Trenchless rapid asphalt repairing material as well as preparation method and application thereof

Abstract

The invention relates to the technical field of road repairing materials, and particularly discloses a trenchless rapid asphalt repairing material as well as a preparation method and application thereof. The cementing material comprises the following components in parts by weight: 80-100 parts of SBS modified emulsified asphalt, 10-15 parts of an anti-cracking modifier, 0.8-1 part of a dispersing agent and 8-10 parts of a reinforcing agent; the anti-cracking modifier is a modified rubber powder blending solution obtained by sequentially modifying rubber powder with a silane coupling agent and petroleum ether; the aggregate is prepared from the following components in parts by weight: 0.3 to 1 part of basalt fiber, 4.5 to 9 parts of powder, 75 to 90 parts of gravel 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. The trenchless rapid asphalt repairing material disclosed by the invention has fluidity and strength and can be used for repairing shallow-layer or thin-layer pit slots of a pavement in a trenchless manner.

Description

Technical Field

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

[0002] Asphalt pavement has become the preferred high-grade pavement material in road construction due to its excellent performance. This material is formed by mixing asphalt with mineral materials to form a paving material with high durability. It can not only withstand the frequent use of heavy-duty vehicles and the test of extreme weather, but also the constructed road surface is flat, waterproof, and has a long service life.

[0003] Although asphalt pavement is favored for its easy maintenance and durability, with the increase in traffic volume and vehicle weight, the road surface will inevitably have damages such as cracks and potholes. For crack repair, sealant is usually used for repair, and for pothole repair, the excavation and filling method is usually adopted. Among them, the excavation and filling method is to deeply cut and remove the disease area with potholes, fill it with hot mix or asphalt cold patch material, and compact it with a plate compactor or a roller for repair. Due to the poor fluidity of hot mix asphalt and asphalt cold patch material, for shallow or thin-layer peeling potholes, only by expanding the disease area through excavation can the asphalt mixture be filled into the potholes. This repair method has low efficiency and large resource waste, greatly increasing the cost of road disease treatment and maintenance.

[0004] Emulsified asphalt mixture has good fluidity. In theory, when it is used to repair potholes on asphalt pavement, there is no need to expand the disease area by excavation, and the advantage of its good fluidity can be used to directly fill the repair material containing emulsified asphalt into the potholes for repair. However, if emulsified asphalt is directly used to repair potholes, rapid shaping cannot be achieved, and the initial strength after repair is relatively low, resulting in poor durability, poor compressive resistance, and poor crack resistance in the disease area after repair, and finally leading to cracking problems 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-layer potholes on the road surface in a trenchless manner.

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

[0007] The present invention is achieved by the following technical solutions: A trenchless rapid asphalt repair material, comprising a binder and an 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; The aggregate comprises: 0.3-1 parts 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, and the boric acid functionalized carbon nanotubes are obtained by reacting oxidized carbon nanotubes with 3-aminophenylboric acid monohydrate.

[0008] 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 and wet stones. Although emulsified asphalt can meet the fluidity requirements for trenchless repair of roadbed potholes, the strength after repair is low, which makes the repaired roadbed have poor crack resistance and results in a short service life of the repaired roadbed.

[0009] Compared with conventional emulsified asphalt, the SBS modified emulsified asphalt used in the present invention not only has the advantages of good fluidity, but also has high temperature resistance, durability and crack resistance. Using SBS modified emulsified asphalt as a carrier material of a binder can improve the crack resistance of asphalt repair materials to a certain extent. However, directly using SBS modified emulsified asphalt is also difficult to meet the requirements of roadbed compression resistance. Therefore, when BS modified emulsified asphalt is used to repair shallow or thin potholes on the road surface, the bonding strength of the repair material needs to be further improved.

[0010] The present invention can improve the impact strength of SBS modified emulsified asphalt by adding an anti-cracking modifier, a dispersant and a reinforcing agent into the binder and cooperating with the SBS modified emulsified asphalt, thereby improving its anti-cracking performance. 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.

[0011] 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 cause the opposite effect due to agglomeration. Therefore, the application of rubber powder in SBS modified emulsified asphalt is limited.

