Method and equipment for judging total thickness of pavement structure based on frost heaving amount

Abstract

The invention relates to a method and equipment for judging the total thickness of a pavement structure based on the frost heaving amount, the thickness and thermophysical property coefficient of each layer of a pavement can be obtained, the thickness of a soil base layer is an assumed freezing thickness, and a comprehensive thermophysical property coefficient is obtained through calculation; calculating the maximum freezing depth of the pavement; calculating the thickness of the pavement structure layer; calculating the freezing depth of the soil base layer; if the freezing depth of the soil base layer is not equal to the assumed freezing thickness, replacing the assumed freezing thickness of the soil base layer with the freezing depth of the soil base layer, and repeating the operation; according to the freezing depth of the soil base layer and the average frost heaving rate of soil, the soil base frost heaving amount is calculated; and judging whether the soil base frost heaving amount is smaller than the permissible frost heaving height of the pavement or not, and outputting a judgment result. It can be understood that the technical scheme shown by the invention is suitable for quantitative judgment of the thickness of the structural layers of airports, highway cement concrete pavements and asphalt concrete pavements, and the vacancy of quantitative calculation and judgment of the total structural layer thickness of the pavements is supplemented.

Description

Technical Field

[0001] The present invention relates to the technical field of pavement structures, and in particular to a method and device for determining the total thickness of a pavement structure based on frost heave. Background Art

[0002] Pavement structures are all very important. For example, the pavement engineering of the airport flight area is the most important infrastructure of the airport and one of the projects with the highest investment in airport engineering. The pavement not only bears the load of the aircraft, but is also affected by the environment such as temperature and water. Especially in frozen areas, the antifreeze of the pavement is particularly important. If the thickness of the antifreeze layer of the pavement structure is not enough, it will affect the use of the pavement and affect flight safety.

[0003] In the current pavement specifications, the antifreeze requirements for the pavement structure layer are only stipulated from a qualitative perspective, that is, different frost heave depths correspond to the minimum antifreeze layer thickness, but there is no corresponding calculation method to determine the total thickness of the pavement structure based on the amount of frost heave. Summary of the invention

[0004] In view of this, an object of the present invention is to provide a method and device for determining the total thickness of a pavement structure based on the amount of frost heave, so as to solve the problem that the prior art only specifies the antifreeze requirements of the pavement structure layer from a qualitative perspective.

[0005] According to a first aspect of an embodiment of the present invention, a method for determining the total thickness of a pavement structure based on frost heave is provided, comprising: S11, obtaining the thickness and thermophysical coefficient of each layer in the pavement structure layer, obtaining the assumed freezing thickness and thermophysical coefficient of the soil base layer, and calculating the comprehensive thermophysical coefficient according to the thickness and thermophysical coefficient of each layer; S12, calculating the maximum freezing depth of the road surface according to the comprehensive thermal physical property coefficient, the preset roadbed humidity coefficient, the preset roadbed cross-sectional form coefficient and the earth standard freezing depth; S13, calculating the thickness of the pavement structure layer according to the thickness of each layer in the pavement structure layer; S14, calculating the freezing depth of the soil base layer according to the maximum freezing depth of the road surface and the thickness of the road surface structure layer; S15, judging whether the freezing depth of the soil base layer is equal to the assumed freezing thickness; if not, replacing the assumed freezing thickness of the soil base layer in step S11 with the freezing depth of the soil base layer, and repeating steps S11 to S15; if yes, switching to step S16; S16. Calculate the amount of soil base frost heave based on the freezing depth of the soil base and the average frost heave rate of the soil; S17, judging whether the frost heave amount of the soil foundation is less than the allowable frost heave height of the pavement, and outputting the judgment result.

[0006] Preferably, the comprehensive thermal property coefficient is calculated based on the thickness and thermal property coefficient of each layer, and the calculation formula is as follows:

[0007] in, h i The thickness of each layer of the road surface from top to bottom; a i is the thermal physical coefficient of the corresponding layer structure material.

[0008] Preferably, the maximum freezing depth of the road surface is calculated based on the comprehensive thermal physical property coefficient, the preset roadbed humidity coefficient, the preset roadbed cross-sectional form coefficient and the earth's standard freezing depth, and the calculation formula is as follows:

[0009] in, Z max is the maximum freezing depth of the pavement; Z d Standard freezing depth for the earth; a is the comprehensive thermal physical property coefficient; b To preset the roadbed moisture coefficient; c It is the preset roadbed section form coefficient.

