Dam back seepage monitoring drainage structure capable of being rapidly constructed

Abstract

The utility model discloses a dam back seepage monitoring drainage structure capable of being quickly constructed, which relates to the field of hydropower and hydraulic engineering, and comprises a channel, a dam, a dam drainage body and a pressure slope body, and further comprises a concrete connector, an impermeable layer, a measuring weir retaining wall and a permeable drainage channel, the lower portion of the permeable drainage channel penetrates into the relative impervious layer, the impervious layer is laid from the top of the dam drainage body slope to the downstream along the channel, the downstream is embedded into the measuring weir retaining wall, the two sides are embedded into the concrete connecting body, the permeable drainage channel is arranged below the impervious layer and arranged along the bottom of the channel, the upstream of the permeable drainage channel is connected with the dam drainage body, and the downstream of the permeable drainage channel reaches the front of the measuring weir retaining wall. The pressure slope body is filled above the impermeable layer and is filled along the channel, the upstream of the pressure slope body leans on the back of the dam, and the downstream slope toe reaches the front of the retaining wall of the measuring weir. A relatively closed anti-seepage structure is defined by combining the anti-seepage layer, the concrete connecting body and the relatively impervious layer, dam seepage and pressure slope seepage are separated, and the seepage flow of the dam can be accurately monitored; the measuring weir retaining wall structure can respectively monitor seepage of the pressure slope body and seepage of the dam, and the stability of the pressure slope body and the stability of the dam can be respectively evaluated.

Description

Technical Field

[0001] The utility model relates to the field of hydropower and water conservancy projects, and particularly relates to a dam-back seepage monitoring and drainage structure that can be quickly constructed. Background Art

[0002] As an efficient power peak regulation, frequency modulation and energy storage facility, the pumped-storage power station has the advantages of high flexibility, fast response speed, long service life, etc., and is widely used in the power system. It stores water in the high-level reservoir during the low power demand period and releases the water flow to generate electricity during the high power demand period, so as to realize the reasonable allocation and balance of electric power. As a large global energy-consuming country, China has a particularly urgent demand for pumped-storage power stations.

[0003] During the construction process of pumped-storage power station projects, a large amount of earthwork excavation and backfilling are involved, and the amount of engineering waste is huge. Due to the increasing requirements for water and soil conservation, the site selection and approval of waste dumps have become increasingly difficult, and the problem of waste disposal has become the key point restricting the project progress. To avoid water and soil conservation risks, for reservoir projects with rolled earth-rock dams, most projects choose to store the waste behind the dam as a slope compaction body and fill it synchronously with the dam when conditions permit. Since the back-dam slope compaction body occupies the back-foot of the dam slope, the seepage of the dam body will converge at the toe of the dam slope, and then converge with the infiltration flow of the back-dam slope compaction body, and finally flow out from the toe of the back-dam slope compaction body. At this time, the outflow is quite different from the seepage flow of the dam, which is not convenient for monitoring the seepage of the dam.

[0004] To solve this problem, some projects choose to bury steel pipes at the bottom to lead the seepage water from the back-dam retaining wall to the toe of the back-dam slope compaction body, but there are problems of blockage and difficult maintenance; some other projects choose to bury box culverts at the lower part of the back-dam slope compaction body, with one end connected to the drainage holes of the retaining wall at the toe of the dam slope and the other end connected to the weir at the toe of the back-dam slope compaction body. The seepage of the dam and the seepage of the slope compaction body are separated and only flow out from the lower box culvert, so that the seepage flow of the dam can be accurately monitored; however, to ensure that the box culvert will not be damaged during the stacking process of the slope compaction body, the bottom of the box culvert needs to stand on stable bedrock. Considering that the box culvert is generally laid along the bottom of the ditch and the overburden layer at the bottom of the ditch is relatively deep, large-scale excavation is required during the construction of the box culvert, and most of them use cast-in-place reinforced concrete structures, which require dry construction conditions and need to be diverted. The construction is difficult and time-consuming, which greatly affects the normal slag stacking of the upper slope compaction body. The waste needs to be transferred and stacked, which greatly increases the waste disposal cost and the construction organization difficulty. Content of the Utility Model

[0005] In order to solve the above problems, the utility model provides a dam-back seepage monitoring and drainage structure that can be quickly constructed, which can effectively solve the problems of large seepage monitoring errors, difficult construction and long construction time in the prior art.

