An asphalt pavement structure with both drainage and anti-rutting and temperature crack alleviating functions

Abstract

The utility model discloses a kind of asphalt pavement structure with drainage anti-rutting and temperature crack mitigation function, which is sequentially provided with functional integrated surface layer, low-temperature anti-cracking flexible stress absorbing layer, high-modulus load-bearing layer, base layer and bottom base layer from top to bottom on roadbed;The functional integrated surface layer uses high anti-rutting modified permeable asphalt mixture to realize drainage and anti-rutting;The low-temperature anti-cracking flexible stress absorbing layer uses high-elastic modified asphalt macadam mixture to absorb temperature tensile stress to suppress cracks;The high-modulus load-bearing layer uses high-modulus asphalt concrete to bear load and resist permanent deformation.This structure breaks through traditional design contradictions through "functional layering, cooperative work", prolongs pavement life, has significant full life cycle cost advantage, and is suitable for highway construction under complex service environment.

Description

Technical Field

[0001] This utility model relates to the field of asphalt pavement structure technology, specifically to an asphalt pavement structure that combines drainage and rutting resistance with temperature crack mitigation functions. Background Technology

[0002] Asphalt pavements are widely used in highway transportation due to their comfortable driving experience, convenient construction, and low maintenance costs. However, in complex service environments, existing asphalt pavements often face multiple related technical problems, seriously affecting their service life and driving safety, as follows:

[0003] The contradiction between the singular function of pavement and the complex nature of its failure modes: Traditional pavement design often addresses a single problem, such as using dense-graded asphalt concrete (AC) or high-modulus asphalt concrete (HMAC) to resist rutting, or using open-graded drainage layers (OGFC) to improve drainage. However, actual pavement damage is caused by the synergy of multiple factors. Fatigue cracking (especially top-down cracking) can create water penetration channels, accelerate material deterioration and cause water damage, and also reduce pavement load-bearing capacity and exacerbate rutting. Existing structures lack comprehensive defense capabilities against the coupled failure chain of "rutting-cracks-water damage".

[0004] The inherent conflict in material performance requirements: Asphalt materials are highly temperature sensitive, creating a natural contradiction in pavement performance requirements. Summer rutting resistance requires high stiffness and stability of the mixture, while winter low-temperature cracking prevention requires low-temperature flexibility; moreover, high porosity (to achieve excellent drainage) weakens the mixture skeleton and reduces rutting resistance. Existing technologies struggle to reconcile these conflicts in a single pavement structure.

[0005] Interlayer stress transfer and cumulative damage: Under traffic loads and environmental influences, stress concentrates between layers, and cracking is easily triggered when temperature stress exceeds the tensile strength of the asphalt layer. These cracks (load fatigue cracks, temperature cracks) can propagate downwards from the surface layer or reflect upwards from the base layer, eventually penetrating the entire asphalt layer and compromising the integrity of the pavement structure. Existing structures lack efficient stress absorption interruption mechanisms and cannot alleviate interlayer stress transfer (especially concentrated tensile stress caused by sudden temperature drops), leading to crack propagation and cumulative damage.

[0006] Therefore, there is an urgent need for an asphalt pavement structure that combines drainage and rutting resistance with temperature crack mitigation. Utility Model Content

[0007] In view of the shortcomings of the existing technology, this utility model provides an asphalt pavement structure that combines drainage and rutting resistance with temperature crack mitigation.

[0008] This utility model discloses an asphalt pavement structure that combines drainage, rutting resistance and temperature crack mitigation functions, comprising, from top to bottom, a functional integrated surface layer, a low-temperature crack-resistant flexible stress-absorbing layer, a high-modulus load-bearing layer, a base layer and a subbase layer;

[0009] The functional integrated surface layer is a high-rutting-resistant modified permeable asphalt mixture layer, which is used to achieve rapid drainage of rainwater from the road surface and resistance to high-temperature rutting.

[0010] The low-temperature crack-resistant flexible stress-absorbing layer is a high-elasticity modified asphalt-aggregate mixture layer, which is used to absorb and dissipate the temperature tensile stress under low-temperature conditions to inhibit crack initiation and propagation.

[0011] The high-modulus load-bearing layer is a high-modulus asphalt concrete layer, which is used to bear traffic loads and provide structural stiffness and resistance to permanent deformation.

