Special hydration temperature rise inhibitor for mass concrete and preparation method thereof

Abstract

The invention relates to the technical field of concrete admixtures, and discloses a hydration temperature rise inhibitor special for mass concrete and a preparation method of the hydration temperature rise inhibitor. Comprising the following raw materials in parts by weight: 95 to 105 parts of borax, 50 to 60 parts of triethanolamine, 90 to 110 parts of gluconate, 190 to 200 parts of polycarboxylic acid and 95 to 105 parts of carboxyl-terminated hyperbranched polyester. According to the invention, by adopting the admixture to reduce hydration heat and prolong final setting time, the defects of large and concentrated heat release of common concrete and complex process, high cost and poor structural integrity of the traditional construction technology can be overcome, the problem of easy generation of temperature cracks in mass concrete is solved, the construction complexity is reduced, and the construction efficiency is improved. And the cracking phenomenon of mass concrete is improved, and the technical purposes of low cost, high efficiency and high adaptability are achieved.

Description

Technical Field

[0001] The invention relates to the technical field of concrete admixtures, and in particular to a special hydration temperature rise inhibitor for mass concrete and a preparation method thereof. Background Art

[0002] Due to its large volume, large-volume concrete will generate a lot of hydration heat when cement is hydrated. However, concrete is a poor heat conductor, so the internal heat is not easy to dissipate, resulting in a large temperature difference between the inside and outside of large-volume concrete structures and poor durability. If it cannot be properly controlled, it will cause concrete cracking, which is very harmful and directly affects the safety of the engineering structure.

[0003] At present, in actual engineering, concrete temperature control mainly adopts concrete mix design, pre-cooling aggregates, internally embedded cooling water pipes and thermal insulation maintenance to adjust the temperature history of concrete. These methods are cumbersome to construct and costly. In the prior art, inhibitors are also used as admixtures to regulate the hydration process of concrete, thereby achieving the purpose of reducing the temperature difference of concrete to control the risk of cracking. However, general admixtures will affect the setting time of cement in concrete, and easily cause deformation of concrete formwork, etc.

[0004] Normally, the skip-bin construction method, pre-buried cooling water pipes, layered pouring and block pouring are usually adopted in engineering. These means are all construction measures, which are suitable for solving the uneven temperature difference caused by large-volume concrete pouring. Since these construction techniques belong to complex construction processes, they are subject to subjective influences such as engineering calculation errors and negligence of technicians when used. By improving the exothermic condensation characteristics of cement, a variety of complex maintenance measures can be reduced and the problem of temperature cracks in large-volume concrete in subway stations can be solved. Therefore, the present invention provides a special hydration temperature rise inhibitor for large-volume concrete and a preparation method thereof. Summary of the invention

[0005] 1. Technical issues to be solved

[0006] In view of the deficiencies in the prior art, the present invention provides a special hydration temperature rise inhibitor for large-volume concrete and a preparation method thereof, which has the advantages of solving the problem that temperature cracks are easily generated in large-volume concrete, reducing the complexity of construction, and improving the cracking phenomenon of large-volume concrete, achieving the technical goals of low cost, high efficiency and high adaptability, thereby solving the problems in the background technology.

[0007] (II) Technical solution

[0008] In order to achieve the above advantages of solving the problem of temperature cracks in large-volume concrete, reducing the complexity of construction, improving the cracking phenomenon of large-volume concrete, and achieving the technical goals of low cost, high efficiency, and high adaptability, the specific technical solutions adopted by the present invention are as follows:

[0009] A special hydration temperature rise inhibitor for mass concrete, comprising the following raw materials in parts by weight:

[0010] 95-105 parts of borax, 50-60 parts of triethanolamine, 90-110 parts of gluconate, 190-200 parts of polycarboxylic acid and 95-105 parts of carboxyl-terminated hyperbranched polyester.

[0011] Furthermore, the gluconate is composed of any one of sodium gluconate or potassium gluconate or a mixture of the two.

