Waterproof and drainage structure for railway yard roadbed in high-water-level salinized soil permafrost region
By setting up a lower drainage layer, an upper water-proof layer, and a rapid flow channel in the railway station subgrade in high-water-level saline-frozen soil areas, the problem of subgrade deformation caused by frost heave and thaw settlement was solved, and the stability and construction convenience of the subgrade were improved.
Patent Information
- Application Number
- CN202520292021.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-24
- Publication Date
- 2026-01-20
- Estimated Expiration
- 2035-02-24
AI Technical Summary
In high-water-level saline-fertile frozen soil areas, existing roadbed drainage and waterproofing measures are prone to cracking and deformation, making it difficult to adapt to the repeated effects of frost heave and thaw settlement, affecting the stability of the roadbed, and making maintenance difficult.
The structure employs a lower drainage layer, an upper waterproof layer, and a rapid flow channel. Through the combination of inclined slopes and specific materials, it achieves rapid drainage, prevents water infiltration, and enhances the stability of the roadbed.
It effectively prevents the impact of frost heave and thaw settlement on the roadbed, improves the stability of the roadbed, reduces the project cost, and the material has high safety and ease of construction, adapting to environmental changes in permafrost regions.
Smart Images
Figure CN223813660U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the technical field of railway station yard subgrade drainage, and particularly relates to a high-water-level saline soil frozen soil area railway station yard subgrade drainage structure. BACKGROUND
[0002] Many lines inevitably pass through frozen soil areas, which puts higher requirements on the stability of the subgrade of the line in the frozen soil area, and water is a key factor affecting the stability of the subgrade, so the waterproof and drainage engineering measures are crucial. In the high-water-level saline soil frozen soil area, due to the reciprocating action of the frost heaving and thawing of the foundation soil, the ordinary subgrade waterproof and drainage engineering measures commonly used in ordinary areas are prone to cracks and deformation, and at the same time, due to the influence of the highland working conditions, it is difficult to discover and maintain and repair in time, so water seeps into the soil along the deformation part or the crack of the drainage ditch, and greater deformation is generated again after the cold and warm seasons are replaced, and finally the drainage system is damaged and fails, thereby affecting the stability of the subgrade. Therefore, there is an urgent need for a high-water-level saline soil frozen soil area railway station yard subgrade waterproof and drainage structure to solve this problem. SUMMARY
[0003] Therefore, the purpose of the present application is to realize the rapid discharge of water, prevent the infiltration of groundwater and upper rainfall, and weaken the influence of water on the stability of the subgrade by setting the lower drainage layer, the conventional filling layer, the subgrade bottom layer, the upper water barrier layer, the upper filler layer and the rapid flow groove.
[0004] To achieve the above purpose, the present application realizes the following technical scheme:
[0005] The high-water-level saline soil frozen soil area railway station yard subgrade waterproof and drainage structure is characterized by comprising a filling layer, the filling layer comprising a lower drainage layer, a conventional filling layer, a subgrade bottom layer, an upper water barrier layer and an upper filler layer which are sequentially arranged from bottom to top and inclined outward; the filling layer is trapezoidal, and an outer side of the filling layer is provided with a rapid flow groove, an outer lower part of the lower drainage layer is provided with a U-shaped side ditch, and the rapid flow groove extends to the U-shaped side ditch; the lower drainage layer comprises a crushed stone cushion layer, a composite waterproof and drainage board and a crushed stone layer which are sequentially arranged from bottom to top, the composite waterproof and drainage board is provided with needle-punched perforated geotextile on both upper and lower sides, and the inside of the crushed stone layer is provided with a plastic blind ditch which is arranged in a longitudinal and transverse staggered manner, and the outer side of the plastic blind ditch is folded downward and extends outward to the U-shaped side ditch.
[0006] The upper water barrier layer comprises a first medium sand layer, a second waterproof geotextile, a PVC waterproof and drainage board, a second permeable geotextile and a second medium sand layer which are sequentially arranged from bottom to top; the PVC waterproof and drainage board introduces water into the upper part of the rapid flow groove.