[0010] Preferably, the thickness of the pavement structure layer is calculated according to the thickness of each layer in the pavement structure layer, and the calculation formula is as follows:

[0011] in, h i is the thickness of each layer of the pavement structure from top to bottom; H ​​is the thickness of the pavement structure layer.

[0012] Preferably, the freezing depth of the soil base layer is calculated according to the maximum freezing depth of the pavement and the thickness of the pavement structure layer, and the calculation formula is as follows:

[0013] Among them, h 土 is the freezing depth of the soil base.

[0014] Preferably, the frost heave amount of the soil base is calculated according to the freezing depth of the soil base and the average frost heave rate of the soil, and the calculation formula is as follows:

[0015] Where h is the frost heave of the soil foundation, η is the average frost heave rate of soil, without considering the influence of pavement structure load.

[0016] According to a second aspect of an embodiment of the present invention, there is provided a device for determining the total thickness of a pavement structure based on frost heave, comprising: A main controller, and a memory connected to the main controller; The memory stores program instructions; The main controller is used to execute program instructions stored in the memory to perform any of the above methods.

[0017] The technical solution provided by the embodiments of the present invention may have the following beneficial effects: It is understandable that the technical solution shown in the present invention can obtain the thickness and thermophysical coefficient of each layer of the pavement, the thickness of the soil base is the assumed freezing thickness, and the comprehensive thermophysical coefficient is calculated; then the maximum freezing depth of the pavement is calculated; the thickness of the pavement structure layer is calculated; the freezing depth of the soil base is calculated; if the freezing depth of the soil base is not equal to the assumed freezing thickness, the assumed freezing thickness of the soil base is replaced by the freezing depth of the soil base, and the execution is repeated; according to the freezing depth of the soil base and the average freezing heave rate of the soil, the freezing heave of the soil base is calculated; it is judged whether the freezing heave of the soil base is less than the allowable freezing heave height of the pavement, and the judgment result is output. It is understandable that the technical solution shown in the present invention is suitable for quantitative determination of the thickness of the structural layer of cement concrete pavements and asphalt concrete pavements of airports and highways, and fills the gap in the quantitative calculation and determination of the thickness of the total structural layer of the pavement.

[0018] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0020] Figure 1 is a schematic diagram of steps of a method for determining the total thickness of a pavement structure based on frost heave according to an exemplary embodiment; Figure 2 is a schematic diagram of a road structure according to an exemplary embodiment. DETAILED DESCRIPTION

[0021] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are merely examples of devices and methods consistent with some aspects of the present invention as detailed in the appended claims.

[0022] In one embodiment, Figure 1 is a schematic diagram of the steps of a method for determining the total thickness of a pavement structure based on frost heave according to an exemplary embodiment, see Figure 1 , a method for determining the total thickness of a pavement structure based on frost heave is provided, comprising: Step S11, obtaining the thickness and thermophysical coefficient of each layer in the pavement structure layer, obtaining the assumed freezing thickness and thermophysical coefficient of the soil base layer, and calculating the comprehensive thermophysical coefficient based on the thickness and thermophysical coefficient of each layer.

[0023] In actual practice, the road is divided into a pavement structure layer and a soil base layer, and the pavement structure layer is composed of a surface layer, a base layer and a cushion layer, see Figure 2 Obtain the thickness and thermophysical coefficient of each layer of the surface layer, base layer and cushion layer, obtain the assumed freezing thickness of the soil base layer, which is the initial value, and obtain the thermophysical coefficient of the soil base layer. Based on the above data, the comprehensive thermophysical coefficient can be calculated.

[0024] It should be noted that the comprehensive thermal physical coefficient is calculated as follows:

[0025] in, h i The thickness of each layer of the road surface from top to bottom; a i is the thermal physical coefficient of the corresponding layer structure material. In the above formula, when i When it is equal to 4, it is the soil base layer, and the thickness of the soil base layer is the assumed freezing thickness.

[0026] The comprehensive thermal physical property coefficient is the weighted average value of the thermal physical property coefficients of each layer of materials within the freezing depth range of the earth.

[0027] Step S12, calculating the maximum freezing depth of the road surface according to the comprehensive thermal physical property coefficient, the preset roadbed humidity coefficient, the preset roadbed cross-sectional form coefficient and the earth's standard freezing depth.

