A highway subgrade structure using wrapped red mud as subgrade filler and a construction method thereof

Abstract

The present invention discloses a highway roadbed structure using wrapped red mud (including micro-treated red mud) as roadbed filler and a construction method thereof. The structure comprises, from bottom to top, a foundation adjustment layer, a liquid leakage prevention layer, a liquid permeation layer, a red mud filling layer and a liquid permeation layer arranged on a foundation, wherein the red mud filling layer is wrapped by the liquid leakage prevention layer, a permeation layer is arranged between the bottom of the red mud filling layer and the corresponding liquid leakage prevention layer, the permeation layer is provided with a seepage drainage pipe, and the seepage of the red mud filling layer is guided out to a collection system through the permeation layer along the seepage drainage pipe; the land occupied by red mud stacking is saved, the impact of red mud on the environment is reduced, a good storage place is provided for the secondary development of red mud, a large amount of red mud is utilized, its adverse factors are controlled, and rare earth and rare metals in the red mud are also stored in the roadbed, thereby greatly reducing the cost of stacking and maintenance, and achieving the purpose of energy saving and consumption reduction and material saving.

Description

Technical Field

[0001] The invention relates to a roadbed structure, in particular to a highway roadbed structure using wrapped red mud as roadbed filler and a construction method thereof. Background Art

[0002] Red mud is a solid material with extremely fine particles, strong alkalinity, rich in rare earth and rare metals, and certain radioactivity produced in the process of producing alumina from bauxite. It belongs to Class II general industrial solid waste and is directly used in roadbed filling, which has certain harmful effects on the environment, soil, and groundwater. The land occupation index and volume of red mud accumulation have reached the environmental bearing limit, and the direct or indirect utilization is very limited. The phenomenon of environmental pollution has shown irreversible phenomenon. At present, the cost of extracting rare elements is high and the technology is immature. Summary of the invention

[0003] In view of this, the purpose of the present invention is to overcome the defects in the existing application technology, provide a highway roadbed structure with wrapped red mud as roadbed filler and its construction method, save the area occupied by red mud stacking, reduce the impact of red mud on the environment, provide a good reserve place for the secondary development of red mud, utilize a large amount of red mud, control its adverse factors, and at the same time store the rare earth and rare metals in the red mud in the roadbed, greatly reduce the cost of stacking and maintenance, and achieve the purpose of energy saving and consumption reduction, and saving materials.

[0004] The present invention discloses a highway subgrade structure with wrapped red mud as subgrade filler, which comprises, from top to bottom, a foundation adjustment layer arranged on the foundation, a liquid leakage prevention layer, a liquid permeation layer, a red mud (or modified red mud) filling layer and a liquid permeation layer, wherein the red mud filling layer is wrapped with the liquid leakage prevention layer, a permeable layer is arranged between the bottom of the red mud filling layer and the corresponding liquid leakage prevention layer, the permeable layer is provided with a seepage drainage pipe, the seepage of the red mud filling layer is led out to a collection system through the permeable layer along the seepage drainage pipe, drainage slopes are arranged longitudinally and transversely on the top surface of the foundation adjustment layer, the seepage drainage pipe is arranged in the permeable layer at the foot of the seepage collection slope, and the red mud seepage flows through the seepage drainage pipe along the transverse slope.

[0005] Furthermore, it also includes a slope protection layer arranged along the slope of the embankment, wherein the slope protection layer is arranged on the liquid leakage prevention layer located on the slope;

[0006] Furthermore, the invention also includes seepage drainage pipes evenly distributed at equal intervals along the embankment slope at the seepage permeable layer located at the bottom of the roadbed;

[0007] Furthermore, the invention also includes a seepage collection system arranged corresponding to the seepage drainage pipe, and the seepage from the red mud filler layer enters the seepage collection system through the seepage drainage pipe;

[0008] Furthermore, the seepage collection system is a ditch, trough, pool, barrel-shaped structure container, etc. arranged along one side of the embankment slope;

[0009] Furthermore, the liquid-permeable layer is a crushed stone material or a composite three-dimensional product with water permeability.

[0010] The invention discloses a construction method of a highway subgrade structure using wrapped red mud as subgrade filler, comprising the following steps:

[0011] The red mud filled roadbed centerline and cross-section ground line are actually measured, and the ground humus soil is cleaned to implement the foundation adjustment layer with a certain slope;

[0012] Implementing a liquid seepage prevention layer on the top surface of the foundation adjustment layer, and laying a seepage drainage pipe on the liquid seepage prevention layer;

[0013] Implement liquid filtering measures at the inlet end of the seepage drainage pipe, then implement the seepage permeation layer and implement the seepage collection system;

[0014] Treat the end of the liquid-proof layer and implement the side liquid-proof layer to ensure that the liquid in the permeable layer in the end area does not seep out of the side liquid-proof layer and the external water does not seep into the permeable layer;

[0015] Implement red mud road base filling and slope anti-liquid leakage layer;

[0016] Implement roadbed slope protection and top liquid seepage prevention layer;

[0017] Lay the base layer and pavement structure layer.

