Open-cast stope adjacent seasonal water source slope anti-permeation system
By setting up water-retaining structures and drainage pipeline systems in the open-pit mine, the hydraulic connection between the seasonal lake and the slope is blocked, thus solving the problem of the seasonal lake's permeability affecting slope stability and improving slope stability and mining safety.
Patent Information
- Application Number
- CN202423313525.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-31
- Publication Date
- 2025-12-23
- Estimated Expiration
- 2034-12-31
AI Technical Summary
When an open-pit mine passes through a seasonal lake, the lake's high water permeability reduces slope stability and affects mine safety.
The system employs water-blocking structures and drainage pipe systems, including water-stop curtains, gravity or pressurized drainage pipes, to block hydraulic connections and discharge lake water, preventing seepage.
It effectively prevents lake water from seeping into the slope, improves slope stability, reduces mining risks, shortens the time spent traversing seasonal lakes, and lowers costs.
Smart Images
Figure CN223706419U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the technical field, in particular to a seepage prevention system for slopes near seasonal water sources in open-pit mines. Background Technology
[0002] Seasonal lakes are affected by seasons and weather. Their water mainly comes from precipitation and runoff from surrounding strata. After being filled, they form surface water bodies. The lake water is mainly discharged through evaporation or infiltration. When an open-pit mine passes through a seasonal lake during construction, and the lake happens to be in its water storage period, the lake water seeps into the mine slope due to the good permeability of the loess and coarse sandstone on the shallow slope. This increases the water content of the rock strata and reduces the stability of the slope. Summary of the Invention
[0003] Purpose of the invention: In order to overcome the shortcomings of the existing technology, this utility model provides a seepage prevention system for slopes near seasonal water sources in open-pit mines, which can solve the problem of slope stability being affected by water seepage when the mine passes through seasonal lakes.
[0004] Technical Solution: To achieve the above objectives, the present invention provides an anti-seepage system for slopes adjacent to seasonal water sources in open-pit mines, comprising a water-retaining structure and a drainage pipeline. The water-retaining structure is located between the seasonal water source and the near-water slope of the mine. The first end of the drainage pipeline is located at the bottom of the seasonal water source, and the second end of the drainage pipeline extends away from the surface catchment area of the seasonal water source. The water-retaining structure is used to sever the hydraulic connection between the seasonal water source and the near-water slope during the water storage period, or to increase the distance between the near-water slope and the seasonal water source during the water storage period.
[0005] Furthermore, the drainage pipeline is a gravity drainage pipeline, including an inclined water channel that spans across the bottom of the seasonal water source, and an inclined water pipe connected to the lower end of the inclined water channel.
[0006] Furthermore, the drainage pipeline is a pressurized drainage pipeline, including a submersible drainage pump located at the bottom of the seasonal water source, and the pressurized drainage pipeline is buried at a fixed depth along the terrain.
[0007] Furthermore, the water-blocking structure is a water-stop curtain made of low-permeability material, which is vertically buried in the stratum between the seasonal water source and the near-water slope, with the lower end of the water-stop curtain buried in the relative water-proof layer of the stratum.
[0008] Furthermore, the water-retaining structure is a reserved water-retaining strip, which is a section of fixed width extending from the water level line of the seasonal water source towards the near-water slope.
[0009] Furthermore, the near-water slope starts from the edge of the reserved water-retaining strip away from the seasonal water source, and slopes downwards with a stepped end slope structure. Multiple steps at the bottom of the near-water slope are reserved to provide safety platforms.
[0010] Beneficial effects: The seepage prevention system for slopes near seasonal water sources in open-pit mines of this utility model prevents lake water from seeping into the slope and affecting the stability of the mine slope by setting up water-blocking structures to block or delay the contact between the underground flow field and the flow field and the slope, and by cooperating with drainage pipes to discharge seasonal lake water. Attached Figure Description
[0011] Figure 1 A schematic diagram of the combined system of water-stop curtain and gravity drainage pipe;
[0012] Figure 2 This is a schematic diagram of the combined system of a water-resistant strip and a pressurized drainage pipe. Detailed Implementation
[0013] The present invention will be further described below with reference to the accompanying drawings.