[0012] As a further improvement of this utility model, the thickness of the high rutting resistance modified permeable asphalt mixture layer is 4-6 cm; the thickness of the high elasticity modified asphalt macadam mixture layer is 2-3 cm; and the thickness of the high modulus asphalt concrete layer is 6-8 cm.

[0013] The thickness of the base layer is 6-8 cm, and the thickness of the subbase layer is 6-8 cm.

[0014] As a further improvement of this utility model, the high rutting resistance modified permeable asphalt mixture layer includes a skeleton void structure and composite modified asphalt filled in the skeleton void structure.

[0015] The gradation type of the skeleton void structure is PAC-13 or PAC-16, and the porosity of the skeleton void structure is 18%-22%; the composite modified asphalt includes SBS modified asphalt and anti-rutting agent.

[0016] As a further improvement of this utility model, the high-elasticity modified asphalt macadam mixture layer is an open-graded fine-grained high-elasticity modified asphalt macadam mixture layer or a semi-open-graded fine-grained high-elasticity modified asphalt macadam mixture layer.

[0017] As a further improvement of this utility model, the high-elasticity modified asphalt aggregate mixture layer includes 6% to 8% modified asphalt, and the modified asphalt includes SBR modified asphalt or low-grade asphalt.

[0018] As a further improvement of this utility model, the resilient modulus of the high modulus asphalt concrete layer is ≥14000MPa.

[0019] As a further improvement of this utility model, the high modulus asphalt concrete layer includes a skeleton-dense aggregate and a high modulus asphalt binder.

[0020] The gradation type of the dense aggregate is AC-20 or AC-25; the high modulus asphalt binder is AH-50 or AH-30 heavy traffic road petroleum asphalt.

[0021] As a further improvement of this utility model, both the base layer and the subbase layer are cement-stabilized crushed stone layers, lime-fly ash-stabilized crushed stone layers, or graded crushed stone layers.

[0022] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0023] Compared to simple drainage pavements, this utility model adds a dedicated low-temperature crack-resistant flexible stress-absorbing layer and a high-modulus load-bearing layer to the asphalt pavement structure, effectively solving the common problems of insufficient structural strength and susceptibility to low-temperature cracking in drainage pavements. Compared to traditional rutting-resistant pavements, this structure achieves drainage through a top functional integrated surface layer and crack resistance through a middle stress-absorbing layer, solving the defects of poor drainage and low-temperature flexibility in traditional rutting-resistant pavements. This structure, through a novel integrated design formed by the complementary functions of each layer, can simultaneously address the three core requirements of drainage, rutting resistance, and resistance to temperature cracking.

[0024] This invention breaks through the traditional design limitations of "high porosity inevitably leads to low stability" and "high-temperature stability and low-temperature flexibility are mutually exclusive." It abandons the idea of ​​"a single material achieving multiple properties" and adopts a system design of "functional layering and collaborative operation": the top functional integrated layer achieves the dual functions of "drainage + rutting resistance" based on material properties; the middle stress-absorbing layer is dedicated to ensuring low-temperature flexibility to suppress temperature cracking; and the lower high-modulus load-bearing layer is dedicated to providing high-temperature stiffness to bear the load. Each layer forms a synergistic relationship of mutual protection and promotion. The flexible layer prevents the high-modulus layer from being impacted by temperature stress, the drainage layer protects the lower structure from water damage, and the high-modulus layer provides stable support for the upper functional layers, ultimately producing a non-linear gain effect of "1+1+1>3," significantly improving the overall lifespan and reliability of the pavement. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of an asphalt pavement structure that combines drainage, rutting resistance, and temperature crack mitigation functions, as disclosed in one embodiment of the present invention.

