High-bearing-capacity permeable asphalt pavement and construction method thereof

Abstract

The invention discloses a high-bearing-capacity permeable asphalt pavement and a construction method thereof, relates to the technical field of asphalt pavements, and aims to solve the problem of insufficient bearing capacity of the permeable asphalt pavement. According to the technical scheme, the pavement structure is characterized by comprising a roadbed layer and a broken stone hardcore, the roadbed layer is laid at the bottom of a pavement, the broken stone hardcore is arranged above the roadbed layer, and the broken stone hardcore is formed by laying a plurality of first coarse aggregates; the bearing and water storage composite layer is arranged above the broken stone hardcore, the bearing and water storage composite layer comprises a high-toughness permeable middle layer and a wear-resisting and noise-reducing surface layer, and the high-toughness permeable middle layer is arranged below the wear-resisting and noise-reducing surface layer. According to the invention, the high-toughness permeable middle layer adopts a rubber material I compounded and modified by SBS and rubber powder, and is doped with polyester fibers and basalt fibers to form a three-dimensional network structure, so that the high-toughness permeable middle layer has high toughness to cope with heavy load, and the wear-resistant noise-reducing surface layer adopts a high-viscosity rubber material II and hydrophobic rubber particles, so that the durability of wear-resistant and permeable functions is ensured.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of asphalt pavement, more particularly, it relates to a high-load-bearing water-permeable asphalt pavement and a construction method thereof. BACKGROUND

[0002] Traditional cement concrete pavement covers a large area of urban surface, causing a series of ecological and environmental problems, such as frequent waterlogging, insufficient groundwater recharge, and intensified heat island effect. Therefore, as a key technology for the construction of sponge cities, water-permeable asphalt pavement has been widely valued because it can quickly infiltrate rainwater into the ground, effectively supplement groundwater, alleviate urban waterlogging, and improve the urban thermal environment.

[0003] In order to maintain a high connected porosity, traditional water-permeable asphalt pavement usually uses single-size coarse aggregate and a high asphalt content, which leads to an optimization space for the skeleton interlocking structure of the mixture and the thickness of the asphalt film. Under the repeated action of heavy-load vehicles, the pavement is prone to early damage such as aggregate spalling, scattering, and potholes, and its fatigue resistance and load-bearing capacity cannot meet the requirements of high-stress areas such as bus lanes, intersections, and parking lots.

[0004] Therefore, a new solution is needed to solve this problem. SUMMARY

[0005] In view of the deficiencies of the prior art, the present application aims to provide a high-load-bearing water-permeable asphalt pavement and a construction method thereof, which has the advantage of improving load-bearing capacity.

[0006] The above technical purpose of the present application is achieved by the following technical solution: a high-load-bearing water-permeable asphalt pavement, comprising: a subgrade layer and a gravel cushion layer, the subgrade layer is laid at the bottom of the pavement, the gravel cushion layer is arranged above the subgrade layer, and the gravel cushion layer is made of a plurality of coarse aggregates laid; a load-bearing water storage composite layer arranged above the gravel cushion layer, the load-bearing water storage composite layer comprises a high-toughness water-permeable middle layer and a wear-resistant noise-reducing surface layer, and the high-toughness water-permeable middle layer is arranged below the wear-resistant noise-reducing surface layer; a buffer layer arranged between the gravel cushion layer and the high-toughness water-permeable middle layer; The high-toughness water-permeable middle layer is made of a rubber material one, reinforcing fibers and coarse aggregate two, the rubber material one is made of high-elasticity asphalt modified by adding SBS modifier and rubber powder, the rubber powder is made by grinding waste tire rubber, the reinforcing fibers are made of polyester fibers or basalt short fibers or a combination of both, the reinforcing fibers are uniformly dispersed in the rubber material one, the content of the reinforcing fibers is 0.2-0.4% of the coarse aggregate two, the reinforcing fibers form a three-dimensional network structure in the rubber material one, and the thickness of the high-toughness water-permeable middle layer is 40-60mm. The wear-resistant noise-reducing surface layer comprises a rubber material two, hydrophobic rubber particles and coarse aggregate three, the rubber material two is high-viscosity modified asphalt with a dynamic viscosity of not less than 500000 Pa·s at 60 DEG C, the surface of the hydrophobic rubber particles is treated by a silane-based hydrophobic agent, and the content of the silane-based hydrophobic agent is 1-3% of the total mass, the particle size of the hydrophobic rubber particles is 1-3mm, and the thickness of the wear-resistant noise-reducing surface layer is 20-30mm.

