Impact-resistant and wear-resistant mass concrete and its application

Abstract

This invention discloses an impact-resistant and wear-resistant mass concrete and its application, belonging to the field of concrete technology. The impact-resistant and wear-resistant mass concrete provided by this invention includes reinforcing steel and concrete, wherein the concrete mix proportion is: coarse aggregate 1300-1500 kg / m³. 3 Fine aggregate 600-800 kg / m³ 3 Cement 100-200kg / m 3 Mineral admixtures 40-100 kg / m³ 3 Water-reducing agent 1-10 kg / m³ 3 Water 80-150 kg / m 3 The outer surface of the mass concrete is coated with a modified polyurea layer with a thickness of 1-10 mm. The modified polyurea is polymerized from an amino component and an isocyanate prepolymer. The amino component includes fluorinated aminosiloxanes and maleate-substituted triamines in a molar ratio of (1-2):(8-9). By spraying or coating the surface of the mass concrete with modified polyurea, the impact resistance, wear resistance, and impermeability of the mass concrete are improved.

Description

Technical Field

[0001] This invention relates to the field of concrete technology, specifically to a type of impact-resistant and wear-resistant mass concrete and its applications. Background Technology

[0002] Hydraulic spillway structures are water conservancy projects used to discharge floodwaters or waterlogged water from reservoirs, rivers, canals, and flood-prone areas that exceed their storage or handling capacity. They also serve to release water stored in reservoirs and canals for safety protection or inspection and maintenance. Their primary function is to ensure the safety of water conservancy projects and structures, and to mitigate the impact of floods. For hydraulic spillway structures, erosion damage from high-speed, sediment-laden water flow on the flow surface is a common hazard. Nearly 70% of large concrete dams experience erosion damage during operation. This damage leads to the peeling of surface materials and exposure of reinforcement, affecting the normal operation of the spillway structure and, in severe cases, causing catastrophic accidents. Erosion damage not only affects the safe operation of hydraulic spillway structures, but the repeated repairs also consume significant human and financial resources. In recent years, my country has vigorously developed the water resources in the southwest. A number of large-scale water conservancy and hydropower projects have been built or are under construction, including Jinping, Longtan, Xiangjiaba, Xiluodu, Xiaowan, and Wudongde. These projects involve large river drops, high water heads, high water and sediment content, and large discharge per unit width, which puts forward higher requirements for the erosion and abrasion resistance of spillway structures. Therefore, the research on erosion and abrasion resistant materials has always been the focus of research on the erosion and abrasion resistance of hydraulic spillway structures.

[0003] Based on different failure mechanisms, erosion damage can be divided into abrasion damage, cavitation damage, and scour damage. During the operation of spillway structures, multiple forms of damage often occur simultaneously and may even promote each other. Therefore, erosion-resistant materials are required to have excellent comprehensive erosion resistance. Selecting high-performance erosion-resistant materials is of great engineering and economic significance for the safe operation of hydraulic spillway structures. Research on erosion-resistant materials began in the 1960s. In 1968, epoxy concrete and furan concrete were used to repair the bottom slab and apron of the sand flushing gate at the Shimian Hydropower Station. In 1979, polymer impregnation technology was used to strengthen the concrete surface of the Erjiang spillway and other overflow structures of the Gezhouba Dam project, and polymer impregnation was used to repair micro-cracks on the dam surface. In the mid-1990s, polyurea technology was successfully developed in China and applied to several water conservancy projects, including the spiral shell of the Nierji Hydropower Station in Heilongjiang, the Sanjiadian Dam in Beijing, the Heshan Dam in Guangdong, and the Longkou Hydropower Station in Shanxi.

