A trenchless rapid asphalt repair material and its preparation method and application

Abstract

The present invention relates to the technical field of road repair materials, specifically disclosing a trenchless rapid asphalt repair material, its preparation method, and its application. The material comprises a binder and aggregate. The binder comprises 80-100 parts of SBS-modified emulsified asphalt, 10-15 parts of an anti-cracking modifier, 0.8-1 part of a dispersant, and 8-10 parts of a reinforcing agent. The anti-cracking modifier is a modified rubber powder blend obtained by sequentially modifying rubber powder with a silane coupling agent and petroleum ether. The aggregate comprises 0.3-1 part of basalt fiber, 4.5-9 parts of powder, 75-90 parts of crushed stone, and 5.2-15 parts of lignin-based boric acid-functionalized carbon nanotubes. The lignin-based boric acid-functionalized carbon nanotubes are obtained by modifying lignin with boric acid-functionalized carbon nanotubes. The trenchless rapid asphalt repair material of the present invention combines fluidity and strength, enabling trenchless repair of shallow or thin potholes on roads.

Description

Technical Field

[0001] The present invention relates to the technical field of road repair materials, and in particular to a trenchless rapid asphalt repair material and a preparation method and application thereof. Background Art

[0002] Asphalt pavement is the preferred premium paving material in road construction due to its exceptional performance. By mixing asphalt with mineral materials, this material creates a highly durable paving material that can withstand frequent heavy-duty vehicle use and extreme weather conditions. The resulting pavement is smooth, waterproof, and has a long service life.

[0003] Although asphalt pavements are favored for their ease of maintenance and durability, with the increase in traffic volume and vehicle weight, cracks and potholes are inevitable. Cracks are usually repaired with caulking glue, while potholes are usually repaired by excavation and filling. Among them, the excavation and filling method is to deep-cut and excavate the diseased area where the pothole is formed, fill it with hot-mix or cold-patch asphalt, and then compact it with a plate ram or roller to repair it. Due to the poor fluidity of hot-mix asphalt and cold-patch asphalt, shallow or thin-layered potholes can only be expanded by excavation to fill the pothole with asphalt mixture. This repair method is inefficient and wastes a lot of resources, which greatly increases the cost of pavement disease treatment and maintenance.

[0004] Emulsified asphalt mixtures have excellent fluidity. Theoretically, using them to repair potholes in asphalt pavements eliminates the need for excavation and expansion of the affected area. Instead, the emulsified asphalt can be directly filled into the pothole to complete the repair. However, using emulsified asphalt directly to repair potholes prevents rapid formation and results in low initial strength. This results in poor durability, compressive strength, and crack resistance in the repaired area, ultimately leading to cracking in the repaired area. Summary of the Invention

[0005] The purpose of the present invention is to provide a trenchless rapid asphalt repair material, which has both fluidity and strength and can repair shallow or thin potholes on the road surface in a trenchless manner.

[0006] In addition, the present invention also provides a preparation method and application of the above-mentioned trenchless rapid asphalt repair material.

[0007] The present invention is achieved through the following technical solutions:

[0008] A trenchless rapid asphalt repair material comprises a binder and aggregate; the binder comprises, by weight, 80-100 parts of SBS modified emulsified asphalt, 10-15 parts of an anti-cracking modifier, 0.8-1 part of a dispersant, and 8-10 parts of a reinforcing agent; the anti-cracking modifier is a modified rubber powder blend obtained by sequentially modifying rubber powder with a silane coupling agent and petroleum ether;

[0009] The aggregate includes: 0.3 to 1 parts of basalt fiber, 4.5 to 9 parts of powder, 75 to 90 parts of crushed stone, and 5.2 to 15 parts of lignin-based boric acid functionalized carbon nanotubes; the lignin-based boric acid functionalized carbon nanotubes are obtained by modifying lignin with boric acid functionalized carbon nanotubes, and the boric acid functionalized carbon nanotubes are obtained by reacting oxidized carbon nanotubes with 3-aminophenylboronic acid monohydrate.

[0010] Emulsified asphalt is a road construction material with very low viscosity and good fluidity. It can be used at room temperature and can also be used with cold, wet stones. Although emulsified asphalt can meet the fluidity requirements for trenchless repair of roadbed potholes, the strength after repair is low, making the repaired roadbed poorly resistant to cracking and resulting in a short service life of the repaired roadbed.

[0011] The SBS-modified emulsified asphalt used in this invention not only has the advantages of good fluidity compared to conventional emulsified asphalt, but also has high-temperature resistance, durability, and crack resistance. Using SBS-modified emulsified asphalt as a carrier material for a binder can improve the crack resistance of asphalt repair materials to a certain extent. However, using SBS-modified emulsified asphalt directly also fails to meet the required compressive strength of the roadbed. Therefore, when using BS-modified emulsified asphalt to repair shallow or thin potholes in a road surface, it is necessary to further improve the bonding strength of the repair material.

[0012] The present invention can improve the impact strength of SBS modified emulsified asphalt and further improve its crack resistance by adding an anti-cracking modifier, a dispersant and a reinforcing agent into the binder and cooperating with the SBS modified emulsified asphalt. Among them, the anti-cracking modifier plays a major role in enhancing the impact strength and tensile strength, the dispersant can improve the dispersion effect of the anti-cracking modifier and the reinforcing agent in the SBS modified emulsified asphalt, and the reinforcing agent can improve the bonding effect between the binder and the aggregate, so as to ultimately improve the strength after repair.

