A physical model device for simulating confining pressure and internal water pressure of a diversion tunnel and a method of use

Abstract

The present application belongs to the field of simulation detection technology, and particularly relates to a physical model device for simulating confining pressure and internal water pressure of a diversion tunnel and a use method thereof. The model device comprises a confining pressure loading device, an internal water pressure loading device, a base and a tunnel lining model. The confining pressure loading device is applied in the form of air pressure to the outer surface of the tunnel lining model, the internal water pressure loading device is applied in the form of water pressure to the inner surface of the tunnel lining model, and the base is used for fixing the tunnel lining model. In assembly and use, the accuracy of pressure application in the physical model test of the diversion tunnel is improved by simulating actual normal working conditions, and the device can better simulate the confining pressure and internal water pressure conditions of the actual diversion tunnel in operation and restore the internal and external operating environment of the tunnel. The present application has simple structure and easy operation, can simulate the effect and influence of the confining pressure and internal water pressure on the diversion tunnel structure to the greatest extent, and provides a reliable test basis for the design and construction of the hydraulic tunnel.

Description

Technical Field

[0001] This invention relates to the field of simulation testing technology, specifically to a physical model device and method for simulating the confining pressure and internal water pressure of a water diversion tunnel. Background Technology

[0002] Water diversion tunnels are key structures in water conservancy projects. When hydraulic tunnels operate as "pressurized tunnels," they will frequently and inevitably encounter situations where internal water pressure and surrounding rock pressure (referred to as confining pressure) work together. The design and construction quality directly affects the safety and operational efficiency of the project.

[0003] Existing physical model testing devices have significant shortcomings in simulating the combined loading of tunnel confining pressure and internal water pressure, making it difficult to realistically and accurately simulate the pressure conditions experienced by actual tunnels, thus resulting in insufficient representativeness of the test results. Furthermore, the pressurization devices in traditional indoor tunnel models are poorly designed and complex to operate, reducing test efficiency and data accuracy while increasing costs and time.

[0004] In summary, there is an urgent need to develop a physical model device for simulating the mechanical response of the surrounding rock-lining structure under the combined effects of confining pressure and internal water pressure in water diversion tunnels. This device should possess higher simulation accuracy while being easier to operate. The system must be able to accurately simulate the internal water pressure environment during actual tunnel operation, providing reliable and realistic loading conditions for experiments. This will provide reliable support for the design and optimization of physical model tests for water diversion tunnels, thus promoting the development of water conservancy projects. Summary of the Invention

[0005] The purpose of this invention is to provide a physical model device for simulating the confining pressure and internal water pressure of a water diversion tunnel, thereby addressing the aforementioned problems in the prior art. This ensures the accuracy of the physical model test device for the water diversion tunnel, better simulates the confining pressure and internal water pressure experienced by the water diversion tunnel in actual operation, and provides conditions for obtaining more accurate mechanical response laws and deformation failure of the surrounding rock-lining structure of the water diversion tunnel through testing.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solution: The technical solution includes two aspects. The first aspect is a physical model device for simulating the confining pressure and internal water pressure of a water diversion tunnel, including: a confining pressure loading device, an internal water pressure loading device, a base, and a tunnel lining model.

[0007] The confining pressure loading device applies air pressure to the outer surface of the tunnel lining model, the internal water pressure loading device applies water pressure to the inner surface of the tunnel lining model, and the base is used to fix the tunnel lining model.

[0008] Furthermore, the confining pressure loading device includes a transparent rubber airbag, a hollow threaded tie rod, a stainless steel hollow frame, an air guide pipe, an air inlet valve, and an electric air pump.

[0009] The transparent rubber airbag is used to cover the outer wall of the tunnel lining model. It is a ring-shaped cylinder made of transparent rubber, with an inner wall and an outer wall. There is a gas chamber between the inner wall and the outer wall. Multiple flexible sealed inflation joints are arranged in an array on the outer wall. The flexible sealed inflation joints are connected to the gas chamber.

[0010] The stainless steel hollow frame has a hollow structure with multiple air outlets on its inner wall and air inlets on its outer wall.

[0011] The hollow threaded tie rod is used to provide a gas channel for the flexible sealed air inflatable joint and to provide radial support for the tunnel lining model. Its axial length is adjustable. One end is connected to the flexible sealed air inflatable joint of the transparent rubber airbag, and the other end is connected to the air outlet of the stainless steel hollow frame.

[0012] The air intake valve is equipped with an air outlet connection column and an air intake connection column.

[0013] The electric air pump is used to provide air to the transparent rubber airbag. The electric air pump is connected to the air intake connection post of the air intake valve through the air guide tube. The air outlet connection post of the air intake valve is connected to the stainless steel hollow frame air inlet through the air guide tube.