[0012] According to another aspect of the present invention, a method for preparing a hydration temperature rise inhibitor for mass concrete is provided, the method comprising the following steps:

[0013] S1. Preparation of temperature inhibitor borax: placing the prepared borax stone powder and sulfuric acid in a reaction bottle for sufficient reaction, filtering out the residue to obtain a boric acid solution; heating and evaporating the boric acid solution to obtain a concentrated boric acid solution, and separating and drying the solid after crystallization, and storing it in a container for later use;

[0014] S2, preparing the polymerization agent triethanolamine: adding ethanolamine to a three-necked flask into which ammonia gas has been introduced in advance, and stirring continuously at room temperature; after stopping the introduction of nitrogen gas, adding ethylene oxide and stirring continuously, maintaining a constant temperature, obtaining the polymerization agent triethanolamine after complete reaction, and cooling the discharged material for purification for standby use;

[0015] S3, preparing a shrinkage-reducing water-reducing agent polycarboxylic acid: adding water and sodium methacrylic acid to a four-necked flask and heating to a preset temperature; continuing to drop ammonium persulfate, allyl polyethylene glycol, methacrylic acid and an initiator into the four-necked flask under the protection of a protective gas, continuing to react after the dropwise addition is completed, and adjusting the pH value after cooling to obtain a finished shrinkage-reducing water-reducing agent;

[0016] S4, preparing a carboxyl-terminated hyperbranched polyester: sequentially adding methylene succinic acid, toluenesulfonic acid and triethanolamine to a dimethylacetamide solvent, and reacting for a preset time under a nitrogen atmosphere to obtain a hydroxyl-terminated hyperbranched polyester; continuing to fully react the hydroxyl-terminated hyperbranched polyester, p-toluenesulfonic acid and trimellitic anhydride under a nitrogen atmosphere, and performing purification after the reaction to obtain a carboxyl-terminated hyperbranched polyester;

[0017] S5. Configure a multi-component composite system: Use a mixing process simulation algorithm to determine the optimal mixing parameters. Based on the optimal mixing parameters, add polymerizer triethanolamine, water, borax, gluconate, polycarboxylic acid and carboxyl hyperbranched polyester into the mixer in sequence for mixing to obtain a special hydration temperature rise inhibitor for large volume concrete.

[0018] Furthermore, in step S1, the weight proportion of borax powder is 120-150 parts, and the weight proportion of sulfuric acid is 300 parts.

[0019] Furthermore, in step S2, the weight portion of ethanolamine is 150-200 parts, the stirring time at room temperature is maintained for 30 minutes, the weight portion of ethylene oxide is 40-60 parts, and the constant temperature is 80°C.

[0020] Furthermore, in step S3, the weight proportion of water is 1700 parts, the weight proportion of sodium methacrylate sulfonate is 10-30 parts, the preset temperature is 80°C, the weight proportion of ammonium persulfate is 40-60 parts, the weight proportion of allyl polyethylene glycol is 1000-1100 parts, the weight proportion of methacrylic acid is 90-100 parts, and the weight proportion of the initiator is 560 parts; the addition of all components is completed within 5 minutes, the protective gas is nitrogen, and the reaction is continued for 2 hours after the addition is completed. Sodium hydroxide is used to adjust the pH value, and the pH value is adjusted to 7.

[0021] Furthermore, in step S4, the weight proportion of methylene succinic acid is 13 parts, the weight proportion of toluenesulfonic acid is 1 part, the weight proportion of triethanolamine is 30 parts, the preset reaction time under nitrogen atmosphere is 10 hours, the reaction temperature is 150°C, the weight proportion of hydroxyl-terminated hyperbranched polyester is 40 parts, the weight proportion of p-toluenesulfonic acid is 1 part, and the weight proportion of trimellitic anhydride is 10 parts.

[0022] Furthermore, the method of determining the optimal stirring parameters by using a mixing process simulation algorithm comprises the following steps:

[0023] The objective function is constructed with the optimization goals of maximizing mixing uniformity and minimizing energy consumption, and the input parameters are determined as stirring time, stirring speed and material properties; a three-dimensional model of the mixer is constructed, and boundary conditions and material characteristics are set;

[0024] Determine the initial stirring time and speed range, obtain the initial parameter set, and use the three-dimensional model of the mixer to simulate the flow field, particle distribution and mixing uniformity indicators under the current parameters;

[0025] Based on the optimization algorithm, the mixing time and speed parameters are updated according to the simulation results, a new parameter set is generated, and the updated uniformity index and energy consumption are calculated using the three-dimensional model of the mixer;

[0026] When the objective function value changes less than the set threshold or reaches the maximum number of iterations, the optimization is stopped to obtain the optimized optimal stirring time and stirring speed.

