A simulation experimental device for seepage prevention and deformation of cofferdams in deep water reservoirs under multiple working conditions

Abstract

This invention belongs to the field of hydraulic engineering model testing, specifically a multi-condition deep-water reservoir cofferdam seepage prevention deformation simulation experimental device. Addressing the problems of high cost, difficulty in observing internal deformation, and difficulty in reproducing water level change conditions in existing deep-water pressure simulations, the following solution is proposed: a simulation chamber, a displacement monitoring system, and a lifting mechanism. The lifting mechanism on the top of the simulation chamber controls the raising and lowering of the sealing cover. A flexible bladder is connected below the sealing cover and is connected to a water injection pipe and a pressure relief pipe with a quick-opening valve. Steel wires are pre-embedded in the model soil, passing through the sealed structure of the chamber wall and connecting to an external displacement gauge. This invention uses bladder pressurization instead of traditional water column loading to achieve high-pressure simulation with a small amount of water; it utilizes the steel wire conduction mechanism to convert internal deformation into measurable external displacement; and it combines a rapid pressure relief function to reproduce the sudden drop in water level, providing an effective experimental means for evaluating the performance of cofferdam seepage prevention systems under complex hydraulic conditions.

Description

Technical Field

[0001] This utility model relates to the field of water conservancy engineering technology, and in particular to a simulation experimental device for seepage prevention and deformation of cofferdams in deep water reservoirs under multiple working conditions. Background Technology

[0002] In the field of water conservancy engineering technology, multi-condition deep-water reservoir cofferdam seepage prevention deformation simulation experimental device is mainly used to study the mechanical response characteristics of cofferdam structure and seepage prevention system in deep water environment. This type of device provides experimental basis for evaluating the safety of cofferdam by simulating hydrostatic pressure and water level change process under different water depth conditions. Traditional experimental methods usually simulate hydrostatic pressure by directly injecting a large amount of water into the model box. Its working principle is based on Pascal's law, using the water body's own weight to form a pressure gradient. This method requires the construction of a sealed container that can withstand high pressure and the configuration of a corresponding water level control and measurement system.

[0003] However, existing technologies have several aspects that need improvement. Constructing experimental containers capable of simulating water depths of hundreds of meters is costly and poses safety hazards. The internal deformation of the soil and seepage prevention structure inside the model box under load is difficult to observe directly. Conventional surface measurement methods cannot obtain real deformation data. Furthermore, the experimental condition of constant water level is difficult to accurately simulate the dynamic water pressure impact on the cofferdam caused by rapid water level changes during actual reservoir operation. These factors limit the engineering guidance value of the experimental data. Therefore, we propose a multi-condition deep-water reservoir cofferdam seepage prevention deformation simulation experimental device to solve the above problems. Utility Model Content

[0004] The purpose of this invention is to address the shortcomings of existing technologies, such as high cost and safety risks in simulating water depths of 100 meters, difficulty in directly observing internal deformation, and inability to accurately simulate the impact of sudden water level drops, which limit the engineering application value of experimental data. Therefore, this invention proposes a multi-condition deep-water reservoir cofferdam seepage prevention deformation simulation experimental device.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A simulation experimental device for seepage prevention and deformation of cofferdams in deep water reservoirs under multiple working conditions includes a simulation box. The top opening of the simulation box is equipped with a sealing cover that can be raised and lowered by a lifting mechanism. The interior of the simulation box contains model soil.

[0007] The sealing cover is equipped with a pressure loading system, which includes a flexible bladder that is flexibly connected to the bottom of the sealing cover and a water injection pipe and a pressure relief pipe that penetrate the sealing cover. The water injection pipe and the pressure relief pipe are both connected to the flexible bladder, and the pressure relief pipe is equipped with a quick-opening valve.

[0008] A deformation monitoring system is provided on one side of the simulation box. The deformation monitoring system includes multiple mounting plates fixedly installed on the outside of the simulation box. At least two fixed tubes are fixedly embedded through the multiple mounting plates, and a displacement meter is fixedly installed in each fixed tube. The internal movable measuring end of the displacement meter is connected to the model soil through a transmission element.

