Road structure for preventing arch expansion deformation

Abstract

The utility model relates to the technical field of road structures, in particular to a road structure capable of preventing arch expansion deformation, which comprises a roadbed, an anti-permeation layer, a water-stable base layer and a pavement layer, the anti-permeation layer is paved on the roadbed, the water-stable base layer is paved on the anti-permeation layer, the pavement layer is paved on the water-stable base layer, and the water-stable base layer is paved on the pavement layer. The anti-permeation layer is used for preventing sulfate in the roadbed from permeating into the water-stable base layer. According to the road structure capable of preventing arch expansion deformation provided by the utility model, the impermeable layer is arranged between the roadbed and the water-stable base layer, and the impermeable layer can block the capillary action of sulfate in the salinized soil roadbed, prevent the sulfate in the salinized soil roadbed from permeating into the water-stable base layer and prevent the salt expansion phenomenon of the water-stable base layer; the strength and the stability of the water-stable base layer are protected, the arch expansion phenomenon of the pavement layer is prevented, and the defect that transverse arch expansion cracking of the pavement is prone to occurring in an existing road structure in the salinized soil area is overcome.

Description

Technical Field

[0001] This utility model relates to the field of road structure technology, and in particular to a road structure for preventing arching deformation. Background Technology

[0002] Cement-stabilized base courses, as semi-rigid base courses, have advantages such as high strength, good integrity, durability, and stability, and are therefore widely used in the load-bearing layers of highways in my country.

[0003] However, with the increasing service life of highways, a new type of water-stabilized base course disease has emerged in saline soil areas—lateral bulging cracking. The lateral bulging height typically reaches about 10 cm, and even after the bulging pavement is removed and a new asphalt surface layer is laid, the bulging phenomenon reappears within a certain period. Research indicates that the cause of pavement bulging is not in the surface layer. Excavation and sampling of the bulging areas revealed that the subbase layer did not exhibit bulging, while the water-stabilized base course did. This is particularly prevalent in saline soil areas of my country, where saline soil subgrades are widely distributed due to unique geographical conditions. Sulfates in the saline soil subgrade rise to the water-stabilized base course through capillary action. The sulfates in the water-stabilized base course react with calcium aluminate hydrate (CAH), a hydration product of cement, to form ettringite. The most prominent characteristic of ettringite is its expansibility; the hydration of CaO, Al₂O₃, and CaSO₄ in cement to form ettringite increases the solid phase volume, leading to bulging in the water-stabilized base course.

[0004] Therefore, addressing the occurrence of pavement bulge is of great significance for improving road capacity and comfort. Utility Model Content

[0005] This invention provides a road structure to prevent arching deformation, thereby addressing the defect of existing road structures in saline soil areas that are prone to transverse arching and cracking.

[0006] This utility model provides a road structure for preventing arching deformation, comprising: a roadbed, an anti-permeability layer, a water-stabilized base course, and a pavement layer. The anti-permeability layer is laid on the roadbed, the water-stabilized base course is laid on the anti-permeability layer, and the pavement layer is laid on the water-stabilized base course. The anti-permeability layer is used to prevent sulfates in the roadbed from penetrating into the water-stabilized base course.

[0007] According to the road structure for preventing arching deformation provided by this utility model, the impermeable layer includes a backfill soil layer and a first gravel layer, wherein the backfill soil layer is laid on the roadbed and the first gravel layer is laid on the backfill soil layer.

[0008] According to the road structure for preventing arching deformation provided by this utility model, the porosity of the first gravel layer is 13% to 16%, and the particle size of the gravel in the first gravel layer is 5mm to 40mm.

[0009] According to the road structure for preventing arching deformation provided by this utility model, the thickness of the backfill soil layer is 20cm to 40cm, and the thickness of the first gravel layer is 10cm to 20cm.

[0010] According to the road structure for preventing arching deformation provided by this utility model, the impermeable layer includes a geotextile layer, a sand and soil protective layer, and a second gravel layer. The geotextile layer is laid on the roadbed, the sand and soil protective layer is laid on the geotextile layer, and the second gravel layer is laid on the sand and soil protective layer.

[0011] According to the road structure for preventing arching deformation provided by this utility model, the thickness of the second gravel layer is 15cm to 25cm, and the thickness of the sand and soil protective layer is 10cm to 20cm.