[0027] Furthermore, the expression of the objective function is:

[0028]

[0029] Where F represents the objective function value, λ1 and λ2 represent the mixing uniformity weight and energy consumption weight respectively, σ represents the standard deviation of the concentration of particles or components in the mixture, μ represents the average concentration of particles or components in the mixture, E represents the total energy consumption during the mixing process, and E max represents the rated maximum energy consumption of the mixer, N represents the total number of sample points, x i represents the component concentration at the sample point, T represents the torque applied by the mixer to the fluid, ω represents the rotation speed of the impeller, and t represents the stirring time.

[0030] Furthermore, in step S5, the weight proportion of the polymerization agent triethanolamine is 20 parts, the weight proportion of water is 950-1000 parts, the weight proportion of borax is 9-20 parts, the weight proportion of gluconate is 9-20 parts, the weight proportion of polycarboxylic acid is 5-6 parts, and the weight proportion of carboxyl hyperbranched polyester is 9-20 parts.

[0031] (III) Beneficial effects

[0032] Compared with the prior art, the present invention provides a special hydration temperature rise inhibitor for mass concrete and a preparation method thereof, which has the following beneficial effects:

[0033] (1) The present invention provides a concrete hydration temperature rise inhibitor which has a simple, efficient and green preparation process, good retarding properties, and will not affect the mechanical properties and durability of concrete. The invention can reduce the hydration heat and prolong the final setting time by using admixtures, thereby overcoming the shortcomings of ordinary concrete, such as large and concentrated heat release, complex traditional construction technology and process, high cost, and poor structural integrity. The invention solves the problem that large-volume concrete is prone to temperature cracks, reduces the complexity of construction, and improves the cracking phenomenon of large-volume concrete, thereby achieving the technical goal of low cost, high efficiency, and high adaptability.

[0034] (2) The present invention can accurately predict the particle distribution and flow field characteristics during the mixing process by utilizing a mixing process simulation algorithm, and determine the optimal stirring time and speed, thereby not only effectively improving the mixing uniformity, but also reducing production energy consumption, thereby ensuring the high quality and stability of the final product. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0036] Figure 1 The present invention is a flowchart of a method for preparing a special hydration temperature rise inhibitor for mass concrete according to an embodiment of the present invention. DETAILED DESCRIPTION

[0037] To further illustrate each embodiment, the present invention provides drawings, which are part of the disclosure of the present invention and are mainly used to illustrate the embodiments and can be used in conjunction with the relevant descriptions in the specification to explain the operating principles of the embodiments. With reference to these contents, ordinary technicians in the field should be able to understand other possible implementations and advantages of the present invention. The components in the figures are not drawn to scale, and similar component symbols are generally used to represent similar components.

[0038] According to an embodiment of the present invention, a hydration temperature rise inhibitor specifically for mass concrete and a preparation method thereof are provided.

[0039] The present invention is now further described in conjunction with the accompanying drawings and specific embodiments. According to one embodiment of the present invention, a special hydration temperature rise inhibitor for mass concrete is provided, comprising the following raw materials in parts by weight:

[0040] 95-105 parts of borax, 50-60 parts of triethanolamine, 90-110 parts of gluconate, 190-200 parts of polycarboxylic acid and 95-105 parts of carboxyl-terminated hyperbranched polyester, wherein the gluconate is composed of any one of sodium gluconate or potassium gluconate or a mixture of the two.