[0012] The present invention uses a silane coupling agent to modify rubber powder, which can improve the dispersion performance of rubber powder in SBS modified emulsified asphalt. By blending petroleum ether with the modified rubber powder, the compatibility between the modified rubber powder and SBS modified emulsified asphalt can be improved. That is, the rubber powder of the present invention is added to SBS modified emulsified asphalt in the form of a modified rubber powder blend liquid, which has good compatibility and dispersion with SBS modified emulsified asphalt, realizing the toughening effect of rubber powder on SBS modified emulsified asphalt, and further improving the impact strength and tensile strength of SBS modified emulsified asphalt.

[0013] To improve the tensile strength of the repair material, fibers are usually added to the aggregate. However, when adding fibers alone, the increase in tensile strength is limited. In the present invention, by adding lignin-based boric acid functionalized carbon nanotubes to the aggregate and acting together with basalt fibers, the tensile strength of the repair material can be greatly improved, making the roadbed after repair have a high tensile strength.

[0014] Lignin has the advantage of hardness. Adding lignin to the aggregate can improve the tensile strength of the repair material to a certain extent, but the increase is limited. While lignin modified with carbon nanotubes can further improve the tensile strength of lignin and contribute to improving the impact strength, but the dispersion is poor. Compared with 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 high dispersion performance to achieve the strengthening effect on the repair material.

[0015] In summary, the repair material of the present invention has both fluidity and strength, and can repair shallow or thin-layer potholes on the road surface in a trenchless manner.

[0016] In addition, since the repair material of the present invention repairs shallow or thin-layer potholes on the road surface in a trenchless manner, there is no need to excavate and expand the damaged area. The advantage of its good fluidity can be used to directly fill the repair material into the pothole to achieve repair, and rapid repair can be realized.

[0017] In a preferred embodiment, the preparation process of the modified rubber powder blend liquid is as follows: The rubber powder is pretreated so that its surface contains active groups capable of reacting with the silane coupling agent; the pretreated rubber powder is blended and modified with the silane coupling agent and then dried to obtain modified rubber powder, and the modified rubber powder is blended with petroleum ether to obtain a modified rubber powder blend liquid.

[0018] Blending the modified rubber powder with petroleum ether to obtain a modified rubber powder blend liquid has good compatibility with SBS modified emulsified asphalt. The reason is that they both have a carbon chain structure.

[0019] In a preferred embodiment, the process of pretreating the rubber powder includes wet grinding with a sodium hypochlorite solution and drying.

[0020] In a preferred embodiment, the mass percentage of petroleum ether to modified rubber powder is 1:(3 - 10).

[0021] In a preferred embodiment, the mass percentage of petroleum ether to modified rubber powder is 1:(5 - 6).

[0022] 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, there will be no obvious increase in compatibility.

[0023] In a preferred embodiment, nano - silica is added during the blending process of modified rubber powder and petroleum ether. By mass percentage, nano - silica is 5 - 8% of the modified rubber powder.

[0024] The addition of nano - silica can further improve the compatibility between rubber powder and SBS modified emulsified asphalt.

[0025] In a preferred embodiment, the preparation process of lignin - based boric acid functionalized carbon nanotubes is as follows: The carbon nanotubes are subjected to oxidation and purification treatment, and then the carbon nanotubes after oxidation and purification treatment are dispersed in water to form an aqueous solution; then a protective agent and a cross - linker are added in sequence and stirred, and then 3 - aminophenylboronic acid monohydrate is added and stirred for reaction 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, stirred under a nitrogen atmosphere, and then lignin and a catalyst are added and stirred for reaction to obtain lignin - based boric acid functionalized carbon nanotubes.

[0026] Subjecting the carbon nanotubes to oxidation and purification treatment can not only remove impurities from the carbon nanotubes and increase the purity of the carbon nanotubes, but also change the physical and chemical properties of the carbon nanotubes, enhancing their dispersibility and solubility.

[0027] In a preferred embodiment, the oxidant used in the oxidation and purification treatment includes nitric acid; the protective agent includes N - hydroxysuccinimide; the cross - linker includes 1 - ethyl - (3 - dimethylaminopropyl) carbodiimide; the catalyst includes dibutyltin dilaurate.

[0028] In a preferred embodiment, the process of oxidation and purification treatment is as follows: The carbon nanotubes are dispersed in the oxidant, and then refluxed and heated at 140 - 150 °C. After the reflux heating is completed, cooling and centrifugation are carried out in sequence to obtain a precipitate.

