Undermembrane interception drainage system for bank slope of surface membrane earth dam

Abstract

The utility model provides a face mask earth dam bank slope under-membrane interception drainage system which comprises a geomembrane and further comprises a drainage mat laid below the geomembrane, and a plurality of transverse ditches and longitudinal ditches are arranged below the drainage mat. The transverse ditches comprise a water seepage collecting ditch arranged along the slope toe of the bank slope and a plurality of first intercepting ditches arranged at different bank slope heights, the longitudinal ditches comprise a plurality of second intercepting ditches arranged along the slope direction of the bank slope, and the plurality of second intercepting ditches are communicated between every two transverse ditches which are adjacent up and down; by arranging the drainage mat, the first intercepting ditch, the second intercepting ditch and the water seepage collecting ditch below the geomembrane, the reliability and safety of drainage under the geomembrane are improved, and meanwhile the risk that the geomembrane is reversely jacked and damaged is reduced; by arranging the first drainage solid pipe and the second drainage solid pipe, membrane penetrating water seepage and underground water collection in the drainage mat are mutually independent, and leakage monitoring is facilitated.

Description

Technical Field

[0001] The utility model relates to the technical field of hydropower engineering, in particular to a membrane-submerged drainage system for a bank slope of a membrane earth dam. Background Art

[0002] It is impossible to completely avoid the occasional defective holes that appear during the operation of the geomembrane anti-seepage reservoir in the whole reservoir basin. If there are large leakage spots in the geomembrane and there is no reasonable drainage channel, or the groundwater level line on the bank slope is high, and the groundwater overflows on the slope below the membrane, then the seepage will gradually accumulate and generate a certain pressure at the bottom of the geomembrane. When the reservoir water level drops, the water pressure under the membrane is greater than the pressure outside the membrane, resulting in a reverse top effect. When the water pressure under the membrane is large enough, the geomembrane will bulge and gradually form defective holes, causing water seepage through the membrane and threatening the safe use of the geomembrane. Such accidents are particularly obvious in the reservoir of the pumped storage power station. The water level of the pumped storage power station is in a long-term process of rising and falling. The pressure on the membrane changes greatly, and the repeated stress at the bulge position is prone to fatigue damage. Utility Model Content

[0003] The purpose of this utility model is to overcome the deficiencies of the above-mentioned prior art and provide a membrane interception and drainage system under the slope of a face mask earth dam, which can solve the problem that the pressure on the geomembrane changes greatly and the bulge position is repeatedly stressed and easily causes fatigue damage.

[0004] To this end, the utility model adopts the following technical solutions:

[0005] A membrane-submerged drainage system for a face earth dam bank slope comprises a geomembrane and a drainage mat laid under the geomembrane, a plurality of transverse ditches and a longitudinal ditches are provided under the drainage mat, the bottom of the transverse ditch is connected to the groundwater level, the transverse ditch comprises a seepage collection ditch arranged along the foot of the bank slope and a plurality of first intercepting ditches respectively arranged at different bank slope heights, the longitudinal ditch comprises a plurality of second intercepting ditches arranged along the slope direction, a plurality of the second intercepting ditches are respectively connected between two adjacent transverse ditches, and the side of the seepage collection ditch away from the bank slope is connected to a reservoir bottom water diversion trough.

[0006] On the basis of adopting the above technical solutions, the present invention may also adopt the following further technical solutions, or use these further technical solutions in combination:

[0007] One end of the second intercepting ditch is connected to the bottom of the first intercepting ditch adjacent thereto.

[0008] Geotextiles are laid on the inner walls of the reservoir bottom water diversion trough, the transverse ditch and the longitudinal ditch respectively; the first intercepting ditch and the second intercepting ditch are filled with a first graded gravel and a first clay water barrier layer; the first clay water barrier layer is located between the drainage mat and the first graded gravel; the seepage water collection ditch is filled with a second graded gravel, which is in contact with the lower surface of the drainage mat; a second clay water barrier layer is provided on the side of the seepage water collection ditch away from the bank slope, which is in contact with the lower surface of the geomembrane; the reservoir bottom water diversion trough is filled with a third clay water barrier layer, which is in contact with the lower surface of the geomembrane.

