Internal curing high performance cement concrete and method of making

Abstract

The application discloses an internal curing high-performance cement concrete and a preparation method thereof, and belongs to the technical field of building materials. The internal curing high-performance cement concrete comprises cement, fly ash, mineral powder, crushed stone and a water reducing agent, and further comprises an internal curing agent. The internal curing agent accounts for 0.18-0.3% of the mass of the cement. The internal curing agent is prepared from 3-(isobutenyl amide) propyl trimethyl ammonium chloride, an acrylic compound and modified zeolite. The internal curing high-performance cement concrete provided by the application has a simple preparation process. Compared with ordinary concrete, the incorporation of the internal curing agent can improve the working performance of the concrete, reduce the shrinkage rate of the concrete by more than 40%, reduce the early cracking rate of the concrete by more than 30%, and reduce the curing cost by more than 60% because the concrete only needs to be watered once every three days. After the concrete is put into service, a large amount of bridge maintenance cost can be saved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of building materials, and particularly relates to an internal curing high-performance cement concrete and a preparation method thereof. BACKGROUND

[0002] Concrete is one of the most important materials in civil engineering and construction, which is a kind of artificial stone obtained by mixing cementitious materials, aggregates, water, and necessary admixtures and additives according to the specified proportion, uniformly stirring, and compacting. Due to its good mechanical properties, it is widely used in long-span bridges and key projects, and the formation of its strength and durability is directly related to the quality of the above-mentioned buildings.

[0003] The strength and durability of concrete are closely related to the selection of cementitious materials, water-cement ratio, and age, and are also related to the curing method of concrete. After pouring, concrete can gradually harden and solidify mainly because of the hydration of cement, which requires appropriate temperature and humidity conditions. Therefore, in order to ensure that concrete has suitable hardening conditions and its strength continues to grow, it is necessary to cure the concrete. In hot and humid climates such as Guangxi, due to the objective climate, the hydration reaction and water evaporation of concrete are fast, and the service environment is complex, the construction quality and durability guarantee are facing severe challenges. The water in the concrete evaporates too quickly, forming a dehydration phenomenon, which makes the cement particles that have formed a gel body unable to fully hydrate and cannot be converted into stable crystals, lacking sufficient adhesion, and thus appearing as flaky or powdery shedding on the surface of the concrete. In addition, when the concrete does not have enough strength, the premature evaporation of water will also produce a large shrinkage deformation and dry shrinkage cracks.

[0004] The traditional curing method of concrete generally uses external curing, which only cures the surface, and has potential problems such as untimely shrinkage reduction, low water retention rate, poor film water solubility, and incomplete curing. After being affected by temperature, it is easy to appear peeling, shedding, cracking and other phenomena, resulting in frequent concrete structure diseases during the service period. The current research believes that the most feasible and effective method is to compensate for the water required for hydration from the inside of the concrete, that is, internal curing or self-curing. The comparison diagram of the traditional curing method of concrete and the internal curing method is shown in Figure 1The internal curing material is a material with a porous structure, which has a large number of pores or three-dimensional space network structures, can adjust and convert the water storage and release functions through external conditions and its own capillary or functional groups, and plays the role of an internal reservoir. When there is insufficient water in the hydration process of the concrete, the water in the internal curing material supplies the water required for hydration, so as to maintain the hydration reaction in the system. The existing internal curing method mostly uses superabsorbent polymers, which contain a large number of carboxyl, amide, hydroxyl and other strong hydrophilic groups, can absorb more than 100 times of water, can continuously release water during the hydration process of cement, can ensure further hydration of cement, and can prevent early shrinkage and cracking of concrete. However, the water absorption rate is fast, which can easily affect the working performance and strength development of the concrete, in addition, the water absorption resin has high requirements for the internal environment of the concrete, if the internal alkaline environment of the concrete is unstable, the water absorption resin cannot stably release water, which leads to large changes in the water-binder ratio of the concrete, and further affects the working performance of the concrete. As can be seen, the internal curing agent used in the existing concrete cannot control the water absorption rate, and does not have the performance of resisting strong alkali and controlling the water absorption rate in the controlled strong alkaline environment. SUMMARY

[0005] The purpose of the present application is to provide an internal curing high-performance cement concrete and a preparation method thereof, so as to solve the problems existing in the prior art. Through the comprehensive curing method of internal curing and external resistance, the shrinkage and cracking of the concrete are relieved, and the durability and appearance quality of the concrete are improved.

