Heat insulation geogrid for roadbed in permafrost region

Abstract

The utility model relates to a heat insulation geogrid for a roadbed in a permafrost region. The heat insulation geogrid comprises a first geogrid and a second geogrid, a sand cushion layer is paved between the first geogrid and the second geogrid; sand cushion layers are paved at the bottom of the first geogrid and the top of the second geogrid; the bottom of the first geogrid is formed by splicing a plurality of first cells; and the second geogrid is formed by splicing a plurality of second cells. The heat insulation projection surfaces of the two layers of geogrids cover the whole roadbed base, a sand cushion layer is laid on the second geogrid, roadbed heat insulation layer construction is completed, downward conduction of heat of an upper structure of a roadbed is reduced, it is guaranteed that the upper limit of frozen soil under the base does not severely decline, the stability of the filled roadbed is greatly improved, and the uneven settlement amount is reduced; and roadbed diseases are reduced.

Description

Technical Field

[0001] The utility model relates to a geogrid, in particular to a geogrid used for heat insulation of roadbed in permafrost areas and for strengthening roadbed stability, and is particularly suitable for roadbed construction areas with shallow upper buried depth of permafrost. Background Art

[0002] At present, the construction of highway and railway projects in my country has entered a new period. The construction quality standards are getting higher and higher, the construction area is getting wider and wider, and the construction of transportation infrastructure in high-altitude and cold plateau areas is gradually underway. However, due to the special climatic conditions in the plateau area, a special type of rock and soil is usually encountered during project construction - permafrost. The main cause of engineering diseases in permafrost areas is the melting of permafrost. The construction of engineering projects disturbs the frozen soil environment inside the original soil body. The melting of permafrost reduces the strength of the foundation soil, causing roadbed slippage, cracking and other diseases. Therefore, the design of highway and railway projects in permafrost areas follows the principle of filling rather than digging to reduce the disturbance to the original frozen soil environment. However, it is often inevitable to produce excavation sections, which disturb the foundation soil and cause the degradation of the permafrost upper limit. Therefore, it is necessary to take necessary measures to minimize the disturbance and reduce the downward conduction of heat absorbed by the upper structure of the roadbed to ensure the stability of the roadbed in later operations.

[0003] At present, the embankment filling in permafrost areas adopts the rubble air-cooled embankment to isolate the heat absorbed by the upper structure of the embankment from being conducted downwards, preventing it from further disturbing the lower frozen soil environment. However, due to the large pores of the rubble air-cooled embankment, while isolating the upper heat, the air circulation will bring the heat in the air into the embankment, causing the heat to be conducted downwards to the deep foundation soil, causing the frozen soil to melt and the foundation to become unstable. At the same time, the rubble base cannot provide tension, resulting in obvious manifestation of base diseases. In order to make up for the problem of traditional rubble air-cooled embankment conducting air heat and failing to provide horizontal connection force for the base, a thermal insulation geogrid was designed and invented. Utility Model Content

[0004] The purpose of the utility model is to solve the above-mentioned shortcomings and provide a heat-insulating geogrid for roadbed in permafrost areas, which can isolate the heat from the upper part of the roadbed from transferring downward, minimize the disturbance of frozen soil, provide horizontal connection force of the grid, and increase the overall stability of the roadbed.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] A thermal insulation geogrid for roadbed in permafrost areas comprises a first geogrid and a second geogrid; a sand cushion layer is spread between the first geogrid and the second geogrid; a sand cushion layer is spread at the bottom of the first geogrid and the top of the second geogrid; the bottom of the first geogrid is composed of a plurality of first cells spliced ​​together; and the second geogrid is composed of a plurality of second cells spliced ​​together.

[0007] Furthermore, the first unit cell has a first frame; a right-angled first heat insulation board is arranged in the first frame; the first heat insulation board is distributed at the four vertex corners inside the first frame; and prismatic spaces are formed between the four first heat insulation boards.

[0008] Furthermore, first horizontal buckles are provided on the outside of two sides of the first frame; first slots are provided on the inside of the other two sides of the first frame; and two adjacent first frames are horizontally connected via the first horizontal buckles and the first slots.

[0009] Furthermore, soil nails are provided at the bottom of the first heat insulation board; and the first heat insulation board is provided with an embedding groove that cooperates with the first clamping groove.

[0010] Furthermore, the second unit cell has a second frame; the second frame has a second heat insulation board inside; the second heat insulation board is prismatic; the second heat insulation board is arranged opposite to the prismatic space.

[0011] Furthermore, the second frame is also provided with a second horizontal buckle and a second slot; the second horizontal buckle and the second slot are distributed in the same manner as the first horizontal buckle and the first slot.

