Half-excavated and half-filled broken line type composite roadbed in frozen soil area

Abstract

The utility model relates to the technical field of roads, in particular to a half-excavation and half-filling type fold line type composite roadbed in a frozen soil area, which comprises a composite roadbed, a fold line type ventilation pipe is arranged at a ramp of the composite roadbed, a gravel layer is arranged below the fold line type ventilation pipe, and a soil filling layer is arranged above the fold line type ventilation pipe. Wherein an air collecting opening is formed in the lower end portion of the composite roadbed, an air outlet is formed in the upper end of the composite roadbed, and at least two air outlet holes are formed in the position, close to the air outlet, of the fold-line-shaped ventilation pipe. For a steep slope high-temperature frozen soil road section with a larger gradient and the risk of sliding along an inclined freeze-thaw interface due to the fact that only a single slope direction exists, through the cooperation of the fold-line-shaped ventilation pipe and the composite roadbed, the hydrothermal change rule of the steep slope frozen soil roadbed is researched in a targeted mode, and the change condition of a roadbed temperature field is quantitatively analyzed.

Description

TECHNICAL FIELD

[0001] The utility model relates to road technical field, especially relate to a frozen soil area half -dig half -fill formula fold line type composite roadbed. BACKGROUND

[0002] In the high mountain area and high and cold mountainous area of our country, due to the existence of large area of permafrost for many years, the research on the thermal stability of frozen soil is also more important, and it is known from the existing research that the main influencing factors of frozen soil roadbed stability are the temperature and moisture content of soil, due to natural environmental factors, the temperature field distribution of steep slope frozen soil roadbed is geometrically asymmetric and asymmetric to slope direction. The construction of roadbed at this place causes the significant change of heat exchange conditions and water and heat transport process between permafrost and external environment, and the asymmetric distribution of roadbed temperature field, local aggregation of water, water migration in freezing and thawing process cause uneven frost heaving and thawing settlement of roadbed, road landslide and other serious diseases. Therefore, it has important practical significance to take corresponding improvement measures for how to prevent and treat the frost heaving, thawing settlement and other hazards of permafrost in high mountain area.

[0003] At present, engineering construction mainly adopts gravel roadbed and ventilation pipeline and combines mechanical support such as anti-slide pile or retaining wall, and good effect is obtained, but in the steeper and higher temperature frozen soil section of high and cold mountainous area road engineering in Xinjiang, the roadbed is mostly designed in half-cut type, and only has single slope direction, and the factors such as large rainfall and thick snow in winter cause the serious deficiency of roadbed and slope stability after excavation, and even there is the risk of sliding along the inclined freezing and thawing interface. UTILITY MODEL CONTENT

[0004] (I) technical problem solved

[0005] In view of the defects of the prior art, the utility model provides a frozen soil area half -dig half -fill formula fold line type composite roadbed, and solves the technical problem that at present engineering construction mainly adopts gravel roadbed and ventilation pipeline and combines mechanical support such as anti-slide pile or retaining wall, and good effect is obtained, but in the steeper and higher temperature frozen soil section of high and cold mountainous area road engineering in Xinjiang, the roadbed is mostly designed in half-cut type, and only has single slope direction, and the factors such as large rainfall and thick snow in winter cause the serious deficiency of roadbed and slope stability after excavation, and even there is the risk of sliding along the inclined freezing and thawing interface.

[0006] (II) technical scheme

[0007] To realize the above object, the utility model realizes by the following technical scheme:

[0008] The utility model provides a kind of frozen soil area semi-excavated semi-filled type broken line composite roadbed, including composite roadbed, broken line shape ventilation pipe is provided at the ramp of the composite roadbed, broken line shape ventilation pipe is provided with gravel layer below, broken line shape ventilation pipe is provided with fill layer above;Wherein, the lower end of the composite roadbed is provided with air inlet, the upper end of the composite roadbed is provided with air outlet, at least two air outlets are opened in broken line shape ventilation pipe close to air outlet, and there is inclined angle between each air outlet and broken line shape ventilation pipe.