[0004] Polyurea is a high-strength and high-toughness elastomer material, attracting attention due to its resistance to abrasion, aging, corrosion, and impact, as well as its unique workability. In the mid-1990s, Professor Huang Weibo pioneered the successful development of polyurea technology in China, which has been applied in several water conservancy and waterway projects with good results. Polyurea materials exhibit excellent resistance to natural light, freeze-thaw cycles, and temperature fluctuations. Its superelasticity endows the material with excellent crack resistance, effectively inhibiting cracks and crack propagation in concrete dam surfaces. However, the rapid reaction rate of polyurea materials can easily lead to excessively large molecular weights, resulting in poor material flowability and affecting its processability. Furthermore, the application of polyurea materials on the surfaces of hydraulic spillway structures places higher demands on water resistance and abrasion resistance. Summary of the Invention

[0005] To overcome the shortcomings of the existing technology, the present invention provides impact-resistant and wear-resistant mass concrete, wherein modified polyurea is sprayed or coated on the surface of the mass concrete, thereby improving the impact resistance, wear resistance and impermeability of the mass concrete.

[0006] The technical solution for achieving the objective of this invention is as follows:

[0007] A type of impact-resistant and wear-resistant mass concrete, comprising reinforcing steel and concrete, wherein the concrete mix proportion is: coarse aggregate 1300-1500 kg / m³ 3 Fine aggregate 600-800 kg / m³ 3 Cement 100-200kg / m 3 Mineral admixtures 40-100 kg / m³ 3 Water-reducing agent 1-10 kg / m³ 3 Water 80-150 kg / m 3 The outer surface of the large-volume concrete is covered with a modified polyurea with a thickness of 1 to 10 mm. The modified polyurea is polymerized from an amino component and an isocyanate prepolymer. The amino component includes fluorinated aminosiloxane and maleate-substituted triamine in a molar ratio of (1 to 2): (8 to 9).

[0008] Specifically, the structural formula of the fluorinated aminosiloxane is shown in Formula 1, and the general structural formula of the maleate substituted triamine is shown in Formula 2:

[0009]

[0010] Where R1 is

[0011] R2 is at least one of CH3, CH2CH3, CH(CH3)2, and CH2CH2CH2CH3.

[0012] The molar ratio of the amino group of the amino component to the isocyanate group of the isocyanate prepolymer is 100:(101-110).

[0013] In one specific embodiment, the fluorinated aminosiloxane is prepared by reacting 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane and hexafluorobutyl methacrylate in a molar ratio of 1:(2.01-2.1) under a nitrogen atmosphere via a Michael addition reaction.

[0014] In one specific embodiment, the maleate-substituted triamine is prepared by reacting a triamine with a molar ratio of 1:(3.01-3.1) and a maleate through a Michael addition reaction under a nitrogen atmosphere.

[0015] In one specific embodiment, the isocyanate prepolymer is a polymer of diisocyanate and polypropylene oxide, and the isocyanate group content of the isocyanate prepolymer is 12-18 mol.

[0016] Specifically, the polyamine is at least one of tris(2-aminoethyl)amine and melamine.

[0017] The maleic ester is at least one of dimethyl maleate, diethyl maleate, diisopropyl maleate, and dibutyl maleate.

[0018] The diisocyanate is at least one of isophorone diisocyanate, isophthalic diisocyanate, diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, toluene diisocyanate, and hexamethylene diisocyanate.

[0019] In one specific embodiment, the fine aggregate is natural river sand or manufactured sand, and the stone powder content of the natural river sand or manufactured sand is 11-16.6 wt%. Preferably, the stone powder content of the natural river sand or manufactured sand is 12-15 wt%, and more preferably, the stone powder content of the natural river sand or manufactured sand is 13-14 wt%.

[0020] In one specific embodiment, the coarse aggregate is at least one of crushed stone or pebbles, wherein the particle size of the crushed stone or pebbles is 5-80 mm. More preferably, the coarse aggregate is obtained by three-gradation of crushed stone or pebbles with particle sizes of 5-20 mm, 20-40 mm, and 40-80 mm.

[0021] In one specific embodiment, the cement is at least one of ordinary Portland cement, low-heat Portland cement, or medium-heat Portland cement, and the water-cement ratio is 0.34 to 0.46.