[0018] Furthermore, in step a, if the ground line in the cross section is a relatively gentle one-way slope, the foundation adjustment layer is directly implemented, and drainage slopes are set on the top surface of the foundation adjustment layer along the longitudinal and transverse directions according to the terrain to ensure that after the anti-leakage layer is laid, the seepage on its top surface flows to the seepage drainage pipe.

[0019] Furthermore, in step a, if the ground line of the cross section is steep, the foundation can be processed into a step manner, and then a foundation adjustment layer is implemented, and the top surface of the foundation adjustment layer is a one-way slope.

[0020] Furthermore, in step a, if the cross-sectional ground line is a gentle two-way slope and the roadbed is relatively wide, the foundation adjustment layer is directly implemented, and the top surface of the foundation adjustment layer is a two-way slope; if the cross-sectional ground line is a steep two-way slope and the roadbed is relatively wide, the foundation can be processed into a stepped manner, and then the foundation adjustment layer is implemented, and the top surface of the foundation adjustment layer is a two-way slope.

[0021] The beneficial effects of the present invention are as follows: the present invention discloses a highway subgrade structure and a construction method thereof with wrapped red mud as subgrade filler, wherein the red mud is wrapped by a liquid-proof leakage-proof layer to prevent atmospheric rainwater, road surface water, and foundation capillary water from entering the red mud body, so as to prevent the red mud from seeping into the outside of the liquid-proof leakage-proof layer; through the permeable layer under the red mud body, on the one hand, it is ensured that there is no water accumulation at the bottom of the red mud, and on the other hand, the red mud seepage is collected and collected by the permeable layer and the bottom liquid-proof leakage-proof layer, and enters the collection device. The seepage in the collection device is treated or recycled to avoid the strong alkaline solution, heavy metals, and radioactive substances in the seepage from entering the soil or river to pollute the environment. By adopting this technology, the filling subgrade can save the area occupied by red mud stacking, reduce the impact on the environment, and provide a good reserve place for the secondary development of red mud. At the same time, a large amount of red mud can be utilized, its adverse factors can be controlled, and the rare earths and rare metals in the red mud can be stored in the subgrade, which greatly reduces the cost of stacking and maintenance, saves energy and reduces consumption, and saves materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0023] Figure 1 It is a structural schematic diagram of the present invention; DETAILED DESCRIPTION

[0024] Figure 1: is a structural schematic diagram of the invention. The highway subgrade structure with wrapped red mud as subgrade filler in this embodiment comprises, from bottom to top, a foundation adjustment layer 2 with a certain slope arranged on a foundation 1, a red mud filler layer 3, a base layer 4 and a pavement layer. The red mud filler layer 3 is wrapped with a liquid-proof leakage layer 5, a permeable layer 6 is arranged between the bottom of the red mud filler layer 3 and the corresponding liquid-proof leakage layer 5, and the liquid-proof leakage layer 5 corresponding to the permeable layer 6 is provided with a seepage drainage pipe 7, and the seepage of the red mud filler layer 3 is discharged centrally along the seepage drainage pipe 7 through the permeable layer 6; the red mud is wrapped by the liquid-proof leakage layer 5 as a subgrade filler, and the load on the subgrade is transmitted to the foundation 1 through the wrapped red mud body. The foundation adjustment layer 2 generally has a certain slope, and the anti-leakage layer 5 adopts the anti-leakage material in the prior art, such as geotextile and plastic with anti-leakage effect, etc., and the permeable layer 6 is below the red mud body. The anti-leakage layer 5 wraps the red mud body and the top layer as a whole (the red mud body and the permeable layer 6 are completely enclosed in the anti-leakage layer 5), and the anti-leakage layer 5 includes a bottom anti-leakage layer 5, a side anti-leakage layer 5 and a top anti-leakage layer 5 set corresponding to the roadbed. The seepage in the red mud filler wrapped by the anti-leakage layer 5 penetrates along the bottom of the red mud to reach the permeable layer 6, passes through the permeable layer 6, and is concentrated in the anti-leakage layer 5 above the foundation adjustment layer 2, and then is discharged through the seepage drainage pipes 7 evenly distributed in the permeation layer 6. Since the foundation adjustment layer 2 has a certain slope, the seepage drainage pipes 7 are set in the permeable layer 6 below the slope of the foundation adjustment layer 2, which is convenient for drainage. It is preferred to set a seepage drainage pipe 7 at the junction of the permeable layer 6 on the side of the roadbed cross section and the lower anti-liquid leakage layer 5, and the seepage drainage pipes 7 are distributed at equal intervals. In this way, the red mud is wrapped by the anti-liquid leakage layer 5 to prevent atmospheric rainwater, road water, and foundation capillary water from entering the red mud body, so as to prevent the seepage inside the red mud from penetrating into the anti-liquid leakage layer 5; by setting a permeable layer under the red mud body, on the one hand, it is ensured that there is no water accumulation at the bottom of the red mud, and on the other hand, the red mud seepage is collected by the permeable layer and the bottom anti-liquid leakage layer 5, and the rare earth and rare metals in the red mud exist in the roadbed.