[0009] In one possible design, the conductive element is a steel wire pre-embedded in the model soil, with one end of the steel wire fixedly connected to the model soil and the other end passing through a through hole in the side wall of the simulation box and fixedly connected to the internal movable measuring end of the corresponding displacement gauge.

[0010] In one possible design, a sealing sleeve is provided in the through hole of the side wall of the simulation box, and flexible sealant is filled between the sealing sleeve and the steel wire to form a dynamic sealing structure.

[0011] In one possible design, the lifting mechanism includes self-locking electric push rods symmetrically arranged on both sides of the simulation chamber. The output end of the electric push rod is fixedly connected to the bottom of the sealing cover plate. The bottom of the sealing cover plate is also provided with multiple guide rods, which slide through the top of the simulation chamber.

[0012] In one possible design, a tension spring is provided inside the fixed tube, with its two ends fixedly connected to the inner wall of the fixed tube and the internal movable measuring end of the displacement gauge, respectively, to apply a constant tension to the steel wire.

[0013] In one possible design, a sealing strip is provided between the sealing cover and the simulation box, and multiple mounting holes are provided at corresponding positions on the sealing cover and the simulation box. Fixing bolts are threaded into the mounting holes to further improve the sealing performance and safety of the sealing cover and the simulation box.

[0014] In one possible design, multiple reinforcing plates are fixedly provided on the outside of the simulation box, and the multiple mounting plates are fixedly disposed on the outside of two adjacent reinforcing plates.

[0015] In one possible design, the pressure loading system further includes a high-pressure water pump, a pressure sensor, and a controller. The high-pressure water pump is connected to a water injection pipe, the pressure sensor is used to monitor the pressure inside the flexible bag, and the controller is connected to both the high-pressure water pump and the pressure sensor to adjust the operating status of the high-pressure water pump based on the monitored pressure value.

[0016] In this application, firstly, before the experiment begins, the operator activates the electric push rods symmetrically arranged on both sides of the simulation box. The output end of the electric push rod pushes the sealing cover plate to rise vertically along the guide rod, opening the top opening of the simulation box. Inside the simulation box, the model soil is filled and the cofferdam model is constructed. At the same time, steel wires are pre-embedded at predetermined measuring points, so that one end of the steel wire is anchored in the soil and the other end is led out through the through hole in the side wall of the simulation box. The sealing sleeve set in the through hole and the steel wire are filled with flexible sealant, forming a dynamic sealing structure that can both ensure sealing and allow the steel wire to move freely.

[0017] After the model preparation is completed, the electric push rod drives the sealing cover to descend to the closed position. At this time, the sealing strip between the sealing cover and the simulation box is compressed. The operator inserts multiple fixing bolts into the corresponding mounting holes on the sealing cover and the simulation box and tightens them to ensure the sealing of the experimental chamber. The reinforcing plate on the outside of the simulation box provides support for the entire structure, and the mounting plate fixed on the adjacent reinforcing plate provides a stable base for the fixing tube on it.

[0018] During the pressure loading phase, an external high-pressure water pump injects pressurized water into the flexible bag through an injection pipe. The system, equipped with a pressure sensor and controller, monitors and adjusts the pressure inside the bag in real time, maintaining it precisely at the set value. As the pressure increases, the flexible bag gradually expands and fully adheres to the surface of the underlying model soil, applying a uniformly distributed normal pressure to simulate hydrostatic loads at different depths. During this process, the deformation within the model soil causes displacement of the pre-embedded steel wire. The displacement gauge is fixed to a fixed tube to provide a stable measurement reference. Its internal sliding measuring end is connected to the end of the steel wire. The movement of the steel wire is converted into linear displacement of the displacement gauge's sliding measuring end and accurately recorded. A tension spring inside the fixed tube connects to the inner wall of the tube and the sliding measuring end of the displacement gauge, respectively. This spring continuously applies a small balancing force to ensure the steel wire remains taut throughout the experiment, eliminating measurement errors that might result from wire slack and ensuring the real-time and accurate transfer of displacement.