[0022] In one specific embodiment, the mineral admixture is at least one of fly ash, mineral powder, silica fume, and metakaolin; preferably, the mineral admixture is fly ash and mineral powder.

[0023] In one specific embodiment, the method for preparing the large-volume concrete includes the following steps:

[0024] (1) Tie the foundation slab and reinforcing bars in the excavated foundation trench, support the concrete pads of the same strength, and install the formwork;

[0025] (2) Put coarse aggregate, fine aggregate, cement and mineral admixture into the mixing plant, mix for 1 to 2 minutes, then add ice water mixture, mix for 2 to 5 minutes, then add water-reducing agent, continue mixing until the ice is fully melted, and the concrete outlet temperature is ≤16℃.

[0026] (3) Concrete is poured into the reinforced formwork in layers by pump truck, with each layer being 30-50cm evenly distributed. Concrete is vibrated by φ50mm immersion manual vibrator until the concrete surface shows cement paste and no longer settles and the surface is basically free of bubbles.

[0027] (4) After the concrete surface is vibrated and leveled, it is covered with plastic film. After hardening, the formwork is removed, the surface is roughened, and then it is cured for at least 28 days.

[0028] (5) The modified polyurea is prepared by mixing the fluorinated aminosiloxane and maleate-substituted triamine with the isocyanate prepolymer on site and stirring for 4 to 6 minutes. Then, the modified polyurea with a thickness of 1 to 10 mm is sprayed on the surface of the dry and clean large-volume concrete and air-dried for at least 24 hours.

[0029] Another objective of this invention is to protect the application of the aforementioned large-volume concrete in locks, hydroelectric power stations, and water-retaining structures.

[0030] Beneficial effects

[0031] This invention provides a mass concrete with impact and wear resistance. By spraying or coating modified polyurea onto the surface of mass concrete, a mass concrete with impact and wear resistance is obtained. The modified polyurea is polymerized from an amino component with amino groups and an isocyanate prepolymer with isocyanate groups. Fluorosilicone groups further improve the hydrophobicity and wear resistance of the polyurea coating. The hyperbranched polymerization method improves the flowability of the polyurea polymer, making it easier to spray. Simultaneously, it allows the solidified modified polyurea to form a cross-linked network structure, improving its mechanical properties. Furthermore, to avoid an overly rapid and violent reaction between the amino and cyanate groups, fluorinated aminosiloxanes with secondary amine structures and maleic esters are used to replace the triamine, and the isocyanate is prepared as a prepolymer. This slows down the curing time after mixing the amino component and the isocyanate prepolymer, meeting the time difference requirements between preparation and spraying completion in actual construction sites. Attached Figure Description

[0032] Figure 1 The 1H NMR spectrum of a fluorinated aminosiloxane;

[0033] Figure 2 The 1H NMR spectrum of diethyl maleate-substituted tris(2-aminoethyl)amine;

[0034] Figure 3 This is a comparison diagram of the impact and abrasion resistance tests of concrete in Example 1 and Comparative Example 7 using the rotating jet method. Detailed Implementation

[0035] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0036] Unless otherwise specified, the experimental methods used in the embodiments are conventional methods, and the materials and reagents used are commercially available unless otherwise specified.

[0037] The raw materials used in the examples and comparative examples are described below:

[0038] Cement: Ordinary Portland cement, PO 42.5R, purchased from China Resources Cement;

[0039] Mineral admixture 1: Mineral powder, S95 mineral powder, purchased from Xiangtan Iron and Steel Co., Ltd. Yangchun New Iron and Steel Co., Ltd.;

[0040] Mineral admixture 2: fly ash, fineness (45um square hole sieve residue) is 21.8%, Guodian Shenneng Huayingshan Power Generation Co., Ltd.;

[0041] Fine aggregate 1: Manufactured sand, with a stone powder content of 9.8 wt%; sourced from Liuzhou City, Guangxi Province;

[0042] Fine aggregate 2: Manufactured sand, with a stone powder content of 13.2 wt%; sourced from Liuzhou City, Guangxi Province;

[0043] Fine aggregate 3: Manufactured sand, with a stone powder content of 16.6 wt%; sourced from Liuzhou City, Guangxi Province;

[0044] Coarse aggregate: Granite crushed stone, produced in Liuzhou, Guangxi, with a three-stage gradation of 5-20mm, 20-40mm, and 40-80mm particle size;

[0045] Water-reducing agent: A series of polycarboxylate high-performance water-reducing agents were purchased from Jiangsu Subote.

