A dam slope drainage hole structure for geomembrane impervious dam

Abstract

The utility model discloses a dam slope drainage hole structure for geomembrane seepage control dam, including the dam slope body and the geomembrane seepage control layer of covering on the slope face of dam slope body, a plurality of groups of drainage pipeline groups are arrayed distribution with different inclination angle obliquely through the dam slope body and extend to the slope face, and the pipe orifice end of drainage pipeline is flush with the slope face of dam slope body, every group of drainage pipeline groups is transversely arranged, and the drainage pipeline in every group of drainage pipeline groups keeps same inclination, and forms the equal angle drainage array, the seepage control connecting sleeve includes the socket part and the compression part, the socket part is sleeved in the top end of drainage pipeline and forms the annular interference fit, and the outer edge of compression part and geomembrane seepage control layer form continuous seepage control interface through hot melt welding, the utility model can accurately match the seepage water pressure of different regions of dam slope, improves the drainage capacity of slope bottom high water pressure area, and effectively avoids the bulging or breakage of seepage control layer caused by local water pressure accumulation.

Description

Technical Field

[0001] This utility model relates to the field of water conservancy engineering technology, specifically to a dam slope drainage hole structure for geomembrane seepage prevention dams. Background Technology

[0002] Geomembrane-lined dams are widely used in modern water conservancy projects. Their core function is to block water seepage through polymer impermeable materials, ensuring the structural stability of the dam slope. As a crucial supporting structure, the dam slope drainage system must effectively drain seepage water to prevent internal water pressure accumulation that could lead to the failure of the impermeable layer. In existing technologies, drainage holes are typically arranged vertically or at a single angle to meet foundation drainage requirements. With the increasing prevalence of complex engineering scenarios such as high dams and steep slopes, higher demands are placed on the adaptability, durability, and synergy with the impermeable layer of the drainage system, necessitating optimized design to match different hydrogeological conditions.

[0003] Currently, traditional dam slope drainage hole structures mostly employ a single inclination angle, resulting in uneven drainage efficiency with slope length and a tendency for localized water accumulation. Weak points for leakage easily form at the connection between the pipes and the impermeable layer, and the reliability of hot-melt welding is insufficient. Furthermore, existing drainage holes lack refined designs for water flow guidance and filtration systems, potentially leading to clogging or filter failure during long-term use. Especially on steep slopes, it is difficult to simultaneously ensure the structural strength of conventional drainage pipes and the sealing performance of the impermeable sleeve, affecting the overall project lifespan and hindering the widespread application of geomembrane-lined dams in high-standard projects. Utility Model Content

[0004] The technical problem to be solved by this utility model is to provide a drainage hole structure for the slope of a geomembrane seepage-proof dam, which solves the problems in the prior art such as easy formation of weak points for leakage at the connection between the pipe and the seepage-proof layer, insufficient reliability of hot melt welding, possible sludge blockage or reverse filtration failure during long-term use, and impact on the overall project life.

[0005] To solve the above technical problems, the present invention adopts the following technical solution:

[0006] A drainage hole structure for a geomembrane-lined dam slope includes the dam slope body and a geomembrane seepage-proof layer covering the slope surface of the dam slope body.

[0007] Multiple sets of drainage pipes are arranged in an array, penetrating the dam slope at different angles and extending to the slope surface. The ends of the drainage pipes are flush with the slope surface of the dam slope. Each set of drainage pipes is arranged laterally.

[0008] Along the slope from top to bottom, the angle between each group of drainage pipes and the dam slope increases gradually.

[0009] The drainage pipes in each group of drainage pipes maintain the same inclination angle, forming an equal-angle drainage array.

[0010] The seepage-proof connecting sleeve includes a socket part and a pressing part. The socket part is sleeved on the top of the drainage pipe to form an annular interference fit. The outer edge of the pressing part is heat-fused to the geomembrane seepage-proof layer to form a continuous seepage-proof interface.

[0011] Furthermore, the cross-section of the drainage pipe is conical, with the diameter at the end closer to the dam slope being larger than that at the end farther from the dam slope. The taper angle of the drainage pipe is 5° to 15°, and the taper angle of the drainage pipe increases sequentially from the top of the slope to the bottom of the slope.

[0012] Furthermore, the circumferential surface of the pressed part has several protrusions evenly distributed along the circumference. The top of the protrusions is higher than the surface of the geomembrane impermeable layer, forming a three-dimensional pressed structure. The protrusions are partially embedded in the membrane body of the geomembrane impermeable layer.

[0013] Furthermore, the drainage pipe is provided with a mesh reinforcement layer and a reverse filter geotextile at one end near the slope of the dam body, with the reverse filter geotextile arranged above the mesh reinforcement layer.

[0014] Furthermore, the inner wall of the drainage pipe is provided with a spiral guide groove, and the pitch of the spiral guide groove decreases along the insertion direction.

[0015] Furthermore, the geomembrane seepage prevention layer is made of high-density polyethylene membrane and is laid continuously along the slope of the dam slope body by hot-melt welding.

