Slope supporting structure for water level amplitude variation area of pumped storage power station

Abstract

The utility model relates to a side slope supporting structure for a water level amplitude variation area of a pumped storage power station, and belongs to the technical field of side slope supporting structures in hydropower and hydraulic engineering. The structure comprises a reservoir, the reservoir is provided with a water level variable amplitude area located on a rock mass side slope, a water collecting gallery is correspondingly arranged in the rock mass side slope in the water level variable amplitude area along the trend of a reservoir side line of the reservoir, and a construction vertical shaft communicated with an external atmosphere is arranged at the top of the water collecting gallery. A drainage pipe communicated with the reservoir is arranged at the top of the water collecting gallery, the water inlet end of the drainage pipe is close to the water collecting gallery, the drainage end of the drainage pipe is close to the reservoir, the water inlet end of the drainage pipe is not lower than the drainage end of the drainage pipe, and the lower edge of the drainage end of the drainage pipe is higher than the upper limit water level of the water level variable amplitude area; and a plurality of drainage pipes are arranged at intervals along the length direction of the water collecting gallery. The utility model is applicable to rock slope support of the water level amplitude variation area of the pumped storage power station, and improves the stability of the slope of the amplitude variation area.

Description

Technical Field

[0001] The utility model relates to a slope support structure in a water level variation zone of a pumped storage power station, belonging to the technical field of slope support structures in hydropower and water conservancy projects. Background Art

[0002] Pumped-storage power stations have become a hotspot for clean energy development in my country in recent years due to their mature technology, excellent economic efficiency, and ability to develop large-scale energy storage. Pumped-storage power stations use water as a storage medium. During periods of low grid load, excess electricity is used to pump water from the lower reservoir to the upper reservoir, converting the electricity into water potential energy. During peak grid load periods, water from the upper reservoir flows into the power plant to generate electricity, alleviating the pressure of peak power demand. Pumped-storage power stations are sensitive to the stability of the reservoir slopes, especially the water level fluctuation zone. The water level fluctuation zone should generally be excavated to the bedrock. When the bedrock conditions are good, additional support measures are generally not considered in the water level fluctuation zone. Therefore, current research on slope support structures in the water level fluctuation zone of pumped-storage power stations focuses on the overburden slope. For details, please refer to the applicant's prior patent application with publication number CN117107708A. However, in actual engineering, we often encounter situations where the bedrock strength and integrity do not meet the design requirements, that is, the bedrock strength and integrity are poor (generally referred to as inferior rock mass). At this time, appropriate support treatment is required. At present, no relevant research in this regard has been seen.

[0003] Poor-quality rock slopes are characterized by low strength, poor erosion resistance, a layered to mosaic structure, and susceptibility to delamination under external forces. When the water level within the reservoir fluctuates slightly, the shallow rock mass on the slope is in a transient state of stress equilibrium under the influence of the deep mountain and reservoir water. When the water level drops, the pressure differential between the deep mountain and reservoir water increases. The combined effects of the mountain water pressure and the unloading of the shallow rock mass cause the shallow rock mass to move toward the free surface of the slope within the reservoir. When the water level rises, the pressure differential between the deep mountain and reservoir water pressures decreases, causing the shallow rock mass to move toward the mountain. Frequent water level fluctuations can easily lead to fatigue failure of the shallow rock mass on the slope, leading to bank collapse and inrush into the reservoir, creating surge waves that overturn the dam and cause engineering accidents. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a slope support structure in the water level variation zone of a pumped storage power station, which can be applied to rock slope support and improve the stability of the slope in the variation zone.

[0005] In order to solve the above technical problems, the technical solution adopted by the utility model is: a slope support structure of the water level variation zone of a pumped storage power station, including a reservoir, the reservoir having a water level variation zone located on the rock slope, and a water collection gallery is arranged inside the rock slope along the reservoir edge line in the water level variation zone. A construction shaft connected to the external atmosphere is arranged on the top of the water collection gallery, and a drainage pipe connected to the reservoir is arranged on the top of the water collection gallery. The water inlet end of the drainage pipe is the end close to the water collection gallery, and the drainage end is the end close to the reservoir. The water inlet end of the drainage pipe is located at a position not lower than the drainage end of the drainage pipe, and the lower edge of the drainage end of the drainage pipe is located higher than the upper limit water level of the water level variation zone. Multiple drainage pipes are arranged at intervals along the length direction of the water collection gallery.

[0006] In order to improve the structural reliability, a further preferred solution is that the bottom elevation of the inner cavity of the water collection corridor is lower than the lower limit water level of the water level variation zone.