[0007] The application is further provided that the particle size of the coarse aggregate one is 5-20mm, and the crushing value of the coarse aggregate one is not more than 20%.

[0008] The application is further provided that the buffer layer comprises a plurality of layers of composite geotextile.

[0009] The application is further provided that the surface of the composite geotextile is provided with a raised dot matrix structure, the dot matrix structure is embedded in the bottom of the upper high-toughness water-permeable middle layer to enhance the interlayer shear resistance.

[0010] The application is further provided that the perforated longitudinal drainage blind pipe is pre-embedded in the gravel cushion layer, and the drainage blind pipe is connected with the drainage system of the side edge of the road surface.

[0011] The application is further provided that the reinforcing fibers are compounded by polyester fibers and basalt short fibers at a mass ratio of 1:1 to 1:3.

[0012] The application is further provided that the reinforcing fibers are first mixed with the coarse aggregate two by dry mixing method, and then wet mixed with the rubber material one to ensure the uniform formation of the three-dimensional network structure.

[0013] The application is further provided that the roadbed layer is made of porous concrete, and the pores inside the roadbed layer form a water storage cavity for temporarily storing excess rainwater.

[0014] A construction method of a high-load water-permeable asphalt pavement is used for building a high-load water-permeable asphalt pavement, and comprises the following steps: S1: excavate, level and compact the roadbed to meet the design elevation and compaction requirements, then set up a formwork and pour porous concrete to form a roadbed layer with an internal water storage cavity, and cure to the specified strength; S2: on the accepted roadbed layer, spread the 5-20mm coarse aggregate I, and use a road roller to compact it in layers to the design thickness and density to form a gravel cushion layer, and simultaneously pre-bury the perforated longitudinal drainage blind pipe during the spreading and compacting process, and ensure smooth communication with the drainage system on the side of the road surface; S3: lay the composite geotextile as a buffer layer on the leveled gravel cushion layer, and ensure that the dot matrix structure of the composite geotextile faces upward; S4: make a high-toughness water-permeable middle layer: S4.1: mix polyester fibers and basalt short fibers at a mass ratio of 1:1 to 1:3, and put them into a mixing cylinder together with coarse aggregate II for dry mixing, so that the reinforcing fibers are uniformly dispersed in the coarse aggregate II to preliminarily form a three-dimensional network structure; S4.2: wet mix the mixed reinforcing fibers and coarse aggregate II with glue I to ensure uniform formation of the three-dimensional network structure, and obtain mixed material I; S4.3: transport the mixed material I to the site, spread it on the buffer layer while hot, control the loose thickness to ensure that the thickness after compaction is between 40-60mm, and then use a heavy road roller for compaction until the designed density and flatness are reached; S5: make a wear-resistant and noise-reducing surface layer: S5.1: first, hydrophobize the surface of the hydrophobic rubber particles with a particle size of 1-3mm using a silane-based hydrophobic agent, then pre-mix them with glue II to fully immerse the hydrophobic rubber particles in asphalt, and then mix them with coarse aggregate III to form uniform mixed material II; S5.2: spread the mixed material II on the high-toughness water-permeable middle layer that has been compacted and formed, control the loose thickness to ensure that the thickness after compaction is between 20-30mm, and use a light road roller for fine compaction to avoid overcompaction, so as to simultaneously ensure the density, structural depth and noise reduction function of the surface layer.