[0013] Rubber powder has strong toughness. Adding it to SBS modified emulsified asphalt can improve its impact toughness. However, the compatibility of rubber powder with SBS modified emulsified asphalt after swelling is poor, and the dispersibility of rubber powder in SBS modified emulsified asphalt is poor. If rubber powder is directly added to SBS modified emulsified asphalt, the toughening effect can be effective, and it may even lead to the opposite effect due to agglomeration. Therefore, the application of rubber powder in SBS modified emulsified asphalt is limited.

[0014] The present invention uses a silane coupling agent to modify rubber powder, which can improve the dispersibility of the rubber powder in SBS modified emulsified asphalt. By blending the modified rubber powder with petroleum ether, the compatibility of the modified rubber powder and the SBS modified emulsified asphalt can be improved. That is, the rubber powder of the present invention is added to the SBS modified emulsified asphalt in the form of a modified rubber powder blending liquid, and has good compatibility and dispersibility with the SBS modified emulsified asphalt, achieving the toughening effect of the rubber powder on the SBS modified emulsified asphalt, thereby improving the impact strength and tensile strength of the SBS modified emulsified asphalt.

[0015] In order to improve the tensile strength of the repair material, fibers are usually added to the aggregate. However, adding fibers alone will only increase the tensile strength to a limited extent. The present invention adds lignin-based boric acid functionalized carbon nanotubes to the aggregate, which work together with basalt fibers to significantly improve the tensile strength of the repair material, so that the repaired roadbed has higher tensile strength.

[0016] Lignin has the advantage of hardness. Adding lignin to aggregate can improve the tensile strength of the repair material to a certain extent, but the increase is limited. Lignin modified with carbon nanotubes can further improve the tensile strength of lignin and help improve impact strength, but the dispersibility is poor. Compared with the lignin modified with carbon nanotubes, the lignin-based boric acid functionalized carbon nanotubes of the present invention not only retain the tensile strength, but also have higher dispersibility, so as to achieve the enhancement effect on the repair material.

[0017] In summary, the repair material of the present invention has both fluidity and strength, and can repair shallow or thin potholes on the road surface in a trenchless manner.

[0018] In addition, the repair material of the present invention uses a non-excavation method to repair shallow or thin potholes on the road surface, without the need to excavate to expand the diseased area. The repair material can be directly filled into the pothole to achieve repair by utilizing its good fluidity, which can achieve rapid repair.

[0019] In a preferred embodiment, the preparation process of the modified rubber powder blend is as follows:

[0020] The rubber powder is pretreated so that its surface contains active groups that can react with a silane coupling agent; the pretreated rubber powder is blended with the silane coupling agent for modification and then dried to obtain modified rubber powder; the modified rubber powder is blended with petroleum ether to obtain a modified rubber powder blending liquid.

[0021] The modified rubber powder was mixed with petroleum ether to obtain a modified rubber powder blending liquid which has good compatibility with SBS modified emulsified asphalt. The reason is that both have carbon chain structures.

[0022] In a preferred embodiment, the pretreatment process of the rubber powder includes soaking, grinding and drying with a sodium hypochlorite solution.

[0023] In a preferred embodiment, the mass percentage of petroleum ether to modified rubber powder is 1:(3-10).

[0024] In a preferred embodiment, the mass percentage of petroleum ether to modified rubber powder is 1:(5-6).

[0025] If the amount of petroleum ether is too small, the compatibility between the modified rubber powder blend and SBS modified emulsified asphalt will be poor. If the amount of petroleum ether is too large, the compatibility will not be significantly increased.

[0026] In a preferred embodiment, nano-silicon dioxide is added during the blending of the modified rubber powder and petroleum ether, and the nano-silicon dioxide accounts for 5 to 8% of the modified rubber powder by mass.

[0027] The addition of nano-silica can further improve the compatibility of rubber powder and SBS modified emulsified asphalt.

[0028] In a preferred embodiment, the preparation process of lignin-based boric acid functionalized carbon nanotubes is as follows:

[0029] The carbon nanotubes are subjected to oxidation purification treatment, and then the oxidized and purified carbon nanotubes are dispersed in water to form an aqueous solution; a protective agent and a cross-linking agent are then added in sequence and stirred, and 3-aminophenylboronic acid monohydrate is then added and stirred to react to obtain boric acid functionalized carbon nanotubes;

[0030] The boric acid functionalized carbon nanotubes are dispersed in an organic solvent, diphenylmethane-4,4'-diisocyanate is added, and the mixture is stirred under a nitrogen atmosphere. Then, lignin and a catalyst are added and stirred for reaction to obtain lignin-based boric acid functionalized carbon nanotubes.

[0031] Oxidation purification of carbon nanotubes can not only remove impurities in carbon nanotubes and increase the purity of carbon nanotubes, but also change the physical and chemical properties of carbon nanotubes and enhance their dispersibility and solubility.

[0032] In a preferred embodiment, the oxidizing agent used in the oxidation purification treatment includes nitric acid; the protecting agent includes N-hydroxysuccinimide; the cross-linking agent includes 1-ethyl-(3-dimethylaminopropyl)carbodiimide; and the catalyst includes dibutyltin dilaurate.

