阅读说明：本技术 一种温控型混凝土膨胀剂 (Temperature control type concrete expanding agent ) 是由 辜振睿 王海龙 杨泽波 王德民 方博 纪宪坤 于 2020-07-27 设计创作，主要内容包括：本发明公开一种温控型混凝土膨胀剂,包括膨胀密实组分和温控组分；膨胀密实组分由水化调控型氧化钙-硫铝酸钙膨胀熟料、石膏、硅灰组成；所述的水化调控型氧化钙-硫铝酸钙膨胀熟料的生料由石灰石、石膏、铁渣、矾土,以及非金属氧化物或非金属氧化物和金属氧化物的复合物组成；温控组分包括抑制组分和调节组分,两者协同作用调节水泥净浆、混凝土的内部水化热、温峰和温峰出现的时间。本发明提供的膨胀剂,不仅在常温下,还能在40～60℃下对膨胀反应速率进行合理调控,降低、延缓水泥基材料的水化反应速率,降低混凝土构筑物因温度应力过大的开裂现象。(The invention discloses a temperature control type concrete expanding agent, which comprises an expanded compact component and a temperature control component; the expansion compacting component consists of hydration regulation type calcium oxide-calcium sulphoaluminate expansion clinker, gypsum and silica fume; the raw material of the hydration regulation type calcium oxide-calcium sulphoaluminate expansion clinker consists of limestone, gypsum, iron slag, alumina and a compound of a non-metal oxide or a non-metal oxide and a metal oxide; the temperature control component comprises an inhibiting component and an adjusting component, and the inhibiting component and the adjusting component cooperate to adjust the internal hydration heat, the temperature peak and the time of the temperature peak of the cement paste and the concrete. The expanding agent provided by the invention can reasonably regulate and control the expansion reaction rate at normal temperature and 40-60 ℃, reduce and delay the hydration reaction rate of a cement-based material, and reduce the cracking phenomenon of a concrete structure due to overlarge temperature stress.)

1. The temperature control type concrete expanding agent is characterized by comprising 90-99 wt% of an expanded compact component and 1-10 wt% of a temperature control component;

the expansion dense component comprises 55-92 wt% of hydration regulation type calcium oxide-calcium sulphoaluminate expansion clinker, 5-30 wt% of gypsum and 3-15 wt% of silica fume;

the temperature control component comprises 2-80 wt% of an inhibition component I, 5-50 wt% of an inhibition component II, 10-50 wt% of an inhibition component III, 1-50 wt% of an adjustment component I and 1-10 wt% of an adjustment component II;

the inhibiting component I is a hydroxypropyl compound with the intramolecular hydroxypropyl number not less than 1 and the ester group 0;

the inhibiting component II is a hydroxypropyl ester compound with the intramolecular hydroxypropyl number not less than 1 and the ester group not less than 1;

the inhibiting component III is a polyhydric alcohol compound which has more than or equal to 2 intramolecular hydroxyl groups and does not contain hydroxypropyl;

the specific surface area of the regulating component I is more than or equal to 500m²/kg of superfine mineral powder;

the adjusting component II is a retarder.

2. The temperature-controlled concrete expanding agent as claimed in claim 1, wherein the temperature-controlled component comprises 45 wt% of inhibiting component I, 20 wt% of inhibiting component II, 20 wt% of inhibiting component III, 10 wt% of regulating component I and 5 wt% of regulating component II.

3. The temperature-controlled concrete expansive agent according to claim 1 or 2, wherein the inhibiting component I is at least one of hydroxypropyl cellulose, hydroxypropyl starch, hydroxypropyl guar gum, hydroxypropyl-beta-cyclodextrin and hydroxypropyl methyl cellulose; the inhibiting component II is at least one of hydroxypropyl distarch phosphate and hydroxypropyl acrylate; the inhibiting component III is at least one of glucose, fructose, mannitol, glycerol, erythritol, xylitol, galactitol and sorbitol;

the regulating component I is superfine mineral powder with the specific surface area of more than or equal to 500 square meters per kg; the adjusting component II is at least one of sodium gluconate, sodium tripolyphosphate, sodium polyphosphate, sodium hexametaphosphate and sodium pyrophosphate.

4. The temperature-controlled concrete expanding agent according to claim 1, wherein the raw material mixture ratio of the hydration-controlled calcium oxide-calcium sulfoaluminate expanded clinker before firing comprises the following raw materials with specific surface area of more than or equal to 350 square meters per kilogram: 65-80 wt% of limestone, 5-15 wt% of gypsum, 2-5 wt% of iron slag, 6-15 wt% of alumina, and 7-20 wt% of a non-metal oxide or a composite of a non-metal oxide and a metal oxide.