[0014] The internal water pressure loading device includes a perforated gasket, an inlet valve, a water supply pipe, a water pump, a rubber sleeve, and a clamp.

[0015] The perforated gasket has a cross-sectional shape and size that matches the cross-sectional shape and size of the tunnel lining model. Its lower end is placed on the upper end surface of the tunnel lining model, and its upper end is welded to the water inlet valve. A rubber sleeve is fitted at the connection point with the tunnel lining model, and two hoop rings are fitted on the outer surface of the rubber sleeve.

[0016] The base includes a first groove for fixing a stainless steel hollow frame and a second groove for fixing a tunnel lining model, wherein a plug for sealing the lower opening of the tunnel lining model is glued and fixed in the second groove.

[0017] Furthermore, the hollow threaded tie rod includes a plurality of sub-threaded tie rods connected in sequence.

[0018] During assembly, all connections between the air guide tubes and the stainless steel hollow frame air inlet, the air guide tubes and the air inlet connecting column of the air inlet valve, the hollow threaded tie rods and the flexible sealing inflation joint of the transparent rubber airbag, the stainless steel hollow frame air outlet and the hollow threaded tie rods, and the connections between the threaded tie rods of each section are firmly bonded with high-strength adhesive, and a sealing strip is wrapped around the outer perimeter of the interface for secondary sealing treatment.

[0019] High-strength adhesive and wrapping sealing strips ensure the airtightness and mechanical strength of the device.

[0020] Furthermore, the stainless steel hollow frame is a hollow square ring. The stainless steel hollow frame is used to provide gas channels and support points for the hollow threaded tie rod. There are 4 air outlets in each layer, which are respectively set at the four inner top corners of the square ring. There are a total of 6 layers along the height direction of the stainless steel hollow frame. Each of the four outer walls of the stainless steel hollow frame is equipped with an air inlet.

[0021] Each layer of the outer wall of the transparent rubber airbag has four flexible sealing inflation joints evenly distributed radially, and the outer wall of the transparent rubber airbag has a total of six layers evenly distributed axially.

[0022] The air vents are located at the four inner corners of the square ring, providing maximum support stress for the tunnel lining model.

[0023] Furthermore, the stainless steel hollow frame adopts a hollow square ring with a hollow structure and hollow holes on the side wall.

[0024] The hollow stainless steel frame with its openwork structure facilitates strong adhesive bonding and secondary sealing.

[0025] The second aspect involves using the physical model device for simulating the confining pressure and internal water pressure of a water diversion tunnel as described in the first aspect, and then assembling and using the physical model device for simulating the confining pressure and internal water pressure of a water diversion tunnel.

[0026] The method includes the following steps: Step 1: Equipment preparation: Based on the determined axial length of the tunnel lining model and the thickness of the perforated gasket, prepare a stainless steel hollow frame and a circular cylindrical transparent rubber airbag according to the predetermined axial dimensions, so that the transparent rubber airbag is evenly wrapped around the outer wall of the tunnel lining model.

[0027] Step 2: Assembly of the confining pressure loading device Step 2-1: Pre-pressurize and check the airtightness of the transparent rubber airbag. If the airtightness meets the requirements, proceed to the next step. Step 2-2: Assembly between the transparent rubber airbag, tunnel lining model, and base. First, the outer wall of the tunnel lining model is covered with a transparent rubber airbag; then, the tunnel lining model covered with the transparent rubber airbag is inserted into the groove of the plug in the second groove of the base; finally, the stainless steel hollow frame is inserted into the first groove. Steps 2-3: Connection between the transparent rubber airbag and the stainless steel hollow frame First, adjust the length of the hollow threaded rods according to the gap between the transparent rubber airbag and the stainless steel hollow frame; then connect all the hollow threaded rods to the flexible sealing inflation joint of the transparent rubber airbag and the air outlet of the stainless steel hollow frame, and ensure that the length of each hollow threaded rod is consistent within the device. Steps 2-4: Airtight treatment of hollow threaded tie rods High-strength adhesive is used to firmly bond the hollow threaded tie rods to the transparent rubber airbags, the stainless steel hollow frame to the hollow threaded tie rods, and the connections between the threaded tie rods of each segment. A sealing strip is then wrapped around the outer perimeter of the interface for secondary sealing. Steps 2-5: Piping and Equipment Installation Use an air guide tube to connect the air intake connection post of the air intake valve and the air outlet connection post of the electric air pump. Use an air guide tube to connect the air outlet connection column of the air inlet valve to the air inlet nozzle of the stainless steel hollow frame; Steps 2-6: Airtightening of Pipelines Use strong adhesive to seal the pipe connections, and then seal the joints with a sealing strip.