[0012] Furthermore, a right-angle space is formed between the second insulation board and the second frame; the right-angle space is arranged opposite to the first insulation board; the second slot is located in the right-angle space; and soil nails are arranged at the bottom of the second insulation board.

[0013] The utility model has the following beneficial effects: the geogrid needs to be paved in double layers. When in use, a layer of sand cushion is first paved on the base, and then the first geogrid is paved. The insulation area of ​​the first geogrid is 50%. After the first geogrid is paved, the second layer of sand cushion is paved, and then the second geogrid is paved. The insulation area of ​​the second geogrid is 50%. The insulation projection surface of the two layers of geogrids covers the entire roadbed base. A sand cushion layer is paved on the second geogrid to complete the construction of the roadbed insulation layer, reduce the downward conduction of heat from the upper structure of the roadbed, ensure that the upper limit of frozen soil under the base will not seriously decline, greatly improve the stability of the filled roadbed, reduce uneven settlement, and reduce the occurrence of roadbed diseases.

[0014] The beneficial effects of the utility model are to reduce the downward conduction of heat from the upper structure of the roadbed, protect the upper limit of the permafrost under the base, reduce the uneven settlement, increase the stability of the roadbed, and reduce the occurrence of roadbed diseases in permafrost areas. At the same time, the horizontally connected buckles and slots are used to connect adjacent cells to form the first geogrid or the second geogrid, so that the first geogrid or the second geogrid has horizontal connection force, thereby improving the overall stability of the roadbed. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the cross-sectional structure of the utility model.

[0016] Figure 2 It is a schematic diagram of the structure of the first geogrid and the second geogrid.

[0017] Figure 3 This is a schematic structural diagram of the first geogrid and the second geogrid in another orientation.

[0018] Figure 4 This is a schematic diagram of the structure of the first unit cell.

[0019] Figure 5 This is a schematic diagram of the structure of the first unit cell in another orientation.

[0020] Figure 6 This is a schematic diagram of the structure of the second unit cell.

[0021] Figure 7 This is a schematic diagram of the structure of the second unit cell in another orientation.

[0022] In the figure: 1 is the first geogrid, 2 is the second geogrid, 3 is the sand cushion layer, 4 is the first unit cell, 41 is the first skeleton, 42 is the first thermal insulation board, 43 is the first horizontal buckle, 44 is the first slot, 5 is the second unit cell, 51 is the second skeleton, 52 is the second thermal insulation board, 53 is the second horizontal buckle, 54 is the second slot, 6 is the soil nail, 7 is the upper limit of frozen soil, and 8 is the roadbed superstructure. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0024] The terms used herein, including technical and scientific terms, have the same meaning as those generally understood by those skilled in the art, unless the terms are defined differently. It should be understood that the terms defined in commonly used dictionaries have the same meaning as those in the prior art.

[0025] See also Figure 1-Figure 7

[0026] A thermal insulation geogrid for roadbed in permafrost areas, comprising a first geogrid 1 and a second geogrid 2; a sand cushion layer 3 is spread between the first geogrid 1 and the second geogrid 2; a sand cushion layer 3 is spread at the bottom of the first geogrid and the top of the second geogrid 2; the bottom of the first geogrid 1 is composed of a plurality of first cells 4 spliced ​​together; and the second geogrid 2 is composed of a plurality of second cells 5 spliced ​​together.

[0027] Furthermore, the first unit cell 4 has a first frame 41; a right-angled first heat insulation board 42 is arranged inside the first frame 41; the first heat insulation board 42 is distributed at the four top corners inside the first frame 41; and a prismatic space is formed between the four first heat insulation boards 42.

[0028] Specifically, first horizontal buckles 43 are disposed on the outside of both sides of the first frame 41 ; first slots 44 are disposed on the inside of the other two sides of the first frame 41 ; and two adjacent first frames 41 are horizontally connected via the first horizontal buckles 43 and the first slots 44 .

[0029] Furthermore, soil nails 6 are provided at the bottom of the first heat insulation board 42 ; and the first heat insulation board 42 is provided with an embedding groove that cooperates with the first clamping groove 44 .

