A high-speed roadbed structure

Abstract

The present invention relates to the technical field of road structures, and more specifically, it relates to a high-speed roadbed structure, comprising an express roadbed, an intermediate roadbed and a slow roadbed, wherein the bearing performance of the express roadbed, the intermediate roadbed and the slow roadbed increases in sequence, the pavement flatness of the express roadbed, the intermediate roadbed and the slow roadbed decreases in sequence, and the drainage performance of the express roadbed, the slow roadbed and the intermediate roadbed decreases in sequence. The high-speed roadbed structure of the present invention enables the bearing performance, drainage performance and pavement drainage of the express roadbed, the intermediate roadbed and the slow roadbed to meet their respective actual needs, prevents performance overflow, and thus reduces construction costs.

Description

Technical Field

[0001] The invention relates to the technical field of road structures, in particular to a high-speed roadbed structure. Background Art

[0002] The subgrade structure of a highway is an important part to ensure its bearing capacity, stability and durability. As the foundation of the highway, the subgrade mainly bears the load from the road surface and vehicles and transfers it to the soil layer below.

[0003] On highways, different types of vehicles have different design speeds and acceleration capabilities. In order to ensure driving safety, it is necessary to separate relatively fast vehicles from relatively slow vehicles to prevent traffic conflicts caused by speed differences. Therefore, highways are divided into fast lanes, middle lanes and slow lanes. Usually, the fast lane is mostly used for cars, the slow lane is mostly used for large trucks, and the middle lane is between the two. In the prior art, the fast lanes, middle lanes and slow lanes of highways are often constructed in a unified manner, so that the fast lanes, middle lanes and slow lanes are all the same roadbed structure, with the same bearing performance, drainage performance, road surface flatness and other performance. However, the actual performance requirements required by different lanes are often different. For example, the fast lane requires a higher road surface flatness to ensure that the vehicles traveling at high speed on the fast lane can remain stable, and the slow lane requires a higher bearing performance to ensure that the slow lane can bear the weight of large vehicles for a long time. In addition, the fast lane and the slow lane are edge lanes, which are more prone to water accumulation than the middle lane, so better drainage performance is required to avoid water accumulation affecting the safe driving of vehicles. To sum up, if the fast lane, middle lane and slow lane on the highway have the same roadbed structure, it is easy to cause performance overflow of some lanes, thereby greatly increasing the construction cost, or cause insufficient performance of some lanes, thus affecting the service life. Summary of the invention

[0004] In order to solve the problems existing in the prior art, the present application provides a high-speed roadbed structure.

[0005] The present invention provides a high-speed roadbed structure adopting the following technical solution:

[0006] A high-speed roadbed structure comprises an express roadbed, an intermediate roadbed and a slow roadbed, wherein the bearing capacities of the express roadbed, the intermediate roadbed and the slow roadbed increase in sequence, the road surface flatness of the express roadbed, the intermediate roadbed and the slow roadbed decreases in sequence, and the drainage performance of the express roadbed, the slow roadbed and the intermediate roadbed decreases in sequence.

[0007] Preferably, the expressway roadbed, the intermediate roadbed and the slowway roadbed all include a base layer, a crushed stone layer, a concrete layer and an asphalt layer in sequence from bottom to top.

[0008] Preferably, the structures and materials of the subgrades of the expressway roadbed, the intermediate roadbed and the slowway roadbed are the same.

[0009] Preferably, the bottom surface of the gravel layer is connected to a drainage pipe, and the gravel particle sizes of the expressway roadbed, the slowway roadbed and the intermediate roadbed decrease in sequence.

[0010] Preferably, an impermeable membrane is provided between the gravel layer and the base layer, and the impermeable membranes of the express roadbed, the slow roadbed and the intermediate roadbed are respectively made of HDPE impermeable membrane, LDPE impermeable membrane and EVA impermeable membrane.

[0011] Preferably, the concrete layers of the slow carriageway roadbed, the intermediate carriageway roadbed and the fast carriageway roadbed are respectively added with steel fibers, mineral admixtures and polymer fibers.

[0012] Preferably, the compaction times of the asphalt layers of the expressway roadbed, the intermediate roadbed and the slowway roadbed decrease successively.

[0013] Preferably, the base layers of the express roadbed, the intermediate roadbed and the slow roadbed are constructed uniformly to form an integrated base layer, and the gravel layer, the concrete layer and the asphalt layer between the express roadbed, the intermediate roadbed and the slow roadbed are constructed independently.