[0007] To facilitate implementation and improve structural reliability, a further preferred solution is that the cross-section of the water collection corridor is in the shape of a city gate, and the water inlet end of the drainage pipe is arranged at the top arch of the water collection corridor.

[0008] To facilitate implementation and improve structural reliability, a further preferred solution is: multiple groups of prefabricated linings are arranged at intervals along the length of the water collection corridor, and each group of prefabricated linings is composed of an arched prefabricated part and two L-shaped prefabricated parts to form a gate-shaped lining body. The ends of the two L-shaped prefabricated parts are connected by a first snap-fit ​​structure, and the first snap-fit ​​structure is located in the middle area of ​​the bottom plate of the water collection corridor. The two ends of the arched prefabricated part are respectively connected to the ends of the L-shaped prefabricated part through a second snap-fit ​​structure, and the second snap-fit ​​structure is located in the top area of ​​the straight side wall of the water collection corridor.

[0009] In order to improve the structural reliability, a further preferred solution is: articulated slope protection bricks are laid on the slope surface on the water side of the water level fluctuation zone, and the articulated slope protection bricks are anchored to the slope surface by anchor cables. The top edge of the articulated slope protection bricks is higher than the upper limit water level of the water level fluctuation zone, and the bottom edge of the articulated slope protection bricks is lower than the lower limit water level of the water level fluctuation zone.

[0010] To facilitate implementation and improve structural reliability, a further preferred solution is that the inner end of the anchor cable extends horizontally into the water collection gallery for anchoring.

[0011] The beneficial effects of the present invention are as follows: by setting up a water collection gallery, the groundwater seepage field is changed, and the groundwater in the deep mountain first flows into the water collection gallery, and the groundwater in the water collection gallery accumulates, the water level rises, and finally flows into the reservoir through the drainage pipe in the water collection gallery. The drainage pipe and the construction shaft in the water collection gallery are both connected to the external atmosphere, and the water pressure of the groundwater flowing into the water collection gallery can be sharply reduced, and the groundwater pressure has little effect on the external shallow surface rock mass; the rock mass in the deep mountain is unloaded under the action of the drop in reservoir water level, and has a tendency to deform preferentially in the water collection gallery, reducing the impact of the unloading of the deep mountain on the surface rock mass of the slope. In addition, in a preferred embodiment, the prefabricated lining and anchor cables can reinforce the internal surrounding rock of the water collection gallery and improve the stability of the surrounding rock. The articulated slope protection bricks are located on the shallow surface rock mass, and can also prevent the shallow surface rock mass of the slope from being washed away and damaged by reservoir water.

[0012] During operation, when the water level in the reservoir drops, the water pressure on the shallow rock mass decreases, while the water pressure in the mountain remains unchanged. The water pressure difference increases, causing groundwater in the mountain to drain into the reservoir and flow into the water collection corridor. The water collection corridor is connected to the external atmosphere, and the water pressure of the groundwater flowing into the water collection corridor decreases sharply, with the groundwater having little impact on the shallow rock mass. When the water level rises, the water pressure on the shallow rock mass increases, while the water pressure in the mountain remains unchanged. The water collection corridor acts like a "funnel," with reservoir water seeping into the water collection corridor through the shallow rock mass. Groundwater in the deep mountain rock mass continues to drain into the water collection corridor, causing the groundwater in the water collection corridor to accumulate, and the water level in the water collection corridor rises. The water is then discharged into the reservoir through the drainage pipe, reducing reservoir water leakage. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the plane layout of the present utility model.

[0014] Figure 2 for Figure 1 AA facade structure diagram in.

[0015] Figure 3 for Figure 1 Schematic diagram of the BB facade structure.

[0016] Figure 4 for Figure 1 Schematic diagram of CC facade structure.

[0017] Figure 5 This is a schematic diagram of the exploded structure of the prefabricated lining in the present invention.

[0018] Marked in the figure: water level fluctuation area 1, articulated slope protection bricks 2, anchor cables 3, water collection gallery 4, construction shaft 5, drainage pipe 6, precast lining 7, reservoir 8, dam 9. DETAILED DESCRIPTION

[0019] The present invention will be further described below with reference to the accompanying drawings.