[0012] According to the road structure for preventing arching deformation provided by this utility model, the impermeable layer includes a third gravel layer, a diversion pipe is provided in the third gravel layer at a downward inclination, a blind ditch is provided on the side of the third gravel layer, the outlet end of the diversion pipe is connected to the blind ditch, and the diversion pipe is used to guide the sulfate in the third gravel layer to the blind ditch.

[0013] According to the road structure for preventing arching deformation provided by this utility model, the side of the roadbed is provided with a drainage ditch, and the outlet end of the blind ditch is connected to the drainage ditch.

[0014] According to the road structure for preventing arching deformation provided by this utility model, the thickness of the water-stabilized base course is 30cm to 40cm, and the particle size of the coarse aggregate in the water-stabilized base course is less than or equal to 40mm.

[0015] The road structure for preventing arching deformation provided by this utility model sets an impermeable layer between the subgrade and the water-stabilized base course. The impermeable layer can block the capillary action of sulfates in the saline soil subgrade, prevent sulfates in the saline soil subgrade from penetrating into the water-stabilized base course, prevent the water-stabilized base course from salt swelling, protect the strength and stability of the water-stabilized base course, and prevent the pavement layer from arching. This solves the defect of existing road structures in saline soil areas that are prone to transverse arching and cracking of the pavement.

[0016] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of a road structure for preventing arching deformation provided in one embodiment of the present invention.

[0019] Figure 2 This is a schematic diagram of a road structure for preventing arching deformation provided in the second embodiment of this utility model.

[0020] Figure 3 This is a schematic diagram of a road structure for preventing arching deformation provided in the third embodiment of this utility model.

[0021] Figure label:

[0022] 10. Subgrade; 20. Impermeable layer; 210. Backfill layer; 220. First gravel layer; 230. Geotextile layer; 240. Sand and soil protection layer; 250. Second gravel layer; 260. Third gravel layer; 270. Drainage pipe; 280. Blind drain; 30. Water-stabilized base course; 40. Pavement layer; 50. Alkali drainage ditch. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0024] In the description of the embodiments of this utility model, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of 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. Therefore, they should not be construed as limitations on the embodiments of this utility model. In addition, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0025] In the description of the embodiments of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" 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. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this utility model according to the specific circumstances.

[0026] In this embodiment of the utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0027] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0028] The following is combined Figures 1 to 3 This invention describes the road structure for preventing arching deformation provided by this utility model.

[0029] The following is combined Figures 1 to 3 This invention describes the road structure for preventing arching deformation provided by this utility model.

[0030] See Figures 1 to 3 As shown, the road structure for preventing arching deformation provided in this embodiment of the present invention includes: a roadbed 10, an anti-permeability layer 20, a water-stabilized base course 30, and a pavement layer 40. The anti-permeability layer 20 is laid on the roadbed 10, the water-stabilized base course 30 is laid on the anti-permeability layer 20, and the pavement layer 40 is laid on the water-stabilized base course 30. The anti-permeability layer 20 is used to prevent sulfates in the roadbed 10 from penetrating into the water-stabilized base course 30.

[0031] The road structure for preventing arching deformation provided by this utility model provides an anti-permeability layer 20 between the subgrade 10 and the water-stabilized base course 30. The anti-permeability layer 20 can block the capillary action of sulfates in the saline soil subgrade 10, prevent sulfates in the saline soil subgrade 10 from penetrating into the water-stabilized base course 30, prevent the water-stabilized base course 30 from experiencing salt swelling, protect the strength and stability of the water-stabilized base course 30, and prevent the pavement layer 40 from experiencing arching. This solves the defect of existing road structures in saline soil areas that are prone to transverse arching and cracking of the pavement.

[0032] Specifically, the road structure for preventing arching deformation provided in this embodiment of the present invention can be laid in the following manner.

[0033] Subgrade treatment: First, ensure that the subgrade soil layer 10 meets the design requirements, and carry out necessary compaction and leveling. If subgrade 10 is saline soil or soil that is prone to expansion, reinforcement treatment is required to ensure its stability.

[0034] Impermeable layer laying: Impermeable layer 20 is laid on the treated subgrade 10. The function of impermeable layer 20 is to isolate sulfates in subgrade 10 from contact with water-stabilized base course 30, and to prevent sulfates from penetrating into water-stabilized layer through capillary action.