[0014] Preferably, joint sections are provided between the expressway roadbed and the intermediate roadbed, and between the slowway roadbed and the intermediate roadbed, and the joint material of the joint sections is epoxy resin.

[0015] Preferably, on the outside of the expressway roadbed and the outside of the slowway roadbed, a sewer pipe is pre-buried between the top surface of the asphalt layer and the top surface of the gravel layer, and a filter plate is provided on the top of the sewer pipe.

[0016] The beneficial effects of the present invention are:

[0017] 1. The drainage effects of the expressway roadbed, slowway roadbed and intermediateway roadbed can better meet the actual drainage performance required by each, prevent the drainage performance from overflowing, and save the construction cost of the gravel layer of the roadbed;

[0018] 2. The bearing effects of the expressway roadbed, the intermediate roadbed and the slowway roadbed can better meet the actual bearing performance required by each, prevent the bearing performance from overflowing, and save the construction cost of the concrete layer of the roadbed;

[0019] 3. The expressway roadbed, the intermediate roadbed and the slowway roadbed can better meet the actual road surface flatness requirements of each, and prevent the performance overflow of the road surface flatness, saving some labor costs and ultimately saving the construction cost of the asphalt layer of the roadbed. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a cross-sectional view of the highway roadbed structure in an embodiment of the present application.

[0021] Explanation of the accompanying reference numerals: 1. Expressway roadbed; 2. Intermediate roadbed; 3. Slowway roadbed; 41. Base layer; 42. Anti-seepage membrane; 43. Gravel layer; 44. Concrete layer; 45. Asphalt layer; 5. Joint section; 6. Sewer pipe; 7. Drainage pipe; 8. Marking. DETAILED DESCRIPTION

[0022] The following will be combined with the attached Figure 1 The present invention is further illustrated by the following embodiments.

[0023] This embodiment discloses a high-speed roadbed structure.

[0024] Reference Figure 1 The high-speed roadbed structure includes an expressway roadbed 1, an intermediate lane roadbed 2 and a slow lane roadbed 3. Since most of the vehicles running on the express lane are small cars and most of the vehicles running on the slow lane are large trucks, and the average weight of the vehicles running on the intermediate lane is between the express lane and the slow lane, the slow lane roadbed 3 has the highest load-bearing performance, the intermediate lane roadbed 2 has the second highest load-bearing performance, and the expressway roadbed 1 has the lowest load-bearing performance. In order to meet the above-mentioned differences in load-bearing performance requirements, in the present invention, the load-bearing performance of the expressway roadbed 1, the intermediate lane roadbed 2 and the slow lane roadbed 3 increases in sequence.

[0025] Reference Figure 1 Since small cars traveling in the fast lane are faster, large trucks traveling in the slow lane are slower, and the average speed of vehicles traveling in the middle lane is between the fast lane and the slow lane, the road surface flatness required by the fast lane roadbed 1 is the highest, the road surface flatness required by the middle lane roadbed 2 is the second highest, and the road surface flatness required by the slow lane roadbed 3 is the lowest. In order to meet the above-mentioned difference in bearing performance, in the present invention, the road surface flatness of the fast lane roadbed 1, the middle lane roadbed 2 and the slow lane roadbed 3 decreases in sequence.

[0026] Reference Figure 1In road design, the middle is usually higher than the two sides, and vehicles tend to splash water to the left and right sides when driving. Therefore, the water in the fast lane and the slow lane is usually more than that in the middle lane, that is, the fast lane roadbed 1 and the slow lane roadbed 3 need to have higher drainage performance than the middle lane. In addition, since the vehicles in the fast lane travel at a faster speed, the accumulated water poses a greater safety hazard to the vehicles traveling in the fast lane. Therefore, the drainage performance required by the fast lane roadbed 1 is higher than that required by the slow lane roadbed 3. In order to meet the above-mentioned difference in drainage performance, in the present invention, the drainage performance of the fast lane roadbed 1, the slow lane roadbed 3 and the middle lane roadbed 2 decreases in sequence.

[0027] Reference Figure 1 The express roadbed 1, the intermediate roadbed 2 and the slow roadbed 3 all include a base layer 41, a crushed stone layer 43, a concrete layer 44 and an asphalt layer 45 from bottom to top. The base layer 41, as the bottom structure of the roadbed, is composed of high-strength compressed soil to ensure its structural stability and not prone to collapse. In order to form high-strength compressed soil, it is necessary to use multiple compaction methods for compression. In this embodiment, the structure and material of the base layer 41 of the express roadbed 1, the intermediate roadbed 2 and the slow roadbed 3 are the same.