[0020] like Figures 1 to 5 As shown, the present invention includes a reservoir 8 having a water level fluctuation zone 1 located on a rock mass slope. A water collection gallery 4 is arranged inside the rock mass slope along the reservoir edge line in the corresponding water level fluctuation zone 1. The water collection gallery 4 surrounds the reservoir 8 in a nearly annular structure. Generally, only the area where the dam 9 is located is not arranged. A construction shaft 5 connected to the external atmosphere is arranged on the top of the water collection gallery 4. A drainage pipe 6 connected to the reservoir 8 is arranged on the top of the water collection gallery 4. The water inlet end of the drainage pipe 6 is the end close to the water collection gallery 4, and the drainage end is the end close to the reservoir 8. The water inlet end of the drainage pipe 6 is located at a position not lower than the drainage end of the drainage pipe 6 (generally arranged at an angle, with the drainage end at the lower end). The lower edge of the drainage end of the drainage pipe 6 is located above the upper limit water level of the water level fluctuation zone 1. Multiple drainage pipes 6 are arranged at intervals along the length of the water collection gallery 4. Wherein the main function of the construction shaft 5 is to be used for the construction of the corridor structure, and one or more construction shafts can be arranged, and generally at least one is arranged respectively at the first and last ends. Because the construction shaft 5 is connected to the external atmosphere, it can also play the role of a ventilation well.

[0021] The design principle of this utility model is as follows: after the construction of the water collection gallery 4 is completed, the groundwater seepage field can be changed. The groundwater in the deep mountain body first flows into the water collection gallery 4, and the groundwater in the water collection gallery 4 accumulates, the water level rises, and finally flows into the reservoir 8 through the drainage pipe 6 in the water collection gallery 4. The drainage pipe 6 in the water collection gallery 4 and the construction shaft 5 are both connected to the external atmosphere. The water pressure of the groundwater flowing into the water collection gallery 4 can be sharply reduced, and the impact of the groundwater pressure on the external shallow surface rock mass is small; the rock mass in the deep mountain body is unloaded under the action of the lowering of the reservoir water level, and has a tendency to deform preferentially into the water collection gallery 4, reducing the impact of the deep mountain body unloading on the surface rock mass of the slope. During the operation of reservoir 8, when the water level in the reservoir drops, the water pressure of the reservoir water on the shallow rock mass decreases, the water pressure in the mountain remains unchanged, the water pressure difference increases, and the groundwater in the mountain is discharged into the reservoir 8 and flows into the water collection corridor 4. The water collection corridor 4 is connected to the external atmosphere. The water pressure of the groundwater flowing into the water collection corridor 4 decreases sharply, and the impact of the groundwater on the shallow rock mass is small. When the water level rises, the water pressure of the reservoir water on the shallow rock mass increases, the water pressure in the mountain remains unchanged, and the water collection corridor 4 is like a "funnel". The reservoir water seeps into the water collection corridor 4 through the shallow rock mass, while the groundwater in the deep rock mass in the mountain still flows into the water collection corridor 4. The groundwater in the water collection corridor 4 continues to accumulate, the water level in the water collection corridor 4 rises, and is discharged into the reservoir 8 through the drainage pipe 6, reducing the leakage of reservoir water.

[0022] The water collection corridor 4 is arranged in correspondence with the water level variation zone 1, which means that the projections of the two on the vertical plane at least partially overlap. Since the drainage pipe 6 is connected to the top of the water collection corridor 4, and the lower edge of the drainage end of the drainage pipe 6 is located higher than the upper limit water level of the water level variation zone 1, the top elevation of the water collection corridor 4 must be higher than the upper limit water level of the water level variation zone 1, and the elevation of the inner cavity bottom of the water collection corridor 4 should at least be lower than the upper limit water level of the water level variation zone 1. In order to improve the structural reliability, the preferred solution is that the elevation of the inner cavity bottom of the water collection corridor 4 is lower than the lower limit water level of the water level variation zone 1, so as to give full play to the role of the water collection corridor 4.

[0023] To facilitate implementation and improve structural reliability, a further preferred solution is: the cross-section of the water collection corridor 4 is in the shape of a city gate (i.e., a round arch straight wall shape), and the water inlet end of the drainage pipe 6 is arranged at the top arch of the water collection corridor 4 (slightly higher than the top of the straight wall section).