[0015] In summary, the present application has the following advantages: I. By using SBS and rubber powder composite modified glue I in the high-toughness water-permeable middle layer, and adding polyester fibers and basalt fibers to form a three-dimensional network structure, the high-toughness water-permeable middle layer has high toughness to withstand heavy loads, and the wear-resistant and noise-reducing surface layer uses high-viscosity glue II and hydrophobic rubber particles to ensure the durability of the wear-resistant and water-permeable functions; Second, the roadbed, which is made of porous concrete, forms a water-retaining cavity inside, which can temporarily store a large amount of rainwater and effectively reduce the peak runoff. The crushed stone cushion layer on it works in conjunction with the pre-embedded perforated longitudinal drainage blind pipes to quickly guide excess rainwater to the side drainage system, which significantly improves the ability to prevent urban flooding. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the external structure of the present invention; Figure 2 This is a schematic diagram of the internal structure of the present invention. Figure One ; Figure 3 This is a schematic diagram of the internal structure of the present invention. Figure Two .

[0017] In the diagram: 1. Road base layer; 2. Crushed stone subbase; 3. High-toughness permeable water layer; 4. Wear-resistant and noise-reducing surface layer; 5. Buffer layer; 6. Drainage blind pipe. Detailed Implementation

[0018] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of this application can be combined with each other.

[0019] In the description of this invention, it should be noted that the terms "upper", "lower", "inner", "outer", "top / bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0020] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," "sleeved / connected," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0021] A high-load-bearing permeable asphalt pavement, such as Figures 1-3As shown, it includes a road base layer 1 and a crushed stone subbase layer 2. The road base layer 1 is laid flat at the bottom of the road surface. The road base layer 1 is made of porous concrete. Its internal pores form a water storage cavity for temporarily storing excess rainwater. As the load-bearing structure of the asphalt pavement, the porous structure on the road base layer 1 can bear the effects of water storage and drainage. The porous concrete forms a water storage cavity with high porosity and interconnected internal structure by precisely controlling the aggregate particle size, cement dosage and additives. Specifically, porous concrete uses single-graded coarse aggregate (such as basalt or limestone) with a particle size of 10-20mm, a cement content of 250-350 kg / m³, a water-cement ratio of 0.28-0.35, and adds 0.5%-1.5% polycarboxylate superplasticizer and 0.1%-0.3% rosin thermal polymer air-entraining agent by mass of cement to form a connected pore structure with a porosity of 15%-25%. When rainfall occurs, rainwater infiltrating from top to bottom will quickly pass through the upper structural layers and eventually flow into the road base layer 1. This solves the risk of waterlogging that may be caused by excessive short-term runoff and insufficient underground infiltration rate during heavy rainfall. Rainwater is temporarily stored in this water-storing cavity, which greatly reduces the pressure on the urban drainage network during peak periods. At the same time, porous concrete itself has high compressive and flexural strength, which can evenly distribute the vehicle load above to the subgrade, ensuring the long-term stability and safety of the entire road structure under heavy traffic.

[0022] In one embodiment, the crushed stone subbase 2 is laid above the road base layer 1, and perforated longitudinal drainage blind pipes 6 are pre-embedded within the crushed stone subbase 2. The drainage blind pipes 6 are connected to the drainage system on the side of the road surface. The crushed stone subbase 2 is made of high-quality coarse aggregate with a particle size of 5-20mm and a crushing value of no more than 20%, and is laid by layered compaction to form a high-strength and stable skeleton structure. It receives and drains rainwater that overflows from the water storage cavity of the road base layer 1 or has not yet infiltrated. During the paving and compaction of the crushed stone subbase 2, the perforated longitudinal drainage blind pipes 6 are pre-embedded simultaneously. These drainage blind pipes 6 are made of PVC or HDPE material, with a diameter of 100-200mm and a perforation rate of not less than 5%. Their laying slope is not less than 0.3%, and they are smoothly connected to the roadside drainage system (such as storm drains or drainage ditches) through pipe joints or direct embedding. The numerous holes surrounding these drainage blind pipes 6 can quickly collect free water flowing in the crushed stone subbase 2. The collected water can flow smoothly to the main drainage system by gravity. Working in conjunction with the active water storage function of the subgrade 1, it ensures that even under extreme rainfall conditions, there is no water accumulation within the entire pavement structure, fundamentally guaranteeing the stability of the subgrade soil and maintaining the long-lasting and reliable drainage performance of the permeable pavement.