[0019] When simulating a sudden drop in water level, the quick-opening valve on the pressure relief pipe is opened, and the high-pressure water in the flexible bag is quickly discharged through the pressure relief pipe. The system pressure drops sharply in a short time. This process can effectively reproduce the dynamic water pressure impact generated when the reservoir discharges floodwater rapidly. At this time, the deformation monitoring system can accurately record the response characteristics of the cofferdam and seepage prevention structure under sudden load changes. After the experiment, the fixing bolts are loosened, and the electric push rod drives the sealing cover to rise again. The guide rod ensures the smoothness and centering of the lifting process, preparing for subsequent experiments.

[0020] Beneficial effects: The multi-condition deep water reservoir cofferdam seepage prevention deformation simulation experimental device described in this utility model, through the loading system composed of flexible bags and pressure pipelines, can form a uniformly distributed high-pressure environment in the experimental area with a small amount of water, which significantly reduces the equipment manufacturing cost and operation risk, avoids the need to build large high-pressure containers, and reduces the water consumption in the experimental process, making it possible to conduct high water pressure simulation in a conventional laboratory.

[0021] In this utility model, the multi-condition deep water reservoir cofferdam seepage prevention deformation simulation experimental device, through the monitoring system composed of pre-embedded steel wire and external displacement gauge, can directly transmit the invisible deformation inside the model to the outside for accurate measurement. The non-stretchable characteristics of the steel wire ensure the accuracy of displacement transmission, while the external tension spring ensures that the steel wire is always in a taut state, thereby capturing the subtle deformation process inside the soil in real time.

[0022] In this invention, the multi-condition deep-water reservoir cofferdam seepage prevention deformation simulation experimental device can accurately simulate the water level change process at different rates through the coordinated work of the water injection pipe and the pressure relief pipe; the instantaneous opening of the quick-opening valve can realize the rapid release of pressure, reproduce the impact effect of the sudden drop in water level on the seepage prevention structure, and provide an effective experimental means for studying the stability of cofferdams under non-steady flow conditions.

[0023] In this invention, a flexible bladder and pressure pipeline system are used to create a uniform high pressure in the experimental area with a small amount of water, which significantly reduces equipment costs and safety risks. By using a monitoring structure with pre-embedded steel wires and external displacement gauges, internal deformation is directly transmitted to the outside, ensuring real-time and accurate capture of subtle changes in the soil. Combined with a water injection pipe and a pressure relief pipe with a quick-opening valve, accurate simulation of water level changes at different rates is achieved, especially the ability to reproduce the impact effect of a sudden drop in water level, providing an effective experimental means for studying the stability of cofferdams under unsteady flow conditions. Attached Figure Description

[0024] Figure 1 This is a three-dimensional structural schematic diagram of a multi-condition deep water reservoir cofferdam seepage prevention deformation simulation experimental device proposed in this utility model;

[0025] Figure 2 This is a three-dimensional structural diagram of the sealing cover plate of the multi-condition deep water reservoir cofferdam seepage prevention deformation simulation experimental device proposed in this utility model when the device is opened.

[0026] Figure 3 This is a partial cross-sectional three-dimensional structural schematic diagram of the simulation box of a multi-condition deep water reservoir cofferdam seepage prevention deformation simulation experimental device proposed in this utility model.

[0027] Figure 4This is a partial cross-sectional three-dimensional structural diagram of the fixed pipe of a multi-condition deep water reservoir cofferdam seepage prevention deformation simulation experimental device proposed in this utility model.

[0028] In the diagram: 1. Simulation box; 2. Sealing cover plate; 3. Model soil; 4. Flexible bag; 5. Water injection pipe; 6. Pressure relief pipe; 7. Electric push rod; 8. Guide rod; 9. Fixing pipe; 10. Displacement gauge; 11. Steel wire; 12. Tension spring; 13. Reinforcing plate; 14. Fixing bolt; 15. Mounting plate. Detailed Implementation

[0029] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.

