Preparation and application of a plugging agent for oil drilling

Abstract

This invention discloses the preparation and application of a plugging agent for oil drilling, relating to the field of oil drilling technology. The invention utilizes a blend of silicone rubber, silicone resin, and wollastonite whiskers. The resin, in conjunction with the wollastonite whiskers, acts as a reinforcing and toughening agent in the silicone rubber, serving as a softening material during high-temperature operation. Simultaneously, the silicone rubber and silicone resin can bond with the formation at high temperatures, stabilizing the wellbore and improving the strength of the plugging layer. Then, a hollow fiber-like material is prepared using an extrusion deposition printing method. Part of this material is sheared to obtain hollow particles, thereby improving the flexibility of the elastomer. Subsequently, the hollow fiber-like material and some of the hollow particle material are densified. The wollastonite whiskers promote hardening, resulting in a rigid filler. The hardened hollow fiber-like material and the asphalt softening particles have a "stretcher" effect, thereby improving the pressure-bearing capacity and high-temperature resistance of the plugging layer.

Description

Technical Field

[0001] This invention relates to the field of oil drilling technology, specifically to the preparation and application of a plugging agent for oil drilling. Background Technology

[0002] As the world's energy exploration shifts from conventional oil and gas exploration to unconventional exploration, unconventional oil and gas resources such as shale gas are receiving increasing attention. Shale gas refers to the storage and preservation of biochemically derived gas, thermogenic gas, or a mixture of both, in dark mudstone or high-carbon mudstone rich in organic matter, where organic matter exists in adsorbed and free states within the matrix pores and fractures. According to data from the U.S. Energy Information Administration in 2013, global shale gas reserves are abundant, approaching 1013 trillion cubic meters. China possesses the world's largest shale gas reserves, with explored reserves reaching 130 trillion cubic meters and recoverable reserves reaching 20 trillion cubic meters.

[0003] Against the backdrop of complex geological conditions and the ever-expanding scale of shale gas extraction, well leakage has become one of the most common complex situations encountered during development. Well leakage can induce complex situations such as pressure drop, wellbore instability, collapse, and blowouts, not only affecting drilling speed but also causing huge economic losses, and placing more stringent requirements on drilling fluid technology. For shale formations, water-based drilling fluids have the advantages of low cost, wide application, mature technology, and low reservoir contamination. However, their main disadvantages include easy hydration and swelling, and sticking issues. Compared to water-based drilling fluids, oil-based drilling fluids hardly react with water-sensitive formation minerals, have advantages such as strong inhibition, high lubrication coefficient, and good thermal stability, which are conducive to maintaining wellbore stability and are an important means of drilling various complex formations such as mudstone, shale, and salt gypsum layers. Summary of the Invention

[0004] The purpose of this invention is to provide a preparation and application of a plugging agent for oil drilling, in order to solve the problems existing in the prior art.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a plugging agent for oil drilling, comprising the following preparation steps:

[0006] (1) Mix polyvinyl alcohol and deionized water, heat to 60-80℃, stir at 100-200 rpm for 3 hours, cool to 30-50℃, add methacrylate, butyl acrylate, methyl phenyl silicone resin, methyl trimethoxysilane, dispersible wollastonite whiskers, surfactant, and photoinitiator, heat to 70-80℃, stir at 500 rpm for 6-8 hours, cool to room temperature, filter, take the solid, wash with deionized water 3-8 times, dry at 50℃ for 8 hours, then mix with methyl vinyl silicone rubber, heat to 230-300℃, stir at 120 rpm for 20 minutes, and finally 3D print in a nitrogen atmosphere to obtain a hollow fiber-like product.

[0007] (2) The simulated hollow fiber was sheared to obtain elastic hollow particles with a particle size of 100μm.

[0008] (3) Dry the simulated hollow fiber and the elastic hollow particles at 60-100℃ for 9 hours, then keep them at 200-400℃ for 1-2 hours, and finally mix the two to obtain the rigid filler.

[0009] (4) The elastic hollow particles, rigid fillers, and SOLTEX softened asphalt particles with a particle size of 20-100μm are compounded to obtain a plugging agent for oil drilling.