[0009] A first drainage flower pipe is provided at the bottom of several second intercepting ditches near the foot of the slope, and the water outlet end of the first drainage flower pipe is connected to a first drainage solid pipe. One end of the first drainage solid pipe extends to the bottom of the seepage collection ditch. The bottom of the seepage collection ditch is provided with a second drainage solid pipe arranged along its length direction, and the first drainage solid pipe is connected to the second drainage solid pipe.

[0010] The bottom of the seepage water collecting ditch is provided with a second drainage flower pipe arranged along the length direction thereof for collecting water seeping through the membrane.

[0011] The lower part of the water diversion trough at the bottom of the reservoir is provided with a geomembrane seepage collection and drainage pipe and a groundwater seepage collection and drainage pipe arranged along its length direction. The outlet end of the second drainage flower pipe is connected to the geomembrane seepage collection and drainage pipe, and the outlet end of the second drainage pipe is connected to the groundwater seepage collection and drainage pipe.

[0012] The drainage slopes of the first drainage flower pipe, the second drainage flower pipe, the first drainage solid pipe, the second drainage solid pipe, the geomembrane seepage collection and drainage solid pipe, and the groundwater seepage collection and drainage solid pipe are all greater than 1%.

[0013] Compared with the existing technology, the utility model has the following advantages and beneficial effects: it adopts the bank slope sub-membrane interception and drainage system, and by arranging a drainage mat, a first interception ditch, a second interception ditch and a seepage collection ditch under the geomembrane, the reliability and safety of the sub-membrane drainage are improved, and the risk of geomembrane back-up damage is reduced; by arranging the first drainage solid pipe and the second drainage solid pipe, the membrane seepage and groundwater collection in the drainage mat are independent of each other, which is conducive to leakage monitoring, and can warn and analyze the damage of the geomembrane, which is conducive to the inspection and maintenance of the geomembrane. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a typical plan view of the present invention.

[0015] Figure 2This is a typical cross-sectional schematic diagram of the first intercepting ditch and the second intercepting ditch bank slope section of the utility model.

[0016] Figure 3 This is a typical cross-sectional schematic diagram of the first intercepting ditch in the width direction of the utility model.

[0017] Figure 4 This is a typical cross-sectional schematic diagram of the second intercepting ditch in the width direction of the utility model.

[0018] Figure 5 It is a typical cross-sectional schematic diagram of the present utility model.

[0019] Figure 6 It is a typical cross-sectional schematic diagram of the width direction of the water diversion channel at the bottom of the reservoir of the present invention. DETAILED DESCRIPTION

[0020] In order to enable those skilled in the art to better understand the technical solution of the present invention, the preferred implementation scheme of the present invention is described below in conjunction with specific embodiments. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar numbers throughout represent elements with the same or similar functions. However, it should be understood that the drawings are only used for illustrative purposes and cannot be understood as limiting the present invention. In order to better illustrate the present embodiment, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted, and the positional relationship described in the drawings is only used for illustrative purposes and cannot be understood as limiting the present invention.

[0021] The present invention will be further described below with reference to the accompanying drawings and embodiments, but they are not intended to limit the present invention.

[0022] The utility model provides a membrane-submerged drainage system for a face earth dam bank slope, comprising a geomembrane 11 and a drainage mat 3 laid under the geomembrane 11. A plurality of transverse ditches and longitudinal ditches are arranged under the drainage mat 3. The bottom of the transverse ditch is connected to the groundwater level 10. The transverse ditch comprises a seepage collection ditch 5 arranged along the foot of the bank slope and a plurality of first intercepting ditches 1 respectively arranged at different bank slope heights. The longitudinal ditch comprises a plurality of second intercepting ditches 2 arranged along the slope direction of the bank slope. The plurality of second intercepting ditches 2 are respectively connected between two adjacent transverse ditches above and below. The side of the seepage collection ditch 5 away from the bank slope is connected to a reservoir bottom water diversion trough 12.

[0023] The transverse ditch is mainly used to collect groundwater, lower the groundwater level 10, and prevent groundwater from overflowing on the slope.

[0024] The longitudinal ditches are interspersed with the transverse ditches, and the accumulated water in the transverse ditches is collected to the foot of the slope.

[0025] The drainage mat 3 is mainly used to collect the seepage water from the bad points of the geomembrane 11, and collect the seepage water through the membrane to the slope foot through the drainage mat 3.