[0041] Mechanism of the present invention: In the present invention, the introduction of a polymerizing agent into the hydration temperature rise inhibitor helps to uniformly disperse the hydration exothermic inhibition component and the shrinkage-retarding admixture component, thereby improving the uniformity of the hydration temperature rise inhibitor. CTHP (carboxyl-terminated hyperbranched polyester) can promote the formation of AFt (ettringite), which will rapidly crystallize and cover the surface of cement particles, playing a retarding role. As the hydration reaction continues, the ettringite film will become thinner and cracks will appear, so that the ions and water in the cement paste can continue to react with C3A (tricalcium aluminate) through the film layer, thereby significantly delaying the final setting time of the cement paste. At the same time, the carboxyl hydroxyl group can promote the longitudinal growth of the ettringite crystal while inhibiting its radial growth. This is because the polar group will be adsorbed on the side of the ettringite crystal to form a coating, thereby inhibiting its width growth and making it thinner and longer. These ettringites will form a hard skeleton structure, fill in the pores of the cement, and the mechanical bite force between these radial crystal clusters can also promote the development of the early strength of the cement. Therefore, adding hyperbranched retarders can also optimize the structure of cement samples and improve their mechanical properties.

[0042] According to another embodiment of the present invention, Figure 1 As shown, a method for preparing a special hydration temperature rise inhibitor for mass concrete is provided, and the preparation method comprises the following steps:

[0043] S1. Preparation of temperature inhibitor borax: placing the prepared borax stone powder and sulfuric acid in a reaction bottle for sufficient reaction, filtering out the residue to obtain a boric acid solution; heating and evaporating the boric acid solution to obtain a concentrated boric acid solution, and separating and drying the solid after crystallization, and storing it in a container for later use;

[0044] Wherein, in step S1, the weight proportion of borax powder is 120-150 parts, and the weight proportion of sulfuric acid is 300 parts.

[0045] S2, preparing the polymerization agent triethanolamine: adding ethanolamine to a three-necked flask into which ammonia gas has been introduced in advance, and stirring continuously at room temperature; after stopping the introduction of nitrogen gas, adding ethylene oxide and stirring continuously, maintaining a constant temperature, obtaining the polymerization agent triethanolamine after complete reaction, and cooling the discharged material for purification for standby use;

[0046] Wherein, in step S2, the weight portion of ethanolamine is 150-200 parts, the stirring time at room temperature is maintained for 30 minutes, the weight portion of ethylene oxide is 40-60 parts, and the constant temperature is 80°C.

[0047] S3, preparing a shrinkage-reducing water-reducing agent polycarboxylic acid: adding water and sodium methacrylic acid to a four-necked flask and heating to a preset temperature; continuing to drop ammonium persulfate, allyl polyethylene glycol, methacrylic acid and an initiator into the four-necked flask under the protection of a protective gas, continuing to react after the dropwise addition is completed, and adjusting the pH value after cooling to obtain a finished shrinkage-reducing water-reducing agent;

[0048] Wherein, in step S3, the weight portion of water is 1700 parts, the weight portion of sodium methacrylate sulfonate is 10-30 parts, the preset temperature is 80°C, the weight portion of ammonium persulfate is 40-60 parts, the weight portion of allyl polyethylene glycol is 1000-1100 parts, the weight portion of methacrylic acid is 90-100 parts, and the weight portion of the initiator is 560 parts; the addition of all components is completed within 5 minutes, the protective gas is nitrogen, and the reaction is continued for 2 hours after the addition is completed. Sodium hydroxide is used to adjust the pH value, and the pH value is adjusted to 7.

[0049] S4, preparing a carboxyl-terminated hyperbranched polyester: sequentially adding methylene succinic acid, toluenesulfonic acid and triethanolamine to a dimethylacetamide solvent, and reacting for a preset time under a nitrogen atmosphere to obtain a hydroxyl-terminated hyperbranched polyester; continuing to fully react the hydroxyl-terminated hyperbranched polyester, p-toluenesulfonic acid and trimellitic anhydride under a nitrogen atmosphere, and performing purification after the reaction to obtain a carboxyl-terminated hyperbranched polyester;

[0050] Among them, in step S4, the weight proportion of methylene succinic acid is 13 parts, the weight proportion of toluenesulfonic acid is 1 part, the weight proportion of triethanolamine is 30 parts, the preset reaction time under nitrogen atmosphere is 10 hours, the reaction temperature is 150°C, the weight proportion of hydroxyl-terminated hyperbranched polyester is 40 parts, the weight proportion of p-toluenesulfonic acid is 1 part, and the weight proportion of trimellitic anhydride is 10 parts.