[0006] One of the technical solutions provided by the present application is:

[0007] An internal curing high-performance cement concrete, which comprises cement 200-300 parts, fly ash 80-100 parts, mineral powder 600-700 parts, gravel 1000-1300 parts and water reducing agent 3-5 parts, and the water-binder ratio is 0.35-0.37, and further comprises an internal curing agent, the internal curing agent has a content of 2% of the mass of the cement, and the preparation raw material of the internal curing agent comprises 3-(isobutenyl amide) propyl trimethyl ammonium chloride, an acrylic compound, an acrylamide compound and modified zeolite.

[0008] Preferably, the preparation method of the modified zeolite comprises the following steps: adding zeolite into an ammonium nitrate solution, heating and reacting, filtering and washing, and then calcining, and then sequentially performing high-temperature water vapor treatment and acid treatment on the calcined zeolite to obtain the modified zeolite.

[0009] In the present application, the zeolite sample is directly calcined after ammonium exchange, and the silicon-aluminum ratio of the zeolite is improved through the organic combination of high-temperature water vapor treatment and liquid-phase acid treatment, so as to further improve the stability of the zeolite, and the specific surface area of the zeolite can also be maintained, and the amorphous aluminum impurities outside the framework can be removed through acid treatment, and strong acid sites and secondary mesopores are also generated.

[0010] More preferably, the molar concentration of the ammonium nitrate solution is 1 mol / L.

[0011] More preferably, the heating reaction temperature is 75℃ and the time is 4h.

[0012] More preferably, the calcination temperature is 480℃ and the time is 4.5h.

[0013] More preferably, the high-temperature water vapor treatment method is as follows: the calcined zeolite is placed in a quartz boat and put into a tube furnace to be heated to 600℃, then water vapor is introduced (flow rate is 50 mL / min) for 4h.

[0014] More preferably, the acid treatment uses a citric acid solution, and the specific treatment method is as follows: the high-temperature water vapor treated zeolite is placed in a citric acid solution (0.03 mol / L), stirred, filtered, washed and dried to obtain the modified zeolite.

[0015] Preferably, the preparation method of the internal curing agent is as follows: the persulfate salt is added to the aqueous solution of 3-(isobutenylamide) propyl trimethyl ammonium chloride, and after water bath reaction, the product is washed with acetone, the acetone is filtered off, and the solid polymer is washed with ethanol to obtain a water absorption polymer solution. The modified zeolite is added to the water absorption polymer solution, soaked, taken out, dried at room temperature, heated in a microwave reactor, and dried to constant weight to obtain the internal curing agent.

[0016] More preferably, the amount of the persulfate salt accounts for 0.5-1wt% of the 3-(isobutenylamide) propyl trimethyl ammonium chloride.

[0017] More preferably, the mass ratio of the solid polymer, the acrylamide compound monomer, the initiator and the crosslinking agent is (5-10) : (5-10) : (0.05-0.18) : (0.006-0.01).

[0018] More preferably, the water bath reaction temperature is 70-80℃ and the time is 4h.

[0019] More preferably, the heating reaction temperature is 60-75℃ and the time is 2-4h.

[0020] More preferably, the modified zeolite accounts for 2-3% of the mass of the water absorption polymer solution.