[0007] Preferably, the composite waterproof and drainage board is fixed by using U-shaped nails when being overlapped; the outer side of the plastic blind ditch is wrapped with a first water permeable geotextile; and the gravel cushion layer is open-graded gravel with a particle size of 1 cm and a permeability coefficient greater than 0.5 cm / s.
[0008] Preferably, the rapid flow channel comprises a channel surface layer, the lower part of the channel surface layer is provided with a gravel cushion layer, the lower part of the gravel cushion layer is provided with a plurality of tenons, and the rapid flow channel is provided at every 10 m along the longitudinal direction of the line.
[0009] Preferably, the PVC waterproof and drainage board is provided with a flow guide hole, the overlapping length of the second water permeable geotextile is greater than 10 cm, the thickness of the second medium-coarse sand layer is 10 cm, the thickness of the first medium-coarse sand layer is 5 cm, the second waterproof geotextile is overlapped by using a waterproof adhesive material, and the overlapping length is greater than 10 cm.
[0010] Preferably, the single board width of the PVC waterproof and drainage board is 1000 mm, the surface tension coefficient is 0.07 N / m, the board thickness is 2 mm, the flow guide hole is arranged within the middle 800 mm, the material slotting width is 0.3 mm, the flow guide hole diameter is 1 mm, the hole bottom distance from the back side of the board is 0.5 mm; the flow guide hole is directed to the outer side, and the water body is introduced into the upper part of the rapid flow channel through the drainage pipe.
[0011] Preferably, the U-shaped side ditch comprises a rubber material prefabricated part and a first waterproof geotextile arranged in sequence from inside to outside, the outer part of the first waterproof geotextile is filled with coarse particle filler, the thickness of the coarse particle filler is 10-15 cm, the first waterproof geotextile is a cloth-film composite geotextile with a thickness of 0.2-0.3 mm; and the outer side of the U-shaped side ditch is provided with a water retaining twist.
[0012] Preferably, the lower hydrophobic layer, the conventional filling layer, the base bed bottom layer, the upper water-resisting layer and the upper filler layer are all inclined from the middle to both sides with an inclination gradient of 4%.
[0013] As described above, due to the adoption of the above technical solutions, the application has the following beneficial effects:
[0014] The reciprocating action of the freezing and thawing of the ground soil body can be effectively prevented, so as to avoid the cracks and deformation of the roadbed drainage engineering measures, the water is effectively prevented from seeping into the soil along the deformation part or the cracks of the drainage ditch, and the stability of the roadbed is improved. By arranging the lower drainage layer and the upper water-resisting layer, the drainage of the roadbed is strengthened, the time for discharging the upper layer of stagnant water is shortened, the rising of underground capillary water is blocked, the influence of water on the stability of the roadbed is weakened, the overall stability of the roadbed is effectively ensured, meanwhile, the strength and rigidity of the roadbed are increased as the reinforcing material, and the engineering cost is greatly reduced; the U-shaped side ditch adopts the semi-flexible and semi-rigid structure of the geotextile, the coarse particle filler and the prefabricated piece, in addition to the good drainage performance of the material itself, the U-shaped side ditch also has high safety and construction convenience and sustainability, and can protect the roadbed slope from the influence of temperature difference, humidity change and rainwater erosion. BRIEF DESCRIPTION OF DRAWINGS
[0015] Figure 1 FIG. 1 is a sectional structure schematic diagram of the roadbed drainage structure of the present application;
[0016] Figure 2 FIG. 2 is a detailed marking schematic diagram of the sectional structure of the roadbed drainage structure of the present application;
[0017] Figure 3 FIG. 3 is an A-A sectional schematic diagram of the present application; Figure 1
[0018] Figure 4 FIG. 4 is a B-B sectional schematic diagram of the present application; Figure 1
[0019] Figure 5 FIG. 5 is a U-shaped side ditch sectional schematic diagram of the present application;
[0020] Figure 6 FIG. 6 is a plastic blind ditch sectional schematic diagram of the present application;
[0021] Figure 7 FIG. 7 is a PVC drainage plate sectional schematic diagram of the present application;
[0022] Figure 8 FIG. 8 is a U-shaped nail style schematic diagram of the present application;
[0023] Figure 9 FIG. 9 is a plane and sectional style and arrangement schematic diagram of the composite drainage plate of a preferred embodiment of the present application.