5. The temperature-control concrete expanding agent according to claim 4, wherein the raw material mixture ratio of the hydration-control calcium oxide-calcium sulfoaluminate expanded clinker before firing comprises the following raw materials with specific surface area of more than or equal to 350 square meters per kilogram: 70 wt% of limestone, 7 wt% of gypsum, 3 wt% of iron slag, 9 wt% of alumina and 11 wt% of non-metal oxide or composite of non-metal oxide and metal oxide.

6. The temperature-controlled concrete expansive agent according to claim 4 or 5, wherein the non-metal oxide comprises at least one of P, Si oxide, and the metal oxide comprises at least one of Mg, Zn, Fe, Cu oxide.

7. The temperature-controlled concrete expanding agent according to claim 4 or 5, wherein the preparation method of the hydration-controlled calcium oxide-calcium sulfoaluminate expanded clinker comprises the following steps:

s1, mixing all the raw meal powder uniformly, and adding water to prepare raw meal balls;

s2, calcining the raw material balls at 1200-1400 ℃ for 25-60 min;

s3, sieving the powder with a sieve of 150 mu m to obtain a residue sieve of not more than 2 wt% and a specific surface area of 250-350 square meters per kg, thus obtaining the finished product.

8. The temperature-controlled concrete expanding agent according to claim 7, wherein the calcination temperature in step S2 is 1350 ℃ and the calcination time is 35 min.

9. The temperature-controlled concrete expansive agent according to claim 1, which comprises 95 wt% of the expanded compact component and 5 wt% of the temperature-controlled component.

10. The temperature-controlled concrete expanding agent according to claim 1, wherein the gypsum is anhydrite, and the density of the silica fume is 500-700 kg/m³The retarder is at least one of sodium gluconate, sodium tripolyphosphate, sodium polyphosphate, sodium hexametaphosphate and sodium pyrophosphate.

Technical Field

The invention belongs to the field of concrete admixtures, and particularly relates to a temperature-controlled concrete expanding agent.

Background

In concrete engineering, particularly in large-volume and high-grade concrete, a large amount of hydration heat is generated by early hydration of cement-based materials, and the internal temperature of the concrete is sharply increased. The concrete can reach a temperature peak within 1-2 days generally, the temperature peak of the central part of the concrete is generally 40-60 ℃ in a common concrete structure with the label less than C40 and the minimum section size less than 1.0m in civil engineering; and the temperature of high-grade and large-volume concrete or concrete in summer construction can even reach 60-70 ℃.

The environment temperature suitable for concrete construction is usually 5-30 ℃, but the day and night temperature difference in some areas can reach more than 20 ℃. When the temperature difference between the inside and the outside of the concrete is too large, large temperature shrinkage stress can be generated in the temperature reduction stage, so that the concrete cracks, and the structural safety of the concrete is seriously influenced. For the above reasons, it is a common technical means in the art to solve the problem of reducing the temperature difference between the inside and outside of the concrete and compensating the shrinkage of the concrete structure.

The expanding agent is a common admixture for cement-based materials and is commonly used in the formulation of shrinkage-compensating concrete. The expansion sources of the current expanding agent mainly comprise two main types, one is calcium sulphoaluminate, calcium oxide and calcium sulphoaluminate-calcium oxide, and the other is magnesium oxide; in addition, there have been attempts to compound calcium aluminothioate, calcium oxide, calcium aluminothioate-calcium oxide, and magnesium oxide. The drawbacks of these swelling agents are: the calcareous expanding agent has larger expansion energy at the temperature of 20 ℃, but has faster reaction rate, and the reaction rate is too fast at the temperature of 40-60 ℃; although the magnesium expanding agent solves the problem of excessively high reaction rate at 40-60 ℃, the expansion amount of the magnesium expanding agent is smaller than that of a calcium expanding agent, the viscosity of the concrete after the magnesium expanding agent is doped is increased, and the using amount of a water reducing agent in the concrete can be increased.

In the field of concrete expanding agents, the Chinese granted patent CN104692693B provides a modified calcium oxide expansion clinker which is prepared by mixing and grinding the calcium oxide expansion clinker and calcium phosphate for modification, the reaction rate of the prepared modified calcium oxide expansion clinker is slower than that before modification, but tests are all carried out under the condition of 20 ℃ maintenance, the test data of the modified calcium oxide expansion clinker under the relatively high-temperature condition of 40-60 ℃ is not mentioned, and the mixing and grinding process under the liquid-phase condition has higher industrial amplification cost and is difficult to implement.