[0046] Ice-water mixture: The raw material is tap water, which meets the requirements of the standard "Mixing Water for Concrete" (JGJ 63-2006);

[0047] Hexafluorobutyl methacrylate: 96% purity, purchased from Guangzhou Hewei Pharmaceutical Technology Co., Ltd.

[0048] 1,3-Bis(3-aminopropyl)-1,1,3,3-Tetramethyldisiloxane: 99% purity, purchased from Zhongshan Yuanda New Materials Co., Ltd.;

[0049] Triamine 1: Tris(2-aminoethyl)amine, 97% purity, purchased from Guangzhou Hewei Pharmaceutical Technology Co., Ltd.;

[0050] Triamine 2: Melamine: 99.5% purity, industrial grade, purchased from Guangzhou Haoyu International Trade Co., Ltd.;

[0051] Maleate ester: Diethyl maleate, 99% pure, purchased from Guangzhou Shanghe Chemical Technology Co., Ltd.;

[0052] Diisocyanate: Isophorone diisocyanate, 99% purity, purchased from Guangdong Wengjiang Chemical Reagent Co., Ltd.

[0053] Polypropylene oxide: average molecular weight 1000, catalog number 202320, purchased from Merck Life Sciences;

[0054] Hexamethylenediamine: analytical grade, purchased from Guangdong Wengjiang Chemical Reagent Co., Ltd.;

[0055] HDI trimer: CAS: 3779-63-3, purchased from Guangdong Yunxing Biotechnology Co., Ltd.;

[0056] Polyurea: 9891, purchased from Wanhua Energy Saving Technology (Yantai) Co., Ltd.;

[0057] Unless otherwise specified, all components and raw materials used in the embodiments and comparative examples of this invention are commercially available, and the same type of components and raw materials are used in each parallel experiment.

[0058] Preparation Example

[0059] Preparation Example 1

[0060] Modified polyurea 1: Self-made, preparation method is as follows:

[0061] S1. Preparation of fluorinated aminosilanes: Under a nitrogen atmosphere, 1 mole of 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane was placed in a reactor, and 2.1 moles of hexafluorobutyl methacrylate were added at a dropping rate of 2-3 s / drop while stirring. The temperature was raised to 40°C, and the reaction was carried out at 40°C with stirring for 15 hours. The mixture was then filtered under reduced pressure to obtain fluorinated aminosilanes. The structural formula of the fluorinated aminosilane is shown in Formula 1, and its 1H NMR spectrum is shown in Formula 1. Figure 1 As shown, the solvent is CDCl3;

[0062]

[0063] S2. Preparation of maleate-substituted triamine: Under a nitrogen atmosphere, 1 mole of tris(2-aminoethyl)amine was placed in a reactor and heated to 40°C. 3.1 moles of diethyl maleate were added with stirring at a dropping rate of 2–3 s / drop. The temperature was raised to 60°C, and the reaction was stirred at 60°C for 36 hours. The mixture was then filtered under reduced pressure to obtain the maleate-substituted triamine. The structural formula of the maleate-substituted triamine is as follows:

[0064] As shown in Equation 2, the 1H NMR spectrum is as follows: Figure 2 As shown, the solvent is CDCl3;

[0065]

[0066] S3. Preparation of isocyanate prepolymer: Under a nitrogen atmosphere, 100 parts by weight of isophorone diisocyanate were added to a reactor, the temperature was raised to 50°C, and 100 parts by weight of polypropylene oxide were added dropwise while stirring. After the addition was completed, the temperature was raised to 75-80°C. Samples were taken every hour, and the isocyanate content was determined by the di-n-butylamine method. When the isocyanate content in the prepolymer was close to 15%, the reaction was terminated, and the isocyanate prepolymer was obtained.