[0006] The utility model is realized through the following technical solutions.

[0007] A seepage monitoring and drainage structure behind a dam that can be quickly constructed, comprising a channel, a dam, a dam drainage body and a slope embankment, and further comprising a concrete connector, an anti-seepage layer, a weir retaining wall and a drainage channel. The concrete connector is arranged along the two banks of the channel in a full-length manner, and its lower part penetrates into the relatively impermeable layer. The anti-seepage layer is laid downstream along the channel from the top of the slope of the dam drainage body, and is embedded into the weir retaining wall downstream and into the concrete connector on both sides. The drainage channel is arranged below the anti-seepage layer and along the bottom of the channel. Its upstream is connected to the dam drainage body, and its downstream reaches in front of the weir retaining wall to lead the seepage of the dam to the weir retaining wall to monitor the seepage flow of the dam. The slope embankment is filled above the anti-seepage layer and along the channel. Its upstream relies on the back of the dam, and its downstream toe reaches in front of the weir retaining wall to lead the seepage of the slope embankment to the weir retaining wall to monitor the seepage flow of the slope embankment.

[0008] Further, the anti-seepage layer adopts a geomembrane and is laid in a corrugated shape.

[0009] Further, the weir retaining wall is composed of a retaining wall, a trough, drainage holes, an outflow trough, a measuring trough and an erosion-resistant bottom slab. The retaining wall is a gravity structure, and its bottom foundation and both ends reach the relatively impermeable layer. The trough is opened in the upper part of the retaining wall, and the drainage holes are opened in the lower part of the retaining wall. The bottom elevation of the trough is higher than the elevation of the geomembrane embedded in the retaining wall. The drainage holes are arranged in multiple layers in a staggered manner, and the drainage holes at the top layer are located below the elevation of the geomembrane embedded in the retaining wall. The measuring trough is composed of a flared water collecting section and a straight measuring section. The bottom elevation of the flared water collecting section is located below the drainage holes at the bottom layer of the retaining wall. The outflow trough is connected to the trough and extends to the outside of the flared water collecting section. Both the outflow trough and the measuring trough flow onto the erosion-resistant bottom slab. The erosion-resistant bottom slab is arranged along the natural terrain of the bottom of the channel, with the middle being low and both sides being high, and is smoothly connected to the existing channel.

[0010] Further, the following are sequentially laid upward in the drainage channel: a lower transition material layer, a lower cushion layer, a geomembrane, an upper cushion layer, and an upper transition material layer. The slope embankment is filled on the top of the upper transition material layer. Both the upper cushion layer and the lower cushion layer adopt gravel materials, and both the lower transition material layer and the upper transition material layer adopt crushed stone materials.

[0011] Further, when the relatively impermeable layer of the channel is relatively deep, a first lower transition material and a first lower cushion layer are filled at the bottom, a first geomembrane is laid, a first upper cushion layer and a first upper transition material layer are sequentially filled, and then the drainage channel and the upper lower transition material layer and lower cushion layer are filled. The first geomembrane at the bottom is welded to the geomembrane at the upper part, and then the upper upper cushion layer and upper transition material layer are filled.

[0012] Further, the first geomembrane is laid flat. Both the first upper cushion layer and the first lower cushion layer adopt gravel materials, and both the first lower transition material layer and the first upper transition material layer adopt crushed stone materials.

[0013] Furthermore, the permeable drainage channel is formed by piling up slightly weathered boulders.

[0014] Furthermore, when the flow rate of the channel is large, the upper part of the permeable drainage channel bulges into an arch shape.