The Chinese granted patent CN103496867B provides a calcium sulphoaluminate or calcium sulphoaluminate-calcium oxide concrete expanding agent, the expansion limiting rate test of the concrete expanding agent is carried out under the condition of 20 ℃, test data under the condition of relatively high temperature curing at 40-60 ℃ are also lacked, and the improvement of the expansion limiting rate reaction rate under the condition of 40-60 ℃ is very small according to the reaction rate under the condition of 20 ℃.

The Chinese patent application CN109231866A provides a hydration heat inhibited concrete expanding agent, wherein the hydration heat inhibited expanding clinker adopts metal oxide, the reaction rate of the clinker for limiting the expansion rate under the condition of 20 ℃ can be reduced to a certain extent, the improvement of the reaction rate for limiting the expansion rate under the condition of 40-60 ℃ is estimated to be very small according to the reaction rate under the condition of 20 ℃, and the metal oxide has high cost and is difficult to produce and implement.

The Chinese granted patent CN103342494A is a hydration heat inhibited concrete expansive material, wherein the expansive agent is partially and completely made of a calcium expansive agent, although attention is paid to high-temperature curing conditions, no attention is paid to the problem of reaction rate of the calcium expansive agent at different ages at 40-60 ℃, and in addition, although a certain humidity is provided in a cement-based material system by the compounded internal curing agent, whether the action effect is the same or not along with the increase of the internal temperature of concrete is not fully described.

In the aspect of relating to temperature control materials, a Chinese granted patent CN104592403A provides a hydration heat regulator, the hydration heat regulator is obtained by polymerization and crosslinking of dextrin and a crosslinking agent, the examples of the hydration heat regulator are compared under the condition of 20-40 ℃, and the examples of how to reduce and delay the temperature peak under the condition of 40-60 ℃ common in concrete engineering do not have corresponding examples, and hydration heat data of the hydration heat regulator in different ages in cement-based materials are not tested.

In the above-mentioned prior art, there is a material obtained by compounding a swelling agent with a hydration heat inhibitor, but the problem of the swelling reaction rate of the swelling agent at 40 to 60 ℃ is not sufficiently considered. On the other hand, the control of the hydration heat of the cement-based material is more and more concerned about the current crack control of the concrete structure; in addition, based on the requirements on the turnover of concrete formworks and the field propulsion, the problem of early form removal exists in most concrete projects, so how to reduce the temperature difference between the inside and the outside of concrete is not negligible in concrete crack control.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a temperature control type concrete expanding agent, which is realized by the following technology.

A temperature control type concrete expanding agent comprises 90-99 wt% of an expanded compact component and 1-10 wt% of a temperature control component;

the expansion dense component comprises 55-92 wt% of hydration regulation type calcium oxide-calcium sulphoaluminate expansion clinker, 5-30 wt% of gypsum and 3-15 wt% of silica fume;

the temperature control component comprises 2-80 wt% of an inhibition component I, 5-50 wt% of an inhibition component II, 10-50 wt% of an inhibition component III, 1-50 wt% of an adjustment component I and 1-10 wt% of an adjustment component II;

the inhibiting component I is a hydroxypropyl compound (namely a non-ester hydroxypropyl compound) with the intramolecular hydroxypropyl number not less than 1 and the ester group not more than 0;

the inhibiting component II is a hydroxypropyl ester compound with the intramolecular hydroxypropyl number not less than 1 and the ester group not less than 1;

the inhibiting component III is a polyhydric alcohol compound which has more than or equal to 2 intramolecular hydroxyl groups and does not contain hydroxypropyl;

the specific surface area of the regulating component I is more than or equal to 500m²/kg of superfine mineral powder;

the adjusting component II is a retarder.