[0030] In one embodiment: Refer to Figure 1-4 A simulation experimental device includes a simulation chamber 1, which serves as the basic load-bearing component for the experiment. Multiple reinforcing plates 13 are fixedly installed on its outer side. The reinforcing plates 13 are welded to the side walls of the simulation chamber 1, which improves the overall structural rigidity of the simulation chamber 1 and prevents deformation of the side walls caused by the high-pressure environment during the experiment, providing a stable foundation for subsequent loading and monitoring. A lifting mechanism is installed at the top opening of the simulation chamber 1. The lifting mechanism drives the sealing cover plate 2 to rise and fall, thereby completing the filling of the model soil 3 and sealing of the experimental chamber.

[0031] Specifically, the lifting mechanism includes self-locking electric push rods 7 symmetrically arranged on both sides of the simulation chamber 1. The bottom of the cylinder of the electric push rod 7 is fixedly connected to the outer wall of the simulation chamber 1, and its output end is fixed to the bottom of the sealing cover plate 2 by bolts. The self-locking electric push rod 7 has a self-locking function. When the sealing cover plate 2 is raised or lowered to the target position, the self-locking structure inside the electric push rod 7 can lock the extension length of the output end. This can support the weight of the sealing cover plate 2 itself and maintain the stability of the sealing cover plate 2 during the experimental loading process, preventing the sealing cover plate 2 from shifting due to the pressure inside the flexible bag 4, thus ensuring the sealing effect and experimental safety. Furthermore, the bottom of the sealing cover plate 2 is also provided with multiple guide rods 8. The top of the guide rod 8 is welded and fixed to the sealing cover plate 2, and the bottom end slides through the pre-set guide hole at the top of the simulation chamber 1. The guide rod 8 and the guide hole are fitted with a clearance. When the electric push rod 7 drives the sealing cover plate 2 to rise or fall, the guide rod 8 can limit the movement direction of the sealing cover plate 2, prevent it from shifting horizontally, and ensure that the sealing cover plate 2 is accurately aligned with the top opening of the simulation chamber 1.

[0032] A sealing strip is provided between the sealing cover 2 and the top opening edge of the simulation chamber 1. The sealing strip is made of elastic rubber and is fixed to the bottom edge of the sealing cover 2 by adhesive bonding. Specifically, multiple mounting holes are provided at corresponding positions on the sealing cover 2 and the simulation chamber 1. When the sealing cover 2 is lowered to the closed position, the operator inserts the fixing bolt 14 into the mounting hole and tightens it. The preload of the fixing bolt 14 compresses the sealing strip, forming an initial seal. Combined with the locking action of the self-locking electric push rod 7, the sealing performance of the experimental chamber can be further improved, providing reliable protection for high-pressure loading conditions.

[0033] The sealing cover plate 2 is equipped with a pressure loading system, which includes a flexible bag 4, a water injection pipe 5, and a pressure relief pipe 6. The flexible bag 4 is made of high-strength, aging-resistant rubber material, and its top is flexibly connected to the bottom of the sealing cover plate 2. Specifically, the flexible connection is achieved through a ring-shaped metal pressure ring and bolts. The ring-shaped metal pressure ring presses the top edge of the flexible bag 4 into the mounting groove at the bottom of the sealing cover plate 2. A small gap is reserved between the pressure ring and the sealing cover plate 2, and the connection part of the flexible bag 4 retains a certain amount of expansion and contraction allowance. This connection method allows the flexible bag 4 to undergo a certain deformation displacement when it is filled with water and expands, ensuring that it can fully fit with the surface of the underlying model soil 3 and avoid uneven pressure transmission caused by rigid connection. The water injection pipe 5 and the pressure relief pipe 6 are both installed through the sealing cover plate 2. The bottom ends of both are connected to the inside of the flexible bag 4, and the top ends extend above the sealing cover plate 2. A quick-opening valve is installed on the pressure relief pipe 6. The quick-opening valve is pneumatically controlled and can be fully opened in a short time.