[0028] Step 3: Assembly of the internal water pressure loading device: Step 3-1: The upper end of the perforated gasket is welded to the water inlet valve to form a single unit; Step 3-2: Place the lower end of the perforated gasket in the internal water pressure loading device on the tunnel lining model, and then wrap the connection with a transparent rubber airbag; Step 3-3: A rubber sleeve is fitted at the connection between the perforated gasket and the tunnel lining model. Two rings are fitted on the outer surface of the rubber sleeve. One ring is fitted on the water inlet valve and the other ring is fitted on the tunnel lining model, so that the perforated gasket and the tunnel lining model are in tight contact and connection. Steps 3-4: Connect the water supply pipe between the water pump and the inlet valve; Steps 3-5: Use strong adhesive to bond the water inlet valve, water pipe and water pump connection, and then use sealing strips to seal the bonded joints a second time.

[0029] Step 4, Applying confining pressure and internal water pressure: Based on the confining pressure and internal water pressure values ​​required for the tunnel physical model test, proceed with steps 4-1 and 4-2 simultaneously; Step 4-1: Start the electric air pump to deliver gas through the air pipe, through the air inlet valve, through the stainless steel hollow frame, and then through the hollow threaded tie rod to the transparent rubber airbag until the pressure display shows that the air pressure inside the transparent rubber airbag has reached the set confining pressure value. Then turn off the electric air pump. The transparent rubber airbag will inflate and expand, and its inner wall will compress against the outer wall of the tunnel lining model, thereby simulating the effect of confining pressure applied to the outer wall of the tunnel. Step 4-2: Start the water pump to deliver water through the water pipe, inlet valve, and perforated gasket into the tunnel lining model until the water pump pressure display shows that the internal water pressure in the tunnel lining model has reached the set water pressure value. Then turn off the water pump. At this time, the set water pressure is applied to the inner surface of the tunnel lining model, thereby simulating the effect of internal water pressure applied to the inner wall of the tunnel. Step 4-3: After holding the pressure for 5-10 minutes, conduct a test experiment on the physical model device of the tunnel lining model.

[0030] Based on the above, the present invention includes at least one of the following beneficial technical effects: 1. The method of simulating tunnel confining pressure loading by using air pressure and transmitting pressure through rubber airbags eliminates the need for direct contact between the medium and the tunnel model device, does not alter the material properties of the tunnel model device, and does not affect the strength of the tunnel model device; water pressure is applied to the upper part of the tunnel lining model by a water pump; both methods can realistically simulate the impact of confining pressure and internal water pressure on the tunnel lining model during the operation of the water diversion tunnel.

[0031] 2. Inflate the stainless steel hollow frame with an electric air pump, and transmit the air pressure through the air pipe and hollow threaded tie rod, causing the rubber airbag to deform radially; use a water pump to deliver water through the water pipe and then through the gasket, so as to continuously, stably, evenly and safely transmit the pressure to the outer and inner surfaces of the tunnel lining model device.

[0032] 3. For tunnel lining model structures with rectangular, horseshoe-shaped, or other cross-sections, simply changing the distribution of rubber airbags of different shapes, perforated gaskets of different cross-sections, and hollow threaded tie rods can ensure that the pressure is evenly and fully transmitted to the tunnel model device. For tunnel lining model structures with different cross-sectional sizes, adjusting the length of the hollow threaded tie rods can meet the test requirements. Compared with existing pressurization devices, this device has a simpler structure, is easier to operate, and has greater test adaptability.

[0033] 4. In the tunnel physical model test, wiring holes can be pre-drilled on the water supply pipe to provide routing paths for cables of various sensors. The external deformation and failure characteristics of the tunnel lining model can be observed and recorded through the transparent rubber airbag. Sensors inside the tunnel can observe the internal deformation and failure of the tunnel structure model lining, as well as the stress on the lining, providing a more intuitive understanding of the mechanical response and deformation and failure characteristics of the surrounding rock-lining structure of the water diversion tunnel. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the overall structure of a physical model device for simulating the confining pressure and internal water pressure of a water diversion tunnel according to a first embodiment of the present invention; Figure 2 This is a schematic diagram of the confining pressure loading device in Embodiment 1; Figure 3 This is a schematic diagram of the internal water pressure loading device in Embodiment 1; Figure 4 This is a schematic diagram of a perforated gasket in an internal water pressure loading device. Figure 5 A structural schematic diagram of the inlet valve, perforated gasket, and tunnel lining model; Figure 6 This is a schematic diagram of the installation structure of the rubber sleeve and clamp ring in Example 1; Figure 7 This is a schematic diagram of the base structure in Embodiment 1; Figure 8 This is a structural schematic diagram of the tunnel lining model in Example 1; Figure 9 This is a schematic diagram of the structure of the transparent rubber airbag in Example 1.