[0033] In a preferred embodiment, the process of oxidation purification is as follows:

[0034] The carbon nanotubes are dispersed in an oxidant, and then reflux-heated at 140-150° C. After the reflux-heating is completed, the mixture is cooled and centrifuged to obtain a precipitate.

[0035] In a preferred embodiment, the process of dispersing the boric acid-functionalized carbon nanotubes in an organic solvent is as follows:

[0036] Ultrasonicate at 450-500°C for 40-60 minutes.

[0037] In a preferred embodiment, the dispersant includes at least one of polyvinyl alcohol and polyacrylic acid.

[0038] In a preferred embodiment, the reinforcing agent comprises a waterborne epoxy resin.

[0039] In a preferred embodiment, the crushed stone includes hard crushed stone made of basalt, limestone, granite and other materials; the powder includes at least one of mineral powder, talcum powder and calcium bicarbonate powder.

[0040] In a preferred embodiment, the maximum nominal particle size of the crushed stone is determined based on the repair thickness, and the maximum nominal particle size is 1 / 3-1 of the repair thickness.

[0041] A method for preparing a trenchless rapid asphalt repair material, comprising preparing a binder and an aggregate separately;

[0042] The preparation process of the binder is as follows:

[0043] Add the anti-cracking modifier to the SBS modified emulsified asphalt at 30-60°C and stir at 400-800 rpm for 30-40 minutes; then add the dispersant and reinforcing agent and stir at 300-600 rpm for 10-15 minutes;

[0044] The preparation process of aggregate is as follows:

[0045] The basalt fibers, powder, crushed stone and lignin-based boric acid functionalized carbon nanotubes are mixed uniformly.

[0046] A trenchless rapid asphalt patching material is used to repair potholes in roadbeds. Water is added to the aggregate to wet it, and then a binder is added. After stirring for 2 to 3 minutes, the mixed trenchless rapid asphalt patching material is directly poured into the pothole and smoothed.

[0047] In a preferred embodiment, the mass ratio of binder to aggregate is (10-20): (80-90); in terms of mass percentage, water accounts for 3-5% of the aggregate.

[0048] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0049] The present invention significantly improves the impact strength and tensile strength of the repair material by adding an anti-cracking modifier, a dispersant and a reinforcing agent to the binder and cooperating with SBS modified emulsified asphalt; and significantly improves the strength of the repair material by adding lignin-based boric acid functionalized carbon nanotubes to the aggregate and cooperating with basalt fibers, ultimately making the repair material both fluid and high-strength, enabling trenchless repair of shallow or thin potholes on the road surface, and the high strength of the repaired road surface gives it the advantage of a long service life. DETAILED DESCRIPTION

[0050] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is further described in detail below in conjunction with the examples. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention. The embodiments described below are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0051] In the following description, numerous specific details are set forth to provide a thorough understanding of the present invention. However, it will be apparent to one of ordinary skill in the art that these specific details are not necessarily required to practice the present invention. In other examples, well-known structures, materials, or methods are not specifically described to avoid obscuring the present invention. The materials, instruments, and reagents used in the following examples, unless otherwise specified, are commercially available. The techniques used in the examples, unless otherwise specified, are conventional techniques well known to those skilled in the art.

[0052] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. Throughout the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0053] Example:

[0054] In order to achieve trenchless repair of shallow or thin pothole damage areas on the road surface, it is necessary to prepare a repair material that has both fluidity and strength, a trenchless rapid asphalt repair material, including a binder and aggregate; the binder and aggregate are prepared separately and packaged independently, and then mixed according to proportion when used.

[0055] Calculated by weight, the binder includes: 80 to 100 parts of SBS modified emulsified asphalt, 10 to 15 parts of anti-cracking modifier, 0.8 to 1 part of dispersant, and 8 to 10 parts of reinforcing agent.

[0056] Among them, SBS modified emulsified asphalt is an existing product purchased from Daozhijian (Shanghai) New Materials Co., Ltd.

[0057] The anti-cracking modifier is a modified rubber powder blend obtained by sequentially modifying rubber powder with a silane coupling agent and petroleum ether. Specifically, the preparation process of the modified rubber powder blend is as follows:

[0058] The rubber powder is pretreated so that its surface contains active groups that can react with a silane coupling agent; the pretreated rubber powder is blended with the silane coupling agent for modification and then dried to obtain modified rubber powder; the modified rubber powder is blended with petroleum ether to obtain a modified rubber powder blending liquid.

[0059] In a specific case, the preparation process of the modified rubber powder blend is as follows:

[0060] Rubber powder (styrene-butadiene rubber powder) was mixed with a sodium hypochlorite solution at a mass ratio of 1:1 and then wet-ball milled and dried to impart reactive groups, such as hydroxyl groups, to the rubber powder's surface. A 0.5% KH550 solution was prepared using water as the solvent. The pretreated rubber powder was then added to the silane coupling agent solution and stirred evenly. The solid-liquid ratio for the coupling agent modification was 200g of rubber powder per 2L of silane coupling agent solution. The rubber powder was then allowed to react in a dry environment until the surface of the rubber powder particles was completely dry, yielding the modified rubber powder. The silane coupling agent KH550 hydrolyzed in water to produce silanol groups, which reacted with the -OH groups in the rubber powder, achieving silane coupling agent modification and improving its dispersibility in SBS-modified emulsified asphalt. The modified rubber powder was then blended with petroleum ether for 30 minutes to obtain a modified rubber powder blend solution, which improved its compatibility with the SBS-modified emulsified asphalt. The mass percentage of petroleum ether to modified rubber powder is 1:(3-10); preferably, the mass percentage of petroleum ether to modified rubber powder is 1:(5-6).