[0023] In one embodiment, the load-bearing water-storage composite layer is disposed above the crushed stone cushion layer 2. The load-bearing water-storage composite layer includes a high-toughness permeable middle layer 3 and a wear-resistant and noise-reducing surface layer 4. The high-toughness permeable middle layer 3 is disposed below the wear-resistant and noise-reducing surface layer 4.

[0024] Among them, the high-toughness permeable middle layer 3 is made of rubber compound one, reinforcing fiber and coarse aggregate two. Rubber compound one is made of high-elasticity asphalt modified by adding SBS modifier and rubber powder. The rubber powder is made by grinding waste tire rubber. The amount of SBS modifier is 4%-6% of the asphalt mass, and the amount of rubber powder is 15%-20% of the asphalt mass. The rubber powder is made by grinding waste tire rubber with a particle size of 30-80 mesh. Through composite modification, the penetration (25℃) of high-elasticity asphalt is 40-60dmm, the softening point is not lower than 70℃, and the ductility (5℃) is not less than 30 cm, thus possessing high elasticity and fatigue resistance characteristics. SBS modifier endows highly elastic asphalt with excellent high and low temperature performance and elastic recovery ability, while rubber powder from waste tires further significantly improves the toughness, viscosity and fatigue resistance of asphalt, realizing the resource utilization of waste. Coarse aggregate II uses hard, wear-resistant basalt or diabase with a particle size range of 5-15mm, of which 5-10mm particles account for 40%-60% and 10-15mm particles account for 40%-60%. However, the improvement of asphalt binder alone is not enough to withstand repeated heavy load impacts, so reinforcing fibers are added. The dosage of reinforcing fibers is 0.2%-0.4% of coarse aggregate II to achieve a balance between performance and cost. If the dosage is less than 0.2%, the reinforcing fibers cannot form an effective spatial network, and the reinforcing effect is limited. If it is higher than 0.4%, the reinforcing fibers are prone to agglomeration, which will destroy the uniformity of mixture I.

[0025] In one embodiment, the reinforcing fiber is made of polyester fiber or basalt short fiber, or a combination of both. Specifically, the reinforcing fiber is made of polyester fiber and basalt short fiber in a mass ratio of 1:1 to 1:3. The reinforcing fiber forms a three-dimensional network structure in the first mixture. The flexible polyester fiber can adsorb a large amount of high-elasticity asphalt, increasing the thickness of the high-elasticity asphalt film from the conventional 10μm level to more than 20μm level. This greatly improves the coating of the high-elasticity asphalt on the second coarse aggregate, fundamentally enhancing the water damage resistance and durability of the first mixture. Meanwhile, the high-modulus basalt short fiber can effectively bridge the micro-cracks in the first mixture, disperse and absorb the stress generated by the load, and improve the tensile strength and impact toughness of the first mixture.

[0026] First, the compounded reinforcing fibers are mixed with coarse aggregate two in a dry state. This process utilizes the intense collisions and friction between the coarse aggregate two to thoroughly disperse the reinforcing fibers, allowing them to evenly intersperse and fix within the gaps of the coarse aggregate two, thus pre-building a skeletal network. If the traditional method of adding the reinforcing fibers simultaneously with wet asphalt is used, the reinforcing fibers are easily clumped together by the highly elastic asphalt, making even dispersion impossible. During subsequent wet mixing with binder one, the highly elastic modified asphalt fully impregnates this pre-formed composite skeleton, binding each fiber together to form a unified three-dimensional fiber network. The tensile and shear strength of the first mixture is improved, reducing its rutting deformation under heavy loads. This effectively inhibits the propagation of microcracks caused by load and temperature changes, extending fatigue life. Furthermore, it enhances the bonding force between the second coarse aggregate, enabling the first mixture to maintain extremely high anti-scattering ability even when saturated with water. The thickness of the high-toughness permeable sublayer is 40-60mm. This thickness provides the high-toughness permeable sublayer 3 with excellent structural elasticity and damage tolerance, ensuring the service life of the high-toughness permeable sublayer.

