Skid-resistant and durable cement concrete composite pavement structure

Abstract

The utility model relates to the technical field of pavement construction, in particular to an anti-skid durable cement concrete composite pavement structure which comprises a graded broken stone layer, a cement stabilized broken stone layer, an open graded drainage asphalt stabilized broken stone layer, a pouring type pavement layer, a mortar wet connection layer, a cement concrete lower layer and a cement concrete anti-skid surface layer. The surface layer adopts aggregates with different characteristics according to the service environment, so that high synergy of the characteristics of the aggregates and the service environment is realized, the anti-slide performance of the cement concrete surface layer is improved, the consumption of high-quality aggregates on the surface layer is reduced, the anti-scouring capability of the base layer is improved, the rigidity of the base layer is properly reduced, and the problems of surface layer cracks and plate breakage caused by base layer void are solved; the deformation resistance of the base layer is improved, the sensitivity to overload is reduced, and the bearing capacity of the pavement structure is obviously improved.

Description

Technical Field

[0001] The utility model relates to the technical field of road construction, in particular to a slip-resistant and durable cement concrete composite road surface structure. Background Art

[0002] The structure of cement concrete pavement is composed of cement concrete as the surface layer and various base layers, subbase layers and cushion layers. Cement concrete pavement is one of the important pavement structure forms in my country. It has the advantages of high rigidity, high strength, good stability, long service life and low construction cost throughout the whole cycle.

[0003] However, cement concrete pavement has the following problems: (1) The anti-skid performance decays at a fast rate. Studies have shown that the wear resistance of traditional limestone coarse aggregate is insufficient. The micro-texture on the aggregate surface and the macro-structure formed by the transverse grooves will be worn away in 3-4 years, which will lead to the pavement lateral force coefficient not meeting the specification requirements, seriously affecting traffic safety, especially in special climates such as rain and fog. (2) Cement concrete pavement has high requirements for the uniform support of its underlying layer and should have sufficient anti-scouring ability and appropriate rigidity. However, my country's traditional semi-rigid base layer has insufficient water scouring resistance. During service, under the coupling of water and traffic loads, the fine particles of the base mixture are easily released from the joints, resulting in the formation of voids around the joints of the road panels. The repeated action of traffic loads forms dynamic water pressure, which further aggravates the expansion of the void area. The voids in the base layer make it impossible to transfer the load downward. When the external load exceeds the bending and tensile strength of the surface layer, it will break. (3) The semi-rigid base layer has high rigidity, weak anti-deformation ability, and strong sensitivity to vehicle overload. It is easy to induce pavement cracks and broken boards, which seriously affects the durability of cement concrete pavement. To this end, improving the anti-skid properties of the surface layer, enhancing the anti-scouring ability of the base layer, and moderately reducing the stiffness of the base layer have become one of the key technologies for improving the durability of cement concrete pavements. Utility Model Content

[0004] The utility model aims to provide a slip-resistant and durable cement concrete composite pavement structure, aiming to solve the problems of rapid slip resistance decay of cement concrete pavements, insufficient anti-scouring ability of semi-rigid base layers, and high rigidity that seriously affect pavement durability.

[0005] To achieve the above-mentioned objectives, the utility model provides a skid-resistant and durable cement concrete composite pavement structure, comprising a graded gravel layer, a cement-stabilized gravel layer, an open-graded drainage asphalt-stabilized gravel layer, a cast-in-place pavement layer, a mortar wet joint layer, a cement concrete lower layer and a cement concrete skid-resistant surface layer, wherein the cement-stabilized gravel layer is laid on the graded gravel layer, the open-graded drainage asphalt-stabilized gravel layer is laid on the cement-stabilized gravel layer, the cast-in-place pavement layer is laid on the open-graded drainage asphalt-stabilized gravel layer, the mortar wet joint layer is laid on the cast-in-place pavement layer, the cement concrete lower layer is laid on the mortar wet joint layer, and the cement concrete skid-resistant surface layer is laid on the cement concrete lower layer.

[0006] The thickness of the open-graded drainage asphalt stabilized gravel layer is 60-100 mm, the binder is base asphalt, and the aggregate is steel slag and ore aggregate.

[0007] Among them, the thickness of the cast-in-place pavement layer is 60-80mm, the void ratio of the large-void asphalt mixture in the cast-in-place pavement material is 23-28%, the water-cement ratio of the cement-based grouting material is 0.3-0.45, the initial fluidity is less than 14s, the 20min fluidity is less than 22s, and the volume of the cement-based grouting material accounts for a percentage of the volume of the connected voids of the large-void asphalt mixture of not less than 85%.

[0008] The thickness of the mortar wet joint layer is 5-10 mm, the type of cement in the mortar wet joint layer is the same as that in the lower layer of cement concrete, and the water-cement ratio is the same as that of the cement-based grouting material in the cast-in-place pavement material.

[0009] The thickness of the lower layer of cement concrete is 180-240 mm, the cement strength grade is 42.5, and the aggregate can be one or more of recycled aggregate, steel slag, and limestone.