[0026] In the picture:

[0027] 1. Functional integrated surface layer; 2. Low-temperature crack-resistant flexible stress-absorbing layer; 3. High-modulus load-bearing layer; 4. Base layer; 5. Subbase layer; 6. Subgrade. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0029] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model 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, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0030] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0031] The present invention will now be described in further detail with reference to the accompanying drawings:

[0032] like Figure 1 As shown, the asphalt pavement structure according to this utility model, which combines drainage, rutting resistance, and temperature crack mitigation functions, includes, from top to bottom, a functional integrated surface layer 1, a low-temperature crack-resistant flexible stress-absorbing layer 2, a high-modulus load-bearing layer 3, a base layer 4, a subbase layer 5, and a roadbed 6. The functional integrated surface layer 1 is a high-rutting-resistant modified permeable asphalt mixture layer, used to achieve rapid drainage of rainwater and resistance to high-temperature rutting. The low-temperature crack-resistant flexible stress-absorbing layer 2 is a high-elasticity modified asphalt-aggregate mixture layer, used to absorb and dissipate temperature tensile stress under low-temperature conditions to inhibit crack initiation and propagation. The high-modulus load-bearing layer 3 is a high-modulus asphalt concrete layer, used to bear traffic loads and provide structural stiffness and resistance to permanent deformation.

[0033] Specifically:

[0034] like Figure 1As shown in the above embodiments, preferably, the high-rutting-resistant modified permeable asphalt mixture layer serves as the outermost layer of the road surface, directly contacting traffic loads and the natural environment. Its core function is to quickly drain surface rainwater and resist wheel tracks and rutting at high temperatures. It includes a skeleton void structure and composite modified asphalt filling the skeleton void structure. The gradation type of the skeleton void structure is PAC-13 or PAC-16, and the porosity of the skeleton void structure is 18%-22%, which can ensure excellent permeability. The composite modified asphalt includes a high-viscosity modifier or SBS modified asphalt and an anti-rutting agent, which can optimize the interlocking effect of aggregates, so that while maintaining high porosity, the high-temperature dynamic stability of the mixture can reach or even exceed the standard of traditional dense-graded asphalt mixtures (e.g., dynamic stability > 5000 times / mm).

[0035] In the above embodiments, preferably, the thickness of the high rutting resistance modified permeable asphalt mixture layer is 4-6 cm.

[0036] In the above embodiments, preferably, the main function of the high-elasticity modified asphalt macadam mixture layer is as a flexible buffer. On the one hand, it absorbs and dissipates the huge tensile stress caused by a sharp drop in temperature in low-temperature environments, preventing the initiation and propagation of temperature cracks. On the other hand, it plays a role in secondary waterproofing and stress absorption, mitigating the impact of traffic loads on the underlying layer. The high-elasticity modified asphalt macadam mixture layer is an open-graded fine-grained high-elasticity modified asphalt macadam mixture layer or a semi-open-graded fine-grained high-elasticity modified asphalt macadam mixture layer to ensure its deformation capacity. The high-elasticity modified asphalt macadam mixture layer includes 6% to 8% modified asphalt, which includes SBR modified asphalt or low-grade asphalt. In this embodiment, the low-grade asphalt is a low-grade asphalt modified with a high-elasticity polymer, which allows it to maintain excellent tensile properties and flexibility even at low temperatures (such as -20°C).

[0037] In the above embodiments, preferably, the thickness of the high-elasticity modified asphalt macadam mixture layer is 2-3 cm; this thickness is sufficient to form an effective stress-absorbing film, while not causing shear instability due to excessive thickness.

[0038] In the above embodiments, preferably, the high-modulus asphalt concrete layer, as the main load-bearing skeleton of the asphalt structural layer, bears most of the traffic load and provides sufficient stiffness and resistance to permanent deformation for the entire pavement structure. Its resilient modulus is ≥14000MPa, thus possessing excellent rutting resistance. The high-modulus asphalt concrete layer includes a dense aggregate skeleton and a high-modulus asphalt binder; the gradation type of the dense aggregate skeleton is AC-20 or AC-25; the high-modulus asphalt binder is a low-penetration hard asphalt, preferably AH-50 or AH-30 heavy-traffic road petroleum asphalt in this embodiment. Due to the protection of the stress-absorbing layer and drainage layer above, this layer can operate in a relatively stable and dry environment, allowing its rutting resistance to be fully utilized.

[0039] In the above embodiments, preferably, the thickness of the high-modulus asphalt concrete layer is 6-8 cm.

[0040] In the above embodiments, preferably, both the base course 4 and the subbase course 5 are cement-stabilized crushed stone layers, lime-fly ash stabilized crushed stone layers, or graded crushed stone layers. This provides stable and uniform support for the upper asphalt structural layer.

[0041] In the above embodiments, preferably, the thickness of the base layer is 6-8 cm and the thickness of the subbase layer is 6-8 cm.

