A high-interfacial-activity in-situ self-assembly tough cement-based pavement material and its preparation method

Abstract

The present invention discloses a high-interfacial-activity in-situ self-assembly tough cement-based pavement material and a preparation method thereof. The pavement material comprises the following raw materials in parts by weight: 20 to 60 parts of a cementitious material containing silicate cement, 0.2 to 0.5 parts of a hydrogel accelerator, and 1 to 7 parts of a hydrogel initiating solution, wherein the hydrogel initiating solution comprises 1 to 5 parts of poly (N-isopropylacrylamide), 0.3 to 1.5 parts of sodium acrylate, 0.03 to 0.12 parts of a cross-linking agent, 0.03 to 0.12 parts of an initiator, and 20 to 60 parts of water; the chemical structure of the hydrogel accelerator is shown in formula (1). After being compounded with the cement-based material, the high-interfacial-activity hydrogel of the present invention can effectively consume the calcium hydroxide produced by cement hydration, greatly enhancing the interfacial bonding strength between the hydrogel and the cement matrix, and improving the service life of the prepared pavement material.

Description

Technical Field

[0001] The invention relates to a high-interfacial-activity in-situ self-assembly tough cement-based pavement material and a preparation method thereof, belonging to the technical field of cement-based pavement materials. Background Art

[0002] In order to promote national fitness and exercise, many places have built a large number of sports parks, fitness trails and other places for people to exercise and keep fit on a daily basis. In order to improve the comfort of walking on pedestrian walkways, cushion the impact and reduce joint injuries, parks and public fitness venues mostly use elastic materials for pavement. Flexible asphalt pavement materials are widely used for pavement in parks and public fitness venues due to their high flexibility and good pedestrian comfort. However, with the development of society and the increasing requirements for environmental protection during urban construction, the shortcomings of flexible asphalt pavement materials have gradually become prominent. These mainly include poor aging resistance, the need for high-temperature paving during construction that produces a large amount of carbon emissions, and the generation of polluting gases and dust during construction, which are not in line with the concept of sustainable development of modern cities and the development requirements of environmental protection in urban construction.

[0003] Hydrogel-cement composite materials have the advantages of high toughness, low construction technology requirements, and a green and environmentally friendly construction process, and they also have certain compressive strength. However, traditional hydrogel-cement materials have the obvious problem of weak interfacial bonding between the hydrogel and cement. This is because the bonding between traditional hydrogels and cement matrices relies on the hydration products formed by the cement components on the surface of the hydrogel. However, since the hydration products contain a large amount of calcium hydroxide, which lacks stability and has low strength, the bonding force at the cement-hydrogel interface is relatively weak. When subjected to impact loads, it is very easy to cause interfacial peeling between the hydrogel and cement, leading to structural damage. Therefore, when using traditional hydrogel-cement composite materials to make pavements, there are shortcomings such as short lifespan, frequent maintenance requirements, and high maintenance costs, which limit the promotion and application of this material. Summary of the Invention

[0004] Objectives of the Invention: The first objective of the present invention is to provide a highly surface-active, in-situ self-assembled, toughened cement-based pavement material. The second objective of the present invention is to provide a method for preparing such a highly surface-active, in-situ self-assembled, toughened cement-based pavement material. When combined with a cement-based material, this highly surface-active hydrogel effectively consumes the calcium hydroxide produced by cement hydration, significantly enhancing the interfacial bonding between the hydrogel and the cement matrix and increasing the service life of the prepared pavement material.

[0005] Technical solution: The high-surface-activity in-situ self-assembly tough cement-based pavement material of the present invention is characterized in that the pavement material comprises the following raw materials in parts by weight: 20 to 60 parts of a cementitious material containing silicate cement, 0.2 to 0.5 parts of a hydrogel accelerator, and 1 to 7 parts of a hydrogel initiating solution, wherein the hydrogel initiating solution comprises 1 to 5 parts of poly (N-isopropylacrylamide), 0.3 to 1.5 parts of sodium acrylate, 0.03 to 0.12 parts of a cross-linking agent, 0.03 to 0.12 parts of an initiator, and 20 to 60 parts of water; the chemical structure of the hydrogel accelerator is shown in formula (1):

[0006]

[0007] Furthermore, the preparation method of the hydrogel accelerator comprises the following steps:

[0008] (1) Tetramethylenediamine (TEMED) is placed in an alkaline solution for surface treatment, adjusted to neutrality, a silane coupling agent is added, and heated for reaction to obtain a system containing the intermediate (TK);

[0009] (2) adding lithium aluminosilicate (LiAlSiO4) to the system containing the intermediate obtained in step (1) and heating the system for reaction to obtain a hydrogel promoter (TL).