[0010] Further, the dispersible wollastonite whiskers described in step (1) are obtained by mixing wollastonite whiskers with a 0.5wt% KH-570 aqueous solution, stirring at 500-1000 rpm for 10-30 min, filtering, taking the solid, washing it with deionized water 3-8 times, and drying it at 50℃ for 8 h.

[0011] Furthermore, the surfactant in step (1) is hexadecyltrimethylammonium bromide.

[0012] Furthermore, the photoinitiator in step (1) is ethyl 2,4,6-trimethylbenzoyl phosphate.

[0013] Furthermore, in step (1), the mass ratio of polyvinyl alcohol, deionized water, methacrylate, butyl acrylate, methylphenyl silicone resin, methyltrimethoxysilane, dispersible wollastonite whiskers, surfactant, photoinitiator, and methyl vinyl silicone rubber is 1:100:5~20:20:10~30:0.05~0.1:0.01:0.001:0.01:20~50.

[0014] Furthermore, the 3D printing process parameters in step (1) are as follows: the light source is a UV-LED lamp, the light source wavelength is 405nm, and the light intensity is 1.2mW / cm². 2 .

[0015] Furthermore, the outer diameter of the simulated hollow fiber in step (1) is 100 μm and the inner diameter is 30 to 70 μm.

[0016] Furthermore, in step (3), the mass ratio of the simulated hollow fiber to the elastic hollow particles is 2:1 to 2.

[0017] Furthermore, in step (4), the mass ratio of the elastic hollow particles, rigid fillers, and SOLTEX softened asphalt particles with a particle size of 20–100 μm is 8–20:6–15:4.

[0018] Furthermore, the application of the aforementioned oil drilling plugging agent in plugging leaks during the oil drilling process.

[0019] Compared with existing technologies, the beneficial effects achieved by this invention are as follows: This invention utilizes a blend of silicone rubber, silicone resin, and wollastonite whiskers to create an elastic filler material. The resin acts as a bridging agent between the macromolecules of silicone rubber, and works synergistically with the wollastonite whiskers to reinforce and toughen the material. During high-temperature operation, it can act as a softening material, softening the silicone rubber and subsequently adsorbing oil and swelling. Simultaneously, the silanol groups of both materials condense with the silanol groups on the rock surface to form silicon-oxygen-silicon bonds. Non-ionic groups adsorb onto the rock surface through hydrogen bonding, and positively charged cationic groups tightly adsorb onto the negatively charged formation rock through electrostatic interactions, thus cementing with the formation, stabilizing the wellbore, and improving the strength of the sealing layer. This allows the plugging agent to achieve high-temperature resistance and high mechanical properties. Subsequently, it is deposited through extrusion. The printing process creates continuous filaments, while simultaneously preparing simulated hollow fibers through track design. Part of these fibers are sheared to obtain hollow particles, thereby improving the flexibility of the elastomer and enhancing the sealing properties of the sealant. The simulated hollow fibers and some hollow particle materials are then densified. The silica in the wollastonite whiskers acts as a nucleating agent for the silicone resin, promoting the formation of silica in the matrix and thus achieving hardening. The hardened hollow particles act as rigid fillers, bridging the sealant and enhancing its sealing effect. Under high temperatures, the hardened simulated hollow fibers and asphalt softening particles act as "bracing" agents, forming a relatively stable "strong chain network" with the elastic hollow particles and rigid fillers in the microcrack or pore sealing layer, thereby improving the pressure-bearing capacity and high-temperature resistance of the sealing layer. Detailed Implementation

[0020] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0021] To more clearly illustrate the method provided by the present invention, the following embodiments are provided in detail. The test methods for various indicators of the plugging agent for oil drilling prepared in the following embodiments are as follows:

[0022] Leakage plugging performance: Examples and comparative examples of the same size were used. The LHKYDL-3 high temperature and high pressure leakage plugging test device was used. 30-mesh quartz sand was used as the evaluation sand bed to simulate the leakage channel. 25g of the sample was added to 500mL of oil-based drilling fluid and stirred evenly. Then it was poured into the water loss cylinder of the leakage plugging device. A movable piston was placed on top of it. Then the cylinder cap was tightened and sealed. The temperature of the water loss cylinder was 150℃. After standing for 12h, water was injected using a large displacement horizontal flow pump to pressurize. The pressurization rate was controlled. The pressure was increased by 1MPa every 10min until it reached 7MPa. The degree of leakage at the sand bed outlet was observed and recorded.

