Anti-cracking cement concrete pavement composite structure

Abstract

The invention discloses an anti-cracking cement concrete pavement composite structure, and relates to the technical field of cement concrete pavement construction. Comprising a graded broken stone subbase layer, a cement stabilized macadam base layer is laid on the graded broken stone subbase layer, a modified asphaltic sand functional layer is laid on the cement stabilized macadam base layer, a cement concrete surface layer is laid on the modified asphaltic sand functional layer, and steel reinforcement frameworks are arranged in the cement concrete surface layer and the modified asphaltic sand functional layer. The steel reinforcement framework comprises a first-layer steel reinforcement mesh, U-shaped clamps, fasteners, a vertical steel reinforcement mesh and a second-layer steel reinforcement mesh, the first-layer steel reinforcement mesh is located in the modified asphalt sand functional layer, the second-layer steel reinforcement mesh is located in the cement concrete surface layer, and the first-layer steel reinforcement mesh and the second-layer steel reinforcement mesh are connected through the vertical steel reinforcement mesh. The connecting strength of the cement concrete surface layer and the modified asphaltic sand functional layer is improved, the structural strength of cracks of the cement concrete surface layer is enhanced, and the problem that the pavement is prone to cracking is solved.

Description

Technical Field

[0001] The invention relates to the technical field of cement concrete pavement construction, and more specifically to an anti-cracking cement concrete pavement composite structure. Background Art

[0002] Cement concrete pavement is one of the main pavement structures for high-grade highways. It has been rapidly developed due to its advantages such as high rigidity, good stability, strong bearing capacity and wear resistance. However, in the long-term operation process, due to the increase in traffic load, changes in temperature and humidity and other factors, cement concrete pavements often suffer from various problems such as cracking, misalignment, arching, potholes, etc. Among them, the most common and widespread disease is pavement cracking and damage, which directly affects the appearance of the pavement and even seriously affects the bearing capacity, durability and performance of the road.

[0003] The Chinese patent application number CN202011314646.9 discloses an asphalt pavement structure construction process, including the following steps: S1, paving a stable base layer; S2, paving a connecting structure; S3, paving an asphalt lower layer; S4, paving a reinforcement network; S5, paving an asphalt upper layer. The shortcomings of this patent are that the connecting structure and the reinforcement network are independent and do not form an overall network structure, which can easily cause the cement concrete surface layer bottom plate to be easily hollowed out, resulting in insufficient connection strength between the functional layer and the surface layer, causing pavement cracking.

[0004] At the same time, under the influence of vehicle load and temperature changes, stress concentration is inevitably generated on the base layer, cracks are generated, and with the repeated effects of vehicle load and temperature changes, the cracks extend through the surface layer, forming reflective cracks. As one of the most common manifestations of cement concrete pavement cracking, reflective cracks seriously reduce the service quality of the pavement.

[0005] Therefore, it is necessary to design a crack-resistant cement concrete pavement composite structure to solve the above technical problems. Summary of the invention

[0006] The purpose of the present invention is to provide a crack-resistant cement concrete pavement composite structure, which uses a steel skeleton to connect the modified asphalt sand functional layer and the cement concrete surface layer, thereby improving the continuity and connection strength of the pavement structure layer. At the same time, the arrangement of the vertical steel mesh enhances the structural strength of the cracks in the cement concrete surface layer, thereby reducing the cracking problem of the cement concrete pavement.

[0007] In order to achieve the above-mentioned object, the present invention adopts the following technical scheme: a crack-resistant cement concrete pavement composite structure, comprising a graded crushed stone subbase, a cement-stabilized crushed stone base is laid on the graded crushed stone subbase, a modified asphalt sand functional layer is laid on the cement-stabilized crushed stone base, a cement concrete surface layer is laid on the modified asphalt sand functional layer, and a steel skeleton is arranged in the cement concrete surface layer and the modified asphalt sand functional layer;

[0008] The steel skeleton includes a first layer of steel mesh, U-shaped clips, nails, a vertical steel mesh and a second layer of steel mesh. The first layer of steel mesh is located in the modified asphalt sand functional layer, the second layer of steel mesh is located in the cement concrete surface layer, and the first layer of steel mesh and the second layer of steel mesh are connected by the vertical steel mesh.