[0029] In a preferred embodiment, the process of dispersing boric acid functionalized carbon nanotubes in an organic solvent is as follows: Ultrasonic treatment is carried out at 450 - 500 °C for 40 - 60 min.

[0030] In a preferred embodiment, the dispersant comprises at least one of polyvinyl alcohol and polyacrylic acid.

[0031] In a preferred embodiment, the reinforcing agent comprises waterborne epoxy resin.

[0032] In a preferred embodiment, the crushed stone comprises hard crushed stone made of materials such as basalt, limestone, granite, etc.; the powder comprises at least one of mineral powder, talc powder, and heavy calcium carbonate powder.

[0033] 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.

[0034] A preparation method of a trenchless rapid asphalt repair material, comprising separately preparing a binder and an aggregate; The preparation process of the binder is as follows: When the SBS modified emulsified asphalt is at 30 - 60 °C, an anti-cracking modifier is added, and it is stirred at a speed of 400 - 800 rmp for 30 - 40 min; then a dispersant and a reinforcing agent are added, and it is stirred at a speed of 300 - 600 rmp for 10 - 15 min; The preparation process of the aggregate is as follows: Stir basalt fiber, powder, crushed stone, and lignin-based boric acid functionalized carbon nanotubes evenly.

[0035] An application of a trenchless rapid asphalt repair material in repairing roadbed potholes. After adding water to the aggregate and stirring until wet, then adding the binder, stirring for 2 - 3 min, and directly pouring the mixed trenchless rapid asphalt repair material into the pothole and leveling it.

[0036] In a preferred embodiment, the mass ratio of the binder to the aggregate is (10 - 20):(80 - 90); by mass percentage, water is 3 - 5% of the aggregate.

[0037] Compared with the prior art, the present invention has the following advantages and beneficial effects: By adding an anti-cracking modifier, a dispersant, and a reinforcing agent to the binder and cooperating with the SBS modified emulsified asphalt, the present invention can significantly improve the impact strength and tensile strength of the repair material; 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. Finally, the repair material has both fluidity and high strength, can repair shallow or thin-layer potholes on the road surface in a trenchless manner, and the repaired road surface has the advantage of long service life due to its high strength. Detailed embodiments

[0038] To make the objectives, technical solutions, and advantages of the present invention more clearly understood, the present invention will be further described in detail below in conjunction with embodiments. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and are not intended to limit the present invention. The following described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0039] In the following description, a large number of specific details are set forth in order to provide a thorough understanding of the present invention. However, it is obvious to those of ordinary skill in the art that the present invention does not have to employ these specific details. In other embodiments, well-known structures, materials, or methods are not specifically described in order to avoid obscuring the present invention. The materials, instruments, and reagents used in the following embodiments, unless otherwise specified, can all be obtained from commercial channels. The technical means used in the embodiments, unless otherwise specified, are all conventional means well-known to those skilled in the art.

[0040] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, "a plurality" means two or more, unless otherwise specifically defined.

[0041] Embodiment: In order to achieve trenchless repair of shallow or thin-layer pothole disease areas on the road surface, a repair material with both fluidity and strength needs to be prepared. A trenchless rapid asphalt repair material includes a binder and an aggregate; the binder and the aggregate are prepared separately and packaged independently, and then mixed in proportion during use.

[0042] By weight, the binder includes: 80-100 parts of SBS modified emulsified asphalt, 10-15 parts of crack resistance modifier, 0.8-1 part of dispersant, and 8-10 parts of enhancer.

[0043] Among them, the SBS modified emulsified asphalt is an existing product purchased from Daozhijian (Shanghai) New Materials Company.

[0044] Among them, the crack resistance modifier is a modified rubber powder blend solution obtained by modifying rubber powder with a silane coupling agent and petroleum ether in sequence. Specifically: The preparation process of the modified rubber powder blend solution is as follows: The rubber powder is pretreated so that its surface contains active groups capable of reacting with the silane coupling agent; the pretreated rubber powder is blended and modified with the silane coupling agent and then dried to obtain modified rubber powder, and the modified rubber powder is blended with petroleum ether to obtain the modified rubber powder blend solution.

