Asphalt mixture resistant to high impact loads and method for producing same

Abstract

The present application relates to a kind of asphalt mixture and its preparation method of anti strong impact load.The existing asphalt mixture cannot meet the use demand of special site such as airport in anti strong impact load aspect at present.The asphalt mixture of the present application includes SBS modified asphalt, nano SiO2, coarse texture three-dimensional snowflake-like particle, aggregate, and the coarse texture three-dimensional snowflake-like particle is the particle obtained by 3D printing mode with polyurethane fiber / ultra-high molecular weight polyethylene composite fiber as raw material.The coarse texture three-dimensional snowflake-like particle obtained by 3D printing mode is mixed in the asphalt mixture, and the particle is distributed in three-dimensional mode inside asphalt concrete, and different size particles are compatible with each other, can effectively maintain the internal void grading and three-dimensional form of void of asphalt mixture, delay the change process of internal void of mixture, so that asphalt mixture shows good impact deformation resistance.

Description

Technical Field

[0001] The present invention relates to the technical field of asphalt mixture manufacturing, and in particular to an asphalt mixture capable of resisting strong impact loads and a preparation method thereof. Background Art

[0002] Asphalt concrete pavement has the characteristics of strong adaptability to geological conditions, easy maintenance, smoothness, comfort, and low noise. The use of asphalt concrete cover can effectively reinforce old cement concrete pavement and restore its performance. Therefore, asphalt concrete pavement is increasingly used in airport construction.

[0003] However, with the annual increase in airport aircraft traffic and the proportion of heavy aircraft types, existing asphalt concrete pavements have shown insufficient impact resistance, leading to frequent asphalt concrete pavement damage. Therefore, it is necessary to develop asphalt mixtures that are superior to existing materials in terms of resistance to strong impact loads to meet the needs of special sites such as airports. Summary of the Invention

[0004] The purpose of the present invention is to provide an asphalt mixture resistant to strong impact loads and a preparation method thereof, so as to solve the shortcomings of existing asphalt materials in resisting strong impact loads.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] An asphalt mixture resistant to strong impact loads, comprising the following components in parts by weight:

[0007] SBS modified asphalt 4.5-6.5 parts;

[0008] 1.0 part of nano-SiO2;

[0009] 4-8 parts of coarse textured three-dimensional snowflake-shaped particles;

[0010] Aggregate 92.5-94.5 parts;

[0011] The coarse-textured three-dimensional snowflake-shaped particles are particles obtained by 3D printing using polyurethane fiber / ultra-high molecular weight polyethylene composite fiber as raw materials.

[0012] Furthermore, the aggregate includes 1# coarse aggregate, 2# coarse aggregate, 3# fine aggregate and mineral powder, and the mixing mass ratio is (40-45): (30-35): (15-20): (8-11);

[0013] The 1# coarse aggregate is basalt with an average diameter of 11-16 mm;

[0014] The 2# coarse aggregate is basalt with an average diameter of 6-11 mm;

[0015] The 3# fine aggregate is basalt with an average diameter of 4-6 mm;

[0016] The mineral powder is finely ground basalt with an average diameter of less than 0.075 mm.

[0017] In another aspect, a method for preparing an asphalt mixture resistant to strong impact loads is provided, wherein the method is used to prepare the asphalt mixture, comprising:

[0018] Prepare polyurethane fiber / ultra-high molecular weight polyethylene composite fiber and obtain coarse-textured three-dimensional snowflake-like particles through 3D printing;

[0019] SBS modified asphalt, nano-SiO2, and aggregate are mixed and blended, and coarse-textured three-dimensional snowflake-shaped particles of different particle sizes are added in batches during the mixing process.

[0020] Furthermore, polyurethane fiber / ultra-high molecular weight polyethylene composite fiber is prepared, and coarse textured three-dimensional snowflake-shaped particles are obtained by 3D printing, including:

[0021] The polyurethane fiber is mixed with the spinning oil, and the mixture is continuously stirred and dispersed to obtain a polyurethane fiber mixed solution;

[0022] The powder of ultra-high molecular weight polyethylene is mixed with spinning oil, stirred and dispersed evenly in a swelling kettle, and heated to obtain a spinning swelling solution;

[0023] The polyurethane fiber mixture and the spinning swelling liquid are injected into the twin-screw extruder at the same time and fully mixed to form a uniform fluid;

[0024] The fluid is heated and passes through a distribution plate, a filter, and a spinneret to form polyurethane fiber / ultra-high molecular weight polyethylene composite nascent fibers;

[0025] The polyurethane fiber / ultra-high molecular weight polyethylene composite spun fibers are stress-balanced and neatly arranged on a cluster frame. A hydrocarbon cleaning agent is used to remove the spinning oil from the composite spun fibers. The hydrocarbon cleaning agent is then evaporated at low temperature to remove the hydrocarbon cleaning agent. The fibers are then drawn through a drafting hot box and subjected to four-stage drawing to obtain polyurethane fiber / ultra-high molecular weight polyethylene composite fibers.