The temperature control type expanding agent provided by the invention can ensure the total amount of expansion energy under the same mixing amount and can regulate and control the expansion reaction rate by selecting reasonable expansion compact components, thereby better meeting the engineering requirements. In addition, the introduction of the temperature control component can reduce and delay the hydration reaction rate of the cement-based material. In the temperature control components, the inhibiting components I and II can reduce the hydration reaction rate of cement, and the inhibiting component III can reduce the hydration reaction rate of the cement and delay the time of the hydration reaction, so that the inhibiting component I, the inhibiting component II, the inhibiting component III and the temperature control component cooperate to achieve better hydration heat delay and reduction effects; and the two components are used in a compounding way by reasonably adjusting the proportion of the expansion clinker according to the possible shrinkage size and the size of the concrete structure, so that the expansion clinker is better suitable for the concrete structures with different labels, positions, sizes and construction conditions, and the working performance of the concrete can meet the construction requirements. Wherein, the adjusting component I can improve the flow property of the cement-based material, and the adjusting component II can adjust the setting time of the cement-based material. The temperature control component and the expanded compact component are compounded to play a synergistic role, so that the temperature stress in the cement-based material is further reduced from the generation source of the temperature stress, and the cracking phenomenon of a concrete structure due to overlarge temperature stress is reduced.

The preparation method of the expanding agent comprises the steps of respectively and uniformly mixing the raw materials of the expanded compact component and the temperature control component, and then uniformly mixing the expanded compact component and the temperature control component to obtain a finished product.

Preferably, the temperature control component comprises 45 wt% of inhibiting component I, 20 wt% of inhibiting component II, 20 wt% of inhibiting component III, 10 wt% of regulating component I and 5 wt% of regulating component II.

Preferably, the inhibiting component I is at least one of hydroxypropyl cellulose, hydroxypropyl starch, hydroxypropyl guar gum, hydroxypropyl-beta-cyclodextrin and hydroxypropyl methyl cellulose; the inhibiting component II is at least one of hydroxypropyl distarch phosphate and hydroxypropyl acrylate; the inhibiting component III is at least one of glucose, fructose, mannitol, glycerol, erythritol, xylitol, galactitol and sorbitol;

the regulating component I is superfine mineral powder with the specific surface area of more than or equal to 500 square meters per kg; the adjusting component II is at least one of sodium gluconate, sodium tripolyphosphate, sodium polyphosphate, sodium hexametaphosphate and sodium pyrophosphate.

Preferably, the raw material proportion of the hydration regulation type calcium oxide-calcium sulfoaluminate expansion clinker before firing comprises the following raw materials with specific surface area of more than or equal to 350 square meters per kg: 65-80 wt% of limestone, 5-15 wt% of gypsum, 2-5 wt% of iron slag, 6-15 wt% of alumina, and 7-20 wt% of a non-metal oxide or a composite of a non-metal oxide and a metal oxide. The nonmetal oxide can modify the hydration reaction of the calcium oxide-calcium sulphoaluminate expansion clinker, so that the calcium oxide-calcium sulphoaluminate expansion clinker can linearly and stably react at 40-60 ℃, and the metal oxide is matched to have good balling effect during calcination under the condition of equivalent modification effect, so that the kiln wall skinning phenomenon during calcination is reduced, the calcination temperature is reduced, and the clinker calcination cost is further reduced.

The temperature-controlled concrete expanding agent provided by the invention creatively integrates the calcium expanded clinker modified by nonmetal and metal ions, gypsum and silica fume into an expanded compact component, and combines the temperature-controlled component together, so that the prepared concrete can also play a good effect of limiting the expansion rate under the condition of 40-60 ℃.

More preferably, the mixture ratio of the raw materials of the hydration regulation type calcium oxide-calcium sulfoaluminate expansive clinker before firing comprises the following raw materials with specific surface area of more than or equal to 350 square meters per kg: 70 wt% of limestone, 7 wt% of gypsum, 3 wt% of iron slag, 9 wt% of alumina and 11 wt% of non-metal oxide or composite of non-metal oxide and metal oxide.

More preferably, the non-metal oxide comprises at least one of the oxides of P, Si, other non-metal oxides may also be employed; the metal oxide contains at least one of oxides of Mg, Zn, Fe, Cu, and other metal oxides may be used.

More preferably, the preparation method of the hydration regulation type calcium oxide-calcium sulfoaluminate expansion clinker comprises the following steps:

s1, mixing all the raw meal powder uniformly, and adding water to prepare raw meal balls;

s2, calcining the raw material balls at 1200-1400 ℃ for 25-60 min;

s3, sieving the powder with a sieve of 150 mu m to obtain a residue sieve of not more than 2 wt% and a specific surface area of 250-350 square meters per kg, thus obtaining the finished product.

More preferably, the calcination temperature in step S2 is 1350 ℃ and the calcination time is 35 min.

Preferably, the temperature control type concrete expanding agent comprises 95 wt% of an expanded compact component and 5 wt% of a temperature control component.

Preferably, the gypsum is anhydrite, and the density of the silica fume is 500-700 kg/m³The retarder is at least one of sodium gluconate, sodium tripolyphosphate, sodium polyphosphate, sodium hexametaphosphate and sodium pyrophosphate.