[0042] Advantages of this utility model:

[0043] Compared to simple drainage pavements, this utility model adds a dedicated low-temperature crack-resistant flexible stress-absorbing layer 2 and a high-modulus load-bearing layer 3 to the asphalt pavement structure, effectively solving the common problems of insufficient structural strength and easy low-temperature cracking in drainage pavements. Compared to traditional rutting-resistant pavements, this structure achieves drainage function through the top functional integrated surface layer 1 and crack resistance function through the middle stress-absorbing layer, solving the defects of poor drainage and poor low-temperature flexibility in traditional rutting-resistant pavements. This structure, through the new integrated design formed by the complementary functions of each layer, can simultaneously meet the three core requirements of drainage, rutting resistance, and temperature crack resistance.

[0044] This invention breaks through the traditional design limitations of "high porosity inevitably leads to low stability" and "high-temperature stability and low-temperature flexibility are mutually exclusive." It abandons the idea of ​​"a single material achieving multiple properties" and adopts a system design of "functional layering and collaborative operation": the top functional integrated surface layer 1 achieves the dual functions of "drainage + rutting resistance" based on material properties; the middle low-temperature crack-resistant flexible stress-absorbing layer 2 is dedicated to ensuring low-temperature flexibility to suppress temperature cracks; and the lower high-modulus load-bearing layer 3 is dedicated to providing high-temperature stiffness to bear the load. Each layer forms a synergistic relationship of mutual protection and promotion. The flexible layer prevents the high-modulus layer from being impacted by temperature stress, the drainage layer protects the lower structure from water damage, and the high-modulus layer provides stable support for the upper functional layers, ultimately producing a non-linear gain effect of "1+1+1>3," significantly improving the overall lifespan and reliability of the pavement.

[0045] This invention significantly extends service life, greatly reduces the number and frequency of subsequent maintenance and overhauls, and minimizes traffic disruption losses caused by maintenance work. From a life-cycle cost (LCCA) perspective, its overall economic benefits are very significant and align with the engineering principles of sustainable development.

[0046] The above are merely preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. An asphalt pavement structure that combines drainage and rutting resistance with temperature crack mitigation functions, characterized in that, It includes, from top to bottom, a functional integrated surface layer, a low-temperature crack-resistant flexible stress-absorbing layer, a high-modulus load-bearing layer, a base layer, and a subbase layer; The functional integrated surface layer is a high-rutting-resistant modified permeable asphalt mixture layer, which is used to achieve rapid drainage of rainwater from the road surface and resistance to high-temperature rutting. The low-temperature crack-resistant flexible stress-absorbing layer is a high-elasticity modified asphalt-aggregate mixture layer, which is used to absorb and dissipate the temperature tensile stress under low-temperature conditions to inhibit crack initiation and propagation. The high-modulus load-bearing layer is a high-modulus asphalt concrete layer, which is used to bear traffic loads and provide structural stiffness and resistance to permanent deformation.

2. The asphalt pavement structure according to claim 1, characterized in that, The thickness of the high rutting resistance modified permeable asphalt mixture layer is 4-6 cm; the thickness of the high elasticity modified asphalt macadam mixture layer is 2-3 cm; and the thickness of the high modulus asphalt concrete layer is 6-8 cm. The thickness of the base layer is 6-8 cm, and the thickness of the subbase layer is 6-8 cm.

3. The asphalt pavement structure according to claim 1, characterized in that, The high rutting resistance modified permeable asphalt mixture layer includes a skeleton void structure and composite modified asphalt filled in the skeleton void structure; The gradation type of the skeleton void structure is PAC-13 or PAC-16, and the porosity of the skeleton void structure is 18%-22%.

4. The asphalt pavement structure according to claim 1, characterized in that, The high-elasticity modified asphalt macadam mixture layer is an open-graded fine-grained high-elasticity modified asphalt macadam mixture layer or a semi-open-graded fine-grained high-elasticity modified asphalt macadam mixture layer.

5. The asphalt pavement structure according to claim 1, characterized in that, The resilient modulus of the high-modulus asphalt concrete layer is ≥14000MPa.

6. The asphalt pavement structure according to claim 1, characterized in that, Both the base course and the subbase course are cement-stabilized crushed stone layers, lime-fly ash-stabilized crushed stone layers, or graded crushed stone layers.

Images