Cement asphalt concrete pavement containing reinforcing layer

Abstract

The utility model relates to a cement asphalt concrete pavement containing a reinforcing layer, which comprises the reinforcing layer and a cement asphalt concrete layer, and the reinforcing layer is placed above the thickness of a concrete protection layer below the cement asphalt concrete layer; the reinforcing layer comprises a geogrid or a geogrid; the structure of the cement asphalt concrete road surface layer is a flat plate, and the reinforcing layer is placed above the thickness of the concrete protective layer; and the selection of the geogrid or the geogrid is determined according to the tensile force required during the design of the pavement slab reinforcement. After the cement asphalt concrete is hardened, the reinforcing layer is included to form a whole, and when the pavement slab bears a vertical load and generates a bending value, the reinforcing layer on the tension side of the pavement slab can bear tension, so that the pavement slab can be kept intact, and no tension crack is generated.

Description

Technical Field

[0001] This utility model relates to cement asphalt concrete pavement, and more specifically, to a cement asphalt concrete pavement containing a reinforcing layer. Background Technology

[0002] Cement asphalt concrete is laid on the road surface, which bears the load of vehicles and the bending force caused by temperature differences between the upper and lower surfaces, and generates bending tension on the bottom surface of the surface layer, such as... Figure 2 As shown. In pavement thickness design, the resilience modulus and tensile strength of the material are determined first, and the design parameters of each structural layer are confirmed. Then, the pavement thickness is calculated based on the design bending value. Finally, the tensile stress of the surface layer, subbase layer, and base layer of the road is checked to ensure they meet the allowable tensile stress requirements. When the road thickness is the same, the stronger the tensile strength of the road material, the lower the probability of tension cracks in the pavement subbase, and fewer cracks extend to the road surface. Besides causing discontinuities in the road structure, surface cracks will also enlarge due to repeated shear strain friction. Furthermore, surface runoff seeps into the subgrade through cracks, causing softening of the subgrade and subsequent damage and peeling of the asphalt concrete near the cracks, resulting in enlarged pavement holes. Therefore, to maintain the integrity of the road structure, it is necessary to suppress surface damage and inhibit the generation of tension cracks within the road structural layers. Summary of the Invention

[0003] To address the shortcomings of existing technologies, the purpose of this utility model is to provide a cement asphalt concrete pavement with a reinforcing layer. After the cement asphalt concrete hardens, the reinforcing layer forms a whole. When the pavement slab is subjected to vertical load and bending occurs, the reinforcing layer on the tension side of the pavement slab can withstand the tension, so that the pavement slab can remain intact and not produce tension cracks.

[0004] The above-mentioned technical objective of this utility model is achieved through the following technical solution:

[0005] A cement asphalt concrete pavement with a reinforcing layer includes a cement asphalt concrete layer and a reinforcing layer, wherein the reinforcing layer is positioned above the thickness of the concrete protective layer below the cement asphalt concrete layer.

[0006] In one embodiment, the reinforcing layer includes a geogrid or geogrid mesh.

[0007] In one embodiment, the cement asphalt concrete layer comprises the following components: silicate cement, fast-setting cationic emulsified asphalt, retarded liquid water-reducing agent, and crushed stone aggregate.

[0008] In one embodiment, the amount of fast-cracking cationic emulsified bitumen used is 0.9-1.5 times the weight of silicate cement.

[0009] In one embodiment, the amount of the retarding liquid water-reducing agent used is 2.5%-4% of the weight of silicate cement.

[0010] In summary, this utility model has the following beneficial effects:

[0011] This invention enables cement asphalt concrete to harden and form a whole with a reinforcing layer. When the road slab is subjected to vertical load and bends, the reinforcing layer on the tension side of the road slab can withstand the tension, so that the road slab can remain intact and not produce tension cracks. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the present invention.

[0013] Figure 2 This is the mechanism by which tensile stress is generated at the bottom of asphalt concrete.

[0014] Figure 3 This involves reinforcing existing roads with reinforced wire mesh (the image shows wire mesh).

[0015] Figure 4 For the overall slab structure design, the slab with a unit width is used as a beam for analysis and calculation.

[0016] Figure 5 Cement asphalt concrete slabs are designed with reinforcement in the form of beams.

[0017] Figure 1 In the middle: 1. Cement asphalt concrete, 2. Reinforcing layer. Detailed Implementation

[0018] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0019] It is worth noting that the directional terms such as "up" and "down" used in this article are all relative to the perspective of the attached figures and are only for the purpose of description. They should not be interpreted as limitations on the technical solutions.