[0027] The wear-resistant and noise-reducing surface layer 4, serving as the direct bearing layer for vehicle loads and environmental forces, utilizes high-viscosity modified asphalt with a dynamic viscosity of no less than 500,000 Pa·s at 60℃ as the second binder. This gives the second binder strong cohesiveness and adsorption, enabling it to form a thick and tough asphalt film that firmly bonds the third coarse aggregate and functional additives into a unified whole. This viscosity directly translates into the high-temperature stability of the second mixture, effectively resisting the repeated rubbing and shearing of heavy-duty vehicle tires, inhibiting oil bleeding and permanent deformation, and ensuring its wear resistance. The third coarse aggregate is made of basalt or diabase, with a particle size range of 3-5mm and uniform gradation. The amount of the third coarse aggregate accounts for 80%-85% of the total mass of the second mixture, and rubber particles surface-treated with silane hydrophobic agents are added to it. The dosage is precisely controlled between 1% and 3% of the total mass. The hydrophobic treatment process involves: applying silane hydrophobic agents... A hydrophobic agent (such as octyltriethoxysilane) is diluted in ethanol at a ratio of 0.5%-1% and then sprayed onto the surface of rubber granules. After drying at 60-80℃ for 30 minutes, a hydrophobic film is formed on the surface of the rubber granules, transforming the originally hydrophilic rubber granules into a hydrophobic state. This weakens the adhesion of water molecules in the pores of the mixture, allowing intruding rainwater to be quickly discharged under gravity. This not only improves the immediate permeability but also significantly reduces the risk of long-term pore blockage caused by the adhesion and retention of dust and impurities through this self-cleaning effect, ensuring the durability of the permeability function. Furthermore, the hydrophobic rubber granules and high-viscosity modified asphalt work synergistically to construct an interface with extremely strong water damage resistance, improving the surface's anti-stripping performance.

[0028] The hydrophobic rubber particles are controlled within a size range of 1-3 mm. This size range is crucial for achieving a balance between noise reduction and structural integrity. These highly elastic microparticles are uniformly dispersed within the hard coarse aggregate 3. When a tire rolls over the road surface, these elastic units effectively absorb and buffer the vibration energy generated by the impact between the tire and the road surface. Simultaneously, by changing the air resonance frequency within the pores, they significantly reduce tire and road noise at the source. This particle size ensures that the rubber particles can fully fill some of the voids between the coarse aggregate 3 without completely blocking necessary connecting pores. Thus, while ensuring noise reduction, the effective porosity of the wear-resistant and noise-reducing surface layer 4 is maintained to meet the requirements of rapid drainage. The 20-30 mm thickness of the wear-resistant and noise-reducing surface layer 4 is sufficient to accommodate a adequate number of hydrophobic rubber particles and coarse aggregate 3. It ensures that the surface structure has sufficient mass to resist wear, preventing the functional layer from failing prematurely due to insufficient thickness during long-term use. At the same time, it avoids unnecessary material waste and cost increases caused by over-paving, ensuring the economic rationality of the entire road structure.

[0029] A buffer layer 5 is positioned between the crushed stone cushion layer 2 and the high-toughness permeable sub-layer 3. The buffer layer 5 comprises several layers of composite geotextile. This composite geotextile not only possesses excellent permeability and filtration capabilities, allowing rainwater to smoothly penetrate from top to bottom into the underlying crushed stone cushion layer 2, but also effectively prevents fine particles from the roadbed 1 from migrating upwards under dynamic water pressure, thus blocking the pores of the upper permeable asphalt mixture and ensuring the long-term unobstructed flow of the entire drainage path. Under heavy traffic loads, a stiffness difference arises between the lower semi-rigid crushed stone cushion layer 2 and the upper high-toughness permeable sub-layer 3, easily leading to stress concentration at the interlayer interface, which can cause shear slip or even overall structural failure. The composite geotextile, with its good toughness and elongation, can absorb and dissipate this concentrated stress, distributing vertical loads and horizontal shear forces more evenly, thereby protecting the relatively fragile structural interface and greatly improving the long-term service performance of the pavement under heavy loads, frequent braking, and frequent starting conditions.