[0025] In this embodiment, drainage slopes are arranged on the top surface of the foundation adjustment layer 2 in the longitudinal and transverse directions, and the seepage drainage pipe 7 is arranged corresponding to the foot of the drainage slope, and the red mud seepage flows through the seepage drainage pipe 7 along the drainage slope; if the cross-sectional ground line is a gentle one-way slope, the foundation adjustment layer 2 is directly implemented, and drainage slopes are arranged on the top surface of the foundation adjustment layer 2 in the longitudinal and transverse directions according to the terrain to ensure that the seepage on the top surface flows smoothly to the seepage drainage pipe 7 after the liquid-proof leakage layer 5 is laid, and no liquid accumulates; when the cross-sectional ground line is steep, the foundation 1 can be processed into a step-like manner, and then the foundation adjustment layer 2 is implemented, and the top surface of the foundation adjustment layer 2 is a one-way slope; if the cross-sectional ground line is a gentle two-way slope and the roadbed is fast and wide, the foundation adjustment layer 2 is directly implemented, and the top surface of the foundation adjustment layer 2 is a two-way slope; if the cross-sectional ground line is a steep two-way slope and the roadbed is fast and wide, the foundation 1 can be processed into a step-like manner, and then the foundation adjustment layer 2 is implemented, and the top surface of the foundation adjustment layer 2 is a two-way slope. A liquid seepage prevention layer 5 is implemented on the top surface of the foundation adjustment layer 2, and a seepage drainage pipe 7 is arranged on the liquid seepage prevention layer 5; if the top of the foundation adjustment layer 2 is a double-sided slope, a seepage drainage pipe 7 is also arranged on the other side.

[0026] In this embodiment, it also includes a slope protection layer 8 arranged along the embankment slope, and the slope protection layer 8 is arranged on the liquid leakage prevention layer 5 located on the slope; the slope surface protection, liquid leakage prevention layer 5, red mud layer, permeable layer, adjustment layer and collection device are jointly used as an embankment roadbed system, and the load on the roadbed is transmitted to the foundation 1 through the wrapped red mud body.

[0027] In this embodiment, the seepage drainage pipes 7 are evenly distributed on the permeable layer 6 located at the ground line at equal intervals along the embankment slope to improve the drainage effect.

[0028] In this embodiment, a seepage collection system 9 is also included, which is set corresponding to the seepage drainage pipe 7. The seepage of the red mud filler layer 3 enters the seepage collection system 9 through the seepage drainage pipe 7; the seepage collection system 9 is a ditch, groove, pool, or barrel-shaped structure container excavated along the ground line on one side of the embankment slope; the seepage entering the collection device is treated or recycled to prevent the strong alkaline liquid, heavy metals, and radioactive substances in the seepage from entering the soil or river to pollute the environment. The simplest seepage collection system 9 uses a ditch, groove or pool excavated on the foundation on the side of the embankment, and a barrel-shaped structure container is installed. The seepage enters the ditch, groove or pool, or barrel-shaped structure container along the seepage drainage pipe 7 for centralized collection.

[0029] In this embodiment, the permeable layer 6 is a permeable material such as crushed stone. Crushed stone is preferably used to infiltrate and filter the seepage of the red mud body. On the one hand, it ensures that there is no water accumulation at the bottom of the red mud. On the other hand, the red mud seepage is collected through the permeable layer 6 and the bottom liquid-proof leakage layer 5, and the rare earth and rare metals in the red mud are also stored in the roadbed.

[0030] A construction method of a highway roadbed structure using wrapped red mud as roadbed filler in this embodiment comprises the following steps:

[0031] The red mud filled roadbed centerline and cross-section ground line are actually measured, and the ground humus soil is cleaned to implement the foundation adjustment layer with a certain slope;

[0032] Implementing a liquid seepage prevention layer on the top surface of the foundation adjustment layer, and laying a seepage drainage pipe on the liquid seepage prevention layer;

[0033] Implement liquid filtering measures at the inlet end of the seepage drainage pipe, then implement the seepage permeation layer and implement the seepage collection system;

[0034] Treat the end of the liquid-proof layer and implement the side liquid-proof layer to ensure that the liquid in the permeable layer in the end area does not seep out of the side liquid-proof layer and the external water does not seep into the permeable layer;

[0035] Implement red mud road base filling and slope anti-liquid leakage layer;

[0036] Implement roadbed slope protection and top liquid seepage prevention layer;

[0037] Lay the base layer and pavement structure layer.