[0015] The beneficial effects of the present utility model are as follows:

[0016] A relatively closed anti-seepage structure is formed by enclosing the anti-seepage layer, the concrete connector and the relatively impermeable layer, separating the seepage of the dam from the seepage of the slope protection body, and the seepage flow rate of the dam can be accurately monitored; the permeable drainage channel formed by excavating and filling the bottom of the trench can drain the upstream water during the construction period and the seepage water of the dam in the later stage, without the need to set up another diversion measure, the drainage structure is simple, the construction is convenient and fast, and the cost is low; the drainage holes arranged in layers and the water measuring weir retaining wall structure with water measuring function can monitor the seepage of the slope protection body in the upper part and the seepage of the dam in the lower part, the functions are concentrated, the layout is intensive, and it is convenient to evaluate the stability of the slope protection body and the dam respectively. Through this drainage structure, the problems of large seepage monitoring error, difficult construction and long time in the prior art can be effectively solved. Description of the Drawings

[0017] Figure 1 is the plan layout drawing of the post-dam seepage monitoring and drainage structure of the present utility model;

[0018] Figure 2 is the longitudinal sectional drawing of the post-dam seepage monitoring and drainage structure of the present utility model;

[0019] Figure 3 is the longitudinal sectional drawing of the water measuring weir retaining wall structure of the present utility model;

[0020] Figure 4 is the plan layout drawing of the water measuring weir retaining wall of the present utility model;

[0021] Figure 5 is the front view of the water measuring weir retaining wall of the present utility model;

[0022] Figure 6 is the cross-sectional drawing of the post-dam seepage monitoring and drainage structure in Embodiment 1;

[0023] Figure 7 is the cross-sectional drawing of the post-dam seepage monitoring and drainage structure in Embodiment 2;

[0024] Figure 8 is the cross-sectional drawing of the post-dam seepage monitoring and drainage structure in Embodiment 3;

[0025] Figure 9 is the cross-sectional drawing of the post-dam seepage monitoring and drainage structure in Embodiment 4.

[0026] In the figures:

[0027] 1 - Drainage channel, 2 - Lower transition material, 3 - Lower cushion layer, 4 - Geomembrane, 5 - Upper cushion layer, 6 - Upper transition material, 7 - Weir retaining wall, 8 - Concrete connection body, 701 - Retaining wall, 702 - Groove, 703 - Drainage hole, 704 - Outflow trough, 705 - Flume, 706 - Erosion-resistant bottom slab, 7051 - Bellmouth water-collecting section, 7052 - Straight flume section, 21 - First lower transition material, 31 - First lower cushion layer, 41 - First geomembrane, 51 - First upper cushion layer, 61 - First upper transition material, 9 - Dam, 10 - Dam drainage body, 11 - Slope protection body, 12 - Channel, 13 - Relatively impermeable layer. Detailed implementation mode

[0028] The following further explains the structures involved in the present invention or the technical terms used herein. These explanations are only examples to illustrate how the present invention is implemented and shall not constitute any limitation to the present invention.

[0029] In the description of the present invention, it should be understood that the orientation or positional relationships indicated by terms such as "upper", "lower", "front", "rear", "left" and "right" are based on the orientation or positional relationships shown in the drawings. These are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the indicated positions or elements must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of the present invention. In addition, terms such as "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0030] In the description of the present invention, unless otherwise clearly defined and limited, terms such as "connection" and "fixation" should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or integrated; it can be a direct connection or an indirect connection through an intermediate medium. It can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0031] Embodiment 1

[0032] As Figures 1 to 6As shown in the figure, when the channel is relatively shallow relative to the impervious layer 13 and the channel flow is small, a dam-back seepage monitoring and drainage structure that can be quickly constructed includes a channel 12, a dam 9, a dam drainage body 10, a slope protection body 11, a drainage channel 1, a lower transition material 2, a lower cushion layer 3, a geomembrane 4, an upper cushion layer 5, an upper transition material 6, a weir retaining wall 7, and a concrete connection body 8. The drainage channel 1 is formed by piling up slightly weathered boulders and is arranged along the bottom of the channel where the overburden has been excavated. Its upstream is connected to the dam drainage body 10, and its downstream extends to in front of the weir retaining wall 7. The lower transition material 2, the lower cushion layer 3, the geomembrane 4, the upper cushion layer 5, and the upper transition material 6 are successively filled or laid in layers upward from the drainage channel 1. The slope protection body 11 (waste slag) is filled on the upper part of the upper transition material 6. Both the upper cushion layer 5 and the lower cushion layer 3 are made of gravel to protect the geomembrane 4 from being punctured by gravel; both the lower transition material 2 and the upper transition material 6 are made of crushed stone to protect the upper cushion layer 5 and the lower cushion layer 3 from being washed away by flowing water; the slope protection body 11 is filled along the channel 12, with its upstream relying on the back of the dam and its downstream slope toe extending to in front of the weir retaining wall 7.