[0045] In a specific case, the preparation process of the modified rubber powder blend is as follows: After mixing and wetting rubber powder (styrene-butadiene rubber powder) and sodium hypochlorite solution in a mass ratio of 1:1, wet ball milling and drying are carried out in sequence to make the surface of the rubber powder contain active groups such as hydroxyl groups (-OH); weigh a certain mass of silane coupling agent KH550, use water as a solvent, and prepare a 0.5% KH550 solution; then add the pretreated rubber powder into the silane coupling agent solution and stir evenly. The solid-liquid ratio of the coupling agent modification is 200 g of rubber powder reacting with 2 L of silane coupling agent solution. Finally, place it in a dry environment until the surface of the rubber powder particles is completely dry to obtain modified rubber powder; the silane coupling agent KH550 hydrolyzes in water to produce silanol groups, which react with -OH in the rubber powder, realizing the modification of the rubber powder with the silane coupling agent to improve the dispersibility of the rubber powder in SBS modified emulsified asphalt. Blend the modified rubber powder with petroleum ether for 30 min to obtain a modified rubber powder blend to improve the compatibility of the rubber powder in 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).

[0046] In a preferred case, nano-silica is added during the blending process of the modified rubber powder and petroleum ether. By mass percentage, the nano-silica is 5 - 8% of the modified rubber powder.

[0047] Among them, the dispersant includes at least one of polyvinyl alcohol (CAS#: 9002 - 89 - 5) and polyacrylic acid (CAS#: 9003 - 01 - 4); adding a dispersant is used to improve the dispersion uniformity of the crack resistance modifier and the enhancer in SBS modified emulsified asphalt. Polyvinyl alcohol is purchased from SIGMA-ALDRICH; polyacrylic acid is purchased from Juyu Giant Base New Materials Co., Ltd.

[0048] Among them, the enhancer includes waterborne epoxy resin or waterborne polyurethane. Waterborne epoxy resin or waterborne polyurethane is used to improve the adhesion between the binder and the aggregate, and specifically, waterborne epoxy resin EP137, waterborne polyurethane PU104, etc. can be used.

[0049] By weight, the aggregate includes: 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.

[0050] Among them, the length of the basalt fiber is 3 - 6 mm, the thickness is 0.18 mm, and the surface density is 200 ± 20 g / m 2 .

[0051] Among them, the crushed stones include hard crushed stones made of materials such as basalt, limestone, and granite; the powder materials include at least one of mineral powder, talcum powder, and heavy calcium carbonate powder; the particle size is 200 - 400 mesh.

[0052] Among them, the particle size of the crushed stones is determined based on the size of the pothole depth; during actual use, the corresponding crushed stones can be configured based on the pothole depth. The pothole depth is 1 - 3 times the maximum nominal particle size of the crushed stones. For example, when the pothole depth is 1 cm, the particle size of the crushed stones is 3 - 5 mm.

[0053] Among them, 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: The carbon nanotubes are subjected to oxidation and 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, cooling and centrifugation are carried out in sequence to obtain a precipitate; then the carbon nanotubes after oxidation and purification treatment are dispersed in water to form an aqueous solution; then a protective agent and a cross - linker are added in sequence and stirred, and then 3 - aminophenylboronic acid monohydrate is added, and stirred and reacted to obtain boric acid - functionalized carbon nanotubes; 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: ultrasonic treatment at 450 - 500 °C for 40 - 60 min; after dispersion, diphenylmethane - 4,4'-diisocyanate is added, stirred in a nitrogen atmosphere, and then lignin and a catalyst are added, and stirred and reacted to obtain lignin - based boric acid - functionalized carbon nanotubes.

[0054] In a specific case, the oxidant used in the oxidation and purification treatment is nitric acid; the protective agent is N - hydroxysuccinimide; the cross - linker is 1 - ethyl - (3 - dimethylaminopropyl) carbodiimide; the catalyst is dibutyltin dilaurate.