[0030] The composite geotextile surface features a raised lattice structure embedded in the bottom of the upper high-toughness permeable sub-layer 3 to enhance interlayer shear resistance. The lattice structure consists of hemispherical or pyramidal protrusions, 2-5 mm high, with a density of 100-200 per square meter. After laying, these raised lattice structures partially embed themselves into the bottom of the upper, not yet fully cooled and hardened, high-toughness permeable sub-layer 3 during compaction. The temperature of the high-toughness permeable sub-layer 3 mixture after paving is no lower than 140℃, at which point the asphalt mixture possesses sufficient plasticity to allow the lattice structure to embed without damage. The raised structures embedded in the bottom of the high-toughness permeable sub-layer 3 form mechanical anchoring points at the interface. When horizontal shear forces attempt to cause relative displacement between the two layers, these embedded protrusions directly bear the shear force, resisting slippage through their own shear strength and strong bond with the surrounding mixture. It not only solves the problems of interlayer drainage and stress buffering, but also fundamentally improves the interlayer shear resistance, ensuring that the multi-layer permeable pavement structure can work together as a whole throughout its entire life cycle, effectively avoiding common defects such as interlayer peeling and shoving, and achieving the goal of high load-bearing capacity.

[0031] A construction method for high-load-bearing permeable asphalt pavement, used to construct a high-load-bearing permeable asphalt pavement, includes the following steps: S1: Excavate, level and compact the roadbed to meet the design elevation and compaction requirements. Then, set up formwork and pour porous concrete to form the roadbed 1 with water-retaining cavities inside, and cure it to the specified strength.

[0032] The mix proportions for porous concrete are as follows: coarse aggregate (10-20mm particle size) 1500-1600 kg / m³, cement 300-350 kg / m³, water-cement ratio 0.30-0.35, water-reducing agent (polycarboxylate-based) 1%-1.5% of cement mass, and air-entraining agent (rosin thermal polymer) 0.1%-0.2% of cement mass. After pouring, cover and cure for at least 7 days to reach the design strength (compressive strength not less than 20MPa).

[0033] The process of constructing a porous concrete road base layer 1 by setting up formwork is not only a structural load-bearing layer, but also a functional water storage carrier. The construction quality control is directly related to the water storage capacity and long-term stability of the entire asphalt pavement. It is necessary to ensure that a uniform and interconnected water storage cavity is formed inside and that it reaches the specified strength after curing to support all the structural layers above and traffic loads.

[0034] S2: On the qualified road base 1, coarse aggregate with a particle size of 5-20mm is laid and compacted in layers to the designed thickness and density using a road roller to form crushed stone cushion layer 2. During the paving and compaction process, perforated longitudinal drainage blind pipes 6 are pre-embedded simultaneously, and it is ensured that they are smoothly connected to the drainage system on the side of the road.

[0035] Coarse aggregate with a particle size of 5-20mm is spread and compacted in layers on the road base layer 1 to form a crushed stone cushion layer 2, achieving a high-density and stable skeleton structure. Simultaneously, perforated longitudinal drainage blind pipes 6 are pre-embedded. During the compaction process, the position and slope of the drainage blind pipes 6 are fixed to ensure smooth connection with the drainage system on the side of the road, providing a solid subbase for coping with heavy rainfall.

[0036] S3: Lay composite geotextile as buffer layer 5 on the flat crushed stone cushion layer 2, ensuring that the lattice structure surface of the composite geotextile faces upward.

[0037] S4: Constructing a high-toughness, permeable middle layer 3: S4.1: Polyester fiber and basalt short fiber are compounded in a mass ratio of 1:1 to 1:3 and added together with coarse aggregate 2 into a mixing tank for dry mixing, so that the reinforcing fiber is evenly dispersed in coarse aggregate 2 and a three-dimensional network structure is initially formed. S4.2: The mixed reinforcing fibers and coarse aggregate II are wet-mixed with rubber compound I to ensure the uniform formation of its three-dimensional network structure, resulting in mixture I. The proportion of mixture I by mass is: 100 parts coarse aggregate II, 4.5-5.5 parts rubber compound I, and 0.2-0.4 parts reinforcing fibers (based on the mass of coarse aggregate II). S4.3: Transport the mixed material to the site and spread it on the buffer layer 5 while it is still hot. Control the loose thickness to ensure that the thickness after compaction is between 40-60mm. Then use a heavy roller to compact it until the designed density and smoothness are achieved.