[0010] Furthermore, in step (1), the alkali solution includes at least one of sodium hydroxide solution, potassium hydroxide solution, etc.

[0011] Furthermore, in step (1), the concentration of the alkali solution is 0.03 to 0.25 mol / L.

[0012] Furthermore, in step (1), the alkaline solution only needs to be able to completely immerse the TEMED, and the alkaline solution increases the reactive sites on the surface of the TEMED.

[0013] Furthermore, in step (1), an acidic substance is used to adjust the solution to neutrality, and the acidic substance includes at least one of nitric acid, sulfuric acid, etc.

[0014] Furthermore, in step (1), the silane coupling agent includes γ-methacryloxypropyltrimethoxysilane (KH-570) and the like.

[0015] Furthermore, in step (1), the mass ratio of tetramethylenediamine to silane coupling agent is 0.1-0.3:0.03-0.08.

[0016] Furthermore, in step (1), the temperature of the heating reaction is 40 to 80°C, and the heating reaction time is 0.5 to 3.5 hours. Preferably, continuous stirring is performed during the reaction. In this process, the siloxane of the silane coupling agent (taking KH-570 as an example) forms a highly active complex containing silanol groups with water and the amino-alkyl groups on the surface of TEMED for subsequent Li + The grafting reaction process is shown in formula (2):

[0017]

[0018] Furthermore, in step (1), continuous stirring is performed during the reaction.

[0019] Furthermore, in step (2), the mass ratio of tetramethylenediamine to lithium aluminosilicate is 0.1-0.3:0.08-0.2.

[0020] Furthermore, in step (2), the temperature of the heating reaction is 50-95°C and the heating reaction time is 1.5-5.5h. Preferably, continuous stirring is performed during the reaction. In this process, the Al provided by the LiAlSiO4 3+ 、Li + The grafting is achieved by forming a coordination bond with the exposed silanol group on the intermediate (TK). The reaction process is shown in formula (3):

[0021]

[0022] Furthermore, in step (2), continuous stirring is performed during the reaction process.

[0023] Furthermore, the cementitious material containing silicate cement includes at least one of ordinary silicate cement, PI silicate cement, PI silicate cement, slag silicate cement or sulfate-resistant silicate cement.

[0024] Furthermore, the initiator includes at least one of potassium persulfate, ammonium persulfate, sodium persulfate, etc.

[0025] Furthermore, the cross-linking agent includes at least one of N,N-methylenebisacrylamide, N,N'-methylenebisacrylamide, and the like.

[0026] The method for preparing the in-situ self-assembly tough cement-based pavement material with high interfacial activity of the present invention comprises the following steps: adding a gelling material containing silicate cement and a hydrogel initiating solution to a hydrogel accelerator and mixing them evenly to obtain the material.

[0027] Furthermore, when using the high-interface-activity in-situ self-assembled strong-tough cement-based pavement material, the high-interface-activity in-situ self-assembled strong-tough cement-based pavement material is formed into a pavement and then waited for solidification and hardening.

[0028] The present invention provides a high-interfacial-activity in-situ self-assembled tough cement-based pavement material and a preparation method thereof. After the high-interfacial-activity hydrogel is compounded with the cement-based material, it can effectively consume the calcium hydroxide produced by cement hydration, greatly enhancing the interfacial bonding strength between the hydrogel and the cement matrix, and improving the service life of the prepared pavement material.