[0024] In the figure: 1, lower hydrophobic layer; 1-1, gravel cushion; 1-2, needle-punched geotextile; 1-2-1, first needle-punched geotextile; 1-2-2, second needle-punched geotextile; 1-3, composite drainage board; 1-4, plastic blind drain; 1-5, gravel layer; 1-6, first permeable geotextile; 2, U-shaped edge ditch; 2-1, first waterproof geotextile; 2-2, coarse-grained filler; 2-3, rubber preformed piece; 3, conventional filling layer; 4, base bottom layer; 5, upper water-resisting layer; 5-1, PVC drainage board; 5-1-1, flow guide hole; 5-2, second waterproof geotextile; 5-3, first medium-coarse sand layer; 5-4, second permeable geotextile; 5-5, second medium-coarse sand layer; 6, upper filler layer; 7, rapid flow channel; 7-1, drainage pipe; 7-2, rapid flow channel surface layer; 7-3, sand and gravel cushion; 7-4, tenon. DETAILED DESCRIPTION
[0025] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all the other embodiments obtained by a person of ordinary skill in the art without any creative work are within the scope of protection of the present application.
[0026] As Figures 1-9As shown, the present application provides a technical solution: in the high water level saline soil frozen soil area, it is difficult to find, maintain and repair in time under the influence of highland working conditions, which can effectively prevent the reciprocal action of ground soil frost heaving and thawing, thereby avoiding the cracks and deformation of the roadbed drainage engineering measures, effectively preventing water from seeping into the soil along the drainage ditch deformation part or crack, thereby improving the stability of the roadbed. Secondly, for groundwater, appropriate measures such as water isolation and drainage should be taken according to local conditions to lower the groundwater level and dredge seepage water. By setting the upper water isolation layer, the surface drainage of the roadbed is strengthened, and the time for the upper layer of stagnant water to drain is shortened. By setting the drainage system in the lower drainage layer, the rising of underground water can be prevented, and the overall stability of the roadbed can be effectively guaranteed; in order to reduce the water infiltration of the drainage ditch and make the drainage channel adapt to the deformation of frost heaving and thawing, the U-shaped ditch prefabricated lining is mainly made of rubber with high durability and high strength, and the impermeable geotextile is laid at the bottom of the prefabricated lining. On the one hand, it can prevent the infiltration of water accumulated in the channel, and on the other hand, it can make the water accumulated in the channel drain along the longitudinal slope of the channel. At the same time, under the action of the certain longitudinal drainage slope of the channel, there will be no excessive water accumulation at the thawing deformation part. The coarse particle filler laid under the geotextile can better reduce the frost heaving deformation of the soil on the outside of the channel, and play a protective role for the prefabricated component. In addition to its good drainage performance, it also has high safety, construction convenience and sustainability, and can also protect the roadbed slope from the influence of temperature difference, humidity change and rainwater erosion. The bottom surface of the hydraulic chute is roughened, and a plurality of tenons are arranged at the bottom of the hydraulic chute, which can effectively prevent the hydraulic chute from sliding downward under its own gravity, thereby improving the stability of the hydraulic chute.