[0023] High temperature resistance: Take samples of the same size as the example and comparative examples, mix them with an appropriate amount of 0# diesel oil, let them stand at 150℃ for 6 hours, pour off the excess oil, and test the elongation of the samples.

[0024] Oil absorption: Take samples of the same size as the example and comparative examples, mix them with an appropriate amount of 0# diesel oil, let them stand for 6 hours, pour out the excess oil, and measure the oil absorption ratio of the samples.

[0025] Example 1

[0026] (1) Mix wollastonite whiskers with 0.5wt% KH-570 aqueous solution, stir at 500rpm for 10min, filter, take the solid, wash with deionized water 3 times, and dry at 50℃ for 8h to obtain dispersed wollastonite whiskers; mix polyvinyl alcohol and deionized water, heat to 60℃, stir at 100rpm for 3h, cool to 30℃, and add methacrylate, butyl acrylate, methylphenyl silicone resin, methyltrimethoxysilane, dispersed wollastonite whiskers, and hexadecyltrimethyl methacrylate. Ammonium bromide and ethyl 2,4,6-trimethylbenzoyl phosphate were heated to 70°C and stirred at 500 rpm for 6 hours. The mixture was then cooled to room temperature, filtered, and the solid was washed three times with deionized water and dried at 50°C for 8 hours. It was then mixed with methyl vinyl silicone rubber, heated to 230°C, and stirred at 120 rpm for 20 minutes. Finally, the mixture was 3D printed under a nitrogen atmosphere. The process parameters were: UV-LED light source, wavelength 405 nm, and light intensity 1.2 mW / cm². 2 The resulting simulated hollow fiber has an outer diameter of 100 μm and an inner diameter of 30 μm; the mass ratio of the polyvinyl alcohol, deionized water, methacrylate, butyl acrylate, methylphenyl silicone resin, methyltrimethoxysilane, dispersible wollastonite whiskers, hexadecyltrimethylammonium bromide, ethyl 2,4,6-trimethylbenzoyl phosphate, and methyl vinyl silicone rubber is 1:100:5:20:10:0.05:0.01:0.001:0.01:20.

[0027] (2) The simulated hollow fiber was sheared to obtain elastic hollow particles with a particle size of 100μm.

[0028] (3) The simulated hollow fiber and the elastic hollow particles are dried at 60°C for 9 hours, then kept at 200°C for 1 hour, and finally mixed to obtain a rigid filler; the mass ratio of the simulated hollow fiber and the elastic hollow particles is 2:1.

[0029] (4) The elastic hollow particles, rigid filler and SOLTEX softened asphalt particles with a particle size of 20 μm are compounded to obtain a plugging agent for oil drilling; the mass ratio of the elastic hollow particles, rigid filler and SOLTEX softened asphalt particles with a particle size of 20 μm is 8:6:4.

[0030] Example 2

[0031] (1) Mix wollastonite whiskers with 0.5wt% KH-570 aqueous solution, stir at 800rpm for 20min, filter, take the solid, wash with deionized water 5 times, and dry at 50℃ for 8h to obtain dispersed wollastonite whiskers; mix polyvinyl alcohol and deionized water, heat to 70℃, stir at 150rpm for 3h, cool to 40℃, and add methacrylate, butyl acrylate, methylphenyl silicone resin, methyltrimethoxysilane, dispersed wollastonite whiskers, and hexadecyltrimethyl methacrylate. Ammonium bromide and ethyl 2,4,6-trimethylbenzoyl phosphate were heated to 75°C and stirred at 500 rpm for 7 hours. The mixture was then cooled to room temperature, filtered, and the solid was washed five times with deionized water and dried at 50°C for 8 hours. It was then mixed with methyl vinyl silicone rubber, heated to 270°C, and stirred at 120 rpm for 20 minutes. Finally, the mixture was 3D printed under a nitrogen atmosphere. The process parameters were: UV-LED light source, wavelength 405 nm, and light intensity 1.2 mW / cm². 2 The resulting simulated hollow fiber has an outer diameter of 100 μm and an inner diameter of 50 μm; the mass ratio of the polyvinyl alcohol, deionized water, methacrylate, butyl acrylate, methylphenyl silicone resin, methyltrimethoxysilane, dispersible wollastonite whiskers, hexadecyltrimethylammonium bromide, ethyl 2,4,6-trimethylbenzoyl phosphate, and methyl vinyl silicone rubber is 1:100:13:20:20:0.08:0.01:0.001:0.01:35.