[0029] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages:

[0030] The present invention first prepares tetramethylenediamine containing aluminosilicate as a hydrogel accelerator, and utilizes the highly active amino groups contained in the tetramethylenediamine in the accelerator to achieve LiAlSiO4 grafting, thereby more accurately strengthening the interfacial bonding between the hydrogel and cement, overcoming the disadvantage of weak bonding between traditional hydrogels and cement matrices. When the hydrogel accelerator is used to mix the hydrogel and cement to form a highly interfacially active hydrogel-cement flexible composite material, the highly active hydrogel surface contains active silica and aluminum ions, so that the calcium ions released by cement hydration combine with the silica and aluminum ions on the hydrogel surface to form CSH gel and ettringite (AFt). As a result, a large amount of stable and high-strength hydration products are formed at the interface between the cement and the hydrogel, while consuming the low-strength hydration product calcium hydroxide, greatly enhancing the interfacial bonding, thereby increasing the impact absorption percentage of the material surface, having an extremely long service life, and requiring no post-maintenance. At the same time, lithium ions have a small ionic radius, high charge density, and interact with cement hydration products, as well as a possible catalytic effect. Therefore, the lithium ions on the hydrogel accelerator can reduce the electric potential barrier on the C3S surface in cement, thereby promoting the binding of water molecules to C3S, accelerating the hydration process of C3S, and generating more CSH gel and Ca(OH)2, thereby promoting a rapid increase in strength at the organic-inorganic interface. This matches the high reaction rate of cement hydration with the rapid gelation of hydrogel, forming a composite material with stronger interfacial bonding. The present invention introduces hydrogel into cement-based pavement materials, which have many advantages over existing asphalt or organic pavement materials, such as being green, low-carbon, environmentally friendly, and having a low overall cost. The resulting new pavement material also meets standard requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is the infrared spectrum of the hydrogel accelerator prepared in Example 1;

[0032] Figure 2 This is a sample of the in-situ self-assembled, tough cement-based pavement material with high interfacial activity prepared in Example 1;

[0033] Figure 3 This is a scanning electron microscope image of a sample of a highly interfacially active in-situ self-assembled tough cement-based pavement material prepared in Example 1. DETAILED DESCRIPTION

[0034] The technical solution of the present invention will be further described below with reference to the accompanying drawings.

[0035] These examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention. The experimental methods in the following examples, where no specific conditions are specified, are generally carried out under conventional conditions or conditions recommended by the manufacturers.

[0036] Unless otherwise defined, all professional and scientific terms used in the present invention have the same meaning as those familiar to those skilled in the art. The reagents or raw materials used in the present invention can be purchased through conventional channels. Unless otherwise specified, the reagents or raw materials used in the present invention are used in a conventional manner in the art or according to the product instructions. In addition, any method and material similar to or equivalent to the described content can be applied to the inventive method. Now, the technical solution of the present invention is further described in conjunction with the accompanying drawings and specific examples.

[0037] Example 1

[0038] 1. Preparation of hydrogel accelerator

[0039] (1) Tetramethylenediamine was completely placed in a 0.15 mol / L sodium hydroxide solution for surface treatment for 16 hours. After completion, the system was adjusted to neutrality with 0.1 mol / L nitric acid. Then, a 3% by mass silane coupling agent (KH-570) aqueous solution was added according to a mass ratio of 0.3:0.03 of the tetramethylenediamine to the silane coupling agent. The mixture was then heated to 60°C and stirred continuously at a speed of 200 r / min for 1.5 hours at the same temperature. After completion, a system containing the intermediate (TK) was obtained and set aside.

[0040] (2) Add lithium aluminosilicate (LiAlSiO4) to the system containing the intermediate (TK) in step (1) at a mass ratio of 0.2:0.18. Then heat to 70°C and stir continuously at 500 r / min for 3 hours at this temperature to obtain a hydrogel promoter (TL).

[0041] The obtained hydrogel promoter was subjected to infrared spectrum analysis, and its infrared spectrum was as shown in FIG. Figure 1 As shown. Figure 1 It can be seen that new infrared characteristic peaks that do not exist in the original polymer are generated, namely the NH peak, Si-O-Li peak and Si-O-Al peak, which clearly indicates the generation of the key characteristic peaks of the hydrogel promoter.