[0055] In a specific case, the preparation process of the lignin - based boric acid - functionalized carbon nanotubes is as follows: Disperse carbon nanotubes into 30% HNO3, then reflux and heat at 140 °C for 24 h. After the mixed solution cools naturally, centrifuge to obtain a precipitate. Wash the precipitate with deionized water until the pH of the washing solution is 7, and dry the precipitate in an oven for 12 h. Take the dried precipitate and disperse it in deionized water to obtain a mixed solution with a concentration of 1 mg / mL. Add 0.017 g of N-hydroxysuccinimide (CAS: 6066-82-6) to 50 mL of the mixed solution, stir vigorously, then add 0.03 g of 1-ethyl-(3-dimethylaminopropyl)carbodiimide. Continue to stir the mixed solution at room temperature for 1 h, add 0.025 g of 3-aminophenylboronic acid monohydrate, and then stir and react at 30 °C for 24 h. Then wash the precipitate with deionized water several times to obtain boronic acid-functionalized carbon nanotubes.

[0056] Take 5 g of boronic acid-functionalized carbon nanotubes and disperse them into 500 mL of chloroform. Ultrasonicate for 40 min at 500 °C. Add 2 mL of diphenylmethane-4,4'-diisocyanate, and stir for 1 h under a nitrogen atmosphere. Then add 3 g of lignin and 2 drops of dibutyltin dilaurate (CAS#: 77-58-7), and continue to stir for 3 h. Then filter the mixed solution to obtain a precipitate, wash the precipitate with chloroform 3 times, and then dry it under vacuum at 70 °C to obtain lignin-based boronic acid-functionalized carbon nanotubes.

[0057] 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), carbon nanotubes (CAS: 308068-56-6, product number 698849) were all purchased from SIGMA-ALDRICH; For the preparation method of the above trenchless rapid asphalt repair material, prepare the binder and aggregate respectively; The preparation process of the binder is as follows: When the SBS modified emulsified asphalt is at 30 - 60 °C, add the anti-cracking modifier and shear at a speed of 400 - 800 rmp for 30 - 40 min; then add the dispersant and the reinforcing agent and stir at a speed of 300 - 600 rmp for 10 - 15 min.

[0058] In a specific case, heat the SBS modified emulsified asphalt to 60 °C, add the anti-cracking modifier, and stir at a speed of 600 rmp for 30 min; after cooling to 40 °C, add the dispersant and the reinforcing agent and stir at a speed of 400 rmp for 10 min.

[0059] The preparation process of the aggregate is as follows: Mix basalt fiber, powder, gravel and lignin-based boric acid functionalized carbon nanotubes in proportion and stir evenly.

[0060] 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 a crack resistance modifier, a dispersant and a reinforcing agent to the binder and cooperating with the 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 finally the repair material has both fluidity and high strength, can realize the trenchless repair of subgrade potholes, and the subgrade after repair has the advantages of long service life due to its high strength.

[0061] When the trenchless rapid asphalt repair material is applied to repair subgrade potholes, add water to the aggregate and stir to moisten it, then add the binder, stir for 2 - 3 minutes, and directly pour the mixed trenchless rapid asphalt repair material into the pothole and level it.

[0062] Specifically, the mass ratio of the binder to the aggregate is (10 - 20):(80 - 90); by mass percentage, water is 3 - 5% of the aggregate.

[0063] To better illustrate the effect of this embodiment, it is illustrated by the following specific cases.

[0064] Example 1: A trenchless rapid asphalt repair material, comprising a binder and an aggregate; the binder and the aggregate are prepared separately and packaged independently, and then mixed in proportion during use.

[0065] By weight, the binder includes: 100 parts of SBS modified emulsified asphalt, 15 parts of crack resistance modifier, 1 part of dispersant, 10 parts of reinforcing agent; the crack resistance modifier is a modified rubber powder blend obtained by modifying rubber powder with a silane coupling agent and petroleum ether in sequence, and the preparation process of the modified rubber powder blend refers to the above embodiment; By weight, the aggregate includes: 0.5 part of basalt fiber, 8 parts of powder, 83.5 parts of gravel, 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.

[0066] Example 2: This embodiment is based on Example 1, and the difference from Example 1 is that the dosage of each component is different. Specifically: A trenchless rapid asphalt repair material, comprising a binder and an aggregate; By weight, the binder includes: 80 parts of SBS-modified emulsified asphalt, 10 parts of crack resistance modifier, 0.8 parts of dispersant, and 8 parts of reinforcing agent; 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.

