron ions are enriched to generate gel to cover the surface of a reactant to delay hydration is avoided, and the triisopropanolamine promotes the speed of converting ettringite to low-sulfur calcium aluminate, thereby improving the later hydration strength of cement. However, if the amount of triisopropanolamine is increased, the strength tends to be reduced.

③ diethanolisopropanolamine: the early strength and the later strength are obviously improved, and the concrete early-strength and later-strength concrete is mainly used for further enhancing the early strength and the later strength of concrete so as to solve the problem that triethanolamine and triisopropanolamine cannot be added. However, in general, the early strength is lower than triethanolamine and the late strength is lower than triisopropanolamine. The diethanol monoisopropanolamine has good compatibility with triethanolamine, triisopropanolamine and other alcohols, amines and lipids. According to the characteristics of different cement materials, diethanol monoisopropanolamine is used as a core raw material, and after targeted compatibility, the early strength and the later strength of the cement are remarkably improved.

Since the three small materials respectively have the promotion effect on the hydration of the cement in different periods, if the three small materials are simply mixed physically, the three small materials cannot act simultaneously and can inhibit each other. In order to solve the problem, the embodiment adds small molecular alcohol amine substances.

Fourthly, micromolecular alcohol amine substances: the penetration force of the cement particle hydration film is very strong, the fracture of the hydration film on the surface of the cement particle can be accelerated, the hydration process of the cement can be accelerated, and more importantly, the cement particle hydration film can be prevented from wrapping so as not to participate in hydration. Therefore, the three types of alcohol amine substances can be promoted to fully play a role, so that the strength of the concrete at each age is increased.

The preparation process of the internal-doped concrete reinforcing agent in the embodiment is as follows:

s1, adding deionized water, potassium carbonate and calcium acrylate into a compounding kettle according to the using amount ratio at the temperature of 20 ℃, and stirring for 5-15 min to obtain a uniform solution;

and S2, adding a small mixed material consisting of micromolecular alcamines, triethanolamine, diethanol monoisopropanolamine and triisopropanolamine into the compounding kettle, and stirring for 15-45 min to obtain the concrete reinforcing agent.

Example 2:

an internal-doped concrete reinforcing agent comprises the following components in parts by weight: 0.5 part of potassium carbonate, 3 parts of calcium acrylate, 3.0 parts of small mixed materials, 0.03 part of defoaming agent and 86.97 parts of deionized water. Wherein the small mixed material is a mixture of diethanolamine, triethanolamine, diethanol monoisopropanolamine and triisopropanolamine according to the ratio of 0.8:2.5:2.5: 1.5. The preparation process comprises the steps of firstly adding deionized water, potassium carbonate and calcium acrylate into a compounding kettle according to the dosage ratio at the temperature of 20 ℃, and stirring for 5-15 min to obtain a uniform solution; and then adding a small mixed material consisting of micromolecular alcamines, triethanolamine, diethanol monoisopropanolamine and triisopropanolamine into the compounding kettle, and stirring for 15-45 min to obtain the concrete reinforcing agent.

The concrete mixing proportion is as follows: 280E win cement, 80 national standard secondary fly ash, 865 machine-made sand, 1072 stone and 170 water.

The mixing amount of the concrete reinforcing agent in the concrete is 7.5kg/m³Concrete and equivalent replacement of water use.

Experiments are carried out according to the mixture ratio, and the compressive strength ratio of the concrete test block doped with the concrete reinforcing agent is measured, and the results are shown in table 1.

Table 1 test results of concrete test block in example 2

Example 3:

a preparation method of an internal-doped concrete reinforcing agent comprises the following components in percentage by mass: 0.8 part of potassium carbonate, 3 parts of calcium acrylate, 3.0 parts of ethylene glycol, 3.3 parts of 1, 2-propylene glycol, 3.4 parts of small mixed materials, 0.04 part of defoaming agent and 86.46 parts of deionized water. Wherein the small mixed material is a mixture of monoethanolamine, triethanolamine, diethanol monoisopropanolamine and triisopropanolamine according to the ratio of 1.0:2.6:2.6: 1.8.

The concrete mixing proportion is as follows: 280E win cement, 80 national standard secondary fly ash, 865 machine-made sand, 1072 stone and 170 water.

The mixing amount of the concrete reinforcing agent in the concrete is 7.5kg/m³Concrete and equivalent replacement of water use.

Experiments are carried out according to the mixture ratio, and the compressive strength ratio of the concrete test block doped with the concrete reinforcing agent is measured, and the results are shown in table 2.

Table 2 test results of concrete test block in example 3

Example 4:

an internal-doped concrete reinforcing agent comprises the following components in parts by weight: 1.0 part of potassium carbonate, 0.3 part of calcium formate, 3 parts of calcium acrylate, 3.5 parts of ethylene glycol, 3.5 parts of 1, 2-propylene glycol, 4.0 parts of mixed small materials, 0.05 part of defoaming agent and 84.65 parts of deionized water. Wherein the small mixed material is a mixture of monoisopropanolamine, triethanolamine, diethanol monoisopropanolamine and triisopropanolamine according to the ratio of 1.2:2.6:2.6: 2.0. The preparation process comprises the steps of adding deionized water, potassium carbonate, calcium formate and calcium acrylate into a compound kettle at 20 ℃, stirring for 5-15 min to obtain a uniform solution, adding ethylene glycol, 1, 2-propylene glycol and mixed small materials into the compound kettle, and stirring for 15-45 min to obtain the concrete reinforcing agent.

The concrete mixing proportion is as follows: 280E win cement, 80 national standard secondary fly ash, 865 machine-made sand, 1072 stone and 170 water.

Concrete reinforcing agent is as followsThe mixing amount in the concrete is 7.5kg/m³Concrete and equivalent replacement of water use.

Experiments are carried out according to the mixture ratio, and the compressive strength ratio of the concrete test block doped with the concrete reinforcing agent is measured, and the results are shown in table 3.

Table 3 test results of concrete test block in example 4

In the embodiment, the freezing points of the 1, 2-propylene glycol and the ethylene glycol are lower, and the two substances and the liquid phase form a eutectic solution, so that the freezing point of the solution is greatly reduced, and the effect of reducing the freezing point is achieved. Therefore, the concrete has good frost resistance. The ethylene glycol is superior to the 1, 2-propylene glycol in terms of freezing resistance, but in consideration of toxicity, the 1, 2-propylene glycol belongs to a low-toxicity or non-toxic product, the ethylene glycol has higher toxicity and is more harmful to human bodies, and the price of the 1, 2-propylene glycol is higher than that of the ethylene glycol, so that the two are safer and more practical to use in combination. The calcium formate can adjust the coagulation and hardening speed of concrete, and can further shorten the demolding and curing time and accelerate the construction progress by adding the calcium formate in winter construction or concrete engineering with early strength requirements, thereby effectively improving the construction quality and saving the construction cost of concrete.

As can be seen from the above examples 2-4, the indexes of the concrete test block prepared from the concrete reinforcing agent of the invention are far higher than the index requirements.

In conclusion, the internal-doped concrete reinforcing agent can replace water to be mixed in concrete, can obviously improve the frost resistance, the gel material dispersibility and the compressive strength performance of the concrete, and is widely applied to the fields of civil engineering, hydraulic engineering, underground engineering, roads, bridges and other engineering.

The above is an embodiment of the present invention. The embodiments and specific parameters in the embodiments are only for the purpose of clearly illustrating the process of verifying the invention and are not intended to limit the scope of the invention, which is defined by the claims, and all the equivalent structural changes made by applying the content of the specification of the invention should be covered by the scope of the invention.