[0035] In the picture: Confining pressure loading device 1; transparent rubber airbag 11; hollow threaded tie rod 12; stainless steel hollow frame 13; air duct 14; air inlet valve 15; electric air pump 16; pressure display 17; internal water pressure loading device 2; perforated gasket 21; water inlet valve 22; water supply pipe 23; water pump 24; rubber sleeve 25; hoop 26; base 3; first groove 31; second groove 32; plug 33; tunnel lining model 4. Detailed Implementation

[0036] To enable those skilled in the art to better understand the present invention, further detailed description of embodiments is provided below with reference to the accompanying drawings and examples. The embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention. Example 1

[0037] like Figure 1-9 As shown, the present invention discloses a physical model device for simulating the confining pressure and internal water pressure of a water diversion tunnel, including a confining pressure loading device 1, an internal water pressure loading device 2, a base 3, and a tunnel lining model 4.

[0038] The confining pressure loading device 1 includes a transparent rubber airbag 11, a hollow threaded tie rod 12, a stainless steel hollow frame 13, an air guide pipe 14, an air inlet valve 15, and an electric air pump 16.

[0039] The transparent rubber airbag 11 is used to cover the outer wall of the tunnel lining model 4. It is a ring-shaped cylinder made of transparent rubber, with an inner wall and an outer wall. There is a gas chamber between the inner wall and the outer wall. The transparent material is easy for manual observation and sensor detection. Multiple flexible sealed inflation joints are arranged in an array on the outer wall. The flexible sealed inflation joints are connected to the gas chamber and are used for inflation. After the gas chamber is inflated, the inner wall and the outer wall expand inward and outward.

[0040] Please see Figure 9 In this embodiment, four flexible sealing inflation joints are evenly distributed radially on the outer wall of the transparent rubber airbag 11, forming one layer, and six layers are evenly distributed axially on the outer wall of the transparent rubber airbag 11.

[0041] The hollow threaded tie rod 12 is used to provide a gas channel for the flexible sealing gas inflator and to provide radial support for the tunnel lining model 4. The axial length of the hollow threaded tie rod 12 is adjustable, so that the device can adapt to the physical model of the tunnel lining model with different cross-sections.

[0042] In this embodiment, based on the cross-sectional shape and axial length of the tunnel lining model 4, six sets of hollow threaded tie rods are provided. Each set of tie rods includes four hollow threaded tie rods 12. Each hollow threaded tie rod includes multiple sub-threaded tie rods connected sequentially by threads. Adjacent rod segments are marked as sub-threaded segment one and sub-threaded segment two, respectively. One end of the sub-threaded tie rod segment two is provided with a radially elastic locking sleeve, which is formed by dividing the rod end through an axial cut. The end of the sub-threaded segment one can be inserted into the locking sleeve of the sub-threaded segment two and tightened by a locking nut, causing the locking sleeve to contract radially, thereby fastening the two rod segments together. Pulling and tightening sub-threaded segment one and sub-threaded segment two allows the axial length of the hollow threaded tie rod 12 to be adjustable.

[0043] In this embodiment, the stainless steel hollow frame 13 is a hollow square ring. The stainless steel hollow frame 13 is used to provide a gas channel and support force point for the hollow threaded tie rod 12. Multiple air outlets are provided on the inner side wall of the stainless steel hollow frame 13, and the multiple air outlets correspond to the flexible sealing air inflator. Each of the four outer side walls of the stainless steel hollow frame 13 is provided with an air inlet. The stainless steel hollow frame 13 has a cavity to contain gas. The air outlets are located at the four inner apex positions of the square ring. The inner apex positions can provide maximum stress support for the tunnel lining model 4.

[0044] One end of the hollow threaded tie rod 12 is connected to the flexible sealed inflation joint of the transparent rubber airbag 11, and the other end is connected to the air outlet of the stainless steel hollow frame 13. The connection between them is sealed with strong adhesive, and a sealing strip is used to perform secondary sealing at the bonding point.

[0045] As another possible solution, the stainless steel hollow frame 13 adopts a hollow structure with hollow holes on the side walls, which facilitates strong adhesive sealing and secondary sealing.

[0046] The air inlet valve 15 of the confining pressure loading device 1 is connected to the stainless steel hollow frame 13 and the electric air pump 16 through an air guide pipe 14. The air inlet valve 15 has four air outlet connection posts. Each air outlet connection post is connected to the air inlet on one of the outer side walls of the stainless steel hollow frame 13 by an air guide pipe 14. The air inlet valve 15 has one air inlet connection post. The air inlet connection post is connected to the air outlet connection post of the electric air pump 16 by an air guide pipe 14. The connection is sealed with strong adhesive and sealed with a sealing strip.