[0061] In a preferred embodiment, nano-silicon dioxide is added during the blending of the modified rubber powder and petroleum ether, and the nano-silicon dioxide accounts for 5-8% of the modified rubber powder by mass.

[0062] The dispersant includes at least one of polyvinyl alcohol (CAS#: 9002-89-5) and polyacrylic acid (CAS#: 9003-01-4). The dispersant is added to improve the uniformity of the anti-cracking modifier and reinforcing agent in the SBS-modified emulsified asphalt. Polyvinyl alcohol was purchased from SIGMA-ALDRICH; polyacrylic acid was purchased from Jiyu Juji New Materials Co., Ltd.

[0063] The reinforcing agent includes water-based epoxy resin or water-based polyurethane, which is used to improve the bonding between the binder and the aggregate. Specifically, water-based epoxy resin EP137, water-based polyurethane PU104, etc. can be used.

[0064] Calculated by weight, the aggregate includes: 0.3 to 1 parts of basalt fiber, 4.5 to 9 parts of powder, 75 to 90 parts of crushed stone, and 5.2 to 15 parts of lignin-based boric acid functionalized carbon nanotubes.

[0065] The length of basalt fiber is 3-6 mm, the thickness is 0.18 mm, and the surface density is 200±20 g / m 2 .

[0066] The crushed stone includes hard crushed stone made of basalt, limestone, granite and other materials; the powder includes at least one of mineral powder, talcum powder and bicarbonate powder; and the particle size is 200 to 400 meshes.

[0067] Among them, the particle size of the gravel is determined based on the size of the pit depth. In actual use, the corresponding gravel can be configured based on the pit depth. The pit depth is 1 to 3 times the maximum nominal particle size of the gravel. For example, when the pit depth is 1 cm, the particle size of the gravel is 3 to 5 mm.

[0068] The lignin-based boric acid functionalized carbon nanotubes are obtained by modifying lignin with boric acid functionalized carbon nanotubes, and the boric acid functionalized carbon nanotubes are obtained by reacting oxidized carbon nanotubes with 3-aminophenylboronic acid monohydrate. Specifically, the preparation process of the lignin-based boric acid functionalized carbon nanotubes is as follows:

[0069] The carbon nanotubes are subjected to an oxidation purification treatment, specifically, the carbon nanotubes are dispersed in an oxidant, and then reflux-heated at 140-150° C. After the reflux heating is completed, the carbon nanotubes are cooled and centrifuged to obtain a precipitate; the oxidatively purified carbon nanotubes are then dispersed in water to form an aqueous solution; a protective agent and a cross-linking agent are then added in sequence with stirring, and 3-aminophenylboronic acid monohydrate is then added and reacted with stirring to obtain boric acid-functionalized carbon nanotubes;

[0070] The boric acid functionalized carbon nanotubes are dispersed in an organic solvent, chloroform. The process of dispersing the boric acid functionalized carbon nanotubes in the organic solvent is as follows: ultrasonication at 450-500° C. for 40-60 minutes; diphenylmethane-4,4'-diisocyanate is added after dispersion, stirring under a nitrogen atmosphere, and then lignin and a catalyst are added, stirring and reacting to obtain lignin-based boric acid functionalized carbon nanotubes.

[0071] In a specific case, the oxidizing agent used in the oxidation purification treatment is nitric acid; the protective agent is N-hydroxysuccinimide; the cross-linking agent is 1-ethyl-(3-dimethylaminopropyl)carbodiimide; and the catalyst is dibutyltin dilaurate.

[0072] In a specific case, the preparation process of lignin-based boric acid functionalized carbon nanotubes is as follows:

[0073] The carbon nanotubes were dispersed in 30% HNO3 and then refluxed at 140°C for 24 hours. After the mixed solution was naturally cooled, it was centrifuged to obtain a precipitate, which was washed with deionized water until the pH of the washing solution was 7. The precipitate was dried in an oven for 12 hours. The dried precipitate was taken and dispersed in deionized water to obtain a mixed solution with a concentration of 1 mg / mL. 0.017 g of N-hydroxysuccinimide (CAS: 6066-82-6) was added to 50 mL of the mixed solution and stirred vigorously. Then, 0.03 g of 1-ethyl-(3-dimethylaminopropyl)carbodiimide was added. The mixed solution was continued to be stirred at room temperature for 1 hour, 0.025 g of 3-aminophenylboronic acid monohydrate was added, and then the reaction was stirred at 30°C for 24 hours. The precipitate was then washed with deionized water several times to obtain boric acid-functionalized carbon nanotubes.

[0074] 5 g of boric acid-functionalized carbon nanotubes were dispersed in 500 mL of chloroform and ultrasonicated at 500 ° C for 40 min. 2 mL of diphenylmethane-4,4'-diisocyanate was added and stirred for 1 h under a nitrogen atmosphere. 3 g of lignin and 2 drops of dibutyltin dilaurate (CAS#: 77-58-7) were then added and stirred for 3 h. The mixed solution was then filtered to obtain a precipitate, which was washed three times with chloroform and then dried in vacuo at 70 ° C to obtain lignin-based boric acid-functionalized carbon nanotubes.