[0051] S5. Configure a multi-component composite system: Use a mixing process simulation algorithm to determine the optimal mixing parameters. Based on the optimal mixing parameters, add polymerizer triethanolamine, water, borax, gluconate, polycarboxylic acid and carboxyl hyperbranched polyester into the mixer in sequence for mixing to obtain a special hydration temperature rise inhibitor for large volume concrete.

[0052] Wherein, in step S5, the weight proportion of the polymerization agent triethanolamine is 20 parts, the weight proportion of water is 950-1000 parts, the weight proportion of borax is 9-20 parts, the weight proportion of gluconate is 9-20 parts, the weight proportion of polycarboxylic acid is 5-6 parts, and the weight proportion of carboxyl hyperbranched polyester is 9-20 parts.

[0053] The method of determining the optimal stirring parameters using the mixing process simulation algorithm includes the following steps:

[0054] The objective function is constructed with the optimization goals of maximizing mixing uniformity and minimizing energy consumption, and the input parameters are determined as stirring time, stirring speed and material properties; a three-dimensional model of the mixer is constructed, and boundary conditions and material characteristics are set; the expression of the objective function is:

[0055]

[0056] E=T·ω·t

[0057] Where F represents the objective function value, λ1 and λ2 represent the mixing uniformity weight and energy consumption weight respectively, σ represents the standard deviation of the concentration of particles or components in the mixture, μ represents the average concentration of particles or components in the mixture, E represents the total energy consumption during the mixing process, and E max represents the rated maximum energy consumption of the mixer, N represents the total number of sample points, x i represents the component concentration at the sample point, T represents the torque of the mixer acting on the fluid, ω represents the rotation speed of the stirring paddle, and t represents the stirring time;

[0058] Determine the initial stirring time and speed range, obtain the initial parameter set, and use the three-dimensional model of the mixer to simulate the flow field, particle distribution and mixing uniformity indicators under the current parameters;

[0059] Based on the optimization algorithm, the mixing time and speed parameters are updated according to the simulation results, a new parameter set is generated, and the updated uniformity index and energy consumption are calculated using the three-dimensional model of the mixer;

[0060] When the objective function value changes less than the set threshold or reaches the maximum number of iterations, the optimization is stopped to obtain the optimized optimal stirring time and stirring speed.

[0061] In order to facilitate understanding of the above technical solutions of the present invention, specific embodiments of the present invention are described in detail below.

[0062] Example 1

[0063] A method for preparing a special hydration temperature rise inhibitor for mass concrete, comprising a multi-component composite system admixture prepared from borax, triethanolamine, gluconate, polycarboxylic acid, and carboxyl-terminated hyperbranched polyester (CTHP), calculated by weight fraction:

[0064] Step 1: Prepare the temperature inhibitor borax: Add 120-150 parts of borax stone powder and 300 parts of sulfuric acid into a reaction bottle, filter out the residue after sufficient reaction, and obtain a boric acid solution. Heat the boric acid solution and evaporate it to obtain a concentrated boric acid solution. After crystallization, separate the solid and dry it, and store it in a container for later use.

[0065] Step 2: preparing the polymerization agent triethanolamine: introducing ammonia gas into a three-necked flask equipped with a thermometer, a stirrer and a reflux condenser in advance, adding 150-200 parts of ethanolamine, maintaining room temperature for 30 minutes and stirring continuously; after stopping the introduction of ammonia gas, gradually adding 40-60 parts of ethylene oxide through a dropper, stirring continuously during the reaction to ensure uniform mixing of the reaction, and maintaining a constant temperature of 80°C. After the reaction is complete, the polymerization agent triethanolamine is obtained, cooled and discharged, and purified for later use; the three-necked flask can be equipped with a thermometer, a stirrer and a reflux condenser at the same time during the reaction to meet the preparation requirements.