[0033] Among them, the dam drainage body 10 is arranged at the downstream bottom of the dam 9, and its main function is to drain the seepage water flowing from the upstream to the downstream and enhance the stability of the downstream dam slope.

[0034] The geomembrane 4 is located between the lower cushion layer 3 and the upper cushion layer 5, and is laid in a wave shape downward along the channel 12 from the top of the slope of the dam drainage body 10 to the downstream. The downstream end is embedded in the weir retaining wall 7, and both sides are embedded in the concrete connection body 8; the cross-section of the concrete connection body 8 is quadrilateral and is arranged along the two banks of the channel 12 in a full-length manner. Its lower part penetrates into the relatively impervious layer 13 and forms a relatively closed anti-seepage structure with the geomembrane 4 embedded on the side.

[0035] The weir retaining wall 7 is a concrete structure and is set at the slope toe of the slope protection body 11. It is composed of a retaining wall 701, a groove 702, drainage holes 703, an outflow groove 704, a water measuring trough 705, and an erosion-resistant bottom plate 706. Among them, the retaining wall 701 is a gravity structure, and its bottom foundation and both ends reach the relatively impervious layer 13. A groove 702 is opened in its upper part, and drainage holes 703 are opened in its lower part. The bottom elevation of the groove 702 is higher than the elevation of the geomembrane 4 embedded in the retaining wall. The drainage holes 703 are arranged in multiple layers in a staggered manner, and the top drainage holes 703 are located below the elevation of the geomembrane 4 embedded in the retaining wall 701; the water measuring trough 705 is composed of a flared water collecting section 7051 and a straight water measuring section 7052, and the bottom elevation of the flared water collecting section 7051 is located below the bottom drainage holes 703 of the retaining wall 701; the outflow groove 704 is connected to the groove 702 and extends to the outside of the flared water collecting section 7051; both the outflow groove 704 and the water measuring trough 705 flow onto the erosion-resistant bottom plate 706. The erosion-resistant bottom plate 706 is arranged along the natural terrain of the channel bottom, with the middle low and both sides high, and is smoothly connected to the existing channel.

[0036] The seepage of the dam is collected at the dam drainage body 11, flows through the drainage channel 1 to the water measuring weir retaining wall 7, and then flows out to the water measuring groove 705 through the drainage hole 703. After the flow rate is monitored in the straight water measuring section 7052, it is connected to the anti-scouring bottom plate 706 to the existing channel. The seepage of the pressure slope body is collected at its slope foot, that is, the upper part of the water measuring weir retaining wall 7. The flow rate is monitored when flowing through the groove 702, and then it is connected to the anti-scouring bottom plate 706 through the outflow groove 704 and flows into the existing channel.

[0037] Example 2

[0038] like Figure 7 As shown, when the channel is shallower than the impermeable layer 13 and the channel flow is larger, the upper part of the drainage channel 1 is raised in an arched shape to increase the water flow section. The rest is consistent with the first embodiment.

[0039] Example 3

[0040] like Figure 8 As shown, when the channel is deeper than the impermeable layer 13 and the channel flow is small, after the channel bottom is cleared and leveled, the first lower transition material 21 and the first lower cushion layer 31 are filled at the bottom, the first geomembrane 41 is laid, and the first upper cushion layer 51 and the first upper transition material 61 are filled in sequence, and then the drainage channel 1 and the upper lower transition material 2 and lower cushion layer 3 are filled, the first geomembrane 41 at the bottom and the upper geomembrane 4 are welded together, and then the upper cushion layer 5 and the upper transition material 6 are filled.