[0016] Furthermore, the anti-seepage connecting sleeve is injection molded from modified polyethylene, and the pressing part has a disc structure.

[0017] Furthermore, the mesh reinforcement layer is made of hot-rolled ribbed steel bars welded together, and the reverse filter geotextile is made of short-fiber needle-punched nonwoven fabric.

[0018] Compared with the prior art, the present invention, by adopting the above technical solution, has the following technical effects:

[0019] 1. This utility model adopts a drainage pipe with an increasing inclination angle and tapered gradient from the top to the bottom of the slope, which can accurately match the seepage water pressure in different areas of the dam slope (the water pressure at the bottom of the slope is significantly higher than that at the top of the slope). The larger inclination angle and tapered gradient can reduce water flow resistance and improve the drainage capacity of the high water pressure area at the bottom of the slope. The single row of equal angle array ensures the uniformity of drainage in the same slope section and effectively avoids the bulging or damage of the anti-seepage layer caused by the accumulation of local water pressure.

[0020] 2. This utility model adopts a gradient structural design and a three-dimensional pressure-bonded seepage prevention structure, which can adapt to the settlement and temperature deformation of the dam body under complex scenarios such as high dams and steep slopes. The gradient distribution of inclination angle and taper is adapted to the mechanical environment of different slope sections. The protruding fused structure buffers the deformation stress through flexible connection, which solves the problem of traditional rigid drainage holes being prone to breakage or leakage due to dam deformation, and has a wider range of applications. Attached Figure Description

[0021] Figure 1 This is an overall structural diagram of the present invention.

[0022] Figure 2 This is a cross-sectional view of the present invention.

[0023] Figure 3 This is an enlarged view of a section of the present invention.

[0024] Attached diagram labels: 1. Dam slope body; 2. Geomembrane seepage prevention layer; 3. Drainage pipe; 4. Seepage prevention connection sleeve; 5. Socket part; 6. Pressing part; 7. Protrusion; 8. Mesh reinforcement layer; 9. Reverse filter geotextile; 10. Spiral diversion channel. Detailed Implementation

[0025] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0026] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless defined as herein.

[0027] To achieve the above objectives, this utility model proposes a drainage hole structure for the slope of a geomembrane-lined seepage-proof dam, such as... Figure 1 As shown, the structure includes the dam slope body 1 and a geomembrane anti-seepage layer 2 covering the slope surface of the dam slope body 1. The surface of the dam slope body 1 is an inclined surface. The geomembrane anti-seepage layer 2 is placed on the inclined surface and covers it. The geomembrane anti-seepage layer 2 is made of high-density polyethylene film and is laid continuously along the slope surface of the dam slope body 1 by hot-melt welding. The joint width is not less than 100mm, ensuring that the dam slope body 1 is completely covered and blocking the direct infiltration of external water bodies.

[0028] like Figure 2As shown, multiple sets of drainage pipes arranged in an array penetrate the dam slope body 1 at different angles and extend to the slope surface. The ends of the drainage pipes 3 are flush with the slope surface of the dam slope body 1 to avoid water accumulation caused by protrusions or depressions. Each set of drainage pipes is arranged laterally. Along the slope top to bottom, the angle between each set of drainage pipes and the dam slope surface increases gradually. For example, the angle of the first row at the top of the slope is 30°, and it increases by 5° for each subsequent row, reaching 60° for the last row at the bottom of the slope.

[0029] The drainage pipes 3 in each drainage pipe group maintain the same inclination angle, forming an equal-angle drainage array. This design can match the seepage water pressure in different areas of the dam slope body 1 (the water pressure at the bottom of the slope is significantly higher than that at the top of the slope), and improve the downstream drainage capacity by increasing the inclination angle, thus avoiding local water accumulation.

[0030] The drainage pipe 3 is made of high-density polyethylene and has a conical cross-section. The diameter of the end closer to the slope of the dam body 1 is larger than that of the end farther away from the slope of the dam body 1. The taper angle of the drainage pipe 3 is 5° to 15°, and the taper angle of the drainage pipe 3 increases gradually from the top of the slope to the bottom of the slope. The conical design can utilize the gradually expanding channel effect to accelerate the water flow out, while the gradual increase in the taper angle matches the water pressure distribution. The water pressure is high at the bottom of the slope, and a larger taper can reduce the water flow resistance.

[0031] The anti-seepage connecting sleeve 4 is made of modified polyethylene injection molding. It includes a socket part 5 and a pressing part 6. The inner diameter of the socket part 5 is slightly smaller than the outer diameter of the top of the drainage pipe 3. The socket part 5 is sleeved on the top of the drainage pipe 3 and forms an annular interference fit. The material elastic deformation achieves a preliminary seal, preventing water seepage inside the dam slope body 1 from leaking into the socket part 5 along the outer wall of the drainage pipe 3. The pressing part 6 is a disc structure. Its outer edge is hot-melt welded to the geomembrane anti-seepage layer 2 with a hot air gun to form a continuous and uninterrupted anti-seepage interface, incorporating the connection between the drainage pipe 3 and the geomembrane into the overall anti-seepage system.