[0014] As attached Figure 1-2 The aforementioned seepage prevention system for slopes adjacent to seasonal water sources in open-pit mines includes a water-retaining structure 1 and a drainage pipe 2. The water-retaining structure 1 is located between a seasonal water source 3 and a water-prone slope 4 of the mine. The first end of the drainage pipe 2 is located at the bottom of the seasonal water source 3, and the second end extends away from the surface catchment area of the seasonal water source 3. The water-retaining structure 1 is used to isolate the hydraulic connection between the seasonal water source 3 and the water-prone slope 4 during the water storage period, or to increase the distance between the water-prone slope 4 and the seasonal water source 3 during the water storage period. The seasonal water source is a seasonal lake near the mine, and the excavated slope of the mine continuously approaches this seasonal lake. When the seasonal lake is filled with water, a flow field is formed outward from the water body. By setting up a water-blocking structure 1 to block or delay the contact between the underground flow field and the slope, and in conjunction with the drainage pipe 2 to discharge the water stored in the seasonal lake, the surface water flowing into the lake can be discharged in time during the rainy season, ensuring that there is no water in the lake, thereby preventing the lake water from overflowing or seeping into the slope and affecting the stability of the mine slope.
[0015] The drainage pipe 2 is either a gravity drainage pipe or a pressurized drainage pipe. When the drainage pipe 2 is a gravity drainage pipe, it includes an inclined water channel that spans across the bottom of the seasonal water source 3 and an inclined water pipe connected to the lower end of the inclined water channel. When the drainage pipe 2 is a pressurized drainage pipe, it includes a submersible drainage pump located at the bottom of the seasonal water source 3, and the pressurized drainage pipe is buried at a fixed depth along the terrain.
[0016] Where the terrain slopes downwards along the drainage pipeline route, gravity drainage pipes are used. Both the inclined channels and pipes are constructed with cement, utilizing the slope for drainage. This ensures the overall drainage pipeline slopes downwards, and as much of it as possible is constructed as open channels to minimize excavation depth. Where the terrain undulates along the drainage pipeline route, pressure pipes are used. These pressure pipes are made of PE pipe and are excavated and buried along the undulating terrain. The top of the pipe is covered with 0.7m of soil, significantly reducing excavation and protecting the PE pipe from erosion and damage.
[0017] Preferably, when the terrain is undulating in the drainage direction, gravity drainage open channels are used in sections from high to low, buried gravity drainage pipes are used in sections with a gentler slope from low to high, and buried pressure pipes are used in sections with a steeper slope from low to high. A water pump is installed at the beginning of the pressure pipe connected to the rear of the gravity pipe, thereby minimizing costs and reducing the depth of earthwork excavation.
[0018] When the drainage direction extends into populated areas, such as the transport road area of a mine, except for the section of pipes crossing the transport road which must be buried, the remaining gravity drainage pipes can be set up as open channels, while the pressure drainage pipes are left exposed. A water storage tank (6) should be installed in low-lying areas to prevent drainage from accumulating and flooding the transport road during heavy rainfall. If the drainage direction is to an uninhabited area, pressurized drainage pipes can be directly selected and laid exposed at a certain distance from the slope, allowing for easy relocation outwards as the mine pit is excavated.
[0019] The water-blocking structure 1 is a water-stop curtain or a reserved water-proof strip;
[0020] When the water-retaining structure 1 is a water-stop curtain made of low-permeability material, the water-stop curtain is vertically buried in the stratum between the seasonal water source 3 and the near-water slope 4, with the lower end of the water-stop curtain embedded in the corresponding water-impermeable layer of the stratum. Preferably, the water-stop curtain is cast with cement and is located on the water-side of the dam body between the surface water body and the mine pit slope. Mature construction techniques such as the TRD method or the CSM method can be selected for construction. On both sides of the water-stop curtain, a short section of wall is poured towards the water body to form an angle with the main body. This is used to avoid the slight flow around the water-stop curtain. The water-stop curtain plays a significant role in blocking the water body. Because its bottom is inserted into the low-permeability rock layer underground, the flow field cannot bypass the water-stop curtain. The water-stop curtain is set in a direction parallel to the slope, with the point closest to the center of the lake bottom as the center. Taking advantage of the seasonal characteristic that the flow velocity and flow rate of the lake field decrease as it is farther away from the center of the lake, it is ensured that the fluid velocity and flow rate reaching the edges of the water-stop curtain are very small and insufficient to penetrate the slope and affect its stability.
[0021] The water-stopping curtain is wider at the top and narrower at the bottom, so that both sides facing the seasonal lake and the slope are inclined. After being cast with cement, the cement curtain, under its own weight, compresses the rock layers on both sides, making the shallow loess and coarse sandstone layers more compact in the area near the water-stopping curtain. This further slows down the infiltration rate of water flow, while compressing and stabilizing the rock structure, further stabilizing the slope structure, making it less likely to cause fault landslides, and further ensuring the stability of the slope.