[0028] Reference Figure 1The gravel layer 43 is composed of gravel blocks, and a drainage pipe 7 is connected to the bottom surface of the gravel layer 43. An impermeable membrane 42 is arranged between the gravel layer 43 and the base layer 41. The gravel layer 43 not only provides a certain bearing capacity, but also has a drainage function, because the gaps between the gravel layers 43 are easy for infiltrated water or groundwater to flow, and finally the infiltrated water is discharged through the drainage pipe 7 on the bottom surface of the gravel layer 43. In this process, the impermeable membrane 42 between the gravel layer 43 and the base layer 41 is used to prevent the infiltrated water from further infiltrating into the base layer 41, thereby protecting the base layer 41. In this embodiment, the crushed stone particle sizes of the express roadbed 1, the slow roadbed 3 and the intermediate roadbed 2 are successively reduced, so that the drainage effect and cost are successively reduced. It should be noted that the larger the crushed stone particle size, the larger the gaps forming the crushed stone layer 43, thereby having a better water seepage effect. However, at the same time, since the gaps generated when large pieces of crushed stone are piled up are larger, the weight of crushed stone that can be transported in the same size of transportation space is lower, resulting in an increase in transportation costs, and ultimately an increase in the cost of using large-diameter crushed stone. In addition, the mining cost and processing cost of large-diameter crushed stone are also higher. Therefore, as the crushed stone particle size decreases, the drainage effect and cost of the crushed stone layer 43 will successively decrease. In this embodiment, the anti-seepage membranes 42 of the express roadbed 1, the slow roadbed 3 and the intermediate roadbed 2 are respectively HDPE anti-seepage membrane 42 (high-density polyethylene geomembrane), LDPE anti-seepage membrane 42 (low-density polyethylene geomembrane) and EVA anti-seepage membrane 42 (ethylene-vinyl acetate copolymer geomembrane), so that the anti-seepage effect and cost between the gravel layer 43 and the base layer 41 of the express roadbed 1, the slow roadbed 3 and the intermediate roadbed 2 are reduced successively. Through the above settings, the drainage effect of the express roadbed 1, the slow roadbed 3 and the intermediate roadbed 2 can better meet the actual drainage performance required by each, and prevent the drainage performance from overflowing, saving the construction cost of the gravel layer 43 of the roadbed.

[0029] Reference Figure 1, the concrete layer 44 is cast by concrete, and the concrete layer 44 plays a major bearing effect on the roadbed. In this embodiment, the concrete layers 44 of the slow roadbed 3, the intermediate roadbed 2 and the express roadbed 1 are respectively added with steel fibers, mineral admixtures and polymer fibers. After the steel fibers are added to the concrete layer 44 of the slow roadbed 3, the steel fibers are evenly distributed in the concrete to form a mesh structure, which effectively prevents the expansion of concrete cracks and improves the overall bearing capacity. After the concrete layer 44 of the intermediate roadbed 2 is added with mineral admixtures such as silica fume and fly ash, the density and durability of the concrete can be improved, thereby improving the bearing capacity, and the effect is lower than that of steel fibers. After the polymer fibers such as polypropylene fibers and polyester fibers are added to the express roadbed 1, the crack resistance and durability of the concrete can be improved, thereby improving the bearing capacity, but the effect is lower than that of mineral admixtures. In addition, the costs of steel fibers, mineral admixtures and polymer fibers are reduced in turn. Therefore, through the above settings, the bearing effects of the express roadbed 1, the intermediate roadbed 2 and the slow roadbed 3 can better meet their respective actual required bearing performance, prevent the bearing performance from overflowing, and save the construction cost of the concrete layer 44 of the roadbed.

[0030] Reference Figure 1 The asphalt layer 45 serves as the surface layer of the roadbed for direct contact with the tires of vehicles on the expressway. In this embodiment, the compaction times of the asphalt layers 45 of the express roadbed 1, the intermediate roadbed 2 and the slow roadbed 3 are successively reduced, so that the express roadbed 1, the intermediate roadbed 2 and the slow roadbed 3 can better meet the road surface flatness actually required by each of them, and prevent the performance overflow of the road surface flatness, save part of the labor cost, and finally save the construction cost of the asphalt layer 45 of the roadbed.