[0032] (2) The simulated hollow fiber was sheared to obtain elastic hollow particles with a particle size of 100μm.

[0033] (3) The simulated hollow fiber and the elastic hollow particles are dried at 80℃ for 9 hours, then kept at 300℃ for 1.5 hours, and finally mixed to obtain a rigid filler; the mass ratio of the simulated hollow fiber and the elastic hollow particles is 2:1.5.

[0034] (4) The elastic hollow particles, rigid filler and SOLTEX softened asphalt particles with a particle size of 70 μm are compounded to obtain a plugging agent for oil drilling; the mass ratio of the elastic hollow particles, rigid filler and SOLTEX softened asphalt particles with a particle size of 70 μm is 14:9:4.

[0035] Example 3

[0036] (1) Mix wollastonite whiskers with 0.5wt% KH-570 aqueous solution, stir at 1000rpm for 30min, filter, take the solid, wash with deionized water 8 times, and dry at 50℃ for 8h to obtain dispersed wollastonite whiskers; mix polyvinyl alcohol and deionized water, heat to 80℃, stir at 200rpm for 3h, cool to 50℃, and add methacrylate, butyl acrylate, methylphenyl silicone resin, methyltrimethoxysilane, dispersed wollastonite whiskers, and hexadecyltrimethyl methacrylate. Ammonium bromide and ethyl 2,4,6-trimethylbenzoyl phosphate were heated to 80°C and stirred at 500 rpm for 8 hours. The mixture was then cooled to room temperature, filtered, and the solid was washed eight times with deionized water and dried at 50°C for 8 hours. It was then mixed with methyl vinyl silicone rubber, heated to 300°C, and stirred at 120 rpm for 20 minutes. Finally, the mixture was 3D printed under a nitrogen atmosphere. The process parameters were: UV-LED light source, wavelength 405 nm, and light intensity 1.2 mW / cm². 2 The resulting simulated hollow fiber has an outer diameter of 100 μm and an inner diameter of 70 μm; the mass ratio of the polyvinyl alcohol, deionized water, methacrylate, butyl acrylate, methylphenyl silicone resin, methyltrimethoxysilane, dispersible wollastonite whiskers, hexadecyltrimethylammonium bromide, ethyl 2,4,6-trimethylbenzoyl phosphate, and methyl vinyl silicone rubber is 1:100:20:20:30:0.1:0.01:0.001:0.01:50.

[0037] (2) The simulated hollow fiber was sheared to obtain elastic hollow particles with a particle size of 100μm.

[0038] (3) The simulated hollow fiber and the elastic hollow particles are dried at 100℃ for 9 hours, then kept at 400℃ for 2 hours, and finally mixed to obtain a rigid filler; the mass ratio of the simulated hollow fiber and the elastic hollow particles is 2:2.

[0039] (4) The elastic hollow particles, rigid filler and SOLTEX softened asphalt particles with a particle size of 100μm are compounded to obtain a plugging agent for oil drilling; the mass ratio of the elastic hollow particles, rigid filler and SOLTEX softened asphalt particles with a particle size of 100μm is 20:15:4.