[0010] Among them, the anti-slip surface thickness of the cement concrete is 40-60mm, the coarse aggregate can be one or more of diabase, corundum, corundum and steel slag, the maximum nominal particle size is less than 13.2mm, the polishing value is greater than 42PSV, the crushing value is less than 18%, it contains at least 3 crushing surfaces, the apparent density is greater than 2800kg / m3, and the water expansion rate of steel slag is less than 1%.

[0011] The utility model discloses a skid-resistant and durable cement concrete composite pavement structure, which adopts a double-layer wet-jointed cement concrete high skid-resistant layer composed of the cement concrete lower layer and the cement concrete skid-resistant surface layer, uses the cast-in-place pavement layer material as the base layer, and utilizes the open-graded drainage asphalt stabilized gravel layer to effectively drain the internal moisture of the pavement structure. The surface layer adopts different characteristic aggregates according to the service environment, thereby achieving a high degree of coordination between the aggregate characteristics and the service environment, improving the skid-resistant performance of the cement concrete surface layer, reducing the consumption of high-quality surface aggregates, and at the same time improving the anti-scouring ability of the base layer and appropriately reducing its stiffness, solving the problems of surface layer cracks and broken plates caused by base layer delamination, improving the anti-deformation ability of the base layer, reducing the sensitivity to overload, and significantly improving the bearing capacity of the pavement structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art are briefly introduced below.

[0013] Figure 1 It is a structural schematic diagram of the anti-skid and durable cement concrete composite pavement structure of the first embodiment of the utility model.

[0014] In the figure: 101 - graded crushed stone layer, 102 - cement stabilized crushed stone layer, 103 - open-graded drainage asphalt stabilized crushed stone layer, 104 - cast-in-place pavement layer, 105 - mortar wet joint layer, 106 - cement concrete lower layer, 107 - cement concrete anti-skid surface layer. DETAILED DESCRIPTION

[0015] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0016] The first embodiment of the present application is:

[0017] See also Figure 1 ,in Figure 1 It is a structural schematic diagram of the anti-skid and durable cement concrete composite pavement structure of the first embodiment of the utility model.

[0018] The utility model provides a slip-resistant and durable cement concrete composite pavement structure, including a graded crushed stone layer 101, a cement stabilized crushed stone layer 102, an open-graded drainage asphalt stabilized crushed stone layer 103, a cast-in-place pavement layer 104, a mortar wet joint layer 105, a cement concrete lower layer 106, and a cement concrete slip-resistant surface layer 107. The above-mentioned solution solves the problems that the slip resistance of cement concrete pavement is rapidly attenuated, the semi-rigid base layer has insufficient anti-scouring ability, and the stiffness is relatively large, which seriously affect the pavement durability. It can be understood that the above-mentioned solution can be used in the case where the insufficient pavement durability needs to be solved.

[0019] In this embodiment, the surface layer structure is, from bottom to top, the graded crushed stone layer 101, the cement stabilized crushed stone layer 102, the open-graded drainage asphalt stabilized crushed stone layer 103, the cast-in-place pavement layer 104, the mortar wet joint layer 105, the cement concrete lower layer 106, and the cement concrete anti-skid surface layer 107. According to the requirements of pavement construction, the lower layer provides a working surface for the upper layer, and the construction order is from the lower layer to the upper layer.