[0009] Preferably, the first layer of steel mesh and the vertical steel mesh are positionally constrained by a U-shaped clip, the U-shaped clip is provided with an interlocking hole for nail connection, the nail passes through the interlocking hole and is connected to the modified asphalt sand functional layer, and the vertical steel mesh is fixedly connected to the second layer of steel mesh by welding.

[0010] Preferably, the mesh holes of the first and second layers of steel mesh are both square holes, and the steel bar spacing is 150-200 mm; the vertical steel meshes are arranged at equal intervals, and the connection points of the vertical steel meshes are respectively located at the intersection of the grids of the first and second layers of steel mesh.

[0011] Preferably, the second layer of steel mesh is arranged between 1 / 3 and 1 / 2 of the thickness of the cement concrete surface layer on the side of the cement concrete surface layer close to the modified asphalt sand functional layer; the first layer of steel mesh is arranged on the surface layer of the modified asphalt sand functional layer.

[0012] Preferably, the mesh holes of the vertical steel mesh are triangular holes.

[0013] Preferably, the diameter of the steel bar is 6mm-10mm.

[0014] Preferably, the nail comprises a nail cap, a nail body is fixed on one side of the nail cap, a gasket is movably provided on the nail body, a plurality of elastic clamping rings are connected between the nail cap and the gasket, and the plurality of elastic clamping rings are evenly distributed between the nail cap and the gasket in a circular array.

[0015] Compared with the prior art, this patent has the following advantages:

[0016] 1. The present invention improves the connection strength between the modified asphalt sand functional layer and the cement concrete surface layer by setting a steel skeleton, especially a vertical steel mesh, so that the pavement structure layer is connected into a whole, which can effectively disperse the traffic load and impact force, thereby achieving the purpose of resisting cracking.

[0017] 2. The present invention ensures the continuity and density of the cement concrete surface layer by setting up vertical steel meshes arranged continuously and at equal intervals, thereby enhancing the structural strength of the cracks in the cement concrete surface layer, avoiding the continuous expansion of reflective cracks, and ensuring the service quality of the road surface.

[0018] 3. The present invention uses U-shaped clips and nails to connect the first layer of steel mesh and the vertical steel mesh, wherein the mutual cooperation between multiple elastic clips and the vertical steel mesh improves the bond strength between the steel skeleton and the concrete, enhances the overall structural strength of the cement concrete surface layer, and further improves its anti-cracking effect.

[0019] 4. The present invention can resist the stress caused by temperature change and concrete shrinkage by arranging vertical steel mesh and the second layer of steel mesh, and reduce cracks in concrete caused by temperature and shrinkage. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0021] Figure 2 It is a partial enlarged schematic diagram of the overall structure of the present invention;

[0022] Figure 3 It is a schematic diagram of the overall structure of the steel reinforcement skeleton of the present invention;

[0023] Figure 4 It is a schematic diagram of the U-shaped card structure of the present invention;

[0024] Figure 5 The schematic diagram of the nail shooting structure of the present invention is

[0025] Figure 6 It is a construction process flow chart of the present invention.

[0026] In the figure: 1. graded crushed stone subbase; 2. cement stabilized crushed stone base; 3. modified asphalt sand functional layer; 4. cement concrete surface layer; 5. steel skeleton; 51. second layer of steel mesh; 52. vertical steel mesh; 53. first layer of steel mesh; 54. U-shaped clip; 55. nail; 551. nail cap; 552. elastic clamp; 553. gasket; 554. nail body. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] Example 1

[0029] As attached Figure 1 As shown, a crack-resistant cement concrete pavement composite structure comprises a graded crushed stone subbase 1, a cement stabilized crushed stone base 2 is laid on the graded crushed stone subbase 1, a modified asphalt sand functional layer 3 is laid on the cement stabilized crushed stone base 2, a cement concrete surface layer 4 is laid on the modified asphalt sand functional layer 3, and a steel skeleton 5 is arranged in the cement concrete surface layer 4 and the modified asphalt sand functional layer 3;