[0031] Reference Figure 1 Since the base layers 41 of the express roadbed 1, the intermediate roadbed 2 and the slow roadbed 3 are the same, the base layers 41 of the express roadbed 1, the intermediate roadbed 2 and the slow roadbed 3 are constructed uniformly to form an integrated base layer 41. Then, a template is set up on the base layer 41 to separate the remaining layers of the express roadbed 1, the intermediate roadbed 2 and the slow roadbed 3, and then the construction is carried out independently after separation. After the construction of each asphalt layer 45 is completed, the template is removed, and the joints between the express roadbed 1 and the intermediate roadbed 2 and between the slow roadbed 3 and the intermediate roadbed 2 are treated to form a joint section 5 located on the base layer 41. In this embodiment, epoxy resin is selected as the joint material of the joint section 5 for the following reasons: on the one hand, epoxy resin has excellent strength and chemical resistance, and can fill or form a solid joint; on the other hand, the markings 8 of different lanes of the highway will be drawn on the top surface of the joint, and the smooth surface of epoxy resin can effectively improve the adhesion and wear resistance of the markings 8, thereby reducing the peeling of the markings 8.

[0032] Reference Figure 1 In order to further improve the drainage performance of the express roadbed 1 and the slow roadbed 3 and reduce water accumulation, in this embodiment, a downpipe 6 is pre-buried between the top surface of the asphalt layer 45 and the top surface of the gravel layer 43 on the outside of the express roadbed 1 and the outside of the slow roadbed 3, so that the accumulated water on the surface of the express roadbed 1 and the slow roadbed 3 can enter the gravel layer 43 from the downpipe 6 and be discharged. Furthermore, a filter plate is arranged on the top of the downpipe 6, which not only plays a water filtering effect, but also plays an effect of keeping the surface of the asphalt layer 45 flat.

[0033] The above are all preferred embodiments of the present invention, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A high-speed roadbed structure, characterized in that: The invention comprises an express roadbed (1), an intermediate roadbed (2) and a slow roadbed (3), wherein the bearing capacity of the express roadbed (1), the intermediate roadbed (2) and the slow roadbed (3) increases in sequence, the road surface flatness of the express roadbed (1), the intermediate roadbed (2) and the slow roadbed (3) decreases in sequence, and the drainage performance of the express roadbed (1), the slow roadbed (3) and the intermediate roadbed (2) decreases in sequence; The express roadbed (1), the intermediate roadbed (2) and the slow roadbed (3) all include, from bottom to top, a base layer (41), a crushed stone layer (43), a concrete layer (44) and an asphalt layer (45); The bottom surface of the gravel layer (43) is connected to a drainage pipe (7), and the gravel particle sizes of the express roadbed (1), the slow roadbed (3) and the intermediate roadbed (2) decrease in sequence; An impermeable membrane (42) is arranged between the gravel layer (43) and the base layer (41), and the impermeable membranes (42) of the express roadbed (1), the slow roadbed (3) and the intermediate roadbed (2) are respectively made of HDPE impermeable membrane (42), LDPE impermeable membrane (42) and EVA impermeable membrane (42); The concrete layers (44) of the slow roadbed (3), the intermediate roadbed (2) and the fast roadbed (1) are respectively added with steel fibers, mineral admixtures and polymer fibers; A joint section (5) is provided between the express roadbed (1) and the intermediate roadbed (2), and between the slow roadbed (3) and the intermediate roadbed (2). The joint material of the joint section (5) is epoxy resin.

2. A highway roadbed structure according to claim 1, characterized in that: The structure and material of the subgrade (41) of the express roadbed (1), the intermediate roadbed (2) and the slow roadbed (3) are the same.

3. A highway roadbed structure according to claim 2, characterized in that: The compaction times of the asphalt layers (45) of the expressway roadbed (1), the intermediate roadbed (2) and the slowway roadbed (3) decrease in sequence.

4. A high-speed roadbed structure according to claim 3, characterized in that: The base layers (41) of the express roadbed (1), the intermediate roadbed (2) and the slow roadbed (3) are constructed uniformly to form an integrated base layer (41), and the crushed stone layer (43), the concrete layer (44) and the asphalt layer (45) between the express roadbed (1), the intermediate roadbed (2) and the slow roadbed (3) are constructed independently.

5. A high-speed roadbed structure according to claim 4, characterized in that: On the outside of the express roadbed (1) and the outside of the slow roadbed (3), a sewer pipe (6) is pre-buried between the top surface of the asphalt layer (45) and the top surface of the gravel layer (43), and a filter plate is provided on the top of the sewer pipe (6).

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