[0066] Step 3: Prepare a shrinkage-reducing water-reducing agent polycarboxylic acid: add 1700 parts of water and 10-30 parts of sodium methacrylate sulfonate to a four-necked flask, heat to 80 degrees Celsius, and dropwise add 40-60 parts of ammonium persulfate, 1000-1100 parts of allyl polyethylene glycol, 90-100 parts of methacrylic acid, and 260 parts of initiator under the protection of a protective gas. The four-necked flask can ensure that ammonium persulfate, allyl polyethylene glycol, and methacrylic acid are added simultaneously without affecting each other. All components are added dropwise within 5 minutes. The protective gas selected in this embodiment is nitrogen. After the addition is completed, the reaction is continued for 2 hours. After the reaction, the reaction is cooled, and the pH value is adjusted to 7 with sodium hydroxide to obtain a shrinkage-reducing water-reducing agent finished product;

[0067] Step 4: Prepare CTHP (carboxyl-terminated hyperbranched polyester): Add 13 parts of methylene succinic acid to DMAC solvent, then drop 1 part of p-toluenesulfonic acid, add 30 parts of triethanolamine, and keep at 150°C for 10 hours under a nitrogen atmosphere. The product HTHP (hydroxyl-terminated hyperbranched polyester) obtained by the reaction. After that, take 40 parts of HTHP and 1 part of p-toluenesulfonic acid, weigh 10 parts of trimellitic anhydride, and continue to keep at 150°C for 10 hours under a nitrogen atmosphere. After full reaction, use a rotary evaporator for purification. The product CTHP is obtained.

[0068] Step 5: configuring the multi-component composite system includes: adding 20 parts of a polymerizing agent triethanolamine into a container, adding 950-1000 parts of water to adjust stirring, then adding 9-20 parts of borax, 9-20 parts of sodium gluconate, 5-6 parts of polycarboxylic acid and 9-20 parts of CTHP, using a mixing process simulation algorithm to determine the optimal mixing parameters, and after mixing evenly according to the optimal mixing parameters, a multi-component composite system is obtained, i.e., a special hydration temperature rise inhibitor for large volume concrete.

[0069] Example 2

[0070] In order to evaluate the hydration temperature rise effect, slow setting and strength retention performance of the obtained hydration temperature rise inhibitor, and to evaluate the hydration heat inhibition performance of Example 1, C30 concrete was prepared. In the test, the dosage of Example 1 and the comparative example was fixed at 0.2% of the amount of cementitious material.

[0071] This embodiment adopts the formula shown in Table 1 below: Based on the mass of raw materials, the hydration temperature rise inhibitor formula adopted adopts the composite system obtained by configuring the four monomers in the above step.

[0072] Table 1C30 concrete mix ratio kg / m 3

[0073] cement Fly ash sand stone water Hydration temperature rise suppression admixture 310 77 752 1083 178 0.774

[0074] Example 3

[0075] C30 concrete was prepared. Different from Example 2, the sodium gluconate used was a mixture of sodium gluconate and potassium gluconate.

[0076] Comparative Example 1

[0077] C30 concrete was prepared, and different from the embodiment, a multi-component composite system admixture without CTHP was used.

[0078] Comparative Example 2

[0079] C30 concrete was prepared. Different from Example 2, the triethanolamine used in step 4 was replaced by water of equal mass.

[0080] Comparative Example 3

[0081] C30 concrete was prepared. The difference from Example 2 was that in step 4, 20 parts of a polymerization agent triethanolamine was added to the container, and 950-1000 parts of water were added to adjust the stirring. Then 9-20 parts of borax, 5-6 parts of polycarboxylic acid and 9-20 parts of CTHP were added and stirred evenly to obtain a multi-component composite system without sodium gluconate.

[0082] The adiabatic temperature rise test of concrete is carried out in accordance with the "Standard for Test Methods for Performance of Ordinary Concrete Mixtures" (GB / T50080-2016). The shrinkage performance of concrete is tested with reference to GB-T50082-2009 "Standard for Test Methods for Long-term Performance and Durability of Ordinary Concrete". The net paste fluidity and concrete slump are tested with reference to GB8076-2008 "Concrete Admixtures". The compressive strength of concrete is tested with reference to GB / T50081-2002 "Standard for Test Methods for Mechanical Properties of Ordinary Concrete"; the adiabatic temperature rise and setting time of concrete are tested with reference to GB / T50080-2016 "Standard for Test Methods for Performance of Ordinary Concrete Mixtures". The total cracking area per unit area is detected with reference to the early cracking resistance test method in Part 9 of the "Standard for Test Methods for Long-term Performance and Durability of Ordinary Concrete" (GBT 50082-2009). The test results of the present invention are shown in Table 2 below;