[0034] Furthermore, the pressure loading system also includes a high-pressure water pump, a pressure sensor, and a controller. The outlet of the high-pressure water pump is connected to the water injection pipe 5 via a pipe. The probe of the pressure sensor extends into the flexible bag 4, and its signal output is electrically connected to the controller. The controller's control output is electrically connected to the high-pressure water pump. Based on this, the pressure sensor can monitor the pressure value inside the flexible bag 4 in real time and transmit it to the controller. The controller adjusts the operating state of the high-pressure water pump according to preset pressure parameters to achieve precise pressure control. Continuous water injection through the water injection pipe 5 can simulate a rising water level, while opening the quick-opening valve to rapidly drain water from the pressure relief pipe 6 can simulate a sudden drop in water level, meeting the needs of multi-condition experiments. A uniform high-pressure environment can be formed using the flexible bag 4 with a small amount of water, eliminating the need to construct large high-pressure containers, reducing equipment costs and operational risks, while also reducing water consumption, making it suitable for conventional laboratory conditions.

[0035] A deformation monitoring system is installed on one side of the simulation box 1. This system includes multiple mounting plates 15, each fixed to the outside of two adjacent reinforcing plates 13 and connected to the reinforcing plates 13 by bolts. The reinforcing plates 13 provide a stable support foundation for the mounting plates 15, preventing measurement errors caused by shaking of the installation reference during monitoring. At least two fixing tubes 9 are fixedly embedded through the multiple mounting plates 15. The fixing tubes 9 are made of seamless steel pipe and are fixed to the mounting plates 15 by welding. A displacement gauge 10 is fixedly installed inside each fixing tube 9. The body of the displacement gauge 10 is fixed to the inner wall of the fixing tube 9 by bolts, and its internal movable measuring end is connected to the model soil 3 through a transmission element.

[0036] Furthermore, a tension spring 12, made of stainless steel, is installed inside the fixing tube 9. One end of the tension spring 12 is fixed to the inner wall of the fixing tube 9 via a hook, and the other end is fixedly connected to the internal movable measuring end of the displacement gauge 10 via a hook. The tension spring 12 is in a stretched state under natural conditions, applying a constant tension to the steel wire 11. This ensures that the steel wire 11 remains taut throughout the experiment, eliminating potential displacement transmission lag or errors caused by slack in the steel wire 11. This guarantees the real-time performance and accuracy of deformation measurement, enabling the capture of minute deformations within the soil.

[0037] This application can be used in the field of water conservancy engineering technology, or in other fields applicable to this application.

[0038] In another embodiment: Reference Figure 2-4 Based on Embodiment 1, an improved version of this embodiment is proposed: a multi-condition deep-water reservoir cofferdam seepage prevention deformation simulation experimental device, applied in the field of water conservancy engineering technology. The structure of this embodiment is basically the same as the aforementioned embodiment, except that: specifically, the transmission element is a steel wire 11, made of high-strength stainless steel. One end of the steel wire 11 is pre-embedded and fixed to the soil during the filling process of the model soil 3, while the other end passes through a through-hole in the side wall of the simulation box 1 and is fixedly connected to the internal movable measuring end of the displacement gauge 10. The steel wire 11 has non-stretchable characteristics, enabling it to directly transmit the deformation inside the model soil 3 to the displacement gauge 10, achieving external measurement of internal deformation. Preferably, a sealing sleeve is provided inside the through-hole in the side wall of the simulation box 1. The sealing sleeve is made of copper and is fixedly connected to the through-hole by threads. Flexible sealant is filled between the inner wall of the sealing sleeve and the steel wire 11, forming a dynamic sealing structure. In this dynamic sealing structure, the flexible sealant can fill the gap between the steel wire 11 and the sealing sleeve, ensuring the sealing of the simulation box 1. At the same time, the flexible sealant has a certain elasticity, allowing the steel wire 11 to move axially with the deformation of the model soil 3, thus avoiding the sealing structure from hindering the transmission of displacement.