[0026] The polyurethane fiber / ultra-high molecular weight polyethylene composite fiber was treated with silane coupling agent KH-550, mixed with ABS resin, and made into filament for 3D printing on a wire drawing machine;

[0027] Polyurethane fiber / ultra-high molecular weight polyethylene composite fiber was printed into particles with coarse textured three-dimensional snowflake shape using a fused deposition modeling 3D printer.

[0028] Furthermore, the mixing mass ratio of the polyurethane fiber to the spinning oil is (1.5-6.5):100;

[0029] The mixing mass ratio of ultra-high molecular weight polyethylene powder to spinning oil is (9.2-9.8):100, and the temperature is raised to 120-125° C. during the stirring process.

[0030] Furthermore, when the polyurethane fiber mixed solution and the spinning swelling solution are simultaneously injected into the twin-screw extruder, the mixing mass ratio of the polyurethane fiber to the ultra-high molecular weight polyethylene is controlled to be (1-5): (95-99) by flow control.

[0031] Furthermore, the fluid temperature is increased from 110-120°C to 275-295°C.

[0032] Furthermore, the stress balancing time of the polyurethane fiber / ultra-high molecular weight polyethylene composite nascent fiber is 36-48 hours;

[0033] The temperature of the drawing through the drawing hot box is 130-135℃.

[0034] Furthermore, the mixing mass ratio of the polyurethane fiber / ultra-high molecular weight polyethylene composite fiber to the ABS resin is (20-30):(70-80).

[0035] Furthermore, SBS modified asphalt, nano-SiO2, and aggregate are mixed and mixed, and coarse textured three-dimensional snowflake-shaped particles of different particle sizes are added in batches during the mixing process, including;

[0036] Heat the SBS modified asphalt in an oven at 160°C until it is molten and keep it warm for later use;

[0037] Heat the aggregate at 180℃ for more than 5h in advance;

[0038] Aggregate and nano-SiO2 were mixed in a mixing pot at 180°C for 20 seconds, and then coarse-textured three-dimensional snowflake-shaped particles with particle sizes of 5 mm, 10 mm, and 15 mm were added respectively, and mixed for 20 seconds each time. The ratio of the three coarse-textured three-dimensional snowflake-shaped particles with the three particle sizes was (45-50): (30-35): (25-15). Then, the insulated SBS modified asphalt was added and mixed for 90 to 95 seconds to prepare an asphalt mixture.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] The present invention incorporates coarse-textured three-dimensional snowflake-shaped particles obtained by 3D printing into the asphalt mixture. The particles are distributed in a three-dimensional manner inside the asphalt concrete. Particles of different sizes are compatible with each other, which can effectively maintain the internal void grading and three-dimensional shape of the asphalt mixture, delay the change process of the internal voids of the mixture, and thus make the asphalt mixture show better resistance to impact deformation.

[0041] The raw material for printing the coarse-textured three-dimensional snowflake-shaped particles of the present invention comprises ultra-high molecular weight polyethylene (UHMWPE). Due to the extremely high molecular weight, extremely long molecular chains and high entanglement between the chains, the impact strength of UHMWPE exceeds 158 kJ / m 2 , combined with polyurethane fiber, the material has excellent impact resistance and wear resistance, and has excellent properties such as tensile strength, low density, non-water absorption, and high toughness. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, without paying any creative work, they can also obtain drawings of other embodiments based on these drawings.

[0043] Figure 1 It is a coarse textured three-dimensional snowflake-like particle. DETAILED DESCRIPTION

[0044] To facilitate understanding of the present invention, the present invention will be described more fully below with reference to the accompanying drawings. The accompanying drawings illustrate preferred embodiments of the present invention. However, the present invention may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the present disclosure.

[0045] In the description of this patent, it is to be understood that all technical and scientific terms used have the same meaning as those commonly understood by those skilled in the art to which this patent belongs. When there is a contradiction, the definitions in this specification shall prevail. Unless otherwise specified, the technical means used in the examples are conventional means well known to those skilled in the art, the reagents used in the examples are commercially available products, and the devices used in the examples are existing devices. The limitation of the means, reagents or devices cannot be understood as a limitation of this patent, and the means, reagents or devices of the same type that solve the same technical problems are all within the scope of protection of this patent.