[0067] S4. Before use, mix fluorinated aminosilane and maleate-substituted triamine in a molar ratio of 2:8 to obtain an amino component. Before use, mix it with the isocyanate prepolymer obtained in step S3 in a molar ratio of 100:105 for amino and isocyanate groups. After stirring for 4 minutes, a modified polyurea is obtained. Spray it onto the surface of a large volume concrete and allow it to cure naturally for 24 hours.

[0068] It should be noted that the amino component and isocyanate prepolymer are packaged in the pre-mixed ratio during on-site construction, and no further weighing is required on-site; they can be directly mixed and used.

[0069] Preparation Example 2

[0070] Modified polyurea 2: The preparation method is different from that of modified polyurea 1, in that the molar ratio of fluorinated aminosilane and maleate ester-substituted triamine is 1:9;

[0071] Preparation Example 3

[0072] Modified polyurea 3: The preparation method is the same as that of modified polyurea 1, except that the tris(2-aminoethyl)amine in step S2 is replaced with melamine;

[0073] Preparation Example 4

[0074] Modified polyurea 4: The preparation method is different from that of modified polyurea 1, in that the molar ratio of fluorinated aminosilane and maleate ester-substituted triamine is 3:7;

[0075] Preparation Example 5

[0076] Modified polyurea 5: The preparation method is different from that of modified polyurea 1 in that the triamine is not replaced by maleate ester, but is used directly;

[0077] Preparation Example 6

[0078] Modified polyurea 6: The preparation method is the same as that of modified polyurea 1, except that the isocyanate prepolymer is replaced with HDI trimer;

[0079] Preparation Example 7

[0080] Modified polyurea 7: The preparation method is the same as that of modified polyurea 1, except that the tris(2-aminoethyl)amine in step S2 is replaced with hexamethylenediamine;

[0081] Preparation Example 8

[0082] Modified polyurea 8: The preparation method is different from that of modified polyurea 1 in that fluorinated aminosilanes are not added;

[0083] The modified polyurea was subjected to the following performance tests, and the results are shown in Table 1:

[0084] (1) Coagulation time determination: Under room temperature conditions, the amino component and isocyanate prepolymer of Preparation Examples 1 to 8 were mixed and the mixture was stirred rapidly. At the same time, a stopwatch was started to time the time until the mixture stopped flowing. The coagulation time is the time taken.

[0085] (2) Contact angle test: Prepared Examples 1 to 8 were mixed at room temperature and stirred continuously until uniform. The mixture was then coated onto a glass slide and allowed to solidify. After curing at room temperature for 7 days, water was used as the test liquid to test the contact angle data of the modified polyurea to water. Three sets of data were measured for each sample and the average value was calculated.

[0086] (3) Wear resistance test: Test conditions: 500g load and 500r rotation. Before the preparation examples 1 to 8 are fully cured, they are coated on iron sheets with the same length and width. After curing and drying, they are cured for 7 days. Before the test, they are weighed by an analytical balance with an accuracy of 0.1mg. Then they are tested on a JM-Ⅳ type wear tester. After the test, the mass after the test is weighed on an analytical balance. The difference in mass before and after the test is the wear mass of the modified polyurea. The average value of three sets of data for each modified polyurea is calculated.

[0087] Table 1. Performance test results of modified polyurea in Preparation Examples 1-8

[0088]

[0089]

[0090] The test results from preparation examples 1, 2, 4, and 8 show that the introduction of fluorinated branches and maleic esters not only improves the hydrophobicity and abrasion resistance of the polyurea coating, but also increases the steric hindrance between the amino group and the isocyanate, reduces its reactivity, and greatly prolongs the coagulation time of the polyurea, thus meeting the needs of actual construction.