[0047] The electric air pump 16 should be stable and durable, capable of efficient and rapid air supply, and have an adjustable working pressure that meets the test requirements.

[0048] When in use, start the electric air pump 16 to deliver gas through the air pipe 14, through the air inlet valve 15, through the stainless steel hollow frame 13, and then through the hollow threaded rod 12 to the transparent rubber airbag 11 until the pressure display 17 shows that the air pressure inside the transparent rubber airbag 11 has been loaded to the set confining pressure value, and then turn off the electric air pump 16.

[0049] The internal water pressure loading device 2 includes a perforated gasket 21, an inlet valve 22, a water supply pipe 23, a water pump 24, a rubber sleeve 25, and a clamp 26.

[0050] The cross-sectional shape and size of the perforated gasket 21 are determined according to the cross-sectional shape and size of the tunnel lining model 4. Its lower end is placed on the upper end surface of the tunnel lining model 4. The upper end of the perforated gasket 21 is connected to the water inlet valve 22 by welding. The function of the perforated gasket 21 is to allow water to enter the tunnel lining model 4 through its holes and to make the upper surface of the tunnel lining model 4 uniformly stressed.

[0051] A rubber sleeve 25 is fitted at the connection between the perforated gasket 21 and the tunnel lining model 4. Two rings 26 are fitted on the outer surface of the rubber sleeve 25. One ring 26 is fitted on the water inlet valve 22, and the other ring 26 is fitted on the tunnel lining model 4, so that the perforated gasket 21 and the tunnel lining model 4 are in close contact and connection.

[0052] The water pump 24 is characterized by adjustable water volume and flow rate and the ability to operate continuously. The water pump 24 and the inlet valve 22 of the internal water pressure loading device 2 are connected by a water supply pipe 23. The connection is bonded with strong adhesive and then sealed with a sealing strip. The water pump 24 is equipped with a water pressure display screen and operation buttons.

[0053] When in use, start the water pump 24. The water flows through the water pipe 23, the inlet valve 22, and then through the perforated gasket 21 into the tunnel lining model 4 until the water pressure display on the water pump 24 shows that the internal water pressure in the tunnel lining model 4 has reached the set water pressure value. Then, turn off the water pump 24.

[0054] The base 3 includes a first groove 31 for fixing the stainless steel hollow frame 13 and a second groove 32 for fixing the tunnel lining model 4. A plug 33 for sealing the lower opening of the tunnel lining model 4 is glued and fixed in the second groove 32. The plug 33 has a ring-groove-platform structure and is made of rubber. The cross-sectional shape and size of the plug 33 are adapted to the cross-sectional shape and size of the tunnel lining model 4.

[0055] The tunnel lining model 4 is a tubular column. The cross-section of the tunnel lining model 4 is circular, horseshoe-shaped, or a combination of arc and square. In this embodiment, the cross-section of the tunnel lining model 4 is circular.

[0056] During assembly, firstly, the transparent rubber airbags 11 are wrapped around the outer wall of the tunnel lining model 4. The uppermost row of flexible sealing inflation joints of the transparent rubber airbags 11 is flush with the upper edge of the tunnel lining model 4, and the lowermost row of flexible sealing inflation joints of the transparent rubber airbags 11 is flush with the lower edge of the tunnel lining model 4. Next, the lower end of the tunnel lining model 4 covered with the transparent rubber airbags 11 is inserted into the groove of the plug 33 in the second groove 32 of the base 3, so that the tunnel lining model 4 and the plug 33 are in close contact, and the transparent rubber airbags 11 are in close contact with the inner wall of the second groove 32. Then, the stainless steel hollow frame 13 is inserted into the first groove 31, and the stainless steel hollow frame 13 is in close contact with the first groove 31. Example 2

[0057] This embodiment uses the physical model device for simulating the confining pressure and internal water pressure of a water diversion tunnel as described in Embodiment 1, and describes the assembly and usage method of the physical model device for simulating the confining pressure and internal water pressure of a water diversion tunnel.

[0058] Please see Figure 1-9 The method includes the following steps: Step 1: Equipment preparation: Based on the determined axial length of the tunnel lining model 4 and the thickness of the perforated gasket 21, prepare a stainless steel hollow frame 13 and a circular cylindrical transparent rubber airbag 11 according to the predetermined axial dimensions, so that the transparent rubber airbag 11 is evenly wrapped around the outer wall of the tunnel lining model 4.