[0035] It should be noted that the impermeable layer 20 can be laid in a single application or in multiple layers. A single application refers to laying the entire subgrade 10 surface in one go during construction. This is typically suitable for situations with good construction conditions and a relatively flat subgrade 10 soil layer. Multiple layers refer to laying the impermeable layer 20 in several stages, one layer at a time, followed by compaction or fixing until the designed thickness is achieved. Each layer is usually laid after the previous layer has cured or stabilized. This is suitable for complex terrain and uneven subgrade 10 construction environments, allowing for adjustments and refinements layer by layer to ensure the quality and effectiveness of each layer. For thicker impermeable layers 20, layered laying ensures the density of each layer.

[0036] Water-stabilized base course laying: A water-stabilized base course 30 (cement-stabilized crushed stone layer, graded crushed stone layer, or other water-stabilized materials as required by design) is laid on the impermeable layer 20. The water-stabilized base course 30 has high compressive strength and stability, can effectively withstand traffic loads, and has good drainage performance. When laying the water-stabilized base course 30, it should be evenly spread and compacted according to the design thickness to ensure its stability and strength.

[0037] Road surface layer paving: Road surface layer 40 is laid on the water-stabilized base course 30. The road surface layer 40 can be made of different materials, such as asphalt concrete or cement concrete, depending on the road design requirements. Asphalt pavement layers are typically laid using pavers and compacted with appropriate compaction equipment; if it is cement concrete pavement, it requires pouring, smoothing, and curing.

[0038] Post-construction inspection: After all layers have been laid, an on-site inspection is conducted to ensure that the thickness, flatness, and density of each layer meet the design requirements. Simultaneously, the road surface is cured to ensure the material fully hardens and achieves the expected performance.

[0039] See Figure 1 As shown, according to some embodiments of the present invention, the impermeable layer 20 includes a backfill soil layer 210 and a first gravel layer 220. The backfill soil layer 210 is laid on the roadbed 10, and the first gravel layer 220 is laid on the backfill soil layer 210.

[0040] By setting the impermeable layer 20 as a backfill soil layer 210 and a first gravel layer 220, the backfill soil layer 210 is non-saline soil, which can directly contact the saline soil with the water-stabilized base course 30. At the same time, the first gravel layer 220 can block the water-salt migration of the saline soil, so that sulfates cannot invade the water-stabilized base course 30 through water-salt migration.

[0041] Specifically, in the first gravel layer 220, gaps are created between adjacent gravels, giving the first gravel layer 220 large porosity and low capillary upwelling capacity, effectively limiting the transport of water and sulfates to the water-stabilized base course 30. Thus, moisture and sulfates cannot penetrate into the water-stabilized layer through the first gravel layer 220, reducing the risk of sulfate damage to the water-stabilized base course 30. Furthermore, due to its large porosity, the first gravel layer 220 itself does not easily form capillary upwelling channels, thus isolating moisture in the subgrade 10 to a certain extent, thereby reducing the opportunity for moisture and sulfates to migrate to the water-stabilized layer.

[0042] That is, the first gravel layer 220 prevents the migration of sulfate and water by means of physical barrier, and can structurally isolate the rise and penetration of sulfate, protecting the water-stabilized base layer 30 from the effects of sulfate-induced salt swelling.

[0043] According to some embodiments of the present invention, the porosity of the first gravel layer 220 is 13% to 16%, and the particle size of the gravel in the first gravel layer 220 is 5 mm to 40 mm.

[0044] By setting the porosity of the first gravel layer 220 to 13% to 16%, the first gravel layer 220 can possess good compactness while preventing sulfate from rising and penetrating into the water-stabilized base layer 30, thus preventing interlayer settlement or uneven compaction. By setting the particle size of the gravel in the first gravel layer 220 to 5mm to 40mm, the compactness and structural stability of the first gravel layer 220 can be improved by controlling the particle size. Smaller gravel particle sizes can better fill and tightly arrange, reducing voids and thus increasing the compactness of the first gravel layer 220, effectively preventing moisture and sulfate from penetrating into the water-stabilized base layer 30 through capillary action. At the same time, gravel of this particle size is more likely to form a uniform structure during paving, enhancing the compressive strength and load-bearing capacity of the first gravel layer 220 and ensuring the long-term stability of the road structure.