[0020] The cement stabilized gravel layer 102 is laid on the graded gravel layer 101, the open-graded drainage asphalt stabilized gravel layer 103 is laid on the cement stabilized gravel layer 102, the cast-in-place pavement layer 104 is laid on the open-graded drainage asphalt stabilized gravel layer 103, the mortar wet joint layer 105 is laid on the cast-in-place pavement layer 104, the cement concrete lower layer 106 is laid on the mortar wet joint layer 105, the cement concrete anti-skid surface layer 107 is laid on the cement concrete lower layer 106, the graded gravel layer 101180mm aggregate is selected from one or more of recycled aggregate, steel slag, and ore aggregate, and the grading requirements are met. After the implementation of the gravel layer 101, the cement stabilized gravel layer 102 can be implemented, with a thickness of 180mm, and one or more of the aggregates such as recycled aggregate, steel slag, and ore aggregate need to meet the relevant grading requirements. After the cement stabilized gravel layer 102 is cured for a certain period of time, the modified emulsified asphalt is sprayed on its surface, and penetrates into the surface of the cement stabilized gravel layer 102 to a certain depth. The slurry sealing method is used to construct the sealing layer. After the sealing layer is implemented, the open-graded drainage asphalt stabilized gravel layer 103 is paved, with a thickness of 60mm, 70# matrix asphalt, steel slag: ore aggregate = 1:1. After the modified emulsified asphalt bonding layer is sprayed on the surface of the open-graded drainage asphalt stabilized gravel layer 103, the void ratio is 25%, and the thickness is paved. For 60mm large-void asphalt mixture, when the temperature of the mixture drops below 50℃, cement-based grouting material is constructed. The water-cement ratio of the grouting material is 0.35, the initial fluidity is 12s, and the 20min fluidity is less than 20s. The cement-based grouting material is allowed to fill the connected voids of the large-void asphalt mixture as much as possible, ensuring that the volume of the cement-based grouting material accounts for no less than 85% of the volume of the connected voids of the large-void asphalt mixture. After the cement-based grouting material is constructed, the cement mortar wet joint layer 105 can be configured. In order to ensure effective bonding between layers, the implementation time of the wet joint layer shall not be later than the final setting time of the cement-based grouting material. It is recommended to complete it at the initial setting time of the cement-based grouting material. The cement grade of the wet joint layer mortar is 42.5 , water-cement ratio is 0.35, the spraying thickness should be uniform, after the mortar wet joint layer 105 is implemented, the cement concrete lower layer 106 can be paved, the thickness is 200mm, the cement strength grade is 42.5, the mass ratio of recycled aggregate, steel slag and limestone is 1:1:2, in order to ensure that the lower layer and the anti-skid surface layer are bonded together, the surface of the lower layer should be rough, and the roughening method can be used. After the roughening of the cement concrete lower layer 106 and before the initial setting, the surface anti-skid layer is paved, with a thickness of 40mm. The coarse aggregate can be diabase, corundum, and steel slag. The maximum nominal particle size is less than 13.2mm, the polishing value is greater than 42PSV, the crushing value is less than 18%, it contains at least 3 crushing surfaces, and the apparent density is greater than 2800kg / m 3, the expansion rate of steel slag soaked in water is less than 1%. After paving, a 3m hanging ruler is used to rub the paddle so that the surface flatness, slurry thickness and workability meet the requirements of spreading wear-resistant coarse aggregate, and then the coarse aggregate pre-soaked with mortar is spread on the surface, and the roller is used to reciprocate and roll so that the coarse aggregate is embedded in the slurry, and finally scraped, roughened and covered. After curing for a specified time, the sawing, grouting and grooving form a macro structure. The coarse aggregate and groove structure embedded in the slurry finally provide good skid resistance for the road surface, so that aggregates with different characteristics are used in the surface layer according to the service environment, achieving a high degree of coordination between aggregate characteristics and service environment, improving the skid resistance of the cement concrete surface layer, reducing the consumption of high-quality aggregates in the surface layer, and at the same time improving the anti-scouring ability of the base layer and appropriately reducing its stiffness, solving the surface cracks and broken plates caused by the hollowing of the base layer, improving the anti-deformation ability of the base layer, reducing the sensitivity to overload, and significantly improving the bearing capacity of the pavement structure.

[0021] When using the anti-skid and durable cement concrete composite pavement structure of the present embodiment, a double-layer wet-jointed cement concrete high anti-skid layer composed of the cement concrete lower layer 106 and the cement concrete anti-skid surface layer 107 is adopted, the cast-in-place pavement layer 104 material is used as the base layer, and the open-graded drainage asphalt stabilized gravel layer 103 is used to effectively drain the internal moisture of the pavement structure, so that the surface layer adopts aggregates with different characteristics according to the service environment, thereby achieving a high degree of coordination between the aggregate characteristics and the service environment, improving the anti-skid performance of the cement concrete surface layer, reducing the consumption of high-quality aggregates in the surface layer, and at the same time improving the anti-scouring ability of the base layer and appropriately reducing its stiffness, solving the surface layer cracks and broken plates caused by base layer delamination, improving the base layer's anti-deformation ability, reducing the sensitivity to overload, and significantly improving the bearing capacity of the pavement structure.

[0022] What is disclosed above is only one or more preferred embodiments of the present application, and cannot be used to limit the scope of rights of the present application. Ordinary technicians in this field can understand that all or part of the processes of implementing the above embodiments and equivalent changes made according to the claims of the present application are still within the scope covered by the present application.

Claims

1. A slip-resistant and durable cement concrete composite pavement structure, characterized in that: It includes a graded crushed stone layer, a cement-stabilized crushed stone layer, an open-graded drainage asphalt-stabilized crushed stone layer, a cast-in-place pavement layer, a mortar wet joint layer, a cement concrete lower layer and a cement concrete anti-skid surface layer, the cement-stabilized crushed stone layer is laid on the graded crushed stone layer, the open-graded drainage asphalt-stabilized crushed stone layer is laid on the cement-stabilized crushed stone layer, the cast-in-place pavement layer is laid on the open-graded drainage asphalt-stabilized crushed stone layer, the mortar wet joint layer is laid on the cast-in-place pavement layer, the cement concrete lower layer is laid on the mortar wet joint layer, and the cement concrete anti-skid surface layer is laid on the cement concrete lower layer.

2. The anti-skid and durable cement concrete composite pavement structure according to claim 1, characterized in that: The thickness of the open-graded drainage asphalt stabilized gravel layer is 60-100 mm, the binder is base asphalt, and the aggregate is steel slag and ore aggregate.

3. The anti-skid and durable cement concrete composite pavement structure according to claim 1, characterized in that: The thickness of the mortar wet joint layer is 5-10mm, the type of cement in the mortar wet joint layer is the same as that of the cement concrete lower layer, and the water-cement ratio is the same as that of the cement-based grouting material in the cast-in-place pavement material.

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