[0059] Step 2: Assembly of confining pressure loading device 1 Step 2-1: Pre-pressurize and check the airtightness of the transparent rubber airbag 11. If the airtightness meets the requirements, proceed to the next step. Step 2-2: Assembly between transparent rubber airbag 11, tunnel lining model 4 and base 3 First, the transparent rubber airbag 11 is wrapped around the outer wall of the tunnel lining model 4; then the tunnel lining model 4 wrapped with the transparent rubber airbag 11 is inserted into the groove of the plug 33 in the second groove 32 of the base 3; finally, the stainless steel hollow frame 13 is inserted into the first groove 31. Steps 2-3: Connection between the transparent rubber airbag 11 and the stainless steel hollow frame 13 First, adjust the length of the hollow threaded rod 12 according to the gap between the transparent rubber airbag 11 and the stainless steel hollow frame 13; then connect all the hollow threaded rods 12 to the flexible sealing inflation joint of the transparent rubber airbag 11 and the air outlet of the stainless steel hollow frame 13 respectively, and ensure that the length of each hollow threaded rod is consistent in the device. Steps 2-4: Airtight treatment of hollow threaded tie rod 12 At the joints between the hollow threaded tie rod 12 and the transparent rubber airbag 11, the joints between the stainless steel hollow frame 13 and the hollow threaded tie rod 12, and the connections between the threaded tie rods of each segment, a high-strength adhesive is used for firm bonding, and a sealing strip is wrapped around the outer periphery of the interface for secondary sealing treatment. Steps 2-5: Piping and Equipment Installation Use an air guide tube 14 to connect the air intake connection post of the air intake valve 15 and the air outlet connection post of the electric air pump 16. An air guide tube 14 is used to connect the air outlet connection column of the air inlet valve 15 to the air inlet of the stainless steel hollow frame 13. Steps 2-6: Airtightening of Pipelines Use strong adhesive to seal the pipe connections, and then seal the joints with a sealing strip.

[0060] Step 3: Assembly of internal water pressure loading device 2 Step 3-1: The upper end of the perforated gasket 21 is welded to the water inlet valve 22 to form a single unit; Step 3-2: Place the lower end of the perforated gasket 21 in the internal water pressure loading device on the tunnel lining model 4, and then wrap the connection with the transparent rubber airbag 11. Step 3-3: A rubber sleeve 25 is fitted over the connection between the perforated gasket 21 and the tunnel lining model 4. Two rings 26 are fitted on the outer surface of the rubber sleeve 25. One ring 26 is fitted on the water inlet valve 22, and the other ring 26 is fitted on the tunnel lining model 4, so that the perforated gasket 21 and the tunnel lining model 4 are in close contact and connection. Steps 3-4: Connect the water supply pipe 23 between the water pump 24 and the inlet valve 22; Steps 3-5: Use strong adhesive to bond the connection between the water inlet valve 22, the water supply pipe 23 and the water pump 24, and then use a sealing strip to seal the bonded joints a second time.

[0061] Step 4, Applying confining pressure and internal water pressure: Based on the confining pressure and internal water pressure values ​​required for the tunnel physical model test, proceed with steps 4-1 and 4-2 simultaneously; Step 4-1: Start the electric air pump 16 to deliver gas through the air pipe 14, through the air inlet valve 15, through the stainless steel hollow frame 13, and then through the hollow threaded tie rod 12 to the transparent rubber airbag 11 until the pressure display 17 shows that the air pressure inside the transparent rubber airbag 11 has reached the set confining pressure value. Then turn off the electric air pump 16. The transparent rubber airbag 11 inflates and expands. Its inner wall compresses the outer wall of the tunnel lining model, thereby simulating the effect of confining pressure applied to the outer wall of the tunnel. Step 4-2: Start the water pump 24 to deliver water through the water pipe 23, through the inlet valve 22, and then through the perforated gasket 21 into the tunnel lining model 4 until the water pressure display screen of the water pump 24 shows that the internal water pressure in the tunnel lining model 4 has been loaded to the set water pressure value. Then turn off the water pump 24. At this time, the set water pressure is applied to the inner surface of the tunnel lining model 4, thereby simulating the effect of internal water pressure applied to the inner wall of the tunnel. Step 4-3: After holding the pressure for 5-10 minutes, conduct a test experiment on the physical model device of the tunnel lining model.

[0062] Because the transparent rubber airbag 11 is made of transparent material, in the tunnel physical model test, only wiring holes need to be reserved on the water supply pipe to provide a routing path for the cables of various sensors. The external deformation and failure characteristics of the tunnel lining model can be observed and recorded through the transparent rubber airbag. Sensors inside the tunnel can observe the internal deformation and failure of the tunnel lining structure model, as well as the stress on the lining, providing a more intuitive understanding of the mechanical response law and deformation and failure characteristics of the surrounding rock-lining structure of the water diversion tunnel.

[0063] The above description is only a preferred embodiment of the present invention. It should be noted that any improvements made by those skilled in the art without departing from the principle of the present invention should also be within the protection scope of the present invention.