[0042] From the above analysis, it can be seen that the structure of the hydrogel promoter is shown in formula (1):

[0043]

[0044] 2. Preparation of high-surface-active in-situ self-assembled tough cement-based pavement materials

[0045] (S1) Preparation of a hydrogel initiating solution: 2.5 parts by weight of poly (N-isopropylacrylamide) (NIPAm), 0.75 parts by weight of sodium acrylate (SA), 0.075 parts by weight of N,N-methylenebisacrylamide, 0.075 parts by weight of potassium persulfate, and 40 parts by weight of water are mixed and stirred to obtain a hydrogel initiating solution for later use.

[0046] (S2) Take the following raw materials in the following proportions: 45 parts by weight of 42.5 parts of ordinary Portland cement, 0.3 parts by weight of the hydrogel accelerator (TL) prepared in step 1 of this embodiment, and 45 parts by weight of the hydrogel initiating solution prepared in step (S1).

[0047] (S3) The 42.5% ordinary Portland cement and the hydrogel initiating solution from step (S2) are added to the hydrogel accelerator (TL), and the mixture is continuously stirred at 1200 rpm for 3 minutes to obtain a cement-based pavement material. The mixture is then allowed to stand for 10 minutes, and various properties of the pavement material are tested after solidification and hardening.

[0048] Among them: the elongation at break is measured according to the standard of GB / T 23445-2009 "Polymer cement waterproof coating", the bonding strength is measured according to the standard of JC / T 2381-2016 "Repair mortar", the impact absorption is measured according to the standard of GB 36246-2018 "Synthetic material surface sports fields for primary and secondary school students", and the tensile strength retention rate after 240 hours of ultraviolet treatment is measured according to the standard of GB / T23445-2009 "Polymer cement waterproof coating". The test results of the above indicators are shown in Table 1 below.

[0049] Table 1 Performance results of pavement materials in Example 1

[0050] Test indicators Elongation at break / % Bond strength / MPa Shock absorption / % Tensile strength retention / % Test results 72.3 1.76 49.8 98.2

[0051] As shown in Table 1, while impact absorption fully meets standard requirements, aging resistance is significantly improved. After 240 hours of UV treatment, the tensile strength retention rate reaches 98.2%, and the bond strength exceeds the maximum value (1 MPa) required by the standard by 76%, demonstrating the excellent performance of this material. Furthermore, this material is a green, environmentally friendly, non-toxic, and harmless organic and inorganic composite material. Compared to other flexible walkway materials on the market, the combined costs of construction, materials, and maintenance are reduced by over 200%.

[0052] in addition, Figure 2 This is a sample of the pavement material prepared in this embodiment after solidification and hardening. Figure 2 It can be seen that it has excellent flexibility.

[0053] Figure 3 This is a scanning electron microscope (SEM) image of the road surface material prepared in this embodiment. Figure 3 It can be seen that the interface between the cement matrix and the hydrogel contains a large amount of high-strength cement hydration products CSH gel and ettringite (Aft), which makes the interface between the two have good bonding strength.

[0054] Example 2

[0055] 1. Preparation of hydrogel accelerator

[0056] (1) Tetramethylenediamine was completely placed in a 0.25 mol / L sodium hydroxide solution for surface treatment for 12 hours. After completion, the system was adjusted to neutrality with 0.1 mol / L nitric acid. Then, a 3% by mass silane coupling agent (KH-570) aqueous solution was added according to a mass ratio of 0.15:0.06 of the tetramethylenediamine to the silane coupling agent. The mixture was then heated to 80°C and stirred continuously at a speed of 200 r / min for 0.5 hours at the same temperature. After completion, a system containing the intermediate (TK) was obtained and set aside.

[0057] (2) Lithium aluminosilicate (LiAlSiO4) was added to the system containing the intermediate (TK) in step (1) at a mass ratio of 0.3:0.2. The mixture was then heated to 50°C and stirred continuously at 500 rpm for 5.5 hours. After completion, a hydrogel promoter (TL) was obtained.

[0058] 2. Preparation of high-surface-active in-situ self-assembled tough cement-based pavement materials

[0059] (S1) Preparation of a hydrogel initiating solution: 1 part by weight of poly (N-isopropylacrylamide) (NIPAm), 0.3 parts by weight of sodium acrylate (SA), 0.03 parts by weight of N,N-methylenebisacrylamide, 0.03 parts by weight of sodium persulfate, and 20 parts by weight of water. Mix these components and stir until uniformly distributed to obtain a hydrogel initiating solution, which is then set aside.