[0024] To facilitate implementation and improve structural reliability, a further preferred solution is as follows: multiple groups of precast linings 7 are arranged at intervals along the length of the water collection corridor 4. Each group of precast linings 7 is composed of an arched precast member and two L-shaped precast members, forming a main lining body in the shape of a city gate. The ends of the two L-shaped precast members are connected by a first snap-fit ​​structure, which is located in the middle area of ​​the bottom plate of the water collection corridor 4. The two ends of the arched precast member are connected to the ends of the L-shaped precast member through a second snap-fit ​​structure, which is located in the top area of ​​the straight side wall of the water collection corridor 4. By adding precast linings 7, the stability of the water collection corridor 4 can be improved and collapse within the tunnel can be avoided. The precast lining 7 adopts a prefabricated assembled structure, which is convenient for construction. Specifically, the first snap-fit ​​structure and the second snap-fit ​​structure can adopt conventional L-shaped joints or T-shaped joints (the first snap-fit ​​structure and the second snap-fit ​​structure can be designed to be the same or different). The first snap-fit ​​structure and the second snap-fit ​​structure of the embodiment shown in the figure both adopt L-shaped joints.

[0025] To improve structural reliability, a further preferred solution is to lay articulated slope protection bricks 2 on the water-facing slope of the water-level fluctuation zone 1. These are anchored to the slope by anchor cables 3. The top edge of these articulated slope protection bricks 2 is higher than the upper limit water level of the water-level fluctuation zone 1, while the bottom edge of these articulated slope protection bricks 2 is lower than the lower limit water level of the water-level fluctuation zone 1. This "anchor cables 3 + articulated slope protection bricks 2" structure improves the stability of the rock mass on the water-facing side.

[0026] To facilitate implementation and improve structural reliability, a further preferred solution is to extend the inner ends of the anchor cables 3 horizontally into the water collection corridor 4 for anchoring. Typically, the inner ends of the anchor cables 3 are preferably positioned in the middle of the precast lining 7 to better apply prestress to the rock mass. Generally, unless there are special circumstances, the anchor cables 3 are arranged at equal intervals. Only when encountering faults or fracture zones is it necessary to arrange the precast lining 7 and anchor cables 3 separately.

Claims

1. A slope support structure for a water level variation zone of a pumped storage power station, comprising a reservoir (8), wherein the reservoir (8) has a water level variation zone (1) located on a rock mass slope, and wherein: A water collection gallery (4) is arranged inside the rock mass slope along the reservoir edge line of the reservoir (8) in the water level variation zone (1), a construction shaft (5) connected to the external atmosphere is arranged on the top of the water collection gallery (4), a drainage pipe (6) connected to the reservoir (8) is arranged on the top of the water collection gallery (4), the water inlet end of the drainage pipe (6) is the end close to the water collection gallery (4), and the drainage end is the end close to the reservoir (8), the water inlet end of the drainage pipe (6) is located at a position not lower than the drainage end of the drainage pipe (6), the lower edge of the drainage end of the drainage pipe (6) is located at a position higher than the upper limit water level of the water level variation zone (1), and a plurality of drainage pipes (6) are arranged at intervals along the length direction of the water collection gallery (4).

2. The slope support structure in the water level variation area of ​​a pumped storage power station according to claim 1, characterized in that: The elevation of the inner cavity bottom of the water collection gallery (4) is lower than the lower limit water level of the water level variation zone (1).

3. The slope support structure in the water level variation area of ​​a pumped storage power station according to claim 1, characterized in that: The cross section of the water collection gallery (4) is in the shape of a city gate, and the water inlet end of the drainage pipe (6) is arranged at the top arch of the water collection gallery (4).

4. The slope support structure in the water level variation area of ​​a pumped storage power station according to claim 3, characterized in that: A plurality of groups of prefabricated linings (7) are arranged at intervals along the length direction of the water collection gallery (4). Each group of prefabricated linings (7) is composed of an arched prefabricated component and two L-shaped prefabricated components to form a main lining body in the shape of a city gate. The ends of the two L-shaped prefabricated components are butted together via a first snap-fit ​​structure, which is located in the middle area of ​​the bottom plate of the water collection gallery (4). The two ends of the arched prefabricated component are respectively butted together with the ends of the L-shaped prefabricated component via a second snap-fit ​​structure, which is located in the top area of ​​the straight side wall of the water collection gallery (4).

5. The slope support structure in the water level variation area of ​​a pumped storage power station according to any one of claims 1 to 4, characterized in that: The water level fluctuation zone (1) is provided with an articulated slope protection brick (2) on the slope surface on the water-facing side thereof. The articulated slope protection brick (2) is anchored on the slope surface by an anchor cable (3). The top edge of the articulated slope protection brick (2) is higher than the upper limit water level of the water level fluctuation zone (1), and the bottom edge of the articulated slope protection brick (2) is lower than the lower limit water level of the water level fluctuation zone (1).

6. The slope support structure in the water level variation area of ​​a pumped storage power station according to claim 5, characterized in that: The inner end of the anchor cable (3) extends horizontally into the water collection gallery (4) for anchoring.

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