[0030] Before the roadbed is filled, a layer of sand cushion 4 is spread on the base. After the paving and leveling, the first geogrid 1 is laid. After the first geogrid 1 is laid and compacted, another layer of sand cushion 4 is spread, and then the second geogrid 2 is laid. After compaction, another layer of sand cushion is spread on the second geogrid 2 to protect the upper structure 8 of the roadbed from being damaged during the paving. The first geogrid 1 and the second geogrid 2 are respectively composed of a plurality of first cells 4 and second cells 5. Each first cell 4 is composed of a first heat insulation board 42, a first skeleton 4 1. It is composed of a first horizontal buckle 43, a first slot 44 and a soil nail 6. The first insulation board 42 is connected to the first frame 41. The bottom of the first insulation board 42 is connected to the soil nail 6. The first insulation board 42 reduces the downward conduction of heat from the roadbed superstructure 1. When paving, the soil nail 6 is inserted into the sand cushion layer 4 to prevent the first cell 4 from slipping. The first frame 41 is connected with a first horizontal buckle 43 to connect each first cell 4. When paving, each first cell 4 is connected through the first horizontal buckle 43 and the first slot 44.

[0031] Furthermore, the second unit cell 5 has a second frame 51; the second frame 51 has a second heat insulation board 52; the second heat insulation board 52 is prismatic; and the second heat insulation board 52 is arranged opposite to the prismatic space.

[0032] Furthermore, the second frame 51 is also provided with a second horizontal buckle 53 and a second slot 54; the second horizontal buckle 53 and the second slot 54 are distributed in the same manner as the first horizontal buckle and the first slot.

[0033] The connection method of each second cell 5 in the second geogrid 2 is the same as the connection method of each first cell 4 in the first geogrid 1, so it will not be repeated. The first insulation board 42 and the second insulation board 52 on the first geogrid 1 and the second geogrid 2 form a complete plane, and the projection of the two layers of geogrid insulation boards covers the entire roadbed base. The reason for paving two layers of geogrids is, first, to meet the integrity between the roadbed superstructure and the foundation soil, so as not to completely isolate them and cause other diseases, and second, to increase the connection capacity and stability of the geogrid. The projection surface of the insulation board covers the entire roadbed base, which can reduce the heat absorbed by the roadbed superstructure and conduct downward, thereby reducing the decline of the permafrost upper limit 7, reducing the adverse geological disasters such as thawing and settlement caused by the change of the permafrost environment when the roadbed is built, and increasing the stability of the roadbed.

[0034] Furthermore, a right-angle space is formed between the second insulation board and the second frame; the right-angle space is arranged opposite to the first insulation board; the second slot is located in the right-angle space; and soil nails are arranged at the bottom of the second insulation board.

[0035] Finally, it should be noted that the above embodiments are only for illustrating the technical solution of the utility model rather than limiting it. Although the utility model is described in detail with reference to the preferred embodiments, ordinary technicians in the field should understand that the technical solution of the utility model can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the utility model, which should be included in the scope of the claims of the utility model.

Claims

1. A thermal insulation geogrid for roadbed in permafrost areas, characterized by: It comprises a first geogrid and a second geogrid; a sand cushion layer is spread between the first geogrid and the second geogrid; a sand cushion layer is spread at the bottom of the first geogrid and the top of the second geogrid; the bottom of the first geogrid is composed of a plurality of first cells; and the second geogrid is composed of a plurality of second cells.

2. The thermal insulation geogrid for roadbed in permafrost areas according to claim 1, characterized in that: The first unit cell has a first frame; a right-angled first heat insulation board is arranged in the first frame; the first heat insulation board is distributed at the four vertex corners inside the first frame; and a prismatic space is formed between the four first heat insulation boards.

3. The thermal insulation geogrid for roadbed in permafrost areas according to claim 2, characterized in that: First horizontal buckles are arranged outside the two sides of the first frame; first slots are arranged inside the other two sides of the first frame; and two adjacent first frames are horizontally connected through the first horizontal buckles and the first slots.

4. The thermal insulation geogrid for roadbed in permafrost areas according to claim 3, characterized in that: The bottom of the first heat insulation board is provided with soil nails; the first heat insulation board is provided with an embedding groove matched with the first clamping groove.

5. The thermal insulation geogrid for roadbed in permafrost areas according to claim 1 or 2, characterized in that: The second unit cell has a second frame; the second frame has a second heat insulation board inside; the second heat insulation board is prismatic; the second heat insulation board is arranged opposite to the prismatic space.

6. The thermal insulation geogrid for roadbed in permafrost areas according to claim 5, characterized in that: The second frame is also provided with a second horizontal buckle and a second slot; the second horizontal buckle and the second slot are distributed in the same manner as the first horizontal buckle and the first slot.

7. The thermal insulation geogrid for roadbed in permafrost areas according to claim 6, characterized in that: A right-angle space is formed between the second heat insulation board and the second frame; the right-angle space is arranged opposite to the first heat insulation board; the second slot is located in the right-angle space; soil nails are arranged at the bottom of the second heat insulation board.

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