[0083] Table 2 Test results of Examples 2-3 and Comparative Examples 1-3

[0084]

[0085]

[0086] From the test results in Table 2 above, it can be seen that the concrete hydration temperature rise inhibitor of the present invention can effectively reduce the 7d adiabatic temperature rise and total cracking area per unit area of ​​concrete, and is beneficial to the early workability of concrete and the compressive strength of concrete at various ages. It can significantly extend the final setting time of concrete without changing the initial setting time. Thus, it has strong social and economic benefits.

[0087] In summary, with the help of the above technical scheme of the present invention, the present invention provides a concrete hydration temperature rise inhibitor with a simple, efficient and green preparation process, good slow setting characteristics, and no effect on the mechanical properties and durability of concrete. It can overcome the shortcomings of large and concentrated heat release of ordinary concrete, complex traditional construction technology and process, high cost, and poor structural integrity by adopting admixtures to reduce hydration heat and extend final setting time, solve the problem of temperature cracks in large-volume concrete, reduce the complexity of construction, and improve the cracking phenomenon of large-volume concrete, achieving the technical goal of low cost, high efficiency, and high adaptability. In addition, the present invention can accurately predict the particle distribution and flow field characteristics in the mixing process by using a mixing process simulation algorithm, determine the optimal stirring time and speed, thereby effectively improving the mixing uniformity, reducing production energy consumption, and ensuring the high quality and stability of the final product.

[0088] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A hydration temperature rise inhibitor for mass concrete, characterized in that: The invention comprises the following raw materials in parts by weight: 95-105 parts of borax, 50-60 parts of triethanolamine, 90-110 parts of gluconate, 190-200 parts of polycarboxylic acid and 95-105 parts of carboxyl-terminated hyperbranched polyester.

2. The hydration temperature rise inhibitor for mass concrete according to claim 1, characterized in that: The gluconate is composed of any one of sodium gluconate or potassium gluconate or a mixture of the two.

3. A method for preparing a special hydration temperature rise inhibitor for mass concrete, used for preparing the special hydration temperature rise inhibitor for mass concrete as claimed in any one of claims 1 to 2, characterized in that: The preparation method comprises the following steps: S1. Preparation of temperature inhibitor borax: placing the prepared borax stone powder and sulfuric acid in a reaction bottle for sufficient reaction, filtering out the residue to obtain a boric acid solution; heating and evaporating the boric acid solution to obtain a concentrated boric acid solution, and separating and drying the solid after crystallization, and storing it in a container for later use; S2, preparing the polymerization agent triethanolamine: adding ethanolamine to a three-necked flask into which ammonia gas has been introduced in advance, and stirring continuously at room temperature; after stopping the introduction of nitrogen gas, adding ethylene oxide and stirring continuously, maintaining a constant temperature, obtaining the polymerization agent triethanolamine after complete reaction, and cooling the discharged material for purification for standby use; S3, preparing a shrinkage-reducing water-reducing agent polycarboxylic acid: adding water and sodium methacrylic acid to a four-necked flask and heating to a preset temperature; continuing to drop ammonium persulfate, allyl polyethylene glycol, methacrylic acid and an initiator into the four-necked flask under the protection of a protective gas, continuing to react after the dropwise addition is completed, and adjusting the pH value after cooling to obtain a finished shrinkage-reducing water-reducing agent; S4, preparing a carboxyl-terminated hyperbranched polyester: sequentially adding methylene succinic acid, toluenesulfonic acid and triethanolamine to a dimethylacetamide solvent, and reacting for a preset time under a nitrogen atmosphere to obtain a hydroxyl-terminated hyperbranched polyester; continuing to fully react the hydroxyl-terminated hyperbranched polyester, p-toluenesulfonic acid and trimellitic anhydride under a nitrogen atmosphere, and performing purification after the reaction to obtain a carboxyl-terminated hyperbranched polyester; S5. Configure a multi-component composite system: Use a mixing process simulation algorithm to determine the optimal mixing parameters. Based on the optimal mixing parameters, add polymerizer triethanolamine, water, borax, gluconate, polycarboxylic acid and carboxyl hyperbranched polyester into the mixer in sequence for mixing to obtain a special hydration temperature rise inhibitor for large volume concrete.