[0030] Specifically, as attached Figure 2-Figure 4 As shown, the steel skeleton 5 includes a first layer of steel mesh 53, a U-shaped clip 54, a nail 55, a vertical steel mesh 52 and a second layer of steel mesh 51. The first layer of steel mesh 53 is located in the modified asphalt sand functional layer 3, and the second layer of steel mesh 51 is located in the cement concrete surface layer 4. The first layer of steel mesh 53 and the second layer of steel mesh 51 are connected by the vertical steel mesh 52. The steel mesh is an integral structure composed of steel bars with a diameter of 6 mm. The vertical steel mesh 52 connects the first layer of steel mesh 53 and the second layer of steel mesh 51 to form an integral network structure, which improves the connection strength between the modified asphalt sand functional layer 3 and the cement concrete surface layer 4, and connects the pavement structure layer into a whole.

[0031] More specifically, during construction, the nails 55 driven into the periphery of the U-shaped clip 54 are connected at the joint of the first layer of steel mesh 53 and the vertical steel mesh 52 through the U-shaped clip 54 and the nails 55, and the nails 55 can be firmly driven into the modified asphalt sand functional layer 3. The nails 55 and the U-shaped clip 54 are simple to operate and convenient to construct, and can effectively ensure the overall stability of the steel skeleton 5; the vertical steel mesh 52 and the second layer of steel mesh 51 are welded and fixedly connected. The first layer of steel mesh 53, the vertical steel mesh 52, and the second layer of steel mesh 51 used in the present invention are all prefabricated in the factory and directly laid on site, which improves the construction efficiency.

[0032] Refer to the attached Figure 6 As shown, a method for using a crack-resistant cement concrete pavement composite structure comprises the following steps:

[0033] S1. After the original ground is leveled and compacted, lay the graded crushed stone subbase 1, control the paving speed and thickness, and ensure that the flatness of the paving surface meets the design requirements. Then, clean up the debris and loose soil on the surface of the subbase to keep the surface clean and flat. Use a paver to lay the cement-stabilized crushed stone base 2 to ensure the continuity and uniformity of the paving.

[0034] S2. Lay a modified asphalt sand functional layer 3 on the cement-stabilized crushed stone base layer 2, and temporarily do not use a roller for compaction.

[0035] S3. Lay the first layer of steel mesh 53 flat on the modified asphalt sand functional layer 3. When the area of ​​a single steel mesh is insufficient, multiple steel meshes are spliced ​​together by tying with wires.

[0036] S4. Control the speed and number of passes of the roller to embed the first layer of steel mesh 53 into the modified asphalt sand functional layer 3 to ensure that it is firmly embedded. At the same time, the thickness, flatness, compactness and other indicators of the modified asphalt sand functional layer 3 are required to meet the requirements of the specification.

[0037] S5. Arrange vertical U-shaped cards 54, nails 55, vertical steel mesh 52 and the second layer of steel mesh 51, connect the first layer of steel mesh 53 and the vertical steel mesh 52 together through the U-shaped cards 54, and drive the nails 55 into the modified asphalt sand functional layer 3.

[0038] S6. Use a concrete mixer truck to transport cement concrete mixture, unload the concrete evenly on the functional layer, and spread it manually to control the paving thickness. Then, vibrate the corners with an inserted vibrator, and then vibrate the entire area with a flat vibrator. Finally, carry out construction processes such as leveling, plastering, curing, and cutting.

[0039] The practical principle of the anti-cracking cement concrete pavement composite structure in Example 1 of the present application is as follows: by setting a steel skeleton 5, especially a vertical steel mesh 52, the connection strength between the modified asphalt sand functional layer 3 and the cement concrete surface layer 4 is improved, so that the pavement structure layers are connected into a whole, which can effectively disperse the traffic load and impact force, thereby achieving the purpose of resisting cracking.