[0046] In the description of this patent, it should be understood that when an amount, concentration, or other value or parameter is expressed as a range, a preferred range, or a range defined by a series of upper preferred values ​​and lower preferred values, this should be understood to specifically disclose all ranges formed by any pairing of any upper range limit or preferred value with any lower range limit or preferred value, regardless of whether the range is disclosed separately. When a numerical range is described herein, unless otherwise stated, the range is intended to include its end values ​​and all integers and fractions within the range.

[0047] In the description of this patent, it should be understood that multiple steps are involved in the description of the method, which should not be understood as a limitation on the order of the method steps. Technical solutions obtained by simply changing the order of the steps when solving the same technical problem are also within the scope of protection of this patent.

[0048] The present invention provides an asphalt mixture resistant to strong impact loads, suitable for use in places with extremely high requirements for strong impact load resistance, such as airports, and can be used for pavement cover construction and pavement reinforcement structure construction. Specifically, the asphalt mixture includes the following components in parts by weight:

[0049] SBS modified asphalt 4.5-6.5 parts;

[0050] 1.0 part of nano-SiO2;

[0051] 4-8 parts of coarse textured three-dimensional snowflake-shaped particles;

[0052] Aggregate 92.5-94.5 parts.

[0053] in:

[0054] The coarse-textured three-dimensional snowflake-shaped particles are obtained by 3D printing using polyurethane fiber / ultra-high molecular weight polyethylene composite fiber as raw materials.

[0055] The aggregates include 1# coarse aggregate, 2# coarse aggregate, 3# fine aggregate and mineral powder, and the mixing mass ratio is (40-45): (30-35): (15-20): (8-11). 1# coarse aggregate is basalt with an average diameter of 11-16mm, 2# coarse aggregate is basalt with an average diameter of 6-11mm, 3# fine aggregate is basalt with an average diameter of 4-6mm, and mineral powder is finely ground basalt with an average diameter of less than 0.075mm.

[0056] The method for preparing the above-mentioned asphalt mixture resistant to strong impact loads comprises the following steps:

[0057] S1: Prepare polyurethane fiber / ultra-high molecular weight polyethylene composite fiber and obtain coarse textured three-dimensional snowflake-shaped particles through 3D printing. Specifically including:

[0058] S101: Mixing polyurethane fibers with spinning oil, continuously stirring and dispersing them evenly to prevent sedimentation of the polyurethane fibers due to their high density, to obtain a polyurethane fiber mixture. The polyurethane fibers have a diameter of 3.5-7 μm and a length of 0.1-0.5 mm. The mass ratio of the polyurethane fibers to the spinning oil is (1.5-6.5):100.

[0059] S102: Mix the ultra-high molecular weight polyethylene powder with the spinning oil, stir and disperse them evenly in a swelling kettle, and heat to obtain a spinning swelling solution. The ultra-high molecular weight polyethylene powder density is 0.920-0.964 g / cm 3 The particle size is 125 μm. The mass ratio of ultra-high molecular weight polyethylene powder to spinning oil is (9.2-9.8):100, and the temperature is raised to 120-125° C. during stirring.

[0060] S103: The polyurethane fiber mixture and the spinning swelling solution are simultaneously injected into a twin-screw extruder, and the mixing and stirring functions of the twin-screw extruder are utilized to fully mix them into a uniform fluid. During the injection process, the flow rate is controlled to maintain a mass ratio of polyurethane fiber to ultra-high molecular weight polyethylene of (1-5): (95-99).

[0061] S104: The fluid temperature is raised from 110-120°C to 275-295°C, and passes through a distribution plate, a filter, and a spinneret to form polyurethane fiber / ultra-high molecular weight polyethylene composite nascent fibers;

[0062] S105: The polyurethane fiber / ultra-high molecular weight polyethylene composite spun fibers are subjected to stress balancing for 36-48 hours and are neatly arranged on a clustering frame. A hydrocarbon cleaning agent is used to remove the spinning oil from the composite spun fibers. The hydrocarbon cleaning agent is then removed by low-temperature volatilization. The fibers are then drawn through a 130-135°C drawing hot box and subjected to four stages of drawing to obtain polyurethane fiber / ultra-high molecular weight polyethylene composite fibers.

[0063] S106: The polyurethane fiber / ultra-high molecular weight polyethylene composite fiber is treated with a silane coupling agent KH-550, mixed with ABS resin, and formed into filament for 3D printing on a wire drawing machine. The mixing mass ratio of the polyurethane fiber / ultra-high molecular weight polyethylene composite fiber to the ABS resin is (20-30):(70-80).

[0064] S107: Printing polyurethane fiber / ultra-high molecular weight polyethylene composite fiber into particles with a coarse textured three-dimensional snowflake shape by using a fused deposition modeling (FDM) printer, such as Figure 1 The coarse-textured, three-dimensional snowflake-shaped particles come in three sizes: 5mm, 10mm, and 15mm in diameter.