4. The method for preparing the special hydration temperature rise inhibitor for mass concrete according to claim 3, characterized in that: In step S1, the weight proportion of borax powder is 120-150 parts, and the weight proportion of sulfuric acid is 300 parts.

5. The method for preparing the special hydration temperature rise inhibitor for mass concrete according to claim 3, characterized in that: In step S2, the weight portion of ethanolamine is 150-200 parts, the stirring time at room temperature is 30 minutes, the weight portion of ethylene oxide is 40-60 parts, and the constant temperature is 80°C.

6. The method for preparing the special hydration temperature rise inhibitor for mass concrete according to claim 3, characterized in that: In step S3, the weight of water is 1700 parts, the weight of sodium methacrylate sulfonate is 10-30 parts, the preset temperature is 80°C, the weight of ammonium persulfate is 40-60 parts, the weight of allyl polyethylene glycol is 1000-1100 parts, the weight of methacrylic acid is 90-100 parts, and the weight of the initiator is 560 parts; the addition of all components is completed within 5 minutes, the protective gas is nitrogen, and the reaction is continued for 2 hours after the addition is completed. Sodium hydroxide is used to adjust the pH value, and the pH value is adjusted to 7.

7. The method for preparing the special hydration temperature rise inhibitor for mass concrete according to claim 3, characterized in that: In step S4, the weight proportion of methylene succinic acid is 13 parts, the weight proportion of toluenesulfonic acid is 1 part, the weight proportion of triethanolamine is 30 parts, the preset reaction time under nitrogen atmosphere is 10 hours, the reaction temperature is 150°C, the weight proportion of hydroxyl-terminated hyperbranched polyester is 40 parts, the weight proportion of p-toluenesulfonic acid is 1 part, and the weight proportion of trimellitic anhydride is 10 parts.

8. The method for preparing the special hydration temperature rise inhibitor for mass concrete according to claim 3, characterized in that: Determining the optimal stirring parameters using a mixing process simulation algorithm comprises the following steps: The objective function is constructed with the optimization goals of maximizing mixing uniformity and minimizing energy consumption, and the input parameters are determined as stirring time, stirring speed and material properties; a three-dimensional model of the mixer is constructed, and boundary conditions and material characteristics are set; Determine the initial stirring time and speed range, obtain the initial parameter set, and use the three-dimensional model of the mixer to simulate the flow field, particle distribution and mixing uniformity indicators under the current parameters; Based on the optimization algorithm, the mixing time and speed parameters are updated according to the simulation results, a new parameter set is generated, and the updated uniformity index and energy consumption are calculated using the three-dimensional model of the mixer; When the objective function value changes less than the set threshold or reaches the maximum number of iterations, the optimization is stopped to obtain the optimized optimal stirring time and stirring speed.

9. The method for preparing the special hydration temperature rise inhibitor for mass concrete according to claim 8, characterized in that: The expression of the objective function is: Where F represents the objective function value, λ1 and λ2 represent the mixing uniformity weight and energy consumption weight respectively, σ represents the standard deviation of the concentration of particles or components in the mixture, μ represents the average concentration of particles or components in the mixture, E represents the total energy consumption during the mixing process, and E max represents the rated maximum energy consumption of the mixer, N represents the total number of sample points, x i represents the component concentration at the sample point, T represents the torque applied by the mixer to the fluid, ω represents the rotation speed of the impeller, and t represents the stirring time.

10. The method for preparing the special hydration temperature rise inhibitor for mass concrete according to claim 3, characterized in that: In step S5, the weight proportion of the polymerization agent triethanolamine is 20 parts, the weight proportion of water is 950-1000 parts, the weight proportion of borax is 9-20 parts, the weight proportion of gluconate is 9-20 parts, the weight proportion of polycarboxylic acid is 5-6 parts, and the weight proportion of carboxyl hyperbranched polyester is 9-20 parts.

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