[0075] 1-Ethyl-(3-dimethylaminopropyl)carbodiimide (EDC, CAS: 25952-53-8), 3-aminophenylboronic acid monohydrate (APBA, CAS: 206658-89-1), diphenylmethane-4,4′-diisocyanate (MDI, CAS: 101-68-8), and carbon nanotubes (CAS: 308068-56-6, product number 698849) were purchased from SIGMA-ALDRICH;

[0076] The method for preparing the above-mentioned trenchless rapid asphalt repair material comprises preparing the binder and the aggregate separately;

[0077] The preparation process of the binder is as follows:

[0078] Add anti-cracking modifier to SBS modified emulsified asphalt at 30-60°C and shear at 400-800 rpm for 30-40 minutes; then add dispersant and reinforcing agent and stir at 300-600 rpm for 10-15 minutes.

[0079] In a specific case, the SBS modified emulsified asphalt was heated to 60°C, the anti-cracking modifier was added, and the mixture was stirred at 600 rpm for 30 minutes. After cooling to 40°C, the dispersant and reinforcing agent were added, and the mixture was stirred at 400 rpm for 10 minutes.

[0080] The preparation process of aggregate is as follows:

[0081] The basalt fibers, powder, crushed stone and lignin-based boric acid functionalized carbon nanotubes are mixed in proportion and stirred evenly.

[0082] The trenchless rapid asphalt repair material of the present invention can significantly improve the impact strength and tensile strength of the repair material by adding an anti-cracking modifier, a dispersant and a reinforcing agent to the binder and cooperating with SBS modified emulsified asphalt; by adding lignin-based boric acid functionalized carbon nanotubes to the aggregate and acting together with basalt fiber, the strength of the repair material can be greatly improved, and ultimately the repair material has both fluidity and high strength, which can realize the trenchless repair of roadbed potholes, and the repaired roadbed has the advantage of a long service life due to its high strength.

[0083] When trenchless rapid asphalt repair materials are used to repair roadbed potholes, add water to the aggregate and stir to moisten it, then add the binder and stir for 2 to 3 minutes. Then pour the mixed trenchless rapid asphalt repair material directly into the pothole and smooth it out.

[0084] Specifically, the mass ratio of binder to aggregate is (10-20): (80-90); in terms of mass percentage, water accounts for 3-5% of the aggregate.

[0085] In order to better illustrate the effect of this embodiment, the following specific cases are used for illustration.

[0086] Example 1:

[0087] A trenchless rapid asphalt repair material comprises a binder and an aggregate; the binder and the aggregate are prepared separately and packaged independently, and then mixed in proportion when used.

[0088] The binder comprises, by weight, 100 parts of SBS modified emulsified asphalt, 15 parts of an anti-cracking modifier, 1 part of a dispersant, and 10 parts of a reinforcing agent; the anti-cracking modifier is a modified rubber powder blend obtained by sequentially modifying rubber powder with a silane coupling agent and petroleum ether. The preparation process of the modified rubber powder blend is similar to that of the above embodiment.

[0089] In parts by weight, the aggregate includes: 0.5 parts of basalt fiber, 8 parts of powder, 83.5 parts of crushed stone, and 8 parts of lignin-based boric acid-functionalized carbon nanotubes; the lignin-based boric acid-functionalized carbon nanotubes are obtained by modifying lignin with boric acid-functionalized carbon nanotubes, and the boric acid-functionalized carbon nanotubes are obtained by reacting oxidized carbon nanotubes with 3-aminophenylboronic acid monohydrate; the specific modification process refers to the above embodiment.

[0090] Example 2:

[0091] This embodiment is based on Example 1, and differs from Example 1 in that the amounts of the components are different, specifically:

[0092] A trenchless rapid asphalt repair material comprising a binder and aggregate;

[0093] By weight, the binder includes: 80 parts of SBS modified emulsified asphalt, 10 parts of anti-cracking modifier, 0.8 parts of dispersant, and 8 parts of reinforcing agent;

[0094] In parts by weight, the aggregate includes: 1 part of basalt fiber, 5 parts of powder, 89 parts of crushed stone, and 5.2 parts of lignin-based boric acid functionalized carbon nanotubes.

[0095] Example 3:

[0096] This embodiment is based on Example 1, and differs from Example 1 in that the amount of the anti-cracking modifier is reduced, specifically:

[0097] A trenchless rapid asphalt repair material comprising a binder and aggregate;

[0098] By weight, the binder includes: 100 parts of SBS modified emulsified asphalt, 10 parts of anti-cracking modifier, 1 part of dispersant, and 10 parts of reinforcing agent;

[0099] In parts by weight, the aggregate includes: 0.5 parts of basalt fiber, 8 parts of powder, 83.5 parts of crushed stone, and 8 parts of lignin-based boric acid functionalized carbon nanotubes.