[0009] Preferably: the shape of the cross section of the broken line shape ventilation pipe is broken line shape;Wherein, the broken line shape ventilation pipe is closely combined with the surface of composite roadbed, and the gravel layer is located between fill layer and broken line shape ventilation pipe.

[0010] Preferably: the top of the upper end of the broken line shape ventilation pipe is fixedly installed with water-proof sealing cover, and the angles of air outlet openings opened in the left and right sides of the broken line shape ventilation pipe are opposite.

[0011] (Three) beneficial effects

[0012] By setting broken line shape ventilation pipe on composite roadbed, the risk of sliding along inclined freezing and thawing interface in high and cold mountainous area road engineering, facing greater slope of steep slope high temperature frozen soil section, and only single slope direction is overcome, and the cooperation of the broken line shape ventilation pipe and the composite roadbed has the targeted research steep slope frozen soil roadbed water and heat variation law, quantitative analysis roadbed temperature field change. BRIEF DESCRIPTION OF DRAWINGS

[0013] The above description is only a summary of the technical scheme of the utility model, in order to more clearly understand the technical means of the utility model, and can be implemented according to the content of the specification, as follows the preferred embodiments of the utility model are described in detail with the help of drawings.

[0014] Figure 1 It is the structure diagram of the utility model broken line shape ventilation pipe composite roadbed;

[0015] Figure 2 It is the structure diagram of the utility model air outlet combination.

[0016] Legend: 1, composite roadbed;11, gravel layer;12, fill layer;13, broken line shape ventilation pipe;14, air inlet;15, air outlet;16, water-proof sealing cover;17, air outlet. DETAILED DESCRIPTION

[0017] The technical scheme in the embodiment of the application effectively solves the technical problem that the current engineering construction mainly adopts gravel roadbed and ventilation pipeline and simultaneously combines mechanical support such as anti-slide pile or retaining wall, achieves good effect, but the road engineering in the high-cold mountainous area of Xinjiang has the risk of sliding along the inclined freezing and thawing interface due to the factors such as large rainfall, thick snow in winter and the like, and the stability of the roadbed and the slope after excavation is seriously insufficient.

[0018] As Figure 1 and Figure 2 shown, the technical scheme in the embodiment of the application effectively solves the technical problem that the current engineering construction mainly adopts gravel roadbed and ventilation pipeline and simultaneously combines mechanical support such as anti-slide pile or retaining wall, achieves good effect, but the road engineering in the high-cold mountainous area of Xinjiang has the risk of sliding along the inclined freezing and thawing interface due to the factors such as large rainfall, thick snow in winter and the like, and the stability of the roadbed and the slope after excavation is seriously insufficient, and the general idea is as follows:

[0019] In view of the problems in the prior art, the utility model provides a kind of frozen soil area half-dug half-filled type broken line composite roadbed, including composite roadbed 1, the ramp of composite roadbed 1 is provided with broken line ventilation pipe 13, the lower portion of broken line ventilation pipe 13 is provided with gravel layer 11, and the upper portion of broken line ventilation pipe 13 is provided with fill layer 12;Wherein, the lower end of composite roadbed 1 is provided with air inlet 14, and the upper end of composite roadbed 1 is provided with air outlet 15;Broken line ventilation pipe 13 is provided with at least two air outlets 17 close to air outlet, and each air outlet 17 and broken line ventilation pipe 13 have inclination angle.

[0020] The shape of the cross section of broken line ventilation pipe 13 is broken line;Wherein, broken line ventilation pipe 13 is closely combined with the surface of composite roadbed 1, gravel layer 11 is located between fill layer 12 and broken line ventilation pipe 13, and water-proof sealing cover 16 is fixedly installed on the top of the upper end of broken line ventilation pipe 13, and the angles of air outlets 17 opened on the left and right sides of broken line ventilation pipe 13 are opposite.