[0060] (S2) Take the following raw materials in the following proportions: 20 parts by weight of 42.5 ordinary Portland cement, 0.2 parts by weight of the hydrogel accelerator (TL) prepared in step 1 of this embodiment, and 20 parts by weight of the hydrogel initiating solution prepared in step (S1).

[0061] (S3) The 42.5% ordinary Portland cement and hydrogel initiating solution from step (S2) were added to the hydrogel accelerator (TL), followed by continuous stirring at 1200 rpm for 3 minutes to obtain a cement-based pavement material. The material was then allowed to stand for 10 minutes, and after solidification and hardening, its various properties were tested using the same testing methods as in Example 1. The results are shown in Table 2 below.

[0062] Table 2 Performance results of pavement materials in Example 2

[0063]

[0064] Example 3

[0065] 1. Preparation of hydrogel accelerator

[0066] (1) The tetramethylenediamine was completely placed in a 0.03 mol / L sodium hydroxide solution for surface treatment for 8 hours. After completion, the system was adjusted to neutrality with 0.1 mol / L sulfuric acid. Then, a 3% mass fraction of a silane coupling agent (KH-570) aqueous solution was added according to the mass ratio of the tetramethylenediamine to the silane coupling agent of 0.1:0.08. Then, the mixture was heated to 40°C and stirred continuously at a speed of 200 r / min for 3.5 hours at the same temperature. After completion, a system containing the intermediate (TK) was obtained and set aside.

[0067] (2) Add lithium aluminosilicate (LiAlSiO4) to the system containing the intermediate (TK) in step (1) at a mass ratio of 0.1:0.08. Then heat to 95°C and stir continuously at 500 r / min for 1.5 hours at the same temperature to obtain a hydrogel promoter (TL).

[0068] 2. Preparation of high-surface-active in-situ self-assembled tough cement-based pavement materials

[0069] (S1) Preparation of a hydrogel initiating solution: 5 parts by weight of poly (N-isopropylacrylamide) (NIPAm), 1.5 parts by weight of sodium acrylate (SA), 0.12 parts by weight of N,N'-methylenebisacrylamide, 0.12 parts by weight of ammonium persulfate, and 60 parts by weight of water. Mix these components and stir until uniformly distributed to obtain a hydrogel initiating solution, which is then set aside.

[0070] (S2) Take the following raw materials in the following proportions: 60 parts by weight of 42.5 ordinary Portland cement, 0.5 parts by weight of the hydrogel accelerator (TL) prepared in step 1 of this embodiment, and 60 parts by weight of the hydrogel initiating solution prepared in step (S1).

[0071] (S3) The 42.5% ordinary Portland cement and hydrogel initiating solution from step (S2) were added to the hydrogel accelerator (TL), followed by continuous stirring at 1200 rpm for 3 minutes to obtain a cement-based pavement material. The material was then allowed to stand for 10 minutes, and after solidification and hardening, its various properties were tested using the same testing methods as in Example 1. The results are shown in Table 3 below.

[0072] Table 3 Performance results of pavement materials in Example 3

[0073]

[0074] Comparative Example 1

[0075] The preparation process is the same as that of Example 1, except that step (2) of step 1 is omitted, and the system with the intermediate (TK) prepared in Example 1 is used instead of the final hydrogel accelerator to directly prepare the cement-based pavement material, as follows:

[0076] (S1) Take the following raw materials in the following proportions: 45 parts by weight of 42.5 parts of ordinary Portland cement, 0.3 parts by weight of the system containing the intermediate (TK) prepared in step 1 of the above Example 1, and 45 parts by weight of the hydrogel initiating solution prepared in the above Example 1.

[0077] (S2) The 42.5% ordinary Portland cement and hydrogel initiating solution from step (S1) were added to the system containing the intermediate (TK), followed by continuous stirring at 1200 rpm for 3 minutes to produce a cement-based pavement material. The pavement material was then allowed to stand for 10 minutes, and after solidification and hardening, its various properties were tested using the same testing methods as in Example 1. The results are shown in Table 4 below.