[0100] Example 4:

[0101] This embodiment is based on Example 1, and differs from Example 1 in that the amount of lignin-based boric acid functionalized carbon nanotubes is reduced. Specifically:

[0102] A trenchless rapid asphalt repair material comprising a binder and aggregate;

[0103] By weight, the binder includes: 100 parts of SBS modified emulsified asphalt, 15 parts of anti-cracking modifier, 1 part of dispersant, and 10 parts of reinforcing agent;

[0104] In parts by weight, the aggregate includes: 0.5 parts of basalt fiber, 8 parts of powder, 83.5 parts of crushed stone, and 5 parts of lignin-based boric acid functionalized carbon nanotubes.

[0105] Example 5:

[0106] This embodiment is based on Example 1, and differs from Example 1 in that the amount of lignin-based boric acid functionalized carbon nanotubes is increased. Specifically:

[0107] A trenchless rapid asphalt repair material comprising a binder and aggregate;

[0108] By weight, the binder includes: 100 parts of SBS modified emulsified asphalt, 15 parts of anti-cracking modifier, 1 part of dispersant, and 10 parts of reinforcing agent;

[0109] In parts by weight, the aggregate includes: 0.5 parts of basalt fiber, 8 parts of powder, 83.5 parts of crushed stone, and 10 parts of lignin-based boric acid functionalized carbon nanotubes.

[0110] Example 6:

[0111] This embodiment is based on Example 1, and differs from Example 1 in that the amount of lignin-based boric acid functionalized carbon nanotubes is increased. Specifically:

[0112] A trenchless rapid asphalt repair material comprising a binder and aggregate;

[0113] By weight, the binder includes: 100 parts of SBS modified emulsified asphalt, 15 parts of anti-cracking modifier, 1 part of dispersant, and 10 parts of reinforcing agent;

[0114] In parts by weight, the aggregate includes: 0.5 parts of basalt fiber, 8 parts of powder, 83.5 parts of crushed stone, and 13 parts of lignin-based boric acid functionalized carbon nanotubes.

[0115] Example 7:

[0116] This embodiment is based on Example 1, and differs from Example 1 in that the amount of lignin-based boric acid functionalized carbon nanotubes is increased. Specifically:

[0117] A trenchless rapid asphalt repair material comprising a binder and aggregate;

[0118] By weight, the binder includes: 100 parts of SBS modified emulsified asphalt, 15 parts of anti-cracking modifier, 1 part of dispersant, and 10 parts of reinforcing agent;

[0119] In parts by weight, the aggregate includes: 0.5 parts of basalt fiber, 8 parts of powder, 83.5 parts of crushed stone, and 15 parts of lignin-based boric acid functionalized carbon nanotubes.

[0120] Example 8:

[0121] This embodiment is based on embodiment 1, and differs from embodiment 1 in that:

[0122] In the process of preparing the modified rubber powder blending liquid, nano silicon dioxide is added during the blending of the modified rubber powder and petroleum ether, and the nano silicon dioxide accounts for 8% of the modified rubber powder in terms of mass percentage.

[0123] Comparative Example 1:

[0124] This comparative example is based on Example 1, and differs from Example 1 in that the binder does not contain an anti-cracking modifier.

[0125] A trenchless rapid asphalt repair material comprising a binder and aggregate;

[0126] By weight, the binder includes: 100 parts of SBS modified emulsified asphalt, 1 part of dispersant, and 10 parts of reinforcing agent;

[0127] In parts by weight, the aggregate includes: 0.5 parts of basalt fiber, 8 parts of powder, 83.5 parts of crushed stone, and 8 parts of lignin-based boric acid functionalized carbon nanotubes.

[0128] Comparative Example 2:

[0129] This comparative example is based on Example 1, and differs from Example 1 in that an equal amount of rubber powder is used in the binder to replace the anti-cracking modifier.

[0130] Comparative Example 3:

[0131] This comparative example is based on Example 1, and differs from Example 1 in that an equal amount of modified rubber powder is used in the binder to replace the anti-cracking modifier.

[0132] Comparative Example 4:

[0133] This comparative example is based on Example 1, and differs from Example 1 in that an equal amount of lignin is used in the aggregate to replace the lignin-based boric acid functionalized carbon nanotubes.

[0134] A trenchless rapid asphalt repair material comprising a binder and aggregate;

[0135] By weight, the binder includes: 100 parts of SBS modified emulsified asphalt, 15 parts of anti-cracking modifier, 1 part of dispersant, and 10 parts of reinforcing agent;

[0136] In parts by weight, the aggregate includes: 0.5 parts of basalt fiber, 8 parts of powder, 83.5 parts of crushed stone, and 8 parts of lignin.

[0137] Comparative Example 5:

[0138] This comparative example is based on Example 1, and differs from Example 1 in that an equal amount of carbon nanotube-modified lignin is used in the aggregate to replace the lignin-based boric acid functionalized carbon nanotubes.

[0139] The preparation process of nanotube-modified lignin is as follows:

[0140] Take 5g of carbon nanotubes and disperse them in 500mL of chloroform. Ultrasonicate at 500℃ for 40min; add 2mL of diphenylmethane-4,4'-diisocyanate and stir for 1h under nitrogen atmosphere; then add 3g of lignin and 2 drops of dibutyltin dilaurate and continue stirring for 3h; then filter the mixed solution to obtain a precipitate, wash the precipitate with chloroform 3 times, and then vacuum dry at 70℃ to obtain carbon nanotube-modified lignin.