[0038] The construction of the high-toughness permeable intermediate layer 3 is crucial to ensuring the overall structural load-bearing capacity. Its core lies in using a dry-mixing method to treat the reinforcing fibers. First, polyester fibers and basalt short fibers are compounded at a specific mass ratio, then added to a mixing tank with coarse aggregate 2 for dry mixing. This step utilizes the collision and friction of the coarse aggregate 2 to thoroughly disperse the trace amounts of reinforcing fibers, initially embedding them into the gaps between the coarse aggregate 2, laying the foundation for the subsequent formation of a three-dimensional network reinforcement structure penetrating the binder 1. Subsequently, high-elasticity asphalt is added for wet mixing, ultimately resulting in a mixture 1 that combines high toughness and large porosity. During paving and compaction, the high-temperature mixture 1, under pressure, tightly integrates with the lattice structure of the buffer layer 5, forming a strong mechanical anchor and significantly enhancing the interlayer shear resistance.

[0039] S5: Fabrication of a wear-resistant and noise-reducing surface layer 4: S5.1: First, treat the surface of hydrophobic rubber particles with a particle size of 1-3mm with a silane-based hydrophobic agent for hydrophobicity, and then premix them with rubber compound two. The premixing is carried out by mechanically mixing at 160-170℃ for 30-60 seconds to ensure that the hydrophobic rubber particles are fully wetted by asphalt. Then, mix them together with coarse aggregate three to form a uniform mixture two. The proportion of mixture two by mass is: 100 parts of coarse aggregate three, 5.0-6.0 parts of rubber compound two, and 1-3 parts of hydrophobic rubber particles. S5.2: On the compacted high-toughness permeable water layer 3, spread the mixture 2, control the loose thickness, and ensure that the thickness after compaction is between 20-30mm. Use a light roller for fine rolling to avoid over-compaction, so as to ensure the surface density, texture depth and noise reduction function at the same time.

[0040] The construction of the wear-resistant and noise-reducing surface layer 4 emphasizes functionality. Its pretreatment involves surface treatment of the rubber particles with a silane-based hydrophobic agent before pre-mixing them with rubber compound 2. This process ensures that the hydrophobic rubber particles are fully impregnated and coated with high-viscosity asphalt, thus enabling them to persistently exert their hydrophobic, noise-reducing, and toughening effects in the final mixture 2 formed with coarse aggregate 3. After paving, a light roller is used for fine compaction, ensuring initial density while avoiding over-compaction to protect the surface coarse aggregate texture and the microscopic effects of the elastic rubber particles. The final result is a unified road surface with high wear resistance, deep noise reduction, and efficient drainage.

[0041] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A high-load-bearing permeable asphalt pavement, characterized in that, include: The road base course and the crushed stone subbase course are provided. The road base course is laid flat at the bottom of the road surface, and the crushed stone subbase course is set on top of the road base course. The crushed stone subbase course is made of several coarse aggregates laid together. A load-bearing water-storage composite layer is disposed above a crushed stone cushion layer. The load-bearing water-storage composite layer includes a high-toughness permeable middle layer and a wear-resistant and noise-reducing surface layer. The high-toughness permeable middle layer is disposed below the wear-resistant and noise-reducing surface layer. A buffer layer is placed between the crushed stone cushion layer and the high-toughness permeable water layer; The high-toughness permeable sub-layer is made of rubber compound one, reinforcing fibers and coarse aggregate two. Rubber compound one is made of high-elasticity asphalt modified with SBS modifier and rubber powder. The rubber powder is made from waste tire rubber. The reinforcing fibers are made of polyester fibers or basalt short fibers and a combination of the two. The reinforcing fibers are uniformly dispersed in rubber compound one. The amount of reinforcing fibers is 0.2%-0.4% of coarse aggregate two. The reinforcing fibers form a three-dimensional network structure in rubber compound one. The thickness of the high-toughness permeable sub-layer is 40-60mm. The wear-resistant and noise-reducing surface layer comprises rubber compound II, hydrophobic rubber particles, and coarse aggregate III. Rubber compound II is high-viscosity modified asphalt with a dynamic viscosity of not less than 500,000 Pa·s at 60°C. The surface of the hydrophobic rubber particles is treated with a silane-based hydrophobic agent, with the amount accounting for 1%-3% of the total mass. The particle size of the hydrophobic rubber particles is 1-3 mm. The thickness of the wear-resistant and noise-reducing surface layer is 20-30 mm.