[0078] Table 4 Comparative Example 1 Pavement Material Performance Results

[0079]

[0080] Comparative Example 2

[0081] The preparation process is the same as that of Example 2, except that step (2) of step 1 is omitted, and the system containing the intermediate (TK) prepared in Example 2 and lithium aluminosilicate are directly added as raw materials instead of the hydrogel accelerator to prepare the cement-based pavement material, specifically as follows: (S1) Take the following raw materials in the following proportions: 20 parts by weight of 42.5 ordinary Portland cement, 0.12 parts by weight of the system containing the intermediate (TK) prepared in step 1 of the above Example 2, 0.08 parts by weight of lithium aluminosilicate (LiAlSiO4), and 20 parts by weight of the hydrogel initiating solution prepared in the above Example 2.

[0082] (S2) The 42.5% ordinary Portland cement and the hydrogel initiating solution described in step (S1) were added to the system containing the intermediate (TK), followed by the addition of the lithium aluminosilicate. The mixture was then stirred continuously at 1200 rpm for 3 minutes to obtain a cement-based pavement material. The pavement material was then allowed to stand for 10 minutes, and after solidification and hardening, its various properties were tested using the same testing methods as in Example 1. The results are shown in Table 5 below.

[0083] Table 5 Comparative Example 2 pavement material performance results

[0084]

[0085] Comparative Example 3

[0086] The preparation process is the same as that of Example 3, except that no silane coupling agent is used, and the hydrogel accelerator is directly prepared, as follows:

[0087] 1. Preparation of hydrogel accelerator

[0088] (1) Tetramethylenediamine was completely placed in a 0.03 mol / L sodium hydroxide solution for surface treatment. After completion, the system was adjusted to neutrality with 0.1 mol / L sulfuric acid, and then heated to 40 ° C. and stirred continuously at 200 r / min for 3.5 hours at this temperature. After completion, a system containing the intermediate was obtained and set aside.

[0089] (2) Add lithium aluminosilicate (LiAlSiO4) to the system containing the intermediate in step (1) at a mass ratio of 0.1:0.08. Then heat to 95°C and stir continuously at 500 r / min for 1.5 hours at this temperature to obtain a hydrogel accelerator.

[0090] (S3) The 42.5% ordinary Portland cement and hydrogel initiating solution from step (S2) were added to the hydrogel accelerator (TL), followed by continuous stirring at 1200 rpm for 3 minutes to obtain a cement-based pavement material. The material was then allowed to stand for 10 minutes, and after solidification and hardening, its various properties were tested using the same testing methods as in Example 1. The results are shown in Table 6 below.

[0091] 2. Preparation of cement-based pavement materials

[0092] (S1) Preparation of a hydrogel initiating solution: 5 parts by weight of poly (N-isopropylacrylamide) (NIPAm), 1.5 parts by weight of sodium acrylate (SA), 0.12 parts by weight of N,N'-methylenebisacrylamide, 0.12 parts by weight of ammonium persulfate, and 60 parts by weight of water. Mix these components and stir until uniformly distributed to obtain a hydrogel initiating solution, which is then set aside.

[0093] (S2) Take the following raw materials in the following proportions: 60 parts by weight of 42.5 ordinary Portland cement, 0.5 parts by weight of the hydrogel accelerator prepared in step 1 of this embodiment, and 60 parts by weight of the hydrogel initiating solution prepared in step (S1).

[0094] (S3) The 42.5% ordinary Portland cement and the hydrogel initiating solution from step (S2) were added to the hydrogel accelerator, followed by continuous stirring at 1200 rpm for 3 minutes to obtain a cement-based pavement material. The material was then allowed to stand for 10 minutes, and after solidification and hardening, its various properties were tested using the same testing methods as in Example 1. The results are shown in Table 6 below.