[0091] The test results from Preparation Examples 1, 5, and 6 show that when directly polymerizing triamines with isocyanates, the high reactivity of the primary amine means that even with the use of isocyanate prepolymers to reduce the isocyanate group content, the reaction rate between the triamine and isocyanate remains relatively fast, resulting in demanding application conditions. While using isocyanate trimers instead of isocyanate prepolymers can also produce hyperbranched polyurea materials, the high isocyanate concentration leads to a shorter coagulation time and higher viscosity of the reaction system, resulting in poor appearance and physicochemical properties of the prepared polyurea coating.

[0092] The test results from Preparation Example 1 and Preparation Example 7 show that the hydrophobicity and wear resistance of linear polyurea are not as good as those of hyperbranched polyurea materials with cross-linked network structures.

[0093] Examples and Comparative Examples

[0094] A type of impact-resistant and wear-resistant large-volume concrete refers to a thin-walled, high aspect ratio, and wide-section structure in a key engineering project. In a specific embodiment, the dimensions of the floodgate bottom plate are 35m×16.5m×2.6m, the gate pier casting block is 35m×1.75m×3m, the power plant floor plate is 42m×29m×2.6m, the lock chamber wall bottom plate is 32.8m×21.4m×1.5m, and the upper gate head bottom plate is 40m×23.5m×1.5m. The specific dimensions can be adjusted according to the project situation or construction needs.

[0095] In one specific embodiment, the large-volume concrete is a laboratory specimen, specifically a concrete structure with dimensions of 1m × 1m × 1m.

[0096] In one specific embodiment, the method for preparing the large-volume concrete includes the following steps:

[0097] In the excavated foundation trench, the foundation slab and reinforcing bars are tied, concrete blocks of the same strength are supported, and the formwork is installed.

[0098] Add coarse aggregate, fine aggregate, cement, and mineral admixtures to the mixing plant and mix for 1-2 minutes. Then add ice-water mixture and mix for 2-5 minutes. Add water-reducing agent and continue mixing until the ice is fully melted. The concrete outlet temperature should be ≤16℃.

[0099] Concrete is poured into the reinforced formwork in layers using a pump truck, with each layer being 30-50cm evenly distributed. Concrete is vibrated manually using a φ50mm immersion vibrator until the concrete surface shows cement paste and no longer settles and the surface is basically free of bubbles.

[0100] After vibration and leveling, the concrete surface is covered with plastic film. After hardening, the formwork is removed, the surface is roughened, and standard curing is performed for at least 28 days. Before spraying, loose parts of the surface are removed to expose a solid base layer that is free of moisture and standing water.

[0101] Modified polyurea is prepared by mixing the amino component with the isocyanate prepolymer on site and stirring for 4-6 minutes. Then, a 5mm thick layer of modified polyurea is sprayed onto the surface of a dry and clean large-volume concrete and air-dried for at least 24 hours.

[0102] The specific composition and mix proportions of the concrete are shown in Table 2.

[0103] Table 2. Specific composition and mix proportions of mass concrete (unit: kg / m³) 3 )

[0104]

[0105]

[0106] Performance testing

[0107] The following tests were performed on the concrete, and the results are shown in Table 3.

[0108] (1) Wear rate and 28d impact abrasion strength test: The wear rate and 28d impact abrasion strength of concrete were tested according to “4.20 Rotating jet method concrete impact abrasion test” in DL / T 5150—2017 “Test Procedure for Hydraulic Concrete”.

[0109] (2) 28d compressive strength: The compressive strength of concrete cubes was tested in accordance with "4.2 Compressive strength test of concrete cubes" in DL / T 5150—2017 "Test Procedure for Hydraulic Concrete";

[0110] (3) 28d flexural strength: The flexural strength at 28d was tested in accordance with “4.6 Concrete flexural test” of DL / T 5150—2017 “Test Procedure for Hydraulic Concrete”.