[0040] Example 2

[0041] Based on the above-mentioned embodiment 1, although the structure solves the problem of the connection strength between the modified asphalt sand functional layer 3 and the cement concrete surface layer 4, at the same time, under the traffic load and temperature changes, stress concentration is inevitably generated on the base layer, cracks are generated, and with the repeated effects of the traffic load and temperature changes, the cracks extend through the surface layer to form reflective cracks, which seriously reduce the road service quality. Based on the above technical problems, the following embodiment 2 is proposed.

[0042] Specifically, as attached Figure 2-Figure 4 As shown, the first layer of steel mesh 53 and the second layer of steel mesh 51 are arranged in parallel, and the mesh holes of the first layer of steel mesh 53 and the second layer of steel mesh 51 are both square holes, and the spacing between the steel bars is 200 mm. The second layer of steel mesh 51 is arranged at 1 / 2 thickness of the cement concrete surface layer 4 on the side of the cement concrete surface layer 4 close to the modified asphalt sand functional layer 3. The first layer of steel mesh 53 is arranged on the surface layer of the modified asphalt sand functional layer 3. The arrangement of the double-layer steel mesh enhances the tensile strength and bearing capacity of the cement concrete pavement.

[0043] Furthermore, a vertical steel mesh 52 with a spacing of 200 mm is vertically arranged between the first steel mesh 53 and the second steel mesh 51, and the connection points of the vertical steel mesh 52 are respectively located at the intersection of the grids of the first steel mesh 53 and the second steel mesh 51. The vertical steel mesh 52 is a continuous wavy steel bar bent by a steel bending machine, and is combined with the first steel mesh 53 and the second steel mesh 51 to form a triangular mesh.

[0044] At the same time, because the reflected cracks are generally transverse cracks, a vertical steel mesh 52 is set parallel to the driving direction of the road. In the prior art, the vertical steel bars are isolated from each other and no continuous steel network is formed. When the cracks in the base layer are reflected to the surface layer, the surface layer is prone to cracking and damage between the vertical steel bars. In the present invention, the vertical steel mesh 52 is arranged continuously to ensure the continuity and compactness of the cement concrete surface layer 4. When the cracks in the base layer extend through the cement concrete surface layer 4, a large concentrated stress is generated at the cracks in the cement concrete surface layer 4. At this time, the setting of the vertical steel mesh 52 enhances the structural strength of the cracks in the cement concrete surface layer 4, prevents the cracks from continuing to extend to the road surface, and ensures the service quality of the road surface.

[0045] Example 3

[0046] As attached Figure 5 As shown, in order to ensure that the nail 55 is firmly connected to the asphalt sand functional layer 3, a nail cap 551 is provided on the top of the nail 55, a nail body 554 is fixedly provided at one end of the nail cap 551, a gasket 553 is movably provided on the nail body 554, a plurality of elastic clamping rings 552 are connected between the nail cap 551 and the gasket 553, and the plurality of elastic clamping rings 552 are evenly distributed in a circular array between the nail cap 551 and the gasket 553, and the nails 55 are respectively arranged around the U-shaped clamp 54.

[0047] It should be noted that there is friction between the gasket 553 and the nail body 554, and only when the external pressure is sufficient will the gasket 553 move relative to the nail body 554. When the gasket 553 moves, it will drive the elastic clamping ring 552 to bend, causing the diameter of the elastic clamping ring 552 after bending to be larger than the diameter of the nail cap 551.

[0048] When the nail 55 is in use, the nail cap 551 is struck repeatedly to apply pressure, so that the nail body 554 passes through the U-shaped card 54 and penetrates into the asphalt sand functional layer 3. At this time, the gasket 553 does not contact the U-shaped card 54, and as the nail body 554 penetrates, the gasket 553 and the U-shaped card 54 come into conflict. At the same time, the nail cap 551 is still struck continuously to promote relative movement between the gasket 553 and the nail body 554, so that the elastic clamp ring 552 is bent and deformed, and at the same time, the gasket 553 is pressed against the U-shaped card 554 under the elastic pressure of the elastic clamp ring 552. 4. During the use of the steel skeleton 5, the influence of the working vibration of the construction equipment on the connection strength between the nail 55 and the U-shaped clip 54 is reduced. That is, when the external environment vibrates, the U-shaped clip 54 will be driven to vibrate, and the gasket 553 will be driven to vibrate, prompting the elastic clamp ring 552 to move elastically, thereby reducing the vibration force transmitted to the nail cap 551, thereby improving the connection strength of the nail body 554, and further improving the connection strength between the asphalt sand functional layer 3 and the cement concrete surface layer 4, avoiding the problem of easy disturbance and displacement of the steel skeleton 5 during construction.