Preferably, the preparation method of the hydration regulation type calcium oxide-calcium sulfoaluminate expansion clinker comprises the following steps:

s1, mixing all the raw meal powder uniformly, and adding water to prepare raw meal balls;

s2, calcining the raw material balls at 1200-1400 ℃ for 25-60 min;

s3, sieving the powder with a sieve of 150 mu m to obtain a residue sieve of not more than 2 wt% and a specific surface area of 250-350 square meters per kg, thus obtaining the finished product.

Preferably, the nonmetal oxide is at least one of P, Si oxides, and the metal oxide is at least one of Mg, Zn, Fe and Cu oxides.

Preferably, 95 wt% of the expanded compact component and 5 wt% of the temperature-controlled component are included.

Preferably, the raw material proportion of the hydration regulation type calcium oxide-calcium sulfoaluminate expansion clinker before firing comprises the following raw materials with specific surface area of more than or equal to 350 square meters per kg: 70 wt% of limestone, 7 wt% of gypsum, 3 wt% of iron slag, 9 wt% of alumina and 11 wt% of non-metal oxide or composite of non-metal oxide and metal oxide.

Preferably, the temperature control component comprises 50 wt% of an inhibiting component I, 20 wt% of an inhibiting component II, 20 wt% of an inhibiting component III, 5 wt% of an adjusting component I and 5 wt% of an adjusting component II;

preferably, the inhibiting component I is at least one of hydroxypropyl cellulose, hydroxypropyl starch, hydroxypropyl guar gum, hydroxypropyl-beta-cyclodextrin and hydroxypropyl methyl cellulose; the inhibiting component II is at least one of hydroxypropyl distarch phosphate and hydroxypropyl acrylate; the inhibiting component III is at least one of glucose, fructose, mannitol, glycerol, erythritol, xylitol, galactitol and sorbitol;

the regulating component I is superfine mineral powder with the specific surface area of more than or equal to 500 square meters per kg; the adjusting component II is at least one of sodium gluconate, sodium tripolyphosphate, sodium polyphosphate, sodium hexametaphosphate and sodium pyrophosphate.

Preferably, the gypsum is anhydrite, and the density of the silica fume is 500-700 kg/m 3.

Preferably, the retarder is at least one of sodium gluconate, sodium tripolyphosphate, sodium polyphosphate, sodium hexametaphosphate and sodium pyrophosphate.

Compared with the prior art, the invention has the advantages that: the expansion dense component and the temperature control component in a special proportion are adopted, so that the temperature stress in the cement-based material can be reduced, the expansion reaction rate can be reasonably regulated and controlled at normal temperature and at 40-60 ℃, the hydration reaction rate of the cement-based material is reduced and delayed, the cracking phenomenon of a concrete structure due to overlarge temperature stress is reduced, and the engineering requirement is better met.

Detailed Description

The technical solutions of the present invention will be described clearly and completely below, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The following examples and comparative examples were prepared according to the following raw materials and preparation recipes, unless otherwise specified.

The preparation method of the hydration regulation type calcium oxide-calcium sulphoaluminate expansion clinker comprises the following steps:

s1, mixing all the raw meal powder uniformly, and adding water to prepare raw meal balls;

s2, calcining the raw material balls at 1350 ℃ for 35 min;

s3, sieving the powder with a sieve of 150 mu m to obtain a residue sieve of not more than 2 wt% and a specific surface area of 250-350 square meters per kg, thus obtaining the finished product.

The inhibition component I is hydroxypropyl cellulose, the inhibition component II is hydroxypropyl distarch phosphate, the inhibition component III is glucose and xylitol according to the weight ratio of 1:1, the regulation component I is superfine mineral powder with the specific surface area not less than 500 square meters per kg, and the regulation component II is sodium gluconate.

The production places of the raw materials used in the following examples and comparative examples were respectively: limestone and iron slag come from Zhejiang, gypsum, alumina and silica fume come from Hubei, a commercially available HCSA concrete expanding agent comes from Beijing of China, phosphorus pentoxide, zinc oxide, hydroxypropyl cellulose, hydroxypropyl distarch phosphate, glucose and xylitol come from Shanghai, and sodium gluconate comes from Tianjin.

The temperature control concrete expanding agent of the following examples and comparative examples is prepared by uniformly mixing the formulas of the expansive compact components, uniformly mixing the formulas of the temperature control components, and uniformly mixing the expansive compact components and the temperature control components.