[0021] Working principle:

[0022] First, in order to achieve the thermal stability of permafrost regions, the broken line-shaped ventilation pipe 13 should be closely fitted to the composite subgrade 1. When the broken line-shaped ventilation pipe 13 is installed, the position of the broken line-shaped ventilation pipe 13 should be measured in time and the broken line-shaped ventilation pipe 13 is laid in the trench according to the design. The broken line-shaped ventilation pipe 13 can be compacted by using a flat plate vibrator. The pipe diameter, laying spacing, buried height of the broken line-shaped ventilation pipe 13 and the environmental wind speed have a greater influence on the cooling effect of the composite subgrade 1. From the analysis of the convective heat transfer process, the forced convection intensity in the broken line-shaped ventilation pipe 13 is greater than the natural convection. When the viscous lag layer and the pipe wall heat transfer are not considered, the wind speed mainly affects the wind speed. With the increase of the pipe diameter of the broken line-shaped ventilation pipe 13, the wind speed in the pipe increases in a parabolic manner. The extension length of the broken line-shaped ventilation pipe 13 has a smaller influence on the wind speed in the pipe, but this influence gradually increases with the increase of the environmental wind speed. The wind speed in the pipe increases linearly with the increase of the buried height of the ventilation pipe. Therefore, the pipe diameter, buried depth and laying spacing of the broken line-shaped ventilation pipe 13 can be reasonably selected and manufactured according to the actual site survey.

[0023] The second step mainly includes the air inlet 14 below the composite subgrade 1, which can promote the air to enter the broken line-shaped ventilation pipe 13 and take away the heat of the surrounding soil. It also includes the air outlet 15 above the composite subgrade 1, the waterproof sealing cover 16 at the air outlet 15 and the air outlet hole 17 with a certain inclination angle to the horizontal direction arranged below the waterproof sealing cover 16. The gravel layer 11 and the filling layer 12 are arranged above and below the broken line-shaped ventilation pipe 13 under the composite subgrade 1, so as to improve the cooling efficiency of the frozen soil subgrade.

[0024] Finally, it should be pointed out that: obviously, the above examples are only examples for clearly illustrating the utility model, and are not limited to the implementation mode. For ordinary skilled persons in the art, other different forms of changes or variations can be made on the basis of the above description. Here, it is not necessary and impossible to enumerate all the implementation modes. The obvious changes or variations derived therefrom are still within the protection scope of the utility model.

Claims

1. A semi-cut-and-fill folded line type composite embankment in a frozen ground area, comprising a composite embankment (1), characterized in that, The composite roadbed (1) is provided with a zigzag ventilation pipe (13) at the slope thereof, the zigzag ventilation pipe (13) is provided with a gravel layer (11) below, and the zigzag ventilation pipe (13) is provided with a filling layer (12) above. The lower end of the composite roadbed (1) is provided with an air inlet (14), the upper end of the composite roadbed (1) is provided with an air outlet (15), the zigzag ventilation pipe (13) is provided with at least two air outlet holes (17) near the air outlet, and each air outlet hole (17) has an inclination angle with the zigzag ventilation pipe (13).

2. The folded line type composite subgrade of semi-cut and semi-fill in permafrost region according to claim 1, characterized in that, The zigzag ventilation pipe (13) has a zigzag cross section. The zigzag ventilation pipe (13) is closely attached to the surface of the composite roadbed (1).

3. The folded line type composite subgrade of semi-trench and semi-fill in permafrost regions according to claim 2, characterized in that, The gravel layer (11) is located between the filling layer (12) and the zigzag ventilation pipe (13).

4. The folded line type composite subgrade of semi-trench and semi-fill in permafrost regions according to claim 3, characterized in that, A waterproof sealing cover (16) is fixedly installed on the top of the upper end of the zigzag ventilation pipe (13).

5. The folded line type composite subgrade of semi-trench and semi-fill in permafrost regions according to claim 1, wherein, The angles of the air outlet holes (17) provided on the left and right sides of the zigzag ventilation pipe (13) are opposite.

Images