[0049] Furthermore, after the nail cap 551 fixes the steel skeleton 5, the middle positions of the multiple elastic clamps 552 are bent toward the side away from the nail body 554, causing the elastic clamps 552 to form a hollow shape, and then through the mutual cooperation between the elastic clamps 552 and the vertical steel mesh 52, the bond strength between the steel skeleton 55 and the concrete is improved, thereby enhancing the overall structural strength of the cement concrete surface layer 4 and further improving its anti-cracking effect.

[0050] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A crack-resistant cement concrete pavement composite structure, comprising a graded crushed stone subbase (1), a cement-stabilized crushed stone base (2) laid on the graded crushed stone subbase (1), a modified asphalt sand functional layer (3) laid on the cement-stabilized crushed stone base (2), and a cement concrete surface layer (4) laid on the modified asphalt sand functional layer (3), characterized in that: A steel skeleton (5) is arranged in the cement concrete surface layer (4) and the modified asphalt sand functional layer (3); The steel skeleton (5) comprises a first layer of steel mesh (53), U-shaped clips (54), nails (55), a vertical steel mesh (52) and a second layer of steel mesh (51); the first layer of steel mesh (53) is located in the modified asphalt sand functional layer (3); the second layer of steel mesh (51) is located in the cement concrete surface layer (4); and the first layer of steel mesh (53) and the second layer of steel mesh (51) are connected via the vertical steel mesh (52).

2. The anti-cracking cement concrete pavement composite structure according to claim 1, characterized in that: The first layer of steel mesh (53) and the vertical steel mesh (52) are positionally constrained by a U-shaped clip (54); the U-shaped clip (54) is provided with an interlocking hole for connecting with a nail (55); the nail (55) passes through the interlocking hole and is connected to the modified asphalt sand functional layer (3); and the vertical steel mesh (52) and the second layer of steel mesh (51) are fixedly connected by welding.

3. The anti-cracking cement concrete pavement composite structure according to claim 1, characterized in that: The mesh holes of the first layer of steel mesh (53) and the second layer of steel mesh (51) are both square holes, and the spacing between the steel bars is 150 to 200 mm; The vertical steel meshes (52) are arranged at equal intervals, and the connection points of the vertical steel meshes (52) are respectively located at the intersection of the meshes of the first layer of steel mesh (53) and the second layer of steel mesh (51).

4. The anti-cracking cement concrete pavement composite structure according to claim 1, characterized in that: The second layer of steel mesh (51) is arranged between 1 / 3 and 1 / 2 of the thickness of the cement concrete surface layer (4) on the side of the cement concrete surface layer (4) close to the modified asphalt sand functional layer (3); The first layer of steel mesh (53) is arranged on the surface layer of the modified asphalt sand functional layer (3).

5. The anti-cracking cement concrete pavement composite structure according to claim 3, characterized in that: The mesh holes of the vertical steel mesh (52) are triangular holes.

6. The anti-cracking cement concrete pavement composite structure according to claim 1, characterized in that: The diameter of the steel bar is 6mm-10mm.

7. The anti-cracking cement concrete pavement composite structure according to claim 1, characterized in that: The nail (55) comprises a nail cap (551), a nail body (554) is fixed on one side of the nail cap (551), a gasket (553) is movably provided on the nail body (554), a plurality of elastic clamping rings (552) are connected between the nail cap (551) and the gasket (553), and the plurality of elastic clamping rings (552) are evenly distributed in a circular array between the nail cap (551) and the gasket (553).

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