[0027] Referring to Figure 1 , 2 , 3 and 6, the roadbed drainage structure of the high water level saline soil frozen soil area railway station, comprising a filling layer, the filling layer comprising a lower drainage layer 1, a conventional filling layer 3, a base bottom layer 4, an upper water isolation layer 5 and an upper filling layer 6 arranged from bottom to top and inclined outward; the filling layer is trapezoidal, and the outer side is provided with a hydraulic chute 7, and the outer side of the lower drainage layer 1 is provided with a U-shaped ditch 2, and the hydraulic chute 7 extends to the U-shaped ditch 2; the lower drainage layer 1 comprises a gravel cushion layer 1-1, a composite drainage board 1-3 and a gravel layer 1-5 arranged from bottom to top, and the upper and lower sides of the composite drainage board 1-3 are provided with needle-punched geotextile 1-2, that is, the lower side of the composite drainage board 1-3 is provided with a first needle-punched geotextile 1-2-1, and the upper side is provided with a second needle-punched geotextile 1-2-2, and the inside of the gravel layer 1-5 is provided with a plastic blind ditch 1-4, and the plastic blind ditch 1-4 is arranged longitudinally and transversely, and the outer side is folded downward and extends outward to the U-shaped ditch 2;
[0028] By setting the lower hydrophobic layer 1, groundwater can be isolated to avoid the infiltration of groundwater to the foundation. The gravel cushion 1-1 has a large pore to prevent the foundation from freezing and expanding due to water contact, and to prevent the upward migration of groundwater through soil pores. The upper part of the gravel cushion 1-1 is provided with a composite waterproof drainage board 1-3, which can prevent the upward migration of groundwater and the downward migration of potential water in the upper filling layer, thereby damaging the foundation. The upper water body is transported to the U-shaped side ditch 2 by the longitudinally and transversely arranged plastic blind ditch 1-4, thereby greatly protecting the structural stability of the filling layer and preventing frost heaving.
[0029] In a preferred embodiment, the plane and cross-sectional pattern and arrangement of the composite waterproof drainage board 1-3 are as shown in Figure 9 , with a water-resistant geomembrane on the lower side to improve the waterproofing effect in combination with horizontal / oblique ribs.
[0030] Referring to Figure 4 , the upper water-resistant layer 5 includes a first medium sand layer 5-3, a second waterproof geotextile 5-2, a PVC waterproof drainage board 5-1, a second permeable geotextile 5-4, and a second medium sand layer 5-5 arranged in order from bottom to top; the PVC waterproof drainage board 5-1 introduces water into the upper part of the rapid flow chute 7. Through the upper second medium sand layer 5-5 for preliminary filtration, and the second permeable geotextile 5-4 for secondary filtration, the effect of only draining water but not soil is achieved, while the second waterproof geotextile 5-2 is provided to prevent the downward migration of water, and the first medium sand layer 5-3 serves as a buffer.
[0031] In the embodiments of the present application: the composite waterproof drainage board 1-3 is fixed by U-shaped nails when lapping, and a preferred style of the U-shaped nails is shown in Figure 8 ; the outer side of the plastic blind ditch 1-4 is wrapped with a first permeable geotextile 1-6, which plays the role of only draining water but not sand by wrapping the permeable geotextile, thereby avoiding the clogging of the plastic blind ditch 1-4 by silt; the gravel cushion 1-1 is an open-graded gravel with a particle size of 1 cm, and the permeability coefficient is greater than 0.5 cm / s, which ensures the stability of the foundation and the waterproofing effect. When laying the composite waterproof drainage board 1-3, it is laid in the order of the cross-sectional direction and necessary lapping is performed. The lapping should be in the direction of the drainage horizontal slope downward to avoid the uplift of the geosynthetic material, and the material can be laid flat in areas with low bearing capacity and fixed with U-shaped nails.
[0032] In the embodiment of the present application: the rapid flow tank 7 comprises a tank surface layer 7-2, the tank surface layer 7-2 is prefabricated with concrete, which can ensure the drainage effect, in order to solve the frost heaving problem in the permafrost region, a gravel cushion layer 7-3 is arranged at the lower part of the tank surface layer 7-2, the thickness of the gravel cushion layer 7-3 should reach 10 cm, the gravel cushion layer 7-3 plays a frost heaving buffering role, which can effectively prevent and control the frost heaving damage of the tank surface layer 7-2, a plurality of tenons 7-4 are arranged at the lower part of the gravel cushion layer 7-3, the tenons 7-4 can avoid landslide phenomenon, and the rapid flow tank 7 is arranged every 10 m along the longitudinal direction of the line.