[0021] The solution formed due to cement hydration is strongly alkaline, and high concentration of high valence ions exist, which reduces the main driving force of water absorption of the water-absorbing high polymer, and significant shrinkage and water release may occur, which leads to the increase of the water binder ratio of the concrete, and influences the working performance of the concrete and even leads to complete failure. The modified zeolite with stable specific surface area and strong acid sites is added into the water-absorbing high polymer solution, in the soaking process, the polymer enters and is adsorbed in the modified zeolite, based on the limitation of the pore size of the zeolite, the water absorption rate of the polymer is controlled, and when the alkalinity of the concrete environment is too large, the strong acid sites in the modified zeolite and the adsorption of the zeolite to the high valence ions can alleviate the adverse effects of the strong alkaline environment on the water-absorbing high polymer, maintain the osmotic pressure, avoid the problem of shrinkage and water release of the high polymer after water absorption, maintain the water binder ratio of the concrete, and ensure the working performance of the concrete.

[0022] The second technical solution provided by the present application is as follows:

[0023] The preparation method of the internal curing high-performance cement concrete provided by the present application is simple, compared with ordinary concrete, the incorporation of the internal curing agent can improve the working performance of the concrete, reduce the shrinkage rate of the concrete by more than 40%, reduce the early cracking rate by more than 30%, the curing of the concrete only needs to be watered once every 3 days, the curing cost is reduced by more than 60%, and a large amount of bridge deck maintenance cost can be saved after the concrete is put into service.

[0024] The present application has the following advantages:

[0025] The preparation process of the internal curing high-performance cement concrete provided by the present application is simple, compared with ordinary concrete, the incorporation of the internal curing agent can improve the working performance of the concrete, reduce the shrinkage rate of the concrete by more than 40%, reduce the early cracking rate by more than 30%, the curing of the concrete only needs to be watered once every 3 days, the curing cost is reduced by more than 60%, and a large amount of bridge deck maintenance cost can be saved after the concrete is put into service.

[0026] The present application combines the high molecular polymer with water absorption, water retention and water release with the modified zeolite, prepares the internal curing agent, adds the internal curing agent into the concrete, and plays the role of the curing factor; the water-absorbing high polymer can adsorb the free water in the concrete, lock the surface water evaporation, due to the limitation of the pore size of the modified zeolite, the water absorption rate of the polymer is controlled, the adsorbed water is gradually released in the cement hydration process, the supply of water in the concrete is ensured, the local capillary pore humidity saturation is maintained, the hydration humidity environment of the concrete is improved, and the water content and structure density are improved; when the alkalinity and ion concentration of the concrete increase due to the hydration, the stable specific surface area and strong acid sites of the modified zeolite can alleviate the influence of the strong alkali and high ion concentration environment on the water release rate of the water-absorbing high polymer, and avoid the problem of severe shrinkage and water release of the high molecular polymer.

[0027] The application realizes the control of the water absorption rate of internal curing agent, reduces the influence of strong alkali and high ion concentration on water release, can effectively control the hydration heat of mass concrete, thereby significantly improving the homogeneity of concrete, greatly reducing the cracking tendency, improving the service life, and effectively improving the appearance quality and durability of concrete. BRIEF DESCRIPTION OF DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments will be briefly introduced below. Obviously, the drawings in the following description only constitute some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0029] Figure 1 A comparison diagram of the traditional curing method and the internal curing method for concrete;

[0030] Figure 2 A process flow diagram for preparing modified zeolite in Example 1. DETAILED DESCRIPTION

[0031] The various exemplary embodiments of the present application will now be described in detail, which should not be considered as limiting the present application, but should be understood as a more detailed description of some aspects, characteristics and embodiments of the present application.

[0032] It should be understood that the terms described in the present application are only for describing the specific embodiments, and are not used to limit the present application. In addition, for the numerical range in the present application, it should be understood that each intermediate value between the upper limit and the lower limit of the range is also specifically disclosed. Each smaller range between any stated value or intermediate value in the range and any other stated value or intermediate value in the range is also included in the present application. The upper limit and the lower limit of these smaller ranges can be independently included or excluded from the range.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application pertains. Although preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present application. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials in connection with which the documents are concerned. In the event of any conflict between the content of this specification and the documents incorporated by reference, the content of this specification will control.