[0039] The accompanying drawings in this application are for illustrative purposes only. The dimensions and shapes of the components shown are not actual limitations but are merely schematic representations. In actual implementation, the components can be reasonably configured and adjusted according to specific needs and actual conditions.

[0040] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A multi-condition deep reservoir cofferdam anti-seepage deformation simulation experiment device, comprising a simulation box (1), characterized in that, The top opening of the simulation box (1) is equipped with a sealing cover plate (2) that can be raised and lowered by a lifting mechanism, and the interior of the simulation box (1) is equipped with model soil (3). The sealing cover (2) is provided with a pressure loading system. The pressure loading system includes a flexible bag (4) that is flexibly connected to the bottom of the sealing cover (2) and a water injection pipe (5) and a pressure relief pipe (6) that penetrate the sealing cover (2). The water injection pipe (5) and the pressure relief pipe (6) are both connected to the flexible bag (4). The pressure relief pipe (6) is provided with a quick-opening valve. A deformation monitoring system is provided on one side of the simulation box (1). The deformation monitoring system includes multiple mounting plates (15) fixedly installed on the outside of the simulation box (1). At least two fixed tubes (9) are fixedly embedded through the multiple mounting plates (15), and a displacement meter (10) is fixedly installed in each fixed tube (9). The internal movable measuring end of the displacement meter (10) is connected to the model soil (3) through a transmission element.

2. The multi-working-condition seepage deformation simulation experimental device for a deep reservoir cofferdam according to claim 1, characterized in that, The conductive element is a steel wire (11) pre-embedded in the model soil (3). One end of the steel wire (11) is fixedly connected to the model soil (3), and the other end passes through the through hole in the side wall of the simulation box (1) and is fixedly connected to the internal movable measuring end of the corresponding displacement gauge (10).

3. The multi-working-condition deep reservoir cofferdam seepage deformation simulation experiment device according to claim 2, characterized in that, A sealing sleeve is provided in the through hole of the side wall of the simulation box (1), and flexible sealant is filled between the sealing sleeve and the steel wire (11) to form a dynamic sealing structure.

4. The multi-working-condition deep reservoir cofferdam seepage deformation simulation experiment device according to claim 1, characterized in that, The lifting mechanism includes self-locking electric push rods (7) symmetrically arranged on both sides of the simulation box (1). The output end of the electric push rod (7) is fixedly connected to the bottom of the sealing cover plate (2). The bottom of the sealing cover plate (2) is also provided with multiple guide rods (8). The guide rods (8) slide through the top of the simulation box (1).

5. The multi-condition deep reservoir cofferdam seepage deformation simulation experiment device according to claim 1, characterized in that, The fixed tube (9) is provided with a tension spring (12), and the two ends of the tension spring (12) are fixedly connected to the inner wall of the fixed tube (9) and the internal movable measuring end of the displacement gauge (10) respectively, for applying a constant tension to the steel wire (11).

6. The multi-condition deep-water reservoir cofferdam seepage prevention deformation simulation experimental device according to claim 1, characterized in that, A sealing strip is provided between the sealing cover (2) and the simulation box (1). Multiple mounting holes are provided at corresponding positions of the sealing cover (2) and the simulation box (1). Fixing bolts (14) are threaded into the mounting holes to further improve the sealing performance and safety of the sealing cover (2) and the simulation box (1).

7. The multi-condition deep-water reservoir cofferdam seepage prevention deformation simulation experimental device according to claim 1, characterized in that, Multiple reinforcing plates (13) are fixedly provided on the outside of the simulation box (1), and multiple mounting plates (15) are fixedly provided on the outside of two adjacent reinforcing plates (13).

8. The multi-condition deep-water reservoir cofferdam seepage prevention deformation simulation experimental device according to claim 1, characterized in that, The pressure loading system also includes a high-pressure water pump, a pressure sensor and a controller. The high-pressure water pump is connected to the water injection pipe (5). The pressure sensor is used to monitor the pressure inside the flexible bag (4). The controller is connected to the high-pressure water pump and the pressure sensor respectively, and is used to adjust the operating status of the high-pressure water pump according to the monitored pressure value.

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