[0040] Comparative Example 1

[0041] The difference between Comparative Example 1 and Example 2 lies in step (1). Step (1) is changed as follows: Polyvinyl alcohol and deionized water are mixed, heated to 70°C, stirred at 150 rpm for 3 hours, cooled to 40°C, and methacrylate, butyl acrylate, methylphenyl silicone resin, methyltrimethoxysilane, hexadecyltrimethylammonium bromide, and ethyl 2,4,6-trimethylbenzoyl phosphate are added. The mixture is heated to 75°C, stirred at 500 rpm for 7 hours, cooled to room temperature, filtered, and the solid is washed 5 times with deionized water and dried at 50°C for 8 hours. Then it is mixed with methyl vinyl silicone rubber, heated to 270°C, stirred at 120 rpm for 20 minutes, and finally 3D printed under a nitrogen atmosphere. The process parameters are: the light source is a UV-LED lamp, the light source wavelength is 405 nm, and the light intensity is 1.2 mW / cm². 2 The resulting simulated hollow fiber has an outer diameter of 100 μm and an inner diameter of 50 μm. The mass ratio of the polyvinyl alcohol, deionized water, methacrylate, butyl acrylate, methylphenyl silicone resin, methyltrimethoxysilane, hexadecyltrimethylammonium bromide, ethyl 2,4,6-trimethylbenzoyl phosphate, and methyl vinyl silicone rubber is 1:100:13:20:20:0.08:0.001:0.01:35. The remaining steps are the same as in Example 2.

[0042] Comparative Example 2

[0043] The difference between Comparative Example 2 and Example 2 lies in step (1). Step (1) is changed as follows: Wollastonite whiskers and 0.5wt% KH-570 aqueous solution are mixed, stirred at 800 rpm for 20 min, filtered, the solid is taken, washed 5 times with deionized water, and dried at 50℃ for 8 h to obtain dispersible wollastonite whiskers; polyvinyl alcohol and deionized water are mixed, heated to 70℃, stirred at 150 rpm for 3 h, cooled to 40℃, and methacrylate, butyl acrylate, and methyl methacrylate are added. The mixture consisted of phenyl silicone resin, methyltrimethoxysilane, dispersible wollastonite whiskers, hexadecyltrimethylammonium bromide, and ethyl 2,4,6-trimethylbenzoyl phosphate. The mixture was heated to 75°C, stirred at 500 rpm for 7 hours, cooled to room temperature, filtered, and the solid was washed five times with deionized water and dried at 50°C for 8 hours. Then, it was 3D printed under a nitrogen atmosphere. The process parameters were: UV-LED lamp as the light source, wavelength of 405 nm, and light intensity of 1.2 mW / cm². 2 The resulting simulated hollow fiber has an outer diameter of 100 μm and an inner diameter of 50 μm. The mass ratio of the polyvinyl alcohol, deionized water, methacrylate, butyl acrylate, methylphenyl silicone resin, methyltrimethoxysilane, dispersible wollastonite whiskers, hexadecyltrimethylammonium bromide, and ethyl 2,4,6-trimethylbenzoyl phosphate is 1:100:13:20:20:0.08:0.01:0.001:0.01. The remaining steps are the same as in Example 2.

[0044] Comparative Example 3

[0045] The difference between Comparative Example 3 and Example 2 is that step (3) is omitted, and step (4) is changed to: compounding elastic hollow particles and SOLTEX softened asphalt particles with a particle size of 70μm to obtain a plugging agent for oil drilling; the mass ratio of the elastic hollow particles and SOLTEX softened asphalt particles with a particle size of 70μm is 14:4; the remaining steps are the same as in Example 2.

[0046] Comparative Example 4

[0047] The difference between Comparative Example 4 and Example 2 is that step (4) is different. Step (4) is changed to: combining elastic hollow particles and rigid fillers to obtain a plugging agent for oil drilling; the mass ratio of the elastic hollow particles to the rigid fillers is 14:9; the remaining steps are the same as in Example 2.

[0048] Example of effect

[0049] Table 1 below shows the performance analysis results of the plugging agents for oil drilling using Examples 1 to 3 and Comparative Examples 1 to 4 of the present invention.

[0050] Table 1

[0051] degree of leakage Stretch ratio Oil absorption ratio Example 1 none 5.9 10 Example 2 none 6.7 12 Example 3 none 6.4 11 Comparative Example 1 Linear Leakage 4.1 10 Comparative Example 2 drip 4.2 7 Comparative Example 3 Linear Leakage 4.5 9 Comparative Example 4 Linear Leakage 4.6 9