[0045] Specifically, in the first gravel layer 220, the gravel particle size ranges from 5mm to 10mm, 10mm to 20mm, and 20mm to 40mm. The aim is to ensure that the first gravel layer 220 has good compactness and structural stability while avoiding excessive fine particles from affecting the drainage and air permeability of the gravel layer.

[0046] See Figure 1 As shown, according to some embodiments of the present invention, the thickness of the backfill soil layer 210 is 20cm to 40cm, and the thickness of the first gravel layer 220 is 10cm to 20cm.

[0047] By setting the thickness of the backfill soil layer 210 to 20cm to 40cm, it can effectively block saline soil. Furthermore, setting the thickness of the gravel layer to 10cm to 20cm effectively enhances its impermeability, structural stability, and drainage. Appropriate thickness not only provides sufficient protection against moisture and sulfates rising and seeping into the underlying water-stabilized base course 30, but also improves the bearing capacity of the gravel layer, enhancing the overall stability of the road and preventing structural damage caused by uneven settlement. Simultaneously, a thicker gravel layer helps maintain good air permeability and drainage, preventing moisture accumulation and protecting the underlying structure from damage. In addition, appropriate thickness can improve road durability, resisting adverse effects from changes in the external environment, thereby extending the road's service life.

[0048] Specifically, the thickness of the backfill soil layer 210 can be 20cm, 30cm, 40cm, etc., and the thickness of the first gravel layer 220 can be 10cm, 15cm, 20cm, etc.

[0049] See Figure 2As shown, according to some embodiments of the present invention, the impermeable layer 20 includes a geotextile layer 230, a sand protection layer 240, and a second gravel layer 250. The geotextile layer 230 is laid on the roadbed 10, the sand protection layer 240 is laid on the geotextile layer 230, and the second gravel layer 250 is laid on the sand protection layer 240.

[0050] By setting the impermeable layer 20 as a geotextile layer 230, a sandy soil protective layer 240, and a second gravel layer 250, the geotextile layer 230 can block sulfates in the saline soil subgrade 10 from invading the water-stabilized base course 30, the sandy soil protective layer 240 can prevent the second gravel layer 250 from damaging the geotextile layer 230, and the second gravel layer 250 can effectively limit the transport of water and sulfates to the water-stabilized base course 30.

[0051] According to some embodiments of the present invention, the thickness of the second gravel layer 250 is 15cm to 25cm, and the thickness of the sand and soil protective layer 240 is 10cm to 20cm.

[0052] By setting the thickness of the second gravel layer 250 to 15cm to 25cm, the impermeability, structural stability, and drainage of the gravel layer can be effectively enhanced. By setting the thickness of the sand and soil protective layer 240 to 10cm to 20cm, it can be ensured that the sand and soil protective layer 240 can effectively protect the geotextile layer 230.

[0053] The porosity of the second gravel layer 250 is set to 13% to 16%, and the gravel particle size in the second gravel layer 250 is 5 mm to 40 mm.

[0054] Specifically, in the second gravel layer 250, the gravel particle size ranges from 5mm to 10mm, 10mm to 20mm, and 20mm to 40mm. The aim is to ensure that the second gravel layer 250 has good compactness and structural stability while avoiding excessive fine particles from affecting the drainage and air permeability of the gravel layer.

[0055] See Figure 3 As shown, according to some embodiments of the present invention, the impermeable layer 20 includes a third gravel layer 260, a guide pipe 270 is provided in the third gravel layer 260 at a downward inclination, a blind ditch 280 is provided on the side of the third gravel layer 260, the outlet end of the guide pipe 270 is connected to the blind ditch 280, and the guide pipe 270 is used to guide the sulfate in the third gravel layer 260 to the blind ditch 280.

[0056] By setting the impermeable layer 20 in the form of the third gravel layer 260, the diversion pipe 270 and the blind ditch 280, the third gravel layer 260 can restrict the transmission of water and sulfate to the water-stabilized base course 30. At the same time, the diversion pipe 270, which is set at an angle downward, can divert the water and sulfate in the saline soil subgrade 10 to the blind ditch 280 located on the side for collection, preventing the sulfate in the third gravel layer 260 from accumulating in large quantities and affecting the blocking effect.