[0111] (4) Permeability grade test: The permeability grade of concrete shall be tested in accordance with “4.24 Permeability Test of Concrete” of DL / T 5150—2017 “Test Procedure for Hydraulic Concrete”;

[0112] Table 3 Performance Tests of Mass Concrete and its Surface Coatings

[0113]

[0114]

[0115] As can be seen from the examples and comparative examples, the impact and abrasion resistance, flexural strength and impermeability of the large-volume concrete coated with modified polyurea are significantly improved, but the compressive strength is slightly reduced.

[0116] The performance test results of Examples 1, 5 and Comparative Example 1 show that the proportion of fluorinated aminosiloxane is 10-20 mol% which contributes the best to the impact and wear resistance. When the content of fluorinated aminosiloxane is increased to 30 mol%, due to the incompatibility between fluorinated silicone and polyurea, phase separation is easily formed, which will lead to a decrease in the mechanical properties of modified polyurea.

[0117] As can be seen from Examples 1, 6, and 7, the modified polyurea coating has the best overall impact and wear resistance, compressive strength, and flexural strength when the coating thickness is 4–6 mm. When the coating thickness is higher, although the flexural strength is improved, the loss of compressive strength is also more significant.

[0118] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A shock- and wear-resistant mass concrete, characterized in that The reinforced concrete comprises steel bars and concrete, wherein the concrete has a mixing ratio of: coarse aggregate 1300-1500 kg / m 3 , fine aggregate 600-800 kg / m 3 , cement 100-200 kg / m 3 , mineral admixture 40-100 kg / m 3 , water reducing agent 1-10 kg / m 3 , water 80-150 kg / m 3 ; the outer surface of the mass concrete is covered with modified polyurea with a thickness of 1-10 mm, wherein the modified polyurea is polymerized from amino component and isocyanate prepolymer, the amino component comprises fluorine-containing amino siloxane and maleate substituted triamine with a molar ratio of (1-2):(8-9), and the fluorine-containing amino siloxane is prepared by a Michael addition reaction of 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane and hexafluorobutyl methacrylate with a molar ratio of 1:(2.01-2.1) under a nitrogen atmosphere.

2. Mass concrete according to claim 1, characterized in that The structural formula of the fluorine-containing aminosiloxane is shown as formula 1, and the structural general formula of the maleate-substituted triamine is shown as formula 2. Formula 1; Formula 2, wherein R1is or , R2 is at least one of CH3, CH2CH3, CH(CH3)2 and CH2CH2CH2CH3.

3. Mass concrete according to claim 1, characterized in that The maleate-substituted triamine is prepared by a Michael addition reaction of a triamine and a maleate ester in a molar ratio of 1: (3.01-3.1) under a nitrogen atmosphere; the isocyanate prepolymer is a polymer of a diisocyanate and a polypropylene oxide, and the isocyanate content of the isocyanate prepolymer is 12-18 mol%.

4. Mass concrete according to claim 3, characterized in that The triamine is at least one of tris (2-aminoethyl) amine and melamine; the maleate ester is at least one of dimethyl maleate, diethyl maleate, diisopropyl maleate and dibutyl maleate; and the diisocyanate is at least one of isophorone diisocyanate, m-xylylene diisocyanate, diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, toluene diisocyanate and hexamethylene diisocyanate.

5. Mass concrete according to claim 1, characterized in that The fine aggregate is natural river sand or machine-made sand; the coarse aggregate is broken stone or pebble; the cement is ordinary Portland cement, low-heat Portland cement or medium-heat Portland cement; and the mineral admixture is at least one of fly ash, mineral powder, silica fume and metakaolin.

6. Mass concrete according to claim 5, characterized in that The stone powder content of the natural river sand or machine-made sand is 11-16.6 wt%; the particle size of the broken stone or pebble is 5-80 mm; and the mineral admixture is fly ash and mineral powder.

7. Mass concrete according to claim 1, characterized in that The water-binder ratio is 0.34-0.

46.

8. Use of the mass concrete according to any one of claims 1-7 in ship locks, hydropower stations and water retaining and releasing structures.

Images