[0026] One end of the second intercepting ditch 2 is connected to the bottom of the first intercepting ditch 1 above it.

[0027] Geotextiles 8 are laid on the inner walls of the reservoir bottom water diversion trough 12, the transverse ditches and the longitudinal ditches respectively. The first intercepting ditch 1 and the second intercepting ditch 2 are filled with the first graded gravel 91 and the first clay aquifer 41. The first clay aquifer 41 is located between the drainage mat 3 and the first graded gravel 91. The seepage collection ditch 5 is filled with the second graded gravel 92, which is connected to the lower surface of the drainage mat 3. The seepage collection ditch 5 is provided with a second clay aquifer 42 on the side away from the slope, which is connected to the lower surface of the geomembrane 11. The reservoir bottom water diversion trough 12 is filled with a third clay aquifer 43, which is connected to the lower surface of the geomembrane 11.

[0028] The first clay aquiclude 41 is mainly used to separate the water seeping through the membrane and the groundwater, and the second clay aquiclude 42 is used to separate the water seeping from the bottom of the reservoir and the bank.

[0029] A first drainage flower pipe 61 is provided at the bottom of several second intercepting ditches 2 near the foot of the slope. The water outlet end of the first drainage flower pipe 61 is connected to a first drainage solid pipe 71. One end of the first drainage solid pipe 71 extends to the bottom of the seepage collection ditch 5. The bottom of the seepage collection ditch 5 is provided with a second drainage solid pipe 72 arranged along its length direction. The first drainage solid pipe 71 is connected to the second drainage solid pipe 72.

[0030] The bottom of the seepage ditch 5 is provided with a second drainage flower pipe 62 arranged along its length direction for collecting the water seepage through the membrane.

[0031] The lower part of the water diversion trough 12 at the bottom of the reservoir is provided with a geomembrane seepage collection and drainage pipe 73 and a groundwater seepage collection and drainage pipe 74 arranged along its length direction. The outlet end of the second drainage flower pipe 62 is connected to the geomembrane seepage collection and drainage pipe 73, and the outlet end of the second drainage pipe 72 is connected to the groundwater seepage collection and drainage pipe 74.

[0032] The groundwater collected in the horizontal ditch is collected by the first drainage flower pipe 61 and then flows into the first drainage solid pipe 71 and the second drainage solid pipe 72 in sequence, and finally gathers and flows into the groundwater seepage collection drainage solid pipe 74. The membrane seepage collected in the drainage mat 3 is collected by the second drainage flower pipe 62 and then flows into the geomembrane seepage collection drainage solid pipe 73. The geomembrane seepage collection drainage solid pipe 73 and the groundwater seepage collection drainage solid pipe 74 are connected to the water measuring weir.

[0033] The drainage slopes of the first drainage flower pipe 61 , the second drainage flower pipe 62 , the first drainage solid pipe 71 , the second drainage solid pipe 72 , the geomembrane seepage collection and drainage solid pipe 73 , and the groundwater seepage collection and drainage solid pipe 74 are all greater than 1%.

[0034] Whether the geomembrane 11 is damaged and the groundwater is rising can be determined based on the amount of water collected in the geomembrane seepage collection and drainage pipe 73 and the groundwater seepage collection and drainage pipe 74 that are led outside the reservoir.

[0035] According to the description and drawings of the present invention, those skilled in the art can easily manufacture or use the membrane-submerged drainage system for a face mask earth dam bank slope of the present invention, and can produce the positive effects described in the present invention.

[0036] It should be noted that the terms "including" and "having" in the specification and claims of the present invention and the above-mentioned drawings, as well as any variations thereof, are intended to cover non-exclusive inclusions. The terms "installed", "set", "provided with", "connected", "connected", and "socketed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be an internal connection between two mechanisms, elements, or components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0037] In the description of this utility model, it should be understood that terms such as "one end," "the other end," "outer side," "inner side," "horizontal," "end," "length," "outer end," "left," and "right" indicate positions or locations based on the positions or locations shown in the accompanying drawings. These terms are used solely to facilitate the description of this utility model and to simplify the description. They do not indicate or imply that the mechanisms or components referred to must have, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this utility model. The terms "first" and "second" are used solely for brevity of description and do not indicate or imply relative importance.