2. The high-load-bearing permeable asphalt pavement according to claim 1, characterized in that: The coarse aggregate has a particle size of 5-20mm, and the crushing value of the coarse aggregate is not greater than 20%.

3. The high load-bearing permeable asphalt pavement according to claim 1, characterized in that: The buffer layer comprises several layers of composite geotextile.

4. The high load-bearing permeable asphalt pavement according to claim 3, characterized in that: The surface of the composite geotextile is provided with a raised dot matrix structure, which is embedded in the bottom of the high-toughness permeable water layer above to enhance the interlayer shear resistance.

5. A high-load-bearing permeable asphalt pavement according to claim 1, characterized in that: The crushed stone subbase is pre-embedded with a perforated longitudinal drainage blind pipe, which is connected to the drainage system on the side of the road.

6. The high load-bearing permeable asphalt pavement according to claim 1, characterized in that: The reinforcing fiber is composed of polyester fiber and basalt short fiber in a mass ratio of 1:1 to 1:

3.

7. A high-load-bearing permeable asphalt pavement according to claim 6, characterized in that: The reinforcing fibers are first mixed with coarse aggregate two by dry mixing, and then wet mixed with adhesive one to ensure the uniform formation of its three-dimensional network structure.

8. A high-load-bearing permeable asphalt pavement according to claim 1, characterized in that: The roadbed is made of porous concrete, and its internal pores form a water storage cavity for temporarily storing excess rainwater.

9. A construction method for a high-load-bearing permeable asphalt pavement, used to construct a high-load-bearing permeable asphalt pavement as described in any one of claims 1-8, characterized in that, Includes the following steps: S1: Excavate, level and compact the roadbed to meet the design elevation and compaction requirements. Then, set up formwork and pour porous concrete to form a roadbed with water-retaining cavities inside, and cure it to the specified strength. S2: On the qualified road base, pave coarse aggregate with a particle size of 5-20mm, and use a road roller to compact it in layers to the design thickness and density to form a crushed stone cushion layer. During the paving and compaction process, perforated longitudinal drainage blind pipes are pre-embedded simultaneously, and it is ensured that they are smoothly connected to the drainage system on the side of the road. S3: Lay composite geotextile as a buffer layer on a flat crushed stone cushion layer, ensuring that the lattice structure surface of the composite geotextile faces upward. S4: Constructing a high-toughness, permeable middle layer: S4.1: Polyester fiber and basalt short fiber are compounded in a mass ratio of 1:1 to 1:3 and added together with coarse aggregate 2 into a mixing tank for dry mixing, so that the reinforcing fiber is evenly dispersed in coarse aggregate 2 and a three-dimensional network structure is initially formed. S4.2: The mixed reinforcing fibers and coarse aggregate II are wet-mixed with rubber compound I to ensure the uniform formation of its three-dimensional network structure, thus obtaining mixture I; S4.3: Once the mixed material is transported to the site, it is spread on the buffer layer while it is still hot. The loose thickness is controlled to ensure that the thickness after compaction is between 40-60mm. Then, a heavy roller is used to compact it until the designed density and smoothness are achieved. S5: Create a wear-resistant and noise-reducing surface layer: S5.1: First, the surface of hydrophobic rubber particles with a particle size of 1-3mm is treated with a silane-based hydrophobic agent, and then premixed with rubber compound two to ensure that the hydrophobic rubber particles are fully impregnated with asphalt. Then, it is mixed with coarse aggregate three to form a uniform mixture two. S5.2: On the compacted high-toughness permeable subgrade, spread the second mixture, control the loose thickness, and ensure that the thickness after compaction is between 20-30mm. Use a light roller for fine compaction to avoid over-compaction, so as to ensure the surface density, texture depth and noise reduction function at the same time.

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