[0034] Many modifications and variations of the specific embodiments of the application can be practiced in accordance with the teachings of the description of the application, which are within the scope of the present application. Other embodiments of the application will be apparent to those skilled in the art from consideration of the specification and practice of the application disclosed herein. The specification and examples of the application are exemplary only.

[0035] As used herein, the terms "comprises", "comprising", "includes", "including", "has", "having" or the like are open-ended expressions that are intended to denote the presence of stated features, items, elements, components, or the like but do not preclude the presence or addition of one or more other features, items, elements, components, or the like.

[0036] Room temperature of the present application refers to 25±2℃.

[0037] The raw materials required in the embodiments of the present application are all purchased, wherein the persulfate salt in the embodiments is potassium persulfate; the acrylamide compound monomer is N-hydroxymethyl acrylamide; the acrylic compound is methyl methacrylate; the initiator is ammonium persulfate; the crosslinking agent is N,N'-methylene bisacrylamide; the cement is ordinary Portland cement 42.5; the fly ash is grade III fly ash meeting the requirements of national standards; and the water reducing agent is a polycarboxylic acid high-performance water reducing agent.

[0038] Example 1: Preparation method of an internal curing agent

[0039] S1. 15 g of zeolite was added to 800 mL of an ammonium nitrate solution (1 mol / L) and reacted at 75℃ for 4 h. The reaction solution was filtered and washed to obtain an ammonium-exchanged zeolite sample, which was placed in a muffle furnace and calcined at 480℃ for 4.5 h. The above operation was repeated twice. 10 g of zeolite obtained by calcination in the last time was placed in a quartz boat, which was then placed in a tube furnace and heated to 600℃. Then, water vapor was introduced at a flow rate of 50 mL / min, and the high-temperature water-treated zeolite was obtained after 4 h of treatment. The high-temperature water-treated zeolite was placed in 200 mL of a citric acid solution (0.03 mol / L) and treated under magnetic stirring for 4 h. Then, it was filtered, washed with deionized water, and dried at 120℃ to constant weight to obtain the modified zeolite. The process flow chart for preparing the modified zeolite is shown in Figure 2 .

[0040] S2. 3-(isobutenylamide) propyl trimethyl ammonium chloride with a concentration of 30 wt% was placed in a flask, and 0.5% of potassium persulfate by mass was added. The water bath temperature was 80℃, and the reaction was carried out for 4 h. The product was washed with acetone, and the acetone was filtered out. Then, the product was washed with anhydrous ethanol twice to obtain a solid polymer.

[0041] S3. Sodium hydroxide solution 30 mL (5 mol / L) at 0±2℃ was added into a three-necked flask, 10 g of methacrylic acid was added for neutralization reaction, after the reaction was completed, 5 g of solid polymer, 10 g of N-methylol acrylamide, 0.05 g of ammonium persulfate and 0.01 g of N,N'-methylenebisacrylamide were added in turn, and were fully stirred and dissolved, 0.5 g of Span 80 was added into the three-necked flask, and nitrogen was introduced, and the reaction was carried out at 60℃ for 2 h, the heating was stopped, and the stirring was continued until room temperature, to obtain a water-absorbing polymer solution;

[0042] S4. The modified zeolite prepared in S1 was added into the water-absorbing polymer solution obtained in S3, and was soaked for 1 h, the modified zeolite accounted for 3% of the mass of the water-absorbing polymer solution, the water-absorbing polymer was adsorbed in the modified zeolite, and the water-absorbing and water-releasing properties of the water-absorbing polymer were retained;

[0043] S5. After the product obtained in S4 was dried at room temperature, it was heated and dried to constant weight in a microwave reactor, to obtain the internal curing agent, and after grinding and sieving, the internal curing agent was a particulate matter with an average particle size of 75±5 μm.