[0067] Example 3: This example is based on Example 1. The difference from Example 1 is that the amount of crack resistance modifier is reduced. Specifically: A trenchless rapid asphalt repair material includes a binder and an aggregate; By weight, the binder includes: 100 parts of SBS-modified emulsified asphalt, 10 parts of crack resistance modifier, 1 part of dispersant, and 10 parts of reinforcing agent; By weight, the aggregate includes: 0.5 part of basalt fiber, 8 parts of powder, 83.5 parts of crushed stone, and 8 parts of lignin-based boric acid functionalized carbon nanotubes.

[0068] Example 4: This example is based on Example 1. The difference from Example 1 is that the amount of lignin-based boric acid functionalized carbon nanotubes is reduced. Specifically: A trenchless rapid asphalt repair material includes a binder and an aggregate; By weight, the binder includes: 100 parts of SBS-modified emulsified asphalt, 15 parts of crack resistance modifier, 1 part of dispersant, and 10 parts of reinforcing agent; By weight, the aggregate includes: 0.5 part of basalt fiber, 8 parts of powder, 83.5 parts of crushed stone, and 5 parts of lignin-based boric acid functionalized carbon nanotubes.

[0069] Example 5: This example is based on Example 1. The difference from Example 1 is that the amount of lignin-based boric acid functionalized carbon nanotubes is increased. Specifically: A trenchless rapid asphalt repair material includes a binder and an aggregate; By weight, the binder includes: 100 parts of SBS-modified emulsified asphalt, 15 parts of crack resistance modifier, 1 part of dispersant, and 10 parts of reinforcing agent; By weight, the aggregate includes: 0.5 part of basalt fiber, 8 parts of powder, 83.5 parts of crushed stone, and 10 parts of lignin-based boric acid functionalized carbon nanotubes.

[0070] Example 6: This example is based on Example 1. The difference from Example 1 is that the amount of lignin-based boric acid functionalized carbon nanotubes is increased. Specifically: A trenchless rapid asphalt repair material includes a binder and an aggregate; By weight, the binder includes: 100 parts of SBS-modified emulsified asphalt, 15 parts of crack-resistant modifier, 1 part of dispersant, and 10 parts of reinforcing agent; By weight, the aggregate includes: 0.5 part of basalt fiber, 8 parts of powder, 83.5 parts of crushed stone, and 13 parts of lignin-based boric acid functionalized carbon nanotubes.

[0071] Example 7: This example is based on Example 1. The difference from Example 1 is that the dosage of lignin-based boric acid functionalized carbon nanotubes is increased. Specifically: A trenchless rapid asphalt repair material includes a binder and an aggregate; By weight, the binder includes: 100 parts of SBS-modified emulsified asphalt, 15 parts of crack-resistant modifier, 1 part of dispersant, and 10 parts of reinforcing agent; By weight, the aggregate includes: 0.5 part of basalt fiber, 8 parts of powder, 83.5 parts of crushed stone, and 15 parts of lignin-based boric acid functionalized carbon nanotubes.

[0072] Example 8: This example is based on Example 1. The difference from Example 1 is that: During the preparation of the modified rubber powder blend, nano-silica is added during the blending of the modified rubber powder and petroleum ether. By mass percentage, the nano-silica is 8% of the modified rubber powder.

[0073] Comparative Example 1: This comparative example is based on Example 1. The difference from Example 1 is that the crack-resistant modifier is not contained in the binder.

[0074] A trenchless rapid asphalt repair material includes a binder and an aggregate; By weight, the binder includes: 100 parts of SBS-modified emulsified asphalt, 1 part of dispersant, and 10 parts of reinforcing agent; By weight, the aggregate includes: 0.5 part of basalt fiber, 8 parts of powder, 83.5 parts of crushed stone, and 8 parts of lignin-based boric acid functionalized carbon nanotubes.

[0075] Comparative Example 2: This comparative example is based on Example 1. The difference from Example 1 is that an equal amount of rubber powder is used to replace the crack-resistant modifier in the binder.

[0076] Comparative Example 3: This comparative example is based on Example 1. The difference from Example 1 is that an equal amount of modified rubber powder is used to replace the crack-resistant modifier in the binder.

[0077] Comparative Example 4: This comparative example is based on Example 1, and the difference from Example 1 is that an equal amount of lignin is used to replace the lignin-based boric acid-functionalized carbon nanotubes in the aggregate.