[0141] Comparative Example 6:

[0142] This comparative example is based on comparative example 4, and differs from comparative example 4 in that 2 parts of sodium tetraborate are added, specifically:

[0143] A trenchless rapid asphalt repair material comprising a binder and aggregate;

[0144] In parts by weight, the binder includes: 100 parts of SBS modified emulsified asphalt, 15 parts of anti-cracking modifier, 1 part of dispersant, 10 parts of reinforcing agent, and 2 parts of sodium tetraborate;

[0145] In parts by weight, the aggregate includes: 0.5 parts of basalt fiber, 8 parts of powder, 83.5 parts of crushed stone, and 8 parts of lignin.

[0146] The repair materials of Examples 1-8 and Comparative Examples 1-6 were prepared into test specimens using the following method. The tensile strength and impact strength of each specimen were tested. Tensile strength was measured in accordance with GB / T 1040.3-2006, "Plastics - Determination of Tensile Properties," at a tensile speed of 2 mm / min. Three specimens were taken from each group, and the results were averaged. Impact strength was measured in accordance with GB / T 1843-2008, "Plastics - Determination of Izod Impact Strength." Three specimens were taken from each group, and the results were averaged. The results are shown in Table 1.

[0147] The preparation process of the specimen is as follows: add water to the aggregate and stir to moisten it, with water accounting for 3% of the aggregate by mass; then add the binder and stir for 2 minutes, then directly pour the mixed trenchless rapid asphalt repair material into a pit with a designed width of 1 cm, a depth of 5 cm, and a length of 20 cm, smooth it, and take out the specimen after the repair material solidifies; the mass ratio of binder to aggregate is 20:80.

[0148] Table 1

[0149]

[0150] From the data in Table 1, we can see that:

[0151] 1) The impact strength of the repair materials prepared in each embodiment of the present invention is 14.0KJ / m 2 The above shows that the crack-resistant modifier obtained by modifying rubber powder in the present invention utilizes the elasticity of rubber powder to achieve toughening effect on the repair material, thereby improving its crack resistance and being able to withstand stronger impact force.

[0152] 2) The anti-cracking modifier has a greater impact on the impact strength of the repair material and a smaller impact on the tensile strength of the repair material. That is, the anti-cracking modifier can improve the toughness of the repair material and thus improve its impact strength. Although rubber powder can improve the toughness of asphalt, whether it is modified and the modification method will affect its effect in improving the impact strength of the material. This is due to the compatibility and dispersibility between rubber powder and emulsified asphalt.

[0153] 3) Lignin-based boric acid functionalized carbon nanotubes have a greater impact on the tensile strength of the repair material and a smaller impact on the impact strength of the repair material. The present invention can significantly improve the tensile strength of the repair material by adding lignin-based boric acid functionalized carbon nanotubes to the aggregate. Compared with lignin-based boric acid functionalized carbon nanotubes, the tensile strength of the repair material is reduced by adding lignin and carbon nanotube-modified lignin.

[0154] 4) The present invention can improve the tensile strength and impact strength of the repair material by adding an anti-cracking modifier to the binder and lignin-based boric acid functionalized carbon nanotubes to the aggregate. In addition, SBS-modified emulsified asphalt has the advantage of good fluidity, so the repair material prepared by the present invention can be used for repairing roadbed potholes by non-excavation methods.

[0155] Furthermore, the trenchless asphalt patch materials prepared in Examples 1 to 8 were tested at 25°C in accordance with JTG E20-211, "Test Procedures for Highway Asphalt and Asphalt Mixtures." The setting times (times to traffic readiness) for Examples 1 to 8 ranged from 47 to 52 minutes. This indicates that the patch materials of these Examples have the advantage of rapid setting.

[0156] The application cases of the trenchless asphalt repair materials prepared in Examples 1 to 8 are as follows: the damaged area of the asphalt pavement with a depth of less than 2 cm is cleaned and coated with emulsified asphalt tack coat oil. The aggregate is first poured into a mixing bucket, 3% water is added, and after stirring evenly to moisten it, the binder is poured in and stirred. The stirring time is controlled within 2 minutes. After stirring evenly, it is poured into the damaged area and smoothed with a scraper. After standing at 25°C for 60 minutes, the repaired pavement is tested. The test results are shown in Table 2.

[0157] Table 2

[0158]

[0159] Among them, the test method for mixability is JTG E20 T0757, and the technical requirement is >120s; the test method for Kent Fort scattering loss is JTG E20 T0733, and the technical requirement is ≤15%; the test method for Marshall stability is JTG E20T0709, and the technical requirement is >20KN; the test method for wet wheel abrasion value (immersion in water for 1h (25℃)) is JTG E20 T0752, and the technical requirement is ≤400g / m 2 .

[0160] From the data in Table 2, we can see that:

[0161] The repair material of this embodiment can meet the traffic performance requirements after being used for trenchless repair of roadbed potholes.