[0033] In the embodiment of the present application: the PVC waterproof drainage plate 5-1 is provided with a flow guide hole 5-1-1, the overlapping length of the second water permeable geotextile 5-4 is greater than 10 cm, the thickness of the second medium coarse sand layer 5-5 is 10 cm, the thickness of the first medium coarse sand layer 5-3 is 5 cm, the second waterproof geotextile 5-2 is overlapped by using waterproof adhesive material, and the overlapping length is greater than 10 cm. The second water permeable geotextile 5-4 is overlapped to avoid soil particles from entering the PVC waterproof drainage plate 5-1 from the gap, thereby causing the flow guide hole 5-1-1 to be blocked,
[0034] Referring to Figure 7 In a preferred embodiment, the single plate width of the PVC waterproof drainage plate 5-1 is 1000 mm, the surface tension coefficient is 0.07 N / m, the plate thickness is 2 mm, the flow guide hole 5-1-1 is arranged in the middle 800 mm, both sides are reserved for overlapping, the material slot width is 0.3 mm, the flow guide hole 5-1-1 has a hole diameter of 1 mm, and the hole bottom is 0.5 mm away from the back side of the plate; the flow guide hole 5-1-1 faces the outside, and the water body is introduced into the upper part of the rapid flow tank 7 through the drainage pipe 7-1.
[0035] Referring to Figure 5 In the embodiment of the present application: the U-shaped side ditch 2 comprises rubber material prefabricated parts 2-3 and first waterproof geotextile 2-1 arranged from inside to outside, the rubber material prefabricated parts 2-3 are loosely connected without cementing effect, the connection is simple and easy for construction, the first waterproof geotextile 2-1 can avoid water infiltration and underground water entering the inside of the U-shaped side ditch 2, the outside of the first waterproof geotextile 2-1 is filled with coarse particle filler 2-2, the thickness of the coarse particle filler 2-2 is 10-15 cm, and the deformation of the U-shaped side ditch 2 caused by frost heaving can be avoided by arranging the coarse particle filler 2-2. The first waterproof geotextile 2-1 is a cloth-film composite geotextile with a thickness of 0.2-0.3 mm; the cross section of the U-shaped side ditch 2 is in the shape of “U”, the upper part is vertical, and the lower part is composed of a semicircle, and the outside of the U-shaped side ditch 2 is provided with a water retaining twist, which can prevent external water from entering the side ditch on the one hand, and can reduce the flow area and accelerate drainage when heavy rain comes on the other hand.
[0036] In the embodiments of the present application: the lower water-draining layer 1, the conventional filling layer 3, the base bottom layer 4, the upper water-resisting layer 5 and the upper filling layer 6 are all inclined from the middle to both sides, and the inclination gradient is 4%. The gradient is set to accelerate the drainage effect. In fact, not only these structures need to be set with gradient, but also the parts constituting these structures and the parts inside these structures need to be set with gradient, such as the gravel cushion layer 1-1, the composite waterproof and drainage board 1-3 and the gravel layer 1-5, the plastic blind ditch 1-4, the first medium-coarse sand layer 5-3, the second waterproof geotextile 5-2, the PVC waterproof and drainage board 5-1, the second permeable geotextile 5-4 and the second medium-coarse sand layer 5-5, etc. all need to be set with a gradient of 4% to increase the drainage effect.
[0037] The construction method of the high-water-level saline soil and frozen soil area railway station yard roadbed waterproof and drainage structure provided by the present application will be further described below in combination with a specific embodiment. The method comprises the following steps:
[0038] S1, preparation work: the preparation work is divided into a prefabrication stage and a site treatment stage. The prefabrication stage is to prefabricate the modules for the U-shaped side ditch 2, and the prefabrication stage is carried out in a factory. First, the template for the U-shaped side ditch 2 is prefabricated according to the drawings, the template is coated with a release agent to form a mold, the mold is placed in rubber and then poured, and after hardening, the mold is removed to form a rubber prefabricated part 2-3. The site treatment stage needs to be combined with the design drawings for on-site construction, which mainly includes leveling the existing foundation to have a certain gradient, preferably a 4% outward-inclined slope, and excavating the plastic blind ditch 1-4 and the U-shaped side ditch 2 to lay the groove;
[0039] S2, construction of the lower water-draining layer 1: after the preparation work is completed, the gravel cushion layer 1-1 is constructed, which is filled in two layers, and the particle size of the open-graded gravel is 1 cm, and the permeability coefficient is greater than 0.5 cm / s. Then the composite waterproof and drainage board 1-3 and the needle-punched perforated geotextile 1-2 on both sides thereof are laid, and the laying is synchronized with the laying of the lower bend of the plastic blind ditch 1-4. When laying the composite waterproof and drainage board 1-3, it is laid in the order of the cross-sectional direction, and necessary lap joints are made. The lap joints should be in the direction of the drainage horizontal slope downward to avoid the uplift of the geosynthetic material. In the section with low bearing capacity, the material can be laid flat and fixed with U-shaped nails. After the laying is completed, the gravel layer 1-5 is continued to be laid, and the horizontal section of the plastic blind ditch 1-4 is simultaneously laid;
[0040] S3, construction of the filling layer: it is divided into the construction of the conventional filling layer 3 and the base bottom layer 4. The filling materials meeting the requirements are selected, and the filling materials are filled on the roadbed in layers according to the design requirements and the construction specifications. The thickness of each layer should not be too thick. After the filling of each layer is completed, the specified compactness is ensured. During the process of layer-by-layer filling, the water content of the filling materials should be controlled to ensure the quality of compaction and the smoothness of the internal drainage channels of the materials;
[0041] S4, the upper water-resisting layer 5 and the upper filler layer 6 construction: on the base bed 4, the first medium-coarse sand layer 5-3 with a thickness of 5 cm, the second waterproof geotextile 5-2, the PVC waterproof drainage plate 5-1, the second permeable geotextile 5-4 and the second medium-coarse sand layer 5-5 with a thickness of 10 cm are sequentially laid, wherein the waterproof adhesive material is used when the second waterproof geotextile 5-2 is overlapped, the overlapping length is greater than 10 cm, and the overlapping width of the second permeable geotextile 5-4 needs to be more than 10 cm. The sand layer construction adopts the method of spreading first and then rolling to ensure that the design standard is reached;
[0042] S5, the quick-flowing groove 7 and the side ditch construction: the correct position of the quick-flowing groove 7 is determined according to the design drawing, the size of the quick-flowing groove 7 is determined to determine the size of the foundation pit and the reserved formwork position, the slope reaches the design slope, the foundation pit is perpendicular to the line direction, then the wire is hung for excavation, and the over-excavation and under-excavation are avoided. The inclined surface should be dug on both sides of the quick-flowing groove 7 template, which is in the shape of inverted "8", so as to prevent the soil from entering the groove from both sides. The sand and gravel cushion layer 7-3 is laid flat, the sand and gravel is evenly laid in the foundation pit, the thickness should reach 10 cm, after the laying is completed, the water is sprinkled, the compaction is compacted, the leveling is leveled, the formwork is erected and the concrete is poured. The longitudinal slope of the U-shaped side ditch 2 ditch bottom is preferably consistent with the longitudinal slope of the route, and is not less than 0.3%, the length depends on the precipitation, but the longest should not be more than 500 m. The prefabricated module is used to complete the U-shaped side ditch 2 construction in the groove, the first waterproof geotextile 2-1 needs to be added below to prevent infiltration, the coarse-grained filler 2-2 is arranged at the lower part of the first waterproof geotextile 2-1, and the first waterproof geotextile 2-1 is preferably a waterproof reinforced composite geomembrane.
[0043] The above is only the preferred specific embodiment of the present application, but the protection scope of the present application is not limited to this, any person skilled in the art can make equivalent replacement or change according to the technical scheme and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered in the protection scope of the present application.
Claims
1. A high water level saline soil frozen soil area railway station yard subgrade drainage structure, characterized in that: The embankment comprises, from bottom to top, a lower water-permeable layer (1), a conventional embankment layer (3), a base bottom layer (4), an upper water-resisting layer (5) and an upper filler layer (6) arranged in sequence and inclined to the outside; the embankment is trapezoidal in shape and is provided with a torrent channel (7) on the outside, the lower part of the outer side of the lower water-permeable layer (1) is provided with a U-shaped side ditch (2), and the torrent channel (7) extends to the U-shaped side ditch (2); the lower water-permeable layer (1) comprises, from bottom to top, a crushed stone cushion layer (1-1), a composite waterproof and drainage board (1-3) and a crushed stone layer (1-5), the upper and lower sides of the composite waterproof and drainage board (1-3) are provided with needle-punched perforated geotextile (1-2), and the inside of the crushed stone layer (1-5) is clamped with a plastic blind ditch (1-4), which is arranged longitudinally and transversely, and the outer side is folded downward and outward to the U-shaped side ditch (2). The upper water-resisting layer (5) comprises, from bottom to top, a first medium-coarse sand layer (5-3), a second waterproof geotextile (5-2), a PVC waterproof and drainage board (5-1), a second water-permeable geotextile (5-4) and a second medium-coarse sand layer (5-5); the PVC waterproof and drainage board (5-1) introduces water into the upper part of the torrent channel (7).
2. The high-water table, saline soil, permafrost region railway yard roadbed drainage structure of claim 1, wherein: The composite waterproof and drainage board (1-3) is fixed by U-shaped nails when overlapping; the outer side of the plastic blind ditch (1-4) is wrapped with a first water-permeable geotextile (1-6); the crushed stone cushion layer (1-1) is open-graded crushed stone with a particle size of 1 cm, and the permeability coefficient is greater than 0.5 cm / s.
3. The high-water table, saline soil, permafrost region railway yard roadbed drainage structure of claim 1, wherein: The torrent channel (7) comprises a channel surface layer (7-2), the lower part of the channel surface layer (7-2) is provided with a sand and gravel cushion layer (7-3), the lower part of the sand and gravel cushion layer (7-3) is provided with a plurality of tenons (7-4), and the torrent channel (7) is provided with one every 10 m along the longitudinal direction of the line.
4. The high-water table, saline soil, permafrost region railway yard roadbed drainage structure of claim 3, wherein: The PVC waterproof and drainage board (5-1) is provided with a flow guide hole (5-1-1), the overlapping length of the second water-permeable geotextile (5-4) is greater than 10 cm, the thickness of the second medium-coarse sand layer (5-5) is 10 cm, the thickness of the first medium-coarse sand layer (5-3) is 5 cm, and the waterproof adhesive material is used when the second waterproof geotextile (5-2) is overlapped, and the overlapping length is greater than 10 cm.
5. The high-water table, saline soil, permafrost region railway yard roadbed drainage structure of claim 4, wherein: The single board width of the PVC waterproof and drainage board (5-1) is 1000 mm, the surface tension coefficient is 0.07 N / m, the board thickness is 2 mm, the flow guide hole (5-1-1) is arranged within the middle 800 mm, the material slot width is 0.3 mm, the flow guide hole (5-1-1) has a hole diameter of 1 mm, and the hole bottom is 0.5 mm away from the back side of the board; the flow guide hole (5-1-1) faces the outside, and the water body is introduced into the upper part of the torrent channel (7) through the drainage pipe (7-1).
6. The high-water table, saline soil, permafrost region railway yard roadbed drainage structure of claim 1, wherein: The U-shaped side ditch (2) comprises a rubber material prefabricated part (2-3) and a first waterproof geotextile (2-1) arranged in sequence from inside to outside, the outside of the first waterproof geotextile (2-1) is filled with a coarse-grained filler (2-2), the thickness of the coarse-grained filler (2-2) is 10-15 cm, the first waterproof geotextile (2-1) is a cloth-film composite geotextile with a thickness of 0.2-0.3 mm; the outer side of the U-shaped side ditch (2) is provided with a water retaining twist.
7. The high-water table, saline soil, permafrost region railway yard roadbed drainage structure of claim 1 wherein: The lower hydrophobic layer (1), the conventional filling layer (3), the base bed bottom layer (4), the upper water isolation layer (5) and the upper filler layer (6) are all inclined from the middle to both sides, and the inclination gradient is 4%.