[0044] Preparation method of an internal curing agent

[0045] S1. 20 g of zeolite was added into 1000 mL of ammonium nitrate solution (1 mol / L), and the reaction was carried out at 75℃ for 4 h, the reaction solution was filtered and washed to obtain an ammonium-exchanged zeolite sample, which was placed in a muffle furnace and calcined at 480℃ for 4.5 h, and the above operation was repeated for 3 times, 15 g of zeolite obtained by the last calcination was placed in a quartz boat, and the quartz boat was placed in a tube furnace, and was heated to 600℃, then water vapor was introduced at a flow rate of 50 mL / min, and the treatment was carried out for 4 h, to obtain high-temperature water-treated zeolite, which was placed in 300 mL of citric acid solution (0.03 mol / L), and was treated under magnetic stirring for 4 h, then was filtered, washed with deionized water, and dried at 120℃ to constant weight, to obtain modified zeolite;

[0046] S2. 3-(isobutenylamide) propyltrimethylammonium chloride with a concentration of 30 wt% was placed in a flask, and 1% of potassium persulfate by mass was added, the water bath temperature was 75℃, the reaction was carried out for 4 h, the product was washed with acetone, the acetone was filtered off, and the product was washed with anhydrous ethanol for 2 times, to obtain a solid polymer;

[0047] S3. Sodium hydroxide solution 30 mL (5 mol / L) at 0±2℃ was added into a three-necked flask, 10 g of methacrylic acid was added for neutralization reaction, after the reaction was completed, 8 g of solid polymer, 5 g of N-methylol acrylamide, 0.18 g of ammonium persulfate and 0.007 g of N,N'-methylenebisacrylamide were added in turn, and were fully stirred and dissolved, 0.5 g of Span 80 was added into the three-necked flask, and nitrogen was introduced, and the reaction was carried out at 60℃ for 2 h, the heating was stopped, and the stirring was continued until room temperature, to obtain a water-absorbing polymer solution;

[0048] S4. The modified zeolite prepared in S1 was added into the water-absorbing polymer solution obtained in S3, and was soaked for 1 h, the modified zeolite accounted for 2% of the mass of the water-absorbing polymer solution, the water-absorbing polymer was adsorbed in the modified zeolite, and the water-absorbing and water-releasing properties of the water-absorbing polymer were retained;

[0049] S5. After the product obtained in S4 was dried at room temperature, it was heated and dried to constant weight in a microwave reactor, to obtain the internal curing agent, and after grinding and sieving, the internal curing agent was a particulate matter with an average particle size of 80±5 μm.

[0050] Example 3

[0051] S1. 15 g of zeolite was added into 800 mL of ammonium nitrate solution (1 mol / L), and the reaction was carried out at 75℃ for 4 h, the reaction solution was filtered and washed to obtain an ammonium-exchanged zeolite sample, which was placed in a muffle furnace and calcined at 480℃ for 4.5 h, and the above operation was repeated twice, 10 g of zeolite obtained by calcination for the last time was placed in a quartz boat, the quartz boat was placed in a tube furnace, and the temperature was raised to 600℃, then water vapor was introduced at a flow rate of 50 mL / min, and the treatment was carried out for 4 h, to obtain a high-temperature water-treated zeolite, which was placed in 200 mL of citric acid solution (0.03 mol / L), and was treated under magnetic stirring for 4 h, then was filtered, washed with deionized water, and dried at 120℃ to constant weight, to obtain a modified zeolite;

[0052] S2. 30 wt% of 3-(isobutenylamide) propyl trimethyl ammonium chloride was placed in a flask, 0.5% of potassium persulfate by mass of the 3-(isobutenylamide) propyl trimethyl ammonium chloride was added, the water bath temperature was 70℃, the reaction was carried out for 4 h, the product was washed with acetone, the acetone was filtered off, and the product was washed with anhydrous ethanol for 2 times, to obtain a solid polymer;