[0065] S2: Mix SBS modified asphalt, nano-SiO2, and aggregate and mix them. During the mixing process, coarse textured three-dimensional snowflake-shaped particles of different particle sizes are added in batches, including;

[0066] S201: Heat the SBS modified asphalt in an oven at 160°C until it is molten and keep it warm for later use;

[0067] S202: preheating the aggregate at 180°C for more than 5 hours;

[0068] S203: Aggregate and nano-SiO2 are mixed in a mixing pot at 180°C for 20 seconds, and then coarse-textured three-dimensional snowflake-shaped particles with particle sizes of 5mm, 10mm, and 15mm are added respectively, and the mixing is carried out for 20 seconds each time. The ratio of the three types of coarse-textured three-dimensional snowflake-shaped particles is (45-50): (30-35): (25-15). Then, the heat-insulated SBS modified asphalt is added and the mixing is continued for 90-95 seconds to prepare an asphalt mixture.

[0069] In this method, the mixing process is different from that of ordinary asphalt concrete. Coarse-textured three-dimensional snowflake-shaped particles of different particle sizes are 3D printed, and the mixing ratio of particles of different particle sizes is different. Secondly, each grade of particles is added in batches at different mixing stages. Small-size particles should be added first for mixing, and then large-size particles are added, so as to play the role of skeleton support of large-size particles and local entanglement of small-size particles.

[0070] Example 1:

[0071] The asphalt mixture comprises the following components in parts by weight:

[0072] 6.5 parts of SBS modified asphalt;

[0073] 1.0 part of nano-SiO2;

[0074] 8 parts of coarse textured three-dimensional snowflake-shaped particles;

[0075] 94.5 parts of aggregate.

[0076] in:

[0077] The coarse-textured three-dimensional snowflake-shaped particles are obtained by 3D printing using polyurethane fiber / ultra-high molecular weight polyethylene composite fiber as raw materials.

[0078] The aggregates include 1# coarse aggregate, 2# coarse aggregate, 3# fine aggregate and mineral powder, with a mixing mass ratio of (40-45):35:20:11. 1# coarse aggregate is basalt with an average diameter of 11-16mm, 2# coarse aggregate is basalt with an average diameter of 6-11mm, 3# fine aggregate is basalt with an average diameter of 4-6mm, and mineral powder is finely ground basalt with an average diameter of less than 0.075mm.

[0079] The method for preparing the above-mentioned asphalt mixture resistant to strong impact loads comprises the following steps:

[0080] S1: Prepare polyurethane fiber / ultra-high molecular weight polyethylene composite fiber and obtain coarse textured three-dimensional snowflake-shaped particles through 3D printing. Specifically including:

[0081] S101: Mixing polyurethane fibers with spinning oil, continuously stirring and dispersing them evenly to prevent sedimentation of the polyurethane fibers due to their high density, to obtain a polyurethane fiber mixture. The polyurethane fibers have a diameter of 3.5-7 μm and a length of 0.1-0.5 mm. The mass ratio of the polyurethane fibers to the spinning oil is 6.5:100.

[0082] S102: Mix the ultra-high molecular weight polyethylene powder with the spinning oil, stir and disperse them evenly in a swelling kettle, and heat to obtain a spinning swelling solution. The ultra-high molecular weight polyethylene powder density is 0.920-0.964 g / cm 3 The particle size is 125 μm. The mass ratio of the ultra-high molecular weight polyethylene powder to the spinning oil is 9.8:100, and the temperature is raised to 125°C during the stirring process.

[0083] S103: The polyurethane fiber mixture and the spinning swelling solution are simultaneously injected into a twin-screw extruder, where they are thoroughly mixed into a uniform fluid using the mixing and stirring functions of the twin-screw extruder. During the injection process, the flow rate is controlled to maintain a mass ratio of polyurethane fiber to ultra-high molecular weight polyethylene of 5:99.

[0084] S104: The fluid temperature is raised from 120°C to 295°C, and passes through a distribution plate, a filter, and a spinneret to form polyurethane fiber / ultra-high molecular weight polyethylene composite nascent fibers;

[0085] S105: The polyurethane fiber / ultra-high molecular weight polyethylene composite spun fibers are subjected to 48 hours of stress balancing and neatly arranged on a clustering frame. A hydrocarbon cleaning agent is used to remove the spinning oil from the composite spun fibers. The hydrocarbon cleaning agent is then removed by low-temperature volatilization. The fibers are then drawn through a 135°C drawing hot box and subjected to four stages of drawing to obtain polyurethane fiber / ultra-high molecular weight polyethylene composite fibers.