[0028] It should be noted that the maximum freezing depth of the pavement can be calculated using the following formula:

[0029] in, Z max is the maximum freezing depth of the pavement; Z d Standard freezing depth for the earth; a is the comprehensive thermal physical property coefficient; b To preset the roadbed moisture coefficient; c It is the preset roadbed section form coefficient.

[0030] It can be understood that the maximum freezing depth of the road surface can be calculated through this calculation formula.

[0031] Step S13: Calculate the thickness of the pavement structure layer according to the thickness of each layer in the pavement structure layer.

[0032] It should be noted that the thickness of the pavement structure layer is calculated using the following formula:

[0033] in, h i is the thickness of each layer of the pavement structure layer from top to bottom, and the pavement structure layers from top to bottom are the surface layer, the base layer and the cushion layer; H is the thickness of the pavement structure layer. In addition, the number of pavement structure layers can be adjusted according to specific actual conditions.

[0034] Step S14: Calculate the freezing depth of the soil base layer according to the maximum freezing depth of the pavement and the thickness of the pavement structure layer.

[0035] It should be noted that the freezing depth of the soil base is calculated using the following formula:

[0036] Among them, h 土 is the freezing depth of the soil base.

[0037] Step S15, determine whether the freezing depth of the soil base layer is equal to the assumed freezing thickness. If not, replace the assumed freezing thickness of the soil base layer in step S11 with the freezing depth of the soil base layer, and repeat steps S11 to S15; if yes, go to step S16.

[0038] For example, if the initial assumed freezing thickness is 0.15 meters and the calculated freezing depth of the soil base layer is 0.1 meters, the assumed freezing thickness is replaced with 0.1 meters, and steps S11 to S15 are re-executed until the final freezing depth of the soil base layer is equal to the assumed freezing thickness. For example, if the assumed freezing thickness is 0.15 meters and the calculated freezing depth of the soil base layer is 0.15 meters, the repeated calculation is stopped and step S16 is executed.

[0039] Step S16: Calculate the frost heave amount of the soil base according to the freezing depth of the soil base and the average frost heave rate of the soil.

[0040] It should be noted that the calculation formula for calculating the frost heave of the soil foundation is as follows:

[0041] Where h is the frost heave of the soil foundation, η is the average frost heave rate of soil.

[0042] Step S17, determine whether the frost heave amount of the soil base is less than the allowable frost heave height of the pavement, and output the determination result.

[0043]

[0044] The allowable frost heave height of the pavement is specified in the specifications.

[0045] Taking a specific example, assuming that the road surface structure consists of four layers, namely cement surface layer, cement crushed stone layer, cement stabilized soil layer, and graded crushed stone layer, the thickness of the cement surface layer is 0.22m, and the thermal physical coefficient is 1.4; the thickness of the cement crushed stone layer is 0.25m, and the thermal physical coefficient is 1.4; the thickness of the cement stabilized soil layer is 0.38m, and the thermal physical coefficient is 1.35; the thickness of the graded crushed stone layer is 0.15m, and the thermal physical coefficient is 1.45.

[0046] The assumed freezing depth of the soil base under the pavement structure layer is 0.15m, and its thermal physical coefficient is 1.05.

[0047] Through the above data, the comprehensive thermal physical property coefficient can be calculated a :

[0048] Calculate the maximum freezing depth of the pavement Z max :

[0049] Calculate the pavement structure layer thickness H:

[0050] Calculate the freezing depth of the soil base below the pavement structure layer:

[0051] It can be seen that the calculated freezing depth of the soil base is consistent with the assumed value. Then, steps S16 to S17 are executed to determine whether the frost heave of the soil base is less than the allowable frost heave height of the pavement.

[0052] It is understandable that the technical solution shown in this embodiment can obtain the thickness and thermophysical coefficient of each layer of the pavement, the thickness of the soil base is the assumed freezing thickness, and the comprehensive thermophysical coefficient is calculated; then the maximum freezing depth of the pavement is calculated; the thickness of the pavement structure layer is calculated; the freezing depth of the soil base is calculated; if the freezing depth of the soil base is not equal to the assumed freezing thickness, the assumed freezing thickness of the soil base is replaced with the freezing depth of the soil base, and the execution is repeated; according to the freezing depth of the soil base and the average freezing heave rate of the soil, the freezing heave of the soil base is calculated; it is judged whether the freezing heave of the soil base is less than the allowable freezing heave height of the pavement, and the judgment result is output. It is understandable that the technical solution shown in this embodiment is applicable to the quantitative determination of the thickness of the structural layer of cement concrete pavements and asphalt concrete pavements of airports and highways, and fills the gap in the quantitative calculation and determination of the thickness of the total structural layer of the pavement.