[0041] The first geomembrane 41 is laid straightly, and the first upper cushion layer 51 and the first lower cushion layer 31 are both made of gravel to protect the first geomembrane 41 from being punctured by gravel; the first lower transition material 21 and the first upper transition material 61 are both made of crushed stone to protect the first upper cushion layer 51 and the first lower cushion layer 31 from being carried away by flowing water.

[0042] Example 4

[0043] like Figure 9 As shown, when the channel is deeper than the impermeable layer 13 and the channel flow is larger, the upper part of the drainage channel 1 is raised in an arched shape to increase the water flow section.

[0044] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to replace some of the technical features therein with equivalents. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A rapidly constructed post-dam seepage monitoring and drainage structure, comprising a ditch, a dam, a dam drainage body and a slope pressure body, characterized in that: It also includes a concrete connector, an anti-seepage layer, a water-measuring weir retaining wall and a permeable drainage channel. The concrete connector is arranged along both sides of the channel, and its lower part penetrates into a relatively impermeable layer. The anti-seepage layer is laid from the top of the slope of the dam drainage body along the channel to the downstream, and is embedded in the water-measuring weir retaining wall downstream and in the concrete connector on both sides. The permeable drainage channel is set below the anti-seepage layer and arranged along the bottom of the channel. Its upstream is connected to the dam drainage body and its downstream is in front of the water-measuring weir retaining wall. The dam seepage is led to the water-measuring weir retaining wall to monitor the dam seepage volume; the pressure slope body is filled above the anti-seepage layer and filled along the channel. Its upstream is close to the dam and its downstream slope foot is in front of the water-measuring weir retaining wall. The pressure slope body seepage is led to the water-measuring weir retaining wall to monitor the pressure slope body seepage volume.

2. The rapidly constructable post-dam seepage monitoring and drainage structure according to claim 1 is characterized in that: The anti-seepage layer adopts geomembrane and is laid in a corrugated shape.

3. The rapidly constructable post-dam seepage monitoring and drainage structure according to claim 2 is characterized in that: The water measuring weir retaining wall is composed of a retaining wall, a groove, a drainage hole, an outflow trough, a water measuring trough and an anti-scouring bottom plate. The retaining wall is a gravity structure, and the bottom foundation and both ends are relatively impermeable layers. The groove is opened in the upper part of the retaining wall, and the drainage hole is opened in the lower part of the retaining wall. The bottom elevation of the groove is higher than the elevation of the geomembrane embedded in the retaining wall. The drainage holes are arranged in multiple layers in an alternating manner, and the drainage holes on the top layer are located below the elevation of the geomembrane embedded in the retaining wall; the water measuring trough is composed of a bell-mouth water collection section and a straight water measuring section, and the bottom elevation of the bell-mouth water collection section is located below the drainage holes on the bottom layer of the retaining wall; the outflow trough is connected with the groove and extends to the outside of the bell-mouth water collection section; the outflow trough and the water measuring trough both flow to the anti-scouring bottom plate, and the anti-scouring bottom plate is arranged along the natural terrain of the bottom of the channel, with a low middle and high sides, and connected to the existing channel.

4. The rapidly constructable post-dam seepage monitoring and drainage structure according to claim 2 is characterized in that: The drainage channel is paved with lower transition material, lower cushion layer, geomembrane, upper cushion layer and upper transition material in sequence, and the slope pressure body is filled on the top of the upper transition material. The upper cushion layer and the lower cushion layer are both made of gravel, and the lower transition material and the upper transition material are both made of crushed stone.

5. The rapidly constructable post-dam seepage monitoring and drainage structure according to claim 4 is characterized in that: The permeable drainage channel is formed by the accumulation of slightly weathered blocks of stone.

6. The rapidly constructable post-dam seepage monitoring and drainage structure according to claim 5 is characterized by: When the channel flow is relatively large, the upper portion of the drainage channel is raised in an arch shape.

Images