[0053] S3. Sodium hydroxide solution 30 mL (5 mol / L) at a temperature of 0±2°C was added to a three-necked flask, 10 g of methacrylic acid was added for neutralization reaction, after the reaction was completed, 10 g of solid polymer, 8 g of N-methylol acrylamide, 0.1 g of ammonium persulfate and 0.01 g of N,N'-methylenebisacrylamide were added in sequence, and were fully stirred and dissolved, Span 80 was added to the three-necked flask, and nitrogen was introduced, and the reaction was carried out at 60°C for 2 h, heating was stopped, and stirring was continued until room temperature was reached, to obtain a water-absorbing polymer solution;

[0054] S4. The modified zeolite prepared in S1 was added to the water-absorbing polymer solution obtained in S3, and was soaked for 1 h, the modified zeolite accounted for 2.2% of the mass of the water-absorbing polymer solution, and the water-absorbing polymer was adsorbed in the modified zeolite, and the water-absorbing and water-releasing properties of the water-absorbing polymer were retained;

[0055] S5. After the product obtained in S4 was dried at room temperature, it was heated and dried to a constant weight in a microwave reactor, to obtain the internal curing agent, and after grinding and sieving, the internal curing agent was a particulate matter with an average particle size of 85±5 μm.

[0056] Comparative Example 1

[0057] The same as in Example 1, except that the modified zeolite was not added, the water-absorbing polymer solution obtained was filtered, washed with anhydrous ethanol for 2 times, and placed in an oven, and dried at 110°C for 8 h, and the water-absorbing polymer after drying was ground in a ball mill to a spherical particle with a size of 75±5 μm.

[0058] Comparative Example 2

[0059] The same as in Example 1, except that the citric acid treatment in S1 was not carried out.

[0060] Comparative Example 3

[0061] The same as in Example 1, except that the high-temperature water treatment in S1 was not carried out.

[0062] Preparation method of internal curing high-performance cement concrete in Examples 4-7 and Comparative Examples 4-6

[0063] The internal curing agents prepared in Examples 1-3 and Comparative Examples 1-3 were added by an external dry mixing method (the amount of the internal curing agent added accounted for 0.2% of the mass of the cement), and were mixed according to the material proportions in Table 1 and the ordinary concrete mixing process.

[0064] Table 1

[0065]

[0066] The concrete prepared in the above Examples 4-7 and Comparative Examples 4-6 was subjected to performance tests, and the autogenous shrinkage was determined according to GB / T 50082-2009. The results are shown in Table 2.

[0067] Table 2

[0068]

[0069] As shown in Table 2, Example 7 did not add internal curing agent, and the autogenous shrinkage of Examples 4-5 was reduced by 46%, 47% and 61% respectively at 7 days, and by 41%, 44% and 47% respectively at 28 days, and the concrete shrinkage rate was reduced by more than 40%; and the autogenous shrinkage of Comparative Examples 4-6 and Example 7 was reduced by 8%, 13% and 17% respectively at 7 days, and by 15%, 17% and 10% respectively at 28 days, which was far less than Example 1.

[0070] The concrete early cracking rate test method was carried out according to the relevant provisions of the national standard "Standard for Testing Methods for Long-term Performance and Durability of Ordinary Concrete" GB / T50081. Two groups of concrete obtained from Examples 4-7 and Comparative Example 6 were formed, one group was the reference concrete, and the other group was sprayed with inorganic water-based permeable crystalline material as the tested concrete. The spraying method of the inorganic water-based permeable crystalline material was: after the test piece was finished and wind-blowed for 60 min, the inorganic water-based permeable crystalline material was sprayed after 30 min; the inorganic water-based permeable crystalline material was sprayed with a 500 mL spray bottle, the spraying amount was 250 ml / m 2 , and the amount of each flat plate cracking test piece was converted to 120 mL, sprayed every 7 min, 30 mL each time, and each flat plate test piece was sprayed for 4 times, the total amount was 120 mL. After the test was completed, the total cracking area on the unit area of the reference concrete was measured as C0, and the total cracking area on the unit area of the tested concrete was measured as C S . The test results are shown in Table 3.