[0086] S106: The polyurethane fiber / ultra-high molecular weight polyethylene composite fiber is treated with a silane coupling agent KH-550, mixed with ABS resin, and formed into filament for 3D printing on a wire drawing machine. The mass ratio of the polyurethane fiber / ultra-high molecular weight polyethylene composite fiber to the ABS resin is 30:80.

[0087] S107: Printing polyurethane fiber / ultra-high molecular weight polyethylene composite fiber into particles with a coarse textured three-dimensional snowflake shape by using a fused deposition modeling (FDM) printer, such as Figure 1 The coarse-textured, three-dimensional snowflake-shaped particles come in three sizes: 5mm, 10mm, and 15mm in diameter.

[0088] S2: Mix SBS modified asphalt, nano-SiO2, and aggregate and mix them. During the mixing process, coarse textured three-dimensional snowflake-shaped particles of different particle sizes are added in batches, including;

[0089] S201: Heat the SBS modified asphalt in an oven at 160°C until it is molten and keep it warm for later use;

[0090] S202: preheating the aggregate at 180°C for more than 5 hours;

[0091] S203: Aggregate and nano-SiO2 are mixed in a mixing pot at 180°C for 20 seconds, and then coarse-textured three-dimensional snowflake-shaped particles with particle sizes of 5mm, 10mm, and 15mm are added respectively, and mixed for 20 seconds each time. The ratio of the three coarse-textured three-dimensional snowflake-shaped particles with three particle sizes is 50:35:15. Then, the insulated SBS modified asphalt is added and mixing is continued for 95 seconds to prepare an asphalt mixture.

[0092] Example 2:

[0093] The asphalt mixture comprises the following components in parts by weight:

[0094] 4.5 parts of SBS modified asphalt;

[0095] 1.0 part of nano-SiO2;

[0096] 4 parts of coarse textured three-dimensional snowflake-shaped particles;

[0097] 92.5 parts of aggregate.

[0098] in:

[0099] The coarse-textured three-dimensional snowflake-shaped particles are obtained by 3D printing using polyurethane fiber / ultra-high molecular weight polyethylene composite fiber as raw materials.

[0100] The aggregates include 1# coarse aggregate, 2# coarse aggregate, 3# fine aggregate and mineral powder, with a mixing mass ratio of 40:30:15:8. 1# coarse aggregate is basalt with an average diameter of 11-16mm, 2# coarse aggregate is basalt with an average diameter of 6-11mm, 3# fine aggregate is basalt with an average diameter of 4-6mm, and mineral powder is finely ground basalt with an average diameter of less than 0.075mm.

[0101] The method for preparing the above-mentioned asphalt mixture resistant to strong impact loads comprises the following steps:

[0102] S1: Prepare polyurethane fiber / ultra-high molecular weight polyethylene composite fiber and obtain coarse textured three-dimensional snowflake-shaped particles through 3D printing. Specifically including:

[0103] S101: Mixing polyurethane fibers with spinning oil, continuously stirring and dispersing them evenly to prevent sedimentation of the polyurethane fibers due to their high density, to obtain a polyurethane fiber mixture. The polyurethane fibers have a diameter of 3.5-7 μm and a length of 0.1-0.5 mm. The mass ratio of the polyurethane fibers to the spinning oil is 1.5:100.

[0104] S102: Mix the ultra-high molecular weight polyethylene powder with the spinning oil, stir and disperse them evenly in a swelling kettle, and heat to obtain a spinning swelling solution. The ultra-high molecular weight polyethylene powder density is 0.920-0.964 g / cm 3 The particle size is 125 μm. The mixing mass ratio of ultra-high molecular weight polyethylene powder to spinning oil is 9.2:100, and the temperature is raised to 120°C during the stirring process.

[0105] S103: The polyurethane fiber mixture and the spinning swelling solution are simultaneously injected into a twin-screw extruder, where they are thoroughly mixed into a uniform fluid using the extruder's mixing and stirring functions. During the injection process, the flow rate is controlled to maintain a mass ratio of polyurethane fiber to ultra-high molecular weight polyethylene of 1:95.

[0106] S104: The fluid temperature is raised from 110°C to 275°C, and passes through a distribution plate, a filter, and a spinneret to form polyurethane fiber / ultra-high molecular weight polyethylene composite nascent fibers;

[0107] S105: The polyurethane fiber / ultra-high molecular weight polyethylene composite spun fibers are subjected to 36 hours of stress balancing and are neatly arranged on a cluster rack. A hydrocarbon cleaning agent is used to remove the spinning oil from the composite spun fibers. The hydrocarbon cleaning agent is then removed by low-temperature volatilization. The fibers are then drawn through a 130°C drawing hot box and subjected to four stages of drawing to obtain polyurethane fiber / ultra-high molecular weight polyethylene composite fibers.