[0064] In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0065] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art will understand the specific meaning of the above terms in this application based on the specific circumstances.

Claims

1. A physical model device for simulating the confining pressure and internal water pressure of a water diversion tunnel, characterized in that, include: Confining pressure loading device (1), internal water pressure loading device (2), base (3) and tunnel lining model (4); The confining pressure loading device (1) applies air pressure to the outer surface of the tunnel lining model (4), the internal water pressure loading device (2) applies water pressure to the inner surface of the tunnel lining model (4), and the base (3) is used to fix the tunnel lining model (4). The confining pressure loading device (1) includes a transparent rubber airbag (11), a hollow threaded tie rod (12), a stainless steel hollow frame (13), an air guide pipe (14), an air inlet valve (15), and an electric air pump (16). The transparent rubber airbag (11) is used to cover the outer wall of the tunnel lining model (4). It is a circular cylinder made of transparent rubber with an inner wall and an outer wall. There is a gas chamber between the inner wall and the outer wall. Multiple flexible sealing air connectors are arranged in an array on the outer wall. The flexible sealing air connectors are connected to the gas chamber. The stainless steel hollow frame (13) is a hollow structure with multiple air outlets on its inner side wall and air inlets on its outer side wall. The hollow threaded tie rod (12) is used to provide a gas channel for the flexible sealing air inflatable joint and to provide radial support for the tunnel lining model (4). Its axial length is adjustable. One end is connected to the flexible sealing air inflatable joint of the transparent rubber airbag (11), and the other end is connected to the air outlet of the stainless steel hollow frame (13). The air inlet valve (15) is provided with an air outlet connection column and an air inlet connection column; An electric air pump (16) is used to provide air to the transparent rubber airbag (11). The electric air pump (16) is connected to the air inlet connection post of the air inlet valve (15) through the air guide pipe (14). The air outlet connection post of the air inlet valve (15) is connected to the air inlet of the stainless steel hollow frame (13) through the air guide pipe (14). The internal water pressure loading device (2) includes a perforated gasket (21), an inlet valve (22), a water supply pipe (23), a water pump (24), a rubber sleeve (25), and a hoop (26). The cross-sectional shape and size of the perforated gasket (21) are adapted to the cross-sectional shape and size of the tunnel lining model (4). Its lower end is placed on the upper end surface of the tunnel lining model (4), and its upper end is welded to the water inlet valve (22). A rubber sleeve (25) is fitted at the connection with the tunnel lining model (4). Two hoop rings (26) are provided on the outer surface of the rubber sleeve (25). The base (3) includes a first groove (31) for fixing a stainless steel hollow frame (13) and a second groove (32) for fixing a tunnel lining model (4), wherein a plug (33) for sealing the lower opening of the tunnel lining model (4) is glued and fixed in the second groove (32).

2. The physical model device for simulating the confining pressure and internal water pressure of a water diversion tunnel according to claim 1, characterized in that, The hollow threaded tie rod (12) includes a plurality of sub-threaded tie rods connected in sequence; During assembly, all connections between the air inlet of the air pipe (14) and the air inlet of the stainless steel hollow frame (13), the connection between the air inlet of the air pipe (14) and the air inlet connecting column of the air inlet valve (15), the connection between the hollow threaded tie rod (12) and the flexible sealing inflation joint of the transparent rubber airbag (11), the connection between the air outlet of the stainless steel hollow frame (13) and the hollow threaded tie rod (12), and the connection between each section of the threaded tie rod are firmly bonded with high-strength adhesive, and a sealing strip is wrapped around the outer periphery of the interface for secondary sealing treatment.

3. The physical model device for simulating the confining pressure and internal water pressure of a water diversion tunnel according to claim 2, characterized in that, The stainless steel hollow frame (13) is a hollow square ring. The stainless steel hollow frame (13) is used to provide a gas channel and support point for the hollow threaded tie rod (12). There are 4 air outlets in each layer, which are respectively set at the four inner corners of the square ring. There are a total of 6 layers along the height direction of the stainless steel hollow frame (13). There is an air inlet on each of the four outer walls of the stainless steel hollow frame (13). The outer wall of the transparent rubber airbag (11) has four flexible sealing inflation joints evenly distributed radially in each layer, and a total of six layers evenly distributed axially in the outer wall of the transparent rubber airbag (11).

4. The physical model device for simulating the confining pressure and internal water pressure of a water diversion tunnel according to claim 3, characterized in that, The stainless steel hollow frame (13) adopts a hollow square ring with a hollow structure and hollow holes on the side wall.