[0071] The early cracking rate was calculated according to the following formula:

[0072]

[0073] In the formula: L-early cracking rate (%), the calculation result is retained to 1%;

[0074] C0-total cracking area on the unit area of the reference concrete (mm 2 / m 2 );

[0075] C s -total cracking area on the unit area of the tested concrete (mm 2 / m 2 ).

[0076] Table 3

[0077] Early crack rate (%) Example 4 9 Example 5 12 Example 6 16 Example 7 25 Comparative Example 4 20 Comparative Example 5 21 Comparative Example 6 19

[0078] From Table 3, it can be seen that the early crack reduction rate of Examples 4-6 compared with Example 7 is reduced by 64%, 52% and 36% respectively, and the early cracking rate is reduced by more than 30%, and the early crack reduction rate of Comparative Examples 4-6 compared with Example 7 is reduced by 20%, 16% and 24% respectively, and the early cracking rate reduction effect is far less than that of the examples.

[0079] The above-described examples are only to describe the preferred modes of the present application, and are not intended to limit the scope of the present application, and various modifications and improvements to the technical solutions of the present application made by those of ordinary skill in the art without departing from the design spirit of the present application shall fall within the protection scope determined by the claims of the present application.

Claims

1. An internally-cured high-performance cement concrete, comprising cement 200 parts by mass, fly ash 100 parts by mass, mineral powder 650 parts by mass, crushed stone 1200 parts by mass, and water reducing agent 5.0 parts by mass, with a water-binder ratio of 0.36, characterized in that, The internal curing agent is prepared from 3-(isobutenylamide) propyl trimethyl ammonium chloride, acrylic compound, acrylamide compound and modified zeolite. The modified zeolite is prepared by adding zeolite into ammonium nitrate solution, heating and reacting, filtering and washing, and then roasting, and then sequentially treating the roasted zeolite with high-temperature water vapor and acid to obtain the modified zeolite. The internal curing agent is prepared by adding persulfate into the aqueous solution of 3-(isobutenylamide) propyl trimethyl ammonium chloride, water-bath reacting, washing the product with acetone, filtering out the acetone, washing with ethanol to obtain solid polymer, adding the solid polymer, acrylamide compound monomer, initiator and crosslinking agent into the basic solution of the acrylic compound, heating and reacting, stopping heating after the reaction is completed, stirring to room temperature, obtaining the water-absorbing high-molecular polymer solution, adding the modified zeolite into the water-absorbing high-molecular polymer solution, soaking, taking out, drying at room temperature, and then heating in a microwave reactor until constant weight to obtain the internal curing agent.

2. The internally cured high performance cement concrete according to claim 1, characterized in that, The amount of the persulfate is 0.5-1wt% of the mass of the 3-(isobutenylamide) propyl trimethyl ammonium chloride.

3. The self-sustaining high performance cement concrete according to claim 1, wherein The mass ratio of the solid polymer, acrylamide compound monomer, initiator and crosslinking agent is (5-10)∶(5-10)∶(0.05-0.18)∶(0.006-0.01).

4. The self-sustaining high performance cement concrete according to claim 1, wherein The temperature of the water-bath reaction is 70-80℃, and the time is 4h.

5. The self-sustaining high performance cement concrete according to claim 1, wherein The temperature of the heating reaction in the preparation method of the internal curing agent is 60-75℃, and the time is 2-4h.

6. A method of producing the internally curing high performance cement concrete according to any one of claims 1 to 5, characterized in that, The internal curing agent is added by the external dry mixing method, and is mixed according to the ordinary concrete mixing process.

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