[0053] According to a second aspect of an embodiment of the present invention, there is provided a device for determining the total thickness of a pavement structure based on frost heave, comprising: A main controller, and a memory connected to the main controller; The memory stores program instructions; The main controller is used to execute program instructions stored in the memory to perform any of the above methods.

[0054] It can be understood that the same or similar parts of the above embodiments can be referenced to each other, and the contents not described in detail in some embodiments can refer to the same or similar contents in other embodiments.

[0055] It should be noted that, in the description of the present invention, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, in the description of the present invention, unless otherwise specified, the meaning of "plurality" refers to at least two.

[0056] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code that includes one or more executable instructions for implementing the steps of a specific logical function or process, and the scope of the preferred embodiments of the present invention includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by those skilled in the art to which the embodiments of the present invention belong.

[0057] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0058] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0059] In addition, each functional unit in each embodiment of the present invention may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0060] The storage medium mentioned above can be a read-only memory, a magnetic disk or an optical disk, etc.

[0061] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0062] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A method for determining the total thickness of a pavement structure based on frost heave, characterized in that: include: S11, obtaining the thickness and thermophysical coefficient of each layer in the pavement structure layer, obtaining the assumed freezing thickness and thermophysical coefficient of the soil base layer, and calculating the comprehensive thermophysical coefficient according to the thickness and thermophysical coefficient of each layer; S12, calculating the maximum freezing depth of the road surface according to the comprehensive thermal physical property coefficient, the preset roadbed humidity coefficient, the preset roadbed cross-sectional form coefficient and the earth standard freezing depth; S13, calculating the thickness of the pavement structure layer according to the thickness of each layer in the pavement structure layer; S14, calculating the freezing depth of the soil base layer according to the maximum freezing depth of the road surface and the thickness of the road surface structure layer; S15, judging whether the freezing depth of the soil base layer is equal to the assumed freezing thickness; if not, replacing the assumed freezing thickness of the soil base layer in step S11 with the freezing depth of the soil base layer, and repeating steps S11 to S15; if yes, switching to step S16; S16. Calculate the amount of soil base frost heave based on the freezing depth of the soil base and the average frost heave rate of the soil; S17, judging whether the frost heave amount of the soil foundation is less than the allowable frost heave height of the pavement, and outputting the judgment result.

2. The method according to claim 1, characterized in that The comprehensive thermal property coefficient is calculated based on the thickness and thermal property coefficient of each layer, and the calculation formula is as follows: in, h i The thickness of each layer of the road surface from top to bottom; a i is the thermal physical coefficient of the corresponding layer structure material.

3. The method according to claim 2, characterized in that The maximum freezing depth of the road surface is calculated based on the comprehensive thermal physical property coefficient, the preset roadbed humidity coefficient, the preset roadbed cross-sectional form coefficient and the earth's standard freezing depth. The calculation formula is as follows: in, Z max is the maximum freezing depth of the pavement; Z d is the standard freezing depth of the earth; a is the comprehensive thermal physical property coefficient; b To preset the roadbed moisture coefficient; c It is the preset roadbed section form coefficient.

4. The method according to claim 3, characterized in that The thickness of the pavement structure layer is calculated according to the thickness of each layer in the pavement structure layer, and the calculation formula is as follows: in, h i is the thickness of each layer of the pavement structure from top to bottom; H ​​is the thickness of the pavement structure layer.

5. The method according to claim 4, characterized in that The freezing depth of the soil base layer is calculated according to the maximum freezing depth of the pavement and the thickness of the pavement structure layer. The calculation formula is as follows: Among them, h 土 is the freezing depth of the soil base.

6. The method according to claim 5, characterized in that According to the freezing depth of the soil base and the average frost heave rate of the soil, the frost heave amount of the soil base is calculated. The calculation formula is as follows: Where h is the frost heave of the soil foundation, η is the average frost heave rate of soil.

7. A device for determining the total thickness of a pavement structure based on frost heave, characterized in that: include: A main controller, and a memory connected to the main controller; The memory stores program instructions; The main controller is used to execute program instructions stored in the memory and execute the method according to any one of claims 1 to 6.

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