[0078] A trenchless rapid asphalt repair material includes a binder and an aggregate; By weight, the binder includes: 100 parts of SBS-modified emulsified asphalt, 15 parts of crack resistance modifier, 1 part of dispersant, and 10 parts of reinforcing agent; By weight, the aggregate includes: 0.5 part of basalt fiber, 8 parts of powder, 83.5 parts of crushed stone, and 8 parts of lignin.

[0079] Comparative Example 5: This comparative example is based on Example 1, and the difference from Example 1 is that an equal amount of carbon nanotube-modified lignin is used to replace the lignin-based boric acid-functionalized carbon nanotubes in the aggregate.

[0080] The preparation process of carbon nanotube-modified lignin is as follows: Take 5 g of carbon nanotubes and disperse them in 500 mL of chloroform, and ultrasonicate for 40 min at 500 °C; add 2 mL of diphenylmethane-4,4'-diisocyanate, and stir for 1 h under a nitrogen atmosphere; then add 3 g of lignin and 2 drops of dibutyltin dilaurate, and continue to stir for 3 h; then filter the mixed solution to obtain a precipitate, wash the precipitate 3 times with chloroform, and then vacuum dry at 70 °C to obtain carbon nanotube-modified lignin.

[0081] Comparative Example 6: This comparative example is based on Comparative Example 4, and the difference from Comparative Example 4 is that 2 parts of sodium tetraborate are added. Specifically: A trenchless rapid asphalt repair material includes a binder and an aggregate; By weight, the binder includes: 100 parts of SBS-modified emulsified asphalt, 15 parts of crack resistance modifier, 1 part of dispersant, 10 parts of reinforcing agent, and 2 parts of sodium tetraborate; By weight, the aggregate includes: 0.5 part of basalt fiber, 8 parts of powder, 83.5 parts of crushed stone, and 8 parts of lignin.

[0082] The repair materials of Examples 1 - 8 and Comparative Examples 1 - 6 were prepared into specimen pieces in the following manner, and the tensile strength and impact resistance of each test piece were tested. For the tensile strength, it was determined with reference to GB / T 1040.3 - 2006 "Determination of Tensile Properties of Plastics", with a tensile speed of 2 mm / min. 3 specimens were taken for testing in each group, and the results were averaged; for the impact resistance, it was determined with reference to GB / T 1843 - 2008 "Determination of Izod Impact Strength of Plastics". 3 specimens were taken for testing in each group, and the results were averaged. The results are shown in Table 1.

[0083] The preparation process of the test specimen is as follows: After adding water to the aggregate and stirring to moisten it, by mass percentage, the water is 3% of the aggregate; 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, level it, and take out the test specimen after the repair material cures; the mass ratio of the binder to the aggregate is 20:80.

[0084] Table 1 It can be seen from the data in Table 1 that: 1) The impact resistance strength of the repair materials prepared in each embodiment of the present invention is all above 14.0 KJ / m 2 This shows that the anti-cracking modifier obtained by modifying with rubber powder in the present invention utilizes the elasticity of the rubber powder to achieve the toughening effect on the repair material, thereby improving its anti-cracking performance and being able to withstand stronger impact forces.

[0085] 2) The anti-cracking modifier has a greater impact on the impact resistance 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 its impact resistance strength. Although rubber powder can improve the toughness of asphalt, whether it is modified and the modification method will affect its effect of improving the impact resistance strength of the material. This is because of the compatibility and dispersion between rubber powder and emulsified asphalt.

[0086] 3) The 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. By adding lignin-based boric acid functionalized carbon nanotubes to the aggregate in the present invention, the tensile strength of the repair material can be significantly improved. Adding lignin and carbon nanotubes to modify lignin, compared with lignin-based boric acid functionalized carbon nanotubes, the tensile strength of the repair material decreases.

[0087] 4) By adding the anti-cracking modifier to the binder and adding lignin-based boric acid functionalized carbon nanotubes to the aggregate in the present invention, the tensile strength and impact resistance strength of the repair material can be improved. And the SBS modified emulsified asphalt has the advantage of good fluidity. Therefore, the repair material prepared in the present invention can be applied to the trenchless repair of subgrade pits.