[0020] like Figure 1 As shown, this utility model proposes a cement asphalt concrete pavement containing a reinforcing layer 2, including a cement asphalt concrete layer 1 and a reinforcing layer 2, wherein the reinforcing layer 2 is placed above the thickness of the concrete protective layer below the cement asphalt concrete layer 1.

[0021] In this invention, a protective layer of cement asphalt concrete layer 1 is laid and compacted on the road base. Before the protective layer of cement asphalt concrete layer 1 has initially set, a reinforcing layer 2 is laid as soon as possible. While the protective layer of the first layer of cement asphalt concrete has not yet initially set, a second layer of cement asphalt concrete is laid and compacted in layers. The reinforcing layer 2 can increase the tensile strength, reduce the bending stress of the road base, and allow the cement asphalt concrete to form a structure that can resist bending moments, preventing the tension from being transmitted to the road structure below.

[0022] The cement asphalt concrete layer 1 comprises the following components: silicate cement, fast-setting cationic emulsified asphalt, retarded liquid water-reducing agent and crushed stone aggregate. The amount of fast-setting cationic emulsified asphalt used is 0.9-1.5 times the weight of silicate cement, and the amount of retarded liquid water-reducing agent used is 2.5%-4% of the weight of silicate cement.

[0023] Preferably, the reinforcing layer 2 includes a geogrid or geomesh, the selection of which depends on the required tension of the road surface layer after design. When the required tensile force is large, the geogrid serves as a reinforcement. When the required tensile force is small, the geomesh serves as a reinforcement.

[0024] In existing technologies, the application of setting tension layers in road structural layers has precedents such as setting stiffening mesh on top of the subgrade or base course to suppress deflection. For example... Figure 3 As shown, laying wire mesh or geogrid / grid between the asphalt concrete layer and the inorganic mineral material or compacted original soil subgrade can increase the tension of the reinforcing layer by means of friction, thereby reducing the amount of deflection of the road layer under the reinforcing layer.

[0025] This invention involves incorporating tension stiffeners into cement asphalt concrete, thereby creating a slab structure capable of resisting positive bending moments and preventing the tension from being transmitted to the underlying road structure.

[0026] Cement asphalt concrete is a semi-rigid concrete material. Unlike hot-mix asphalt concrete made with asphalt oil, which is a viscoelastic material, its properties are closer to those of rigid cement concrete. Therefore, the road slabs paved with cement asphalt concrete are closer to cement concrete slabs in terms of material and mechanical properties. Thus, the structural and mechanical characteristics of cement concrete road slabs will be analyzed using the design methods of cement concrete road slabs.

[0027] Traditionally, the floor slabs of houses and the unit slabs of concrete pavements are made by dividing the slabs into unit widths, such as... Figure 4 Next, we will design and analyze it using rectangular beams, such as... Figure 5 In the design of rectangular concrete beams, the strain value ϵ of the concrete is generally set. cThe compressive strength of cement concrete is typically 30 MPa, while the mechanical properties of geogrids / grids are generally better, with strain values ​​between 0.02 and 0.05. The compressive strength of cement asphalt concrete is approximately 10 MPa. Formula 1 can be used to calculate the placement of the geogrid / grid and the spacing between its main sections. This invention utilizes geogrids / grids placed above the concrete protective layer of the cement asphalt concrete slab. This allows the geogrid / grid to bond and rub against the hardened cement asphalt concrete, resisting the tension generated at the bottom when the slab experiences deflection, inhibiting tension cracks at the bottom layer, ensuring the integrity of the slab, and extending its service life.

[0028] E c ×∈ c ×x×b÷2=E c ×∈ g ×b×(d-x)÷2=f g (Formula 1)

[0029] E c Young's modulus of cement asphalt concrete; f g Tensile strength of tension material

[0030] ∈ c : Compressive strain value of cement asphalt concrete; ∈ g Tensile strain value of cement asphalt concrete

[0031] b: Unit width; A: Tension material area; x: Height from top to neutral axis; d: Height from top to tension material.

[0032] The above description is merely a preferred embodiment of this utility model. The protection scope of this utility model is not limited to the above embodiments. All technical solutions falling within the scope of this utility model's concept are protected by this utility model. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principle of this utility model should also be considered within the protection scope of this utility model.

Claims

1. A cement asphalt concrete pavement containing a reinforcing layer, characterized in that, It includes a reinforcing layer (2) and a cement asphalt concrete layer (1), with the reinforcing layer (2) positioned above the thickness of the concrete protective layer below the cement asphalt concrete layer (1). The reinforcing layer (2) includes a geogrid or geogrid mesh; The cement asphalt concrete road surface layer has a flat plate structure, and the reinforcing layer (2) is placed above the thickness of the concrete protective layer. The selection of geogrid or geogrid depends on the tensile strength required in the road slab reinforcement design.

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