[0162] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A trenchless rapid asphalt repair material, characterized in that: Including binder and aggregate; The binder comprises, by weight, 80 to 100 parts of SBS modified emulsified asphalt, 10 to 15 parts of an anti-cracking modifier, 0.8 to 1 part of a dispersant, and 8 to 10 parts of a reinforcing agent; the anti-cracking modifier is a modified rubber powder blend obtained by sequentially modifying rubber powder with a silane coupling agent and petroleum ether; The aggregate comprises: 0.3 to 1 parts of basalt fiber, 4.5 to 9 parts of powder, 75 to 90 parts of crushed stone, and 5.2 to 15 parts of lignin-based boric acid functionalized carbon nanotubes; the lignin-based boric acid functionalized carbon nanotubes are obtained by modifying lignin with boric acid functionalized carbon nanotubes, and the boric acid functionalized carbon nanotubes are obtained by reacting oxidized carbon nanotubes with 3-aminophenylboronic acid monohydrate.

2. The trenchless rapid asphalt repair material according to claim 1, characterized in that: The preparation process of the modified rubber powder blending liquid is as follows: The rubber powder is pretreated so that its surface contains active groups that can react with the silane coupling agent; the pretreated rubber powder is blended with the silane coupling agent for modification and then dried to obtain modified rubber powder; the modified rubber powder is blended with petroleum ether to obtain the modified rubber powder blending liquid.

3. The trenchless rapid asphalt repair material according to claim 2, characterized in that: The process of pre-treating the rubber powder includes soaking, grinding and drying with a sodium hypochlorite solution.

4. The trenchless rapid asphalt repair material according to claim 2, characterized in that: The mass percentage of the petroleum ether to the modified rubber powder is 1:(3-10).

5. The trenchless rapid asphalt repair material according to claim 4, characterized in that: The mass percentage of the petroleum ether to the modified rubber powder is 1:(5-6).

6. The trenchless rapid asphalt repair material according to claim 2, characterized in that: Nano-silicon dioxide is added during the blending of the modified rubber powder and the petroleum ether, and the nano-silicon dioxide accounts for 5 to 8% of the modified rubber powder in terms of mass percentage.

7. The trenchless rapid asphalt repair material according to claim 1, characterized in that: The preparation process of the lignin-based boric acid functionalized carbon nanotubes is as follows: The carbon nanotubes are subjected to oxidation purification treatment, and then the oxidized and purified carbon nanotubes are dispersed in water to form an aqueous solution; a protective agent and a cross-linking agent are then added in sequence and stirred, and 3-aminophenylboronic acid monohydrate is then added and stirred to react to obtain boric acid functionalized carbon nanotubes; The boric acid functionalized carbon nanotubes are dispersed in an organic solvent, diphenylmethane-4,4'-diisocyanate is added, and the mixture is stirred under a nitrogen atmosphere. Then, lignin and a catalyst are added and stirred for reaction to obtain the lignin-based boric acid functionalized carbon nanotubes.

8. The trenchless rapid asphalt repair material according to claim 7, characterized in that: The oxidant used in the oxidation purification treatment includes nitric acid; the protective agent includes N-hydroxysuccinimide; the cross-linking agent includes 1-ethyl-(3-dimethylaminopropyl)carbodiimide; and the catalyst includes dibutyltin dilaurate.

9. The trenchless rapid asphalt repair material according to claim 7, characterized in that: The process of oxidation purification is: The carbon nanotubes are dispersed in an oxidant, and then reflux-heated at 140-150° C. After the reflux-heating is completed, the mixture is cooled and centrifuged to obtain a precipitate.

10. The trenchless rapid asphalt repair material according to claim 7, characterized in that: The process of dispersing the boric acid functionalized carbon nanotubes into the organic solvent is as follows: Ultrasonicate at 450-500°C for 40-60 minutes.

11. A trenchless rapid asphalt repair material according to any one of claims 1 to 10, characterized in that: The dispersant includes at least one of polyvinyl alcohol and polyacrylic acid.

12. A trenchless rapid asphalt repair material according to any one of claims 1 to 10, characterized in that: The reinforcing agent includes a waterborne epoxy resin.

13. A trenchless rapid asphalt repair material according to any one of claims 1 to 10, characterized in that: The material of the crushed stone includes at least one of basalt, limestone and granite; the powder includes at least one of mineral powder, talcum powder and calcium bicarbonate powder.

14. A trenchless rapid asphalt repair material according to any one of claims 1 to 10, characterized in that: The maximum nominal particle size of the crushed stone is determined based on the repair thickness, and the maximum nominal particle size is 1 / 3 to 1 of the repair thickness.

15. The method for preparing a trenchless rapid asphalt repair material according to any one of claims 1 to 14, characterized in that: preparing the binder and the aggregate respectively; The preparation process of the binder is as follows: Add the anti-cracking modifier to the SBS modified emulsified asphalt at 30-60°C, and stir at 400-800 rpm for 30-40 minutes; then add the dispersant and the reinforcing agent, and stir at 300-600 rpm for 10-15 minutes; The preparation process of the aggregate is as follows: The basalt fiber, the powder, the crushed stone and the lignin-based boric acid functionalized carbon nanotubes are mixed uniformly.

16. Use of the trenchless rapid asphalt repair material according to any one of claims 1 to 14 in repairing roadbed potholes, characterized in that: After adding water to the aggregate and stirring to moisten it, add the binder and stir for 2 to 3 minutes. Then, directly pour the mixed trenchless rapid asphalt repair material into the pit and smooth it.

17. The use according to claim 16, characterized in that The mass ratio of the binder to the aggregate is (10-20): (80-90); in terms of mass percentage, water accounts for 3-5% of the aggregate.

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