5. A physical model device for simulating the confining pressure and internal water pressure of a water diversion tunnel as described in claim 3 or 4, and a method for assembling and using the physical model device for simulating the confining pressure and internal water pressure of a water diversion tunnel, characterized in that... Includes the following steps: Step 1: Equipment preparation: Based on the determined axial length of the tunnel lining model (4) and the thickness of the perforated gasket (21), prepare a stainless steel hollow frame (13) and a circular cylindrical transparent rubber airbag (11) according to the predetermined axial dimensions, so that the transparent rubber airbag (11) is evenly wrapped around the outer wall of the tunnel lining model (4). Step 2: Assembly of the confining pressure loading device (1) Step 2-1: Pre-pressurize and check the airtightness of the transparent rubber airbag (11). If the airtightness meets the requirements, proceed to the next step. Step 2-2: Assembly between the transparent rubber airbag (11), the tunnel lining model (4), and the base (3). First, the transparent rubber airbag (11) is wrapped around the outer wall of the tunnel lining model (4); then the tunnel lining model (4) wrapped with the transparent rubber airbag (11) is inserted into the groove of the plug (33) in the second groove (32) of the base (3); finally, the stainless steel hollow frame (13) is inserted into the first groove (31). Steps 2-3: Connection between the transparent rubber airbag (11) and the stainless steel hollow frame (13) First, adjust the length of the hollow threaded rod (12) according to the gap between the transparent rubber airbag (11) and the stainless steel hollow frame (13); then connect all the hollow threaded rods (12) to the flexible sealing inflation joint of the transparent rubber airbag (11) and the air outlet of the stainless steel hollow frame (13), and ensure that the length of each hollow threaded rod is consistent in the device. Steps 2-4: Airtight treatment of hollow threaded tie rod (12) At the joint between the hollow threaded tie rod (12) and the transparent rubber airbag (11), at the joint between the stainless steel hollow frame (13) and the hollow threaded tie rod (12), and at the connection between each segment of the threaded tie rod, a high-strength adhesive is used to firmly bond them together, and a sealing strip is wrapped around the outer periphery of the interface for secondary sealing treatment. Steps 2-5: Piping and Equipment Installation Use an air guide tube (14) to connect the air intake connection post of the air intake valve (15) and the air outlet connection post of the electric air pump (16); Use an air guide tube (14) to connect the air outlet connection column of the air inlet valve (15) to the air inlet of the stainless steel hollow frame (13); Steps 2-6: Airtightening of Pipelines Use strong adhesive to seal and bond the pipe connections, and then seal the joints with sealing strips. Step 3: Assembly of the internal water pressure loading device (2): Step 3-1: The upper end of the perforated gasket (21) is welded to the water inlet valve (22) as a whole; Step 3-2: Place the lower end of the perforated gasket (21) in the internal water pressure loading device on the tunnel lining model (4), and then wrap the connection with a transparent rubber airbag (11); Step 3-3: A rubber sleeve (25) is put on the connection between the perforated gasket (21) and the tunnel lining model (4). Two hoop rings (26) are provided on the outer surface of the rubber sleeve (25). One hoop ring (26) is hooped on the water inlet valve (22), and the other hoop ring (26) is hooped on the tunnel lining model (4), so that the perforated gasket (21) and the tunnel lining model (4) are in close contact and connected. Steps 3-4: Connect the water supply pipe (23) between the water pump (24) and the inlet valve (22); Steps 3-5: Use strong adhesive to bond the connection between the water inlet valve (22), the water supply pipe (23) and the water pump (24), and use a sealing strip to seal the bonded joints a second time; Step 4, Applying confining pressure and internal water pressure: Based on the confining pressure and internal water pressure values ​​required for the tunnel physical model test, proceed with steps 4-1 and 4-2 simultaneously; Step 4-1: Start the electric air pump (16) to deliver gas through the air pipe (14), through the air inlet valve (15), through the stainless steel hollow frame (13), and then through the hollow threaded tie rod (12) to the transparent rubber airbag (11) until the pressure display (17) shows that the air pressure inside the transparent rubber airbag (11) has been loaded to the set confining pressure value. Then turn off the electric air pump (16), and the transparent rubber airbag (11) will inflate and expand. Its inner wall will squeeze the outer wall of the tunnel lining model (4), thereby simulating the effect of confining pressure applied to the outer wall of the tunnel. Step 4-2: Start the water pump (24) to send water through the water pipe (23) and inlet valve (22), and then through the perforated gasket (21) into the tunnel lining model (4) until the water pump (24) pressure display shows that the internal water pressure in the tunnel lining model (4) has been loaded to the set water pressure value. Then turn off the water pump (24). At this time, the set water pressure is applied to the inner surface of the tunnel lining model (4), thereby simulating the effect of internal water pressure applied to the inner wall of the tunnel. Step 4