[0038] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A highway subgrade structure using wrapped red mud as subgrade filler, characterized in that: The invention comprises, from bottom to top, a foundation adjustment layer, a liquid seepage prevention layer, a liquid permeation layer and a red mud filling layer arranged on the foundation. The red mud filling layer is wrapped with the liquid seepage prevention layer. A liquid permeation layer is arranged between the bottom of the red mud filling layer and the corresponding liquid seepage prevention layer. The liquid permeation layer is provided with a seepage drainage pipe. A seepage drainage pipe is arranged at the junction of the liquid permeation layer on the side of the cross section of the roadbed and the liquid seepage prevention layer below. The seepage of the red mud filling layer is led out to the collection system along the seepage drainage pipe through the liquid permeation layer. Drainage slopes are arranged on the top surface of the foundation adjustment layer in the longitudinal and transverse directions, and the red mud seepage flows through the seepage drainage pipe along the transverse slope, and the seepage drainage pipe collects the seepage into the liquid permeation layer at the foot of the slope; the liquid leakage prevention layer seals the red mud filling layer and the permeable layer as a whole in the liquid leakage prevention layer; it also includes a slope protection layer arranged along the embankment slope, and the slope protection layer is arranged on the liquid leakage prevention layer located on the slope; the liquid permeation layer is a crushed stone material or a composite three-dimensional product with water permeability, and the liquid leakage prevention layer is a geotextile or plastic.

2. The highway subgrade structure using wrapped red mud as subgrade filler according to claim 1 is characterized in that: The seepage drainage pipes are evenly distributed at equal intervals along the embankment slope on the seepage permeable layer located at the bottom of the roadbed.

3. The highway subgrade structure using wrapped red mud as subgrade filler according to claim 1, characterized in that: The invention also comprises a seepage collection system arranged corresponding to the seepage drainage pipe, and the seepage from the red mud filler layer enters the seepage collection system through the seepage drainage pipe.

4. The highway subgrade structure using wrapped red mud as subgrade filler according to any one of claims 1 to 3, characterized in that: The seepage collection system is a trench, trough, pool, or barrel-shaped container arranged along one side of the embankment slope.

5. The construction method of a highway subgrade structure using wrapped red mud as subgrade filler according to claim 1, characterized in that: The following steps are involved: a. Actual measurement of red mud filled roadbed centerline and cross-section ground line, clean the ground humus soil and implement a foundation adjustment layer with a certain slope; b. Implementing a liquid-proof leakage-proof layer on the top surface of the base adjustment layer, and laying a seepage drainage pipe on the liquid-proof leakage-proof layer; c. Implement liquid filtering measures at the inlet end of the seepage drainage pipe, and then implement the liquid permeation layer and the collection system; d. Treat the end of the liquid-proof layer and implement the side liquid-proof layer to ensure that the liquid in the end area of ​​the permeable layer does not seep out of the side liquid-proof layer and the external water does not seep into the permeable layer; e. Implement red mud road base filling and slope anti-liquid leakage layer; f. Implement roadbed slope protection and top liquid leakage prevention layer; g. Laying the base layer and pavement structure layer.

6. The construction method of a highway subgrade structure using wrapped red mud as subgrade filler according to claim 5, characterized in that: In step a, if the ground line of the cross section is a gentle one-way slope, the foundation adjustment layer is directly implemented, and drainage slopes are set on the top surface of the foundation adjustment layer along the longitudinal and transverse directions according to the terrain to ensure that the seepage on its top surface flows to the seepage drainage pipe after the liquid-proof seepage-proof layer is laid.

7. The construction method of a highway subgrade structure using wrapped red mud as subgrade filler according to claim 5, characterized in that: In step a, if the ground line of the cross section is steep, the foundation is treated into a step manner, and then a foundation adjustment layer is implemented, and the top surface of the foundation adjustment layer is a one-way slope.

8. The construction method of a highway subgrade structure using wrapped red mud as subgrade filler according to claim 5, characterized in that: In step a, if the cross-sectional ground line is a gentle two-way slope and the roadbed is wide, the foundation adjustment layer is directly implemented, and the top surface of the foundation adjustment layer is a two-way slope; if the cross-sectional ground line is a steep two-way slope and the roadbed is wide, the foundation is treated into a step manner, and then the foundation adjustment layer is implemented, and the top surface of the foundation adjustment layer is a two-way slope.

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