[0108] S106: The polyurethane fiber / ultra-high molecular weight polyethylene composite fiber is treated with a silane coupling agent KH-550, mixed with ABS resin, and formed into filament for 3D printing on a wire drawing machine. The mass ratio of the polyurethane fiber / ultra-high molecular weight polyethylene composite fiber to the ABS resin is 20:70.

[0109] S107: Printing polyurethane fiber / ultra-high molecular weight polyethylene composite fiber into particles with a coarse textured three-dimensional snowflake shape by using a fused deposition modeling (FDM) printer, such as Figure 1 The coarse-textured, three-dimensional snowflake-shaped particles come in three sizes: 5mm, 10mm, and 15mm in diameter.

[0110] S2: Mix SBS modified asphalt, nano-SiO2, and aggregate and mix them. During the mixing process, coarse textured three-dimensional snowflake-shaped particles of different particle sizes are added in batches, including;

[0111] S201: Heat the SBS modified asphalt in an oven at 160°C until it is molten and keep it warm for later use;

[0112] S202: preheating the aggregate at 180°C for more than 5 hours;

[0113] S203: Aggregate and nano-SiO2 are mixed in a mixing pot at 180°C for 20 seconds, and then coarse-textured three-dimensional snowflake-shaped particles with particle sizes of 5mm, 10mm, and 15mm are added respectively, and mixed for 20 seconds each time. The ratio of the three coarse-textured three-dimensional snowflake-shaped particles with three particle sizes is 45:30:25. Then, the insulated SBS modified asphalt is added and mixing is continued for 90 seconds to prepare an asphalt mixture.

[0114] Example 3:

[0115] The asphalt mixture comprises the following components in parts by weight:

[0116] 5.5 parts of SBS modified asphalt;

[0117] 1.0 part of nano-SiO2;

[0118] 6 parts of coarse textured three-dimensional snowflake-shaped particles;

[0119] 93.5 parts of aggregate.

[0120] in:

[0121] The coarse-textured three-dimensional snowflake-shaped particles are obtained by 3D printing using polyurethane fiber / ultra-high molecular weight polyethylene composite fiber as raw materials.

[0122] The aggregates include 1# coarse aggregate, 2# coarse aggregate, 3# fine aggregate and mineral powder, with a mixing mass ratio of 42:32:17:9. 1# coarse aggregate is basalt with an average diameter of 11-16mm, 2# coarse aggregate is basalt with an average diameter of 6-11mm, 3# fine aggregate is basalt with an average diameter of 4-6mm, and mineral powder is finely ground basalt with an average diameter of less than 0.075mm.

[0123] The method for preparing the above-mentioned asphalt mixture resistant to strong impact loads comprises the following steps:

[0124] S1: Prepare polyurethane fiber / ultra-high molecular weight polyethylene composite fiber and obtain coarse textured three-dimensional snowflake-shaped particles through 3D printing. Specifically including:

[0125] S101: Mixing polyurethane fibers with spinning oil, continuously stirring and dispersing them evenly to prevent sedimentation of the polyurethane fibers due to their high density, to obtain a polyurethane fiber mixture. The polyurethane fibers have a diameter of 3.5-7 μm and a length of 0.1-0.5 mm. The mass ratio of the polyurethane fibers to the spinning oil is 4:100.

[0126] S102: Mix the ultra-high molecular weight polyethylene powder with the spinning oil, stir and disperse them evenly in a swelling kettle, and heat to obtain a spinning swelling solution. The ultra-high molecular weight polyethylene powder density is 0.920-0.964 g / cm 3 The particle size is 125 μm. The mass ratio of the ultra-high molecular weight polyethylene powder to the spinning oil is 9.5:100, and the temperature is raised to 122°C during the stirring process.

[0127] S103: The polyurethane fiber mixture and the spinning swelling solution are simultaneously injected into a twin-screw extruder, where they are thoroughly mixed into a uniform fluid using the extruder's mixing and stirring functions. During the injection process, the mass ratio of the polyurethane fiber to the ultra-high molecular weight polyethylene is controlled at 3:97 by flow control.

[0128] S104: The fluid temperature is raised from 115°C to 285°C, and passes through a distribution plate, a filter, and a spinneret to form polyurethane fiber / ultra-high molecular weight polyethylene composite nascent fibers;

[0129] S105: The polyurethane fiber / ultra-high molecular weight polyethylene composite spun fibers are subjected to 42 hours of stress balancing and neatly arranged on a cluster frame. A hydrocarbon cleaning agent is used to remove the spinning oil from the composite spun fibers. The hydrocarbon cleaning agent is then removed by low-temperature volatilization. The fibers are then drawn through a 132°C drawing hot box and subjected to four stages of drawing to obtain polyurethane fiber / ultra-high molecular weight polyethylene composite fibers.