[0095] Table 6 Comparative Example 3 pavement material performance results

[0096]

[0097] Comparative Example 4

[0098] The preparation of cement-based pavement material is the same as that in Example 2, except that no hydrogel accelerator is prepared. Instead, lithium aluminosilicate is directly used to prepare the cement-based pavement material, as follows:

[0099] (S1) Preparation of a hydrogel initiating solution: 1 part by weight of poly (N-isopropylacrylamide) (NIPAm), 0.3 parts by weight of sodium acrylate (SA), 0.03 parts by weight of N,N-methylenebisacrylamide, 0.03 parts by weight of sodium persulfate, and 20 parts by weight of water. Mix these components and stir until uniformly distributed to obtain a hydrogel initiating solution, which is then set aside.

[0100] (S2) Take the following raw materials in the following proportions: 20 parts by weight of 42.5 ordinary Portland cement, 0.2 parts by weight of lithium aluminosilicate (LiAlSiO4), and 20 parts by weight of the hydrogel initiating solution prepared in this example.

[0101] (S3) The 42.5% ordinary Portland cement and hydrogel initiating solution from step (S2) were mixed with lithium aluminosilicate, and then stirred continuously at 1200 rpm for 3 minutes to obtain a cement-based pavement material. The material was then allowed to stand for 10 minutes, and after solidification and hardening, its various properties were tested using the same testing methods as in Example 1. The results are shown in Table 7 below.

[0102] Table 7 Comparative Example 4 Road Surface Material Performance Results

[0103]

[0104] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art will be able to modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein with equivalents. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A high-interfacial-activity in-situ self-assembled tough cement-based pavement material, characterized in that: The pavement material comprises the following raw materials in parts by weight: 20-60 parts of a cementitious material containing silicate cement, 0.2-0.5 parts of a hydrogel accelerator, and 1-7 parts of a hydrogel initiating solution, wherein the hydrogel initiating solution comprises 1-5 parts of poly (N-isopropylacrylamide), 0.3-1.5 parts of sodium acrylate, 0.03-0.12 parts of a cross-linking agent, 0.03-0.12 parts of an initiator, and 20-60 parts of water; the chemical structure of the hydrogel accelerator is shown in formula (1): Formula (1); The preparation method of the hydrogel accelerator comprises the following steps: (1) placing tetramethylenediamine in an alkaline solution for surface treatment, adjusting to neutrality, adding a silane coupling agent, and heating for reaction to obtain a system containing an intermediate; the silane coupling agent includes γ-methacryloxypropyltrimethoxysilane, the mass ratio of tetramethylenediamine to the silane coupling agent is 0.1-0.3:0.03-0.08, the heating reaction temperature is 40-80°C, and the heating reaction time is 0.5-3.5h; (2) Adding lithium aluminosilicate to the system containing the intermediate obtained in step (1) and heating the system to react, thereby obtaining a hydrogel accelerator; the mass ratio of tetramethylenediamine to lithium aluminosilicate is 0.1-0.3:0.08-0.2, the heating reaction temperature is 50-95°C, and the heating reaction time is 1.5-5.5h.

2. The high interfacial activity in-situ self-assembled tough cement-based pavement material according to claim 1, characterized in that: In step (1), the alkali solution includes at least one of a sodium hydroxide solution and a potassium hydroxide solution, and the concentration of the alkali solution is 0.03-0.25 mol / L.

3. The high interfacial activity in-situ self-assembled tough cement-based pavement material according to claim 1, characterized in that: In step (1), an acidic substance is used to adjust the solution to neutrality, and the acidic substance includes at least one of nitric acid and sulfuric acid.

4. The high interfacial activity in-situ self-assembly tough cement-based pavement material according to claim 1, characterized in that: In step (1), continuous stirring is performed during the reaction.

5. The high interfacial activity in-situ self-assembly tough cement-based pavement material according to claim 1, characterized in that: In step (2), continuous stirring is performed during the reaction.

6. The high interfacial activity in-situ self-assembly tough cement-based pavement material according to claim 1, characterized in that: The initiator includes at least one of potassium persulfate, ammonium persulfate, and sodium persulfate, and the cross-linking agent includes at least one of N,N-methylenebisacrylamide and N,N'-methylenebisacrylamide.

7. The method for preparing the in-situ self-assembled tough cement-based pavement material with high interfacial activity according to any one of claims 1 to 6, characterized in that: The following steps are involved: The gelling material containing silicate cement and the hydrogel initiating solution are added to the hydrogel accelerator and mixed evenly to obtain the product.

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