[0022] When the water-blocking structure 1 is a reserved water-proof strip, as shown in the attached... Figure 2 As shown, the reserved water-retaining zone is a section of fixed width extending from the water infiltration line 31 of the seasonal water source 3 towards the near-water slope 4. The near-water slope 4 starts at the edge of the reserved water-retaining zone away from the seasonal water source 3, and slopes downwards in a stepped end-slope structure at a 20° angle, forming a multi-level arc-shaped slope. This keeps the slope surface away from the water body, creating a sufficiently wide infiltration zone between the water body and the slope. The slope surface is located at the edge of the water flow field, where the flow velocity and flow rate are relatively low, minimizing the impact on slope stability. Multiple steps at the bottom of the near-water slope 4 are reserved as safety platforms. This allows the slope near the seasonal lake to bypass the lake during the water storage period, providing a sufficient buffer infiltration area between the near-water slope and the water body. This reduces the impact on the slope during the water storage period, delaying the stripping near the seasonal lake until the lake is no longer in the water storage period, thereby reducing the risk of slope instability.
[0023] In one example, when a mine in a certain area passes through a seasonal lake, a water-retaining zone approximately 60 meters wide is left outside the lake's waterline. This zone is then sloped downwards using a stepped end-slope structure, with safety platforms located at the bottom four steps. Mining and stripping near the seasonal lake are delayed by 7 months. From the 8th to the 29th month, the lake is crossed at a faster pace, achieving internal drainage and slope protection 7 months earlier. This shortens the time to cross the seasonal lake from the normal 36 months to 22 months. Since the rainy season in this area is in July and August, starting the removal of the water-retaining zone in September reduces the three rainy seasons of crossing the seasonal lake to one, lowering the risk by approximately two-thirds.
[0024] Considering the reliability issues caused by uncertainties such as economic benefits and geological structure, the preferred option is... Figure 2 The scheme shown combines gentle slope mining with bypassing and pressurized drainage into uninhabited areas.
[0025] The above are merely preferred embodiments of this utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this utility model, and these improvements and modifications should also be considered within the protection scope of this utility model.
Claims
1. A seepage prevention system for slopes adjacent to seasonal water sources in open-pit mines, characterized in that: The system includes a water-retaining structure (1) and a drainage pipe (2). The water-retaining structure (1) is located between the seasonal water source (3) and the near-water slope (4) of the mine. The first end of the drainage pipe (2) is located at the bottom of the seasonal water source (3), and the end of the drainage pipe (2) extends away from the surface catchment area of the seasonal water source (3). The water-retaining structure (1) is used to cut off the hydraulic connection between the seasonal water source (3) and the near-water slope (4) during the water storage period, or to increase the distance between the near-water slope (4) and the seasonal water source (3) during the water storage period.
2. The seepage prevention system for slopes adjacent to seasonal water sources in open-pit mines according to claim 1, characterized in that: The drainage pipe (2) is a gravity drainage pipe, including an inclined water channel that spans the bottom of the seasonal water source (3) and an inclined water pipe that connects to the lower end of the inclined water channel.
3. The seepage prevention system for slopes adjacent to seasonal water sources in open-pit mines according to claim 1, characterized in that: The drainage pipe (2) is a pressurized drainage pipe, including a submersible drainage pump located at the bottom of the seasonal water source (3), and the pressurized drainage pipe is buried at a fixed depth along the terrain.
4. The seepage prevention system for slopes adjacent to seasonal water sources in open-pit mines according to claim 1, characterized in that: The water-blocking structure (1) is a water-stop curtain made of low-permeability material. The water-stop curtain is vertically buried in the stratum between the seasonal water source (3) and the near-water slope (4). The lower end of the water-stop curtain is buried in the relative water-proof layer of the stratum.
5. The seepage prevention system for slopes adjacent to seasonal water sources in open-pit mines according to claim 1, characterized in that: The water-blocking structure (1) is a reserved water-blocking strip, which is a section of fixed width extending from the water infiltration line (31) of the seasonal water source (3) toward the near-water slope (4).
6. The seepage prevention system for slopes adjacent to seasonal water sources in open-pit mines according to claim 5, characterized in that: The near-water slope (4) starts from the edge of the reserved water barrier away from the seasonal water source (3) and slopes downward with the end slope step structure. Multiple steps at the bottom of the near-water slope (4) are reserved to provide a safety platform (5).