[0057] According to some embodiments of the present invention, the side of the roadbed 10 is provided with a drainage ditch 50, and the outlet end of the blind ditch 280 is connected to the drainage ditch 50.

[0058] By setting up drainage ditches 50 on the side of roadbed 10, not only can the sulfate in blind ditch 280 be collected and treated, but also external sulfate can be prevented from eroding into the soil of roadbed 10.

[0059] In the third gravel layer 260, the gravel particle size and porosity are the same as those in the first gravel layer 220, and will not be described again.

[0060] See Figure 1 As shown, according to some embodiments of the present invention, the thickness of the water-stabilized base layer 30 is 30cm to 40cm.

[0061] By setting the thickness of the water-stabilized base course 30 to 30cm, the load-bearing capacity and stability of the road can be effectively improved. An appropriate thickness not only better distributes the load from the upper layer, reducing local settlement and maintaining road smoothness, but also provides sufficient compressive strength to ensure the strength and durability of the base course during long-term use. Furthermore, a reasonable thickness helps maintain the stability of the water-stabilized layer under different environmental conditions, avoiding expansion or contraction caused by moisture changes, and extending the road's service life. Therefore, setting the thickness of the water-stabilized base course 30 to 30cm can improve the overall road structure's compressive and impermeability performance, ensuring long-term stable road operation and reducing maintenance costs.

[0062] See Figure 1 As shown, according to some embodiments of the present invention, the road surface layer 40 is an asphalt road surface layer.

[0063] By designating pavement layer 40 as an asphalt pavement layer, the durability, smoothness, and comfort of the road can be significantly improved. Asphalt pavement has excellent compressive strength, crack resistance, and waterproofing properties, effectively resisting traffic loads, climate change, and moisture erosion. Asphalt pavement layers provide a smooth and comfortable driving experience, reducing noise and vibration, while also offering good drainage to minimize water damage to the pavement. Furthermore, asphalt pavement has a shorter construction cycle, is easy to maintain, and possesses good self-healing properties, capable of handling minor cracks and deformations to a certain extent.

[0064] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A road structure for preventing arching deformation, characterized in that, include: The roadbed, impermeable layer, water-stabilized base course, and pavement course are provided. The impermeable layer is laid on the roadbed, the water-stabilized base course is laid on the impermeable layer, and the pavement course is laid on the water-stabilized base course. The impermeable layer is used to prevent sulfates in the roadbed from penetrating into the water-stabilized base course. The impermeable layer includes a backfill soil layer and a first gravel layer, wherein the backfill soil layer is laid on the roadbed and the first gravel layer is laid on the backfill soil layer.

2. The road structure for preventing arching deformation according to claim 1, characterized in that, The porosity of the first gravel layer is 13% to 16%, and the particle size of the gravel in the first gravel layer is 5 mm to 40 mm.

3. The road structure for preventing arching deformation according to claim 1, characterized in that, The thickness of the backfill soil layer is 20cm to 40cm, and the thickness of the first gravel layer is 10cm to 20cm.

4. The road structure for preventing arching deformation according to claim 1, characterized in that, The impermeable layer includes a geotextile layer, a sandy soil protective layer, and a second gravel layer. The geotextile layer is laid on the roadbed, the sandy soil protective layer is laid on top of the geotextile layer, and the second gravel layer is laid on top of the sandy soil protective layer.

5. The road structure for preventing arching deformation according to claim 4, characterized in that, The second gravel layer has a thickness of 15cm to 25cm, and the sand and soil protective layer has a thickness of 10cm to 20cm.

6. The road structure for preventing arching deformation according to claim 1, characterized in that, The impermeable layer includes a third gravel layer, in which a flow guide pipe is inclined downwards. A blind trench is provided on the side of the third gravel layer. The outlet end of the flow guide pipe is connected to the blind trench. The flow guide pipe is used to guide the sulfate in the third gravel layer to the blind trench.

7. The road structure for preventing arching deformation according to claim 6, characterized in that, The side of the roadbed is provided with a drainage ditch, and the outlet end of the blind ditch is connected to the drainage ditch.

8. The road structure for preventing arching deformation according to any one of claims 1 to 7, characterized in that, The thickness of the water-stabilized base course is 30cm to 40cm, and the particle size of the coarse aggregate in the water-stabilized base course is less than or equal to 40mm.

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