[0130] S106: The polyurethane fiber / ultra-high molecular weight polyethylene composite fiber is treated with a silane coupling agent KH-550, mixed with ABS resin, and formed into filament for 3D printing on a wire drawing machine. The mass ratio of the polyurethane fiber / ultra-high molecular weight polyethylene composite fiber to the ABS resin is 25:75.

[0131] S107: Printing polyurethane fiber / ultra-high molecular weight polyethylene composite fiber into particles with a coarse textured three-dimensional snowflake shape by using a fused deposition modeling (FDM) printer, such as Figure 1 The coarse-textured, three-dimensional snowflake-shaped particles come in three sizes: 5mm, 10mm, and 15mm in diameter.

[0132] S2: Mix SBS modified asphalt, nano-SiO2, and aggregate and mix them. During the mixing process, coarse textured three-dimensional snowflake-shaped particles of different particle sizes are added in batches, including;

[0133] S201: Heat the SBS modified asphalt in an oven at 160°C until it is molten and keep it warm for later use;

[0134] S202: preheating the aggregate at 180°C for more than 5 hours;

[0135] S203: Aggregate and nano-SiO2 were mixed in a mixing pot at 180°C for 20 seconds, and then coarse-textured three-dimensional snowflake-shaped particles with particle sizes of 5 mm, 10 mm, and 15 mm were added respectively, and mixed for 20 seconds each time. The ratio of the three coarse-textured three-dimensional snowflake-shaped particles with the three particle sizes was 47:32:20. Then, the insulated SBS modified asphalt was added and mixed for another 92 seconds to prepare an asphalt mixture.

[0136] Comparative Example:

[0137] The hot mix asphalt mixture is prepared according to the preparation method of AC hot mix asphalt mixture in the "Highway Asphalt Pavement Design Specifications".

[0138] In the present invention, ultra-high molecular weight polyethylene is polyethylene with an average molecular weight of more than 1.5 million. The high degree of entanglement of the molecular chain makes the ultra-high molecular weight polyethylene particularly excellent in impact resistance. Compared with other engineering plastics, the impact strength of ultra-high molecular weight polyethylene exceeds 158KJ / m 2, and at the same time possesses excellent properties such as wear resistance, tensile strength, low density, non-water absorption, and high toughness. The coarse-textured three-dimensional snowflake-shaped particles incorporated into the asphalt mixture of the present invention are 3D printed with fibers made of polyurethane fibers, ultra-high molecular weight polyethylene, and ABS resin. The material itself has extremely high impact resistance and has a rich microscopic three-dimensional structure, which delays the change process of the internal voids of the mixture and gives the asphalt mixture ultra-high impact resistance. The impact resistance of asphalt concrete with added polyurethane fiber / ultra-high molecular weight polyethylene composite fiber was tested by a drop hammer impact test device, where the drop hammer mass level was 0.8 kg and the impact height was 400 mm. The test results are shown in Table 1.

[0139] Table 1

[0140] Example 1 Example 2 Example 3 Comparative Example Impact energy (J) 91.8 77.4 83.6 67.1

[0141] The test results show that the impact resistance of asphalt concrete with the addition of polyurethane fiber / ultra-high molecular weight polyethylene composite fiber is improved by 15.4%-36.8% compared with ordinary asphalt concrete. This is of great significance in places such as airports where high resistance to strong impact loads is required. It can significantly extend the service life of the pavement, reduce pavement diseases, and thus effectively improve the safety of aircraft takeoff and landing.

[0142] The above examples are used to illustrate the present invention, which are only used to help understand the present invention and are not intended to limit the present invention. Those skilled in the art can make several simple deductions, modifications or substitutions based on the concept of the present invention.