[0052] A comparison of the experimental results of the embodiments and comparative examples in Table 1 reveals that the present invention utilizes a blend of silicone rubber, silicone resin, and wollastonite whiskers to create an elastic filler material. The resin acts as a bridging agent between the macromolecules of the silicone rubber, and works synergistically with the wollastonite whiskers to reinforce and toughen the material. At high temperatures, it can act as a softening material, adsorbing oil and swelling. Simultaneously, the silanol groups of both silicone rubber and wollastonite condense with the silanol groups on the rock surface to form silicon-oxygen-silicon bonds. Nonionic groups are adsorbed onto the rock surface through hydrogen bonding, and positively charged cationic groups are tightly adsorbed onto the negatively charged formation rock through electrostatic interactions, thus cementing the material with the formation and improving the strength of the sealing layer. This allows the sealing agent to achieve high-temperature resistance and high mechanical properties. The material is then processed through an extrusion deposition printing method. Continuous fine filaments are formed, and hollow fiber-like materials are prepared by designing tracks. Some of these materials are sheared to obtain hollow particles, thereby improving the flexibility of the elastomer and enhancing the sealing performance of the sealant. Then, the hollow fiber-like materials and some hollow particle materials are densified. The silica in the wollastonite whiskers can act as a nucleating agent for the silicone resin, promoting the formation of silica in the matrix and thus achieving hardening. As a rigid filler, it plays a bridging role in the sealant, enhancing the sealing effect. The hardened hollow fiber-like materials and asphalt softening particles have a "stretching" effect at high temperatures, and together with the elastic hollow particles and rigid fillers, they form a relatively stable "strong chain network" in the microcrack or pore sealing layer, thereby improving the pressure resistance and high temperature resistance of the sealing layer.

[0053] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No markings in the claims should be construed as limiting the scope of the claims.

Claims

1. A plugging agent for oil drilling, characterized in that, The preparation steps include the following: (1) Mix polyvinyl alcohol and deionized water, heat to 60~80℃, stir at 100~200rpm for 3h, cool to 30~50℃, add methacrylate, butyl acrylate, methyl phenyl silicone resin, methyl trimethoxysilane, dispersible wollastonite whiskers, surfactant and photoinitiator, heat to 70~80℃, stir at 500rpm for 6~8h, cool to room temperature, filter, take solid, wash with deionized water 3~8 times, dry at 50℃ for 8h, then mix with methyl vinyl silicone rubber, heat to 230~300℃, stir at 120rpm for 20min, and finally 3D print in a nitrogen atmosphere to obtain hollow fiber-like material. (2) The simulated hollow fiber was sheared to obtain elastic hollow particles with a particle size of 100 μm; (3) Dry the simulated hollow fiber and the elastic hollow particles at 60~100℃ for 9h, then keep them at 200~400℃ for 1~2h, and finally mix the two to obtain the rigid filler. (4) The elastic hollow particles, rigid fillers, and SOLTEX softened asphalt particles with a particle size of 20~100μm are compounded to obtain a plugging agent for oil drilling. The dispersible wollastonite whiskers in step (1) are prepared by mixing wollastonite whiskers with a 0.5wt% KH-570 aqueous solution, stirring at 500-1000 rpm for 10-30 min, filtering, taking the solid, washing it with deionized water 3-8 times, and drying it at 50℃ for 8 h. The surfactant mentioned in step (1) is hexadecyltrimethylammonium bromide; The photoinitiator in step (1) is ethyl 2,4,6-trimethylbenzoyl phosphate; The mass ratio of polyvinyl alcohol, deionized water, methacrylate, butyl acrylate, methylphenyl silicone resin, methyltrimethoxysilane, dispersible wollastonite whiskers, surfactant, photoinitiator, and methyl vinyl silicone rubber in step (1) is 1:100:5~20:20:10~30:0.05~0.1:0.01:0.001:0.01:20~50; The 3D printing process parameters in step (1) are as follows: the light source is a UV-LED lamp, the light source wavelength is 405nm, and the light intensity is 1.2mW / cm². 2 ; The outer diameter of the simulated hollow fiber in step (1) is 100 μm and the inner diameter is 30~70 μm; The mass ratio of the simulated hollow fiber and the elastic hollow particles in step (3) is 2:1~2; The mass ratio of the elastic hollow particles, rigid fillers, and SOLTEX softened asphalt particles with a particle size of 20~100μm in step (4) is 8~20:6~15:4.