[0088] In addition, take the trenchless asphalt repair materials prepared in Examples 1 to 8, and refer to JTG E20 - 211 "Test Procedures for Highway Asphalt and Asphalt Mixtures" for testing. The test is carried out at 25°C. The setting times (trafficable times) of Examples 1 to 8 are distributed from 47 to 52 minutes. That is, the repair material of this embodiment has the advantage of fast setting speed.

[0089] Application cases of the trenchless asphalt repair materials prepared in Examples 1 to 8: For the asphalt pavement disease area with a disease depth within 2 cm, clean it, apply emulsified asphalt tack coat. First, pour the aggregate into the mixing bucket, add 3% water, stir evenly until wet, then pour in the binder and stir. Control the stirring time at 2 min. After stirring evenly, pour it into the disease area and level it with a spatula. After standing at 25°C for 60 min, test the repaired pavement. The test results are shown in Table 2.

[0090] Table 2 Among them, for the mixable time, the test method is JTG E20 T0757, and the technical requirement is >120 s; for the Cantabro abrasion loss, the test method is JTG E20 T0733, and the technical requirement is ≤15%; for the Marshall stability, the test method is JTG E20 T0709, and the technical requirement is >20 KN; for the wet wheel abrasion value (immersed in water for 1 h (25°C)), the test method is JTG E20 T0752, and the technical requirement is ≤400 g / m 2 。

[0091] As can be seen from the data in Table 2: After the repair material of this example is used for trenchless repair of subgrade potholes, it can meet the traffic performance requirements.

[0092] The specific embodiments described above have further detailed the purpose, technical solutions and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A trenchless rapid asphalt repair material, characterized in that, It includes a binder and aggregates; By weight, the binder includes: 80 - 100 parts of SBS modified emulsified asphalt, 10 - 15 parts of crack resistance modifier, 0.8 - 1 part of dispersant, and 8 - 10 parts of reinforcing agent; the crack resistance modifier is a modified rubber powder blend solution obtained by modifying rubber powder with silane coupling agent and petroleum ether in sequence; The aggregates include: 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, 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 blend solution is as follows: The rubber powder is pretreated so that its surface contains active groups capable of reacting with the silane coupling agent; after the pretreated rubber powder is blended and modified with the silane coupling agent and dried, modified rubber powder is obtained, and the modified rubber powder is blended with the petroleum ether to obtain the modified rubber powder blend solution.

3. The trenchless rapid asphalt repair material according to claim 2, characterized in that, The process of pretreating the rubber powder includes wet grinding, drying with sodium hypochlorite solution.

4. The trenchless rapid asphalt repair material according to claim 2, wherein 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, wherein, During the blending process of the modified rubber powder and the petroleum ether, nano-silica is added. By mass percentage, the nano-silica is 5 - 8% of the modified rubber powder.

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

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

9. The trenchless rapid asphalt repair material according to claim 7, characterized in that, The process of oxidation and purification treatment is as follows: The carbon nanotubes are dispersed in the oxidant, and then refluxed and heated at 140 - 150 °C. After the reflux heating is completed, cooling and centrifugation are carried out in sequence to obtain a precipitate.

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

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

13. A trenchless rapid asphalt repair material according to any one of claims 1-10, 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, talc powder, and heavy calcium carbonate powder.

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

15. The preparation method of the trenchless rapid asphalt repair material according to any one of claims 1-14, characterized in that, Prepare the binder and the aggregate respectively; The preparation process of the binder is as follows: When the SBS modified emulsified asphalt is at 30 - 60 °C, add the crack resistance modifier and stir at a speed of 400 - 800 rmp for 30 - 40 min; then add the dispersant and the enhancer and stir at a speed of 300 - 600 rmp for 10 - 15 min; The preparation process of the aggregate is as follows: Stir the basalt fiber, the powder, the crushed stone and the lignin-based boric acid functionalized carbon nanotube evenly.

16. The application of the trenchless rapid asphalt repair material according to any one of claims 1-14 in repairing roadbed potholes, characterized in that, After adding water to the aggregate and stirring to moisten it, then add the binder and stir for 2 - 3 min, and directly pour the mixed trenchless rapid asphalt patching material into the pothole and level it.

17. The application according to claim 16, wherein The mass ratio of the binder to the aggregate is (10 - 20):(80 - 90); calculated by mass percentage, water is 3 - 5% of the aggregate.

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