Claims

1. A method for preparing an asphalt mixture resistant to strong impact loads, characterized in that: The asphalt mixture is suitable for the construction of airport pavement covers and airport pavement reinforcement structures, and includes the following components in parts by weight: SBS modified asphalt 4.5-6.5 parts; 1.0 part of nano-SiO2; 4-8 parts of coarse textured three-dimensional snowflake-shaped particles; Aggregate 92.5-94.5 parts; The coarse-textured three-dimensional snowflake-shaped particles are obtained by 3D printing using polyurethane fiber / ultra-high molecular weight polyethylene composite fiber as raw materials. The particle sizes include 5 mm, 10 mm, and 15 mm. The mixing ratio of the three particle sizes of the coarse-textured three-dimensional snowflake-shaped particles is (45-50): (30-35): (25-15). When mixing, small-size particles are added first, followed by large-size particles. The large-size particles serve as a skeleton support, and the small-size particles are locally entangled, thereby delaying the change of the internal voids of the mixture. The method for preparing the asphalt mixture comprises the following steps: Prepare polyurethane fiber / ultra-high molecular weight polyethylene composite fiber and obtain coarse-textured three-dimensional snowflake-like particles through 3D printing; SBS modified asphalt, nano-SiO2, and aggregate are mixed and blended, and coarse-textured three-dimensional snowflake-shaped particles of different sizes are added in batches during the mixing process; in: Preparation of polyurethane fiber / ultra-high molecular weight polyethylene composite fiber, and obtaining the coarse textured three-dimensional snowflake-shaped particles by 3D printing, comprising: The polyurethane fiber is mixed with the spinning oil, and the mixture is continuously stirred and dispersed to obtain a polyurethane fiber mixed solution; The powder of ultra-high molecular weight polyethylene is mixed with spinning oil, stirred and dispersed evenly in a swelling kettle, and heated to obtain a spinning swelling solution; The polyurethane fiber mixture and the spinning swelling liquid are injected into the twin-screw extruder at the same time and fully mixed to form a uniform fluid; The fluid is heated and passes through a distribution plate, a filter, and a spinneret to form polyurethane fiber / ultra-high molecular weight polyethylene composite nascent fibers; The polyurethane fiber / ultra-high molecular weight polyethylene composite spun fibers are stress-balanced and neatly arranged on a cluster frame. A hydrocarbon cleaning agent is used to remove the spinning oil from the composite spun fibers. The hydrocarbon cleaning agent is then evaporated at low temperature to remove the hydrocarbon cleaning agent. The fibers are then drawn through a drafting hot box and subjected to four-stage drawing to obtain polyurethane fiber / ultra-high molecular weight polyethylene composite fibers. The polyurethane fiber / ultra-high molecular weight polyethylene composite fiber was treated with silane coupling agent KH-550, mixed with ABS resin, and made into filament for 3D printing on a wire drawing machine; The polyurethane fiber / ultra-high molecular weight polyethylene composite fiber was printed into particles with a coarse texture and three-dimensional snowflake shape using a fused deposition modeling 3D printer; SBS modified asphalt, nano-SiO2, and aggregate are mixed and blended. During the mixing process, coarse-textured three-dimensional snowflake-shaped particles of different sizes are added in batches, including: The SBS modified asphalt was heated in an oven at 160°C until it was molten and kept warm for later use. The aggregate was preheated at 180°C for more than 5 hours. The aggregate and nano-SiO2 were mixed in a mixing pot at 180°C for 20 seconds. Coarse-textured three-dimensional snowflake-shaped particles with particle sizes of 5mm, 10mm, and 15mm were then added, mixing for 20 seconds each time. The SBS modified asphalt that had been kept warm was then added and mixing continued for 90-95 seconds to prepare an asphalt mixture. The aggregate includes 1# coarse aggregate, 2# coarse aggregate, 3# fine aggregate and mineral powder, and the mixing mass ratio is (40-45): (30-35): (15-20): (8-11); The 1# coarse aggregate is basalt with an average diameter of 11-16 mm; The 2# coarse aggregate is basalt with an average diameter of 6-11 mm; The 3# fine aggregate is basalt with an average diameter of 4-6 mm; The mineral powder is finely ground basalt with an average diameter of less than 0.075 mm.

2. The method according to claim 1, wherein: The mixing mass ratio of polyurethane fiber and spinning oil is (1.5-6.5):100; The mixing mass ratio of ultra-high molecular weight polyethylene powder and spinning oil is (9.2-9.8):100, and the temperature is raised to 120-125°C during the stirring process.

3. The method according to claim 2, wherein: When the polyurethane fiber mixture and the spinning swelling solution are simultaneously injected into the twin-screw extruder, the mixing mass ratio of the polyurethane fiber to the ultra-high molecular weight polyethylene is controlled to be (1-5): (95-99) by flow control.

4. The method according to claim 3, wherein: The fluid temperature is increased from 110-120°C to 275-295°C.

5. The method according to claim 4, characterized in that: The stress equilibrium time of polyurethane fiber / ultra-high molecular weight polyethylene composite primary fiber is 36-48h; The temperature of the drawing through the drawing hot box is 130-135℃.

6. The method according to claim 5, characterized in that: The mixing mass ratio of the polyurethane fiber / ultra-high molecular weight polyethylene composite fiber to the ABS resin is (20-30): (70-80).

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