[0038] Furthermore, in practicing the claims of the present invention, those skilled in the art may understand and effect variations to the disclosed embodiments by studying the drawings, the disclosure, and the appended claims. Furthermore, in the claims and the specification, words such as "comprising" and "including" do not exclude other elements or steps, and non-plural nouns do not exclude their plural forms.

[0039] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of implementation of the present invention. All equivalent changes and modifications made based on the present invention are covered by the scope of the claims of the present invention and will not be listed one by one here.

Claims

1. A membrane-based drainage system for a face-film earth dam bank slope, comprising a geomembrane (11), characterized in that: The invention also includes a drainage mat (3) laid under the geomembrane (11), and a plurality of transverse ditches and longitudinal ditches are provided under the drainage mat (3). The bottom of the transverse ditches is connected to the groundwater level (10). The transverse ditches include a seepage collection ditch (5) provided along the foot of the bank slope and a plurality of first intercepting ditches (1) provided at different bank slope heights. The longitudinal ditches include a plurality of second intercepting ditches (2) provided along the bank slope direction. The plurality of second intercepting ditches (2) are connected between two adjacent transverse ditches. The side of the seepage collection ditch (5) away from the bank slope is connected to a reservoir bottom water diversion trough (12).

2. A membrane-based interception and drainage system for a face mask earth dam bank slope as claimed in claim 1, characterized in that: One end of the second intercepting ditch (2) is connected to the bottom of the first intercepting ditch (1) above it.

3. The membrane-submerged interception and drainage system for a face mask earth dam bank slope according to claim 1, characterized in that: Geotextiles (8) are laid on the inner walls of the reservoir bottom water diversion trough (12), the transverse water ditch and the longitudinal water ditch respectively. The first intercepting ditch (1) and the second intercepting ditch (2) are both filled with first graded crushed stone (91) and a first clay water barrier (41). The first clay water barrier (41) is located between the drainage mat (3) and the first graded crushed stone (91). The seepage water collection ditch (5) is filled with second graded crushed stone (92). The second graded crushed stone (92) is in contact with the lower surface of the drainage mat (3). A second clay water barrier (42) is provided on the side of the seepage water collection ditch (5) away from the bank slope. The second clay water barrier (42) is in contact with the lower surface of the geomembrane (11). The reservoir bottom water diversion trough (12) is filled with a third clay water barrier (43). The third clay water barrier (43) is in contact with the lower surface of the geomembrane (11).

4. The membrane-submerged interception and drainage system for a face mask earth dam bank slope according to claim 1, characterized in that: A first drainage flower pipe (61) is provided at the bottom of a plurality of the second intercepting ditches (2) near the foot of the bank slope, the outlet end of the first drainage flower pipe (61) is connected to a first drainage solid pipe (71), one end of the first drainage solid pipe (71) extends to the bottom of the seepage water collecting ditch (5), the bottom of the seepage water collecting ditch (5) is provided with a second drainage solid pipe (72) arranged along the length direction thereof, and the first drainage solid pipe (71) is connected to the second drainage solid pipe (72).

5. The membrane-submerged interception and drainage system for a face mask earth dam bank slope as claimed in claim 4, characterized in that: The bottom of the seepage water collecting ditch (5) is provided with a second drainage flower pipe (62) arranged along its length direction for collecting water seepage through the membrane.

6. A membrane-based interception and drainage system for a face mask earth dam bank slope as claimed in claim 5, characterized in that: A geomembrane seepage collection and drainage pipe (73) and a groundwater seepage collection and drainage pipe (74) are provided at the lower portion of the reservoir bottom water diversion trough (12) along its length, the outlet end of the second drainage flower pipe (62) is connected to the geomembrane seepage collection and drainage pipe (73), and the outlet end of the second drainage pipe (72) is connected to the groundwater seepage collection and drainage pipe (74).

7. A membrane-based interception and drainage system for a face mask earth dam bank slope as claimed in claim 6, characterized in that: The drainage slopes of the first drainage flower pipe (61), the second drainage flower pipe (62), the first drainage solid pipe (71), the second drainage solid pipe (72), the geomembrane seepage collection drainage solid pipe (73), and the groundwater seepage collection drainage solid pipe (74) are all greater than 1%.

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