[0032] The circumferential side of the pressing part 6 has several protrusions 7 evenly distributed around the circumference. The top of the protrusions 7 is higher than the surface of the geomembrane impermeable layer 2, forming a three-dimensional pressing structure. The protrusions 7 are partially fused into the geomembrane impermeable layer 2. During the welding process, the protrusions 7 are partially fused into the geomembrane impermeable layer 2 under the action of heat and pressure, which can enhance the mechanical interlocking force between the pressing part 6 and the geomembrane, resist the tensile force caused by the settlement or temperature deformation of the dam slope body 1, and avoid the problem of easy cracking in traditional planar welding.

[0033] like Figure 3 As shown, a perforated steel reinforcement layer 8 and a reverse filter geotextile 9 are provided at one end of the drainage pipe 3 near the slope of the dam slope body 1. The perforated steel reinforcement layer 8 is made of hot-rolled ribbed steel bars and is laid on the inside of the drainage pipe 3 port to provide rigid support and prevent the reverse filter geotextile 9 from being damaged by high-speed water flow.

[0034] The reverse filter geotextile 9 is made of short fiber needle-punched nonwoven fabric, which covers the mesh steel reinforcement layer 8 and is attached to the inner wall of the drainage pipe 3. Its permeability coefficient is 1-2 orders of magnitude greater than that of the soil material of the dam slope body 1, which can achieve the filtration effect of water passing through but soil not passing through, and prevent soil particles of the dam slope body 1 from entering the drainage pipe 3 with the water flow and causing siltation.

[0035] The inner wall of the drainage pipe 3 is provided with a spiral guide groove 10. The pitch of the spiral guide groove 10 decreases along the insertion direction. This design can guide the water flow to form a spiral flow state, accelerate the water flow speed through centrifugal force, and adapt to the speed change of the water flow from fast to slow by using the decreasing pitch, thereby reducing the probability of sediment deposition in the drainage pipe 3 and further improving the anti-clogging ability.

[0036] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A drainage hole structure for the slope of a geomembrane-lined dam, characterized in that, It includes the dam slope body (1) and the geomembrane seepage prevention layer (2) covering the slope surface of the dam slope body (1). Multiple sets of drainage pipes are arranged in an array and penetrate the dam slope body (1) at different angles and extend to the slope surface. The pipe ends of the drainage pipes (3) are flush with the slope surface of the dam slope body (1). Each set of drainage pipes is arranged in a transverse direction. Along the slope from top to bottom, the angle between each group of drainage pipes and the dam slope increases gradually. The drainage pipes (3) in each drainage pipe group maintain the same inclination angle to form an equal-angle drainage array; The seepage-proof connecting sleeve (4) includes a socket part (5) and a pressing part (6). The socket part (5) is sleeved on the top of the drainage pipe (3) and forms an annular interference fit. The outer edge of the pressing part (6) and the geomembrane seepage-proof layer (2) are heat-melted to form a continuous seepage-proof interface.

2. The dam slope drainage hole structure for geomembrane seepage-proof dams according to claim 1, characterized in that, The cross-section of the drainage pipe (3) is conical, and the diameter of the end near the slope of the dam body (1) is larger than that of the end away from the slope of the dam body (1). The taper angle of the drainage pipe (3) is 5°~15°, and the taper angle of the drainage pipe (3) from the top of the slope to the bottom of the slope increases row by row.

3. The dam slope drainage hole structure for geomembrane seepage-proof dams according to claim 1, characterized in that, The circumferential side of the pressing part (6) has several protrusions (7) evenly distributed along the circumference. The top of the protrusion (7) is higher than the surface of the geomembrane impermeable layer (2), forming a three-dimensional pressing structure. The protrusion (7) is partially embedded in the membrane body of the geomembrane impermeable layer (2).

4. The dam slope drainage hole structure for geomembrane seepage-proof dams according to claim 1, characterized in that, The drainage pipe (3) is provided with a mesh steel reinforcement layer (8) and a reverse filter geotextile (9) at one end near the slope of the dam slope body (1), and the reverse filter geotextile (9) is placed above the mesh steel reinforcement layer (8).

5. The dam slope drainage hole structure for geomembrane seepage-proof dams according to claim 1, characterized in that, The inner wall of the drainage pipe (3) is provided with a spiral guide groove (10), and the pitch of the spiral guide groove (10) decreases along the insertion direction.

6. The dam slope drainage hole structure for geomembrane seepage-proof dams according to claim 1, characterized in that, The geomembrane seepage prevention layer (2) is made of high-density polyethylene film and is laid continuously along the slope of the dam slope body (1) by hot melt welding.

7. The dam slope drainage hole structure for geomembrane seepage-proof dams according to claim 1, characterized in that, The seepage-proof connecting sleeve (4) is injection molded from modified polyethylene, and the pressing part (6) is a disc structure.

8. The dam slope drainage hole structure for geomembrane seepage-proof dams according to claim 4, characterized in that, The mesh reinforcement layer (8) is made of hot-rolled ribbed steel bars welded together, and the filter geotextile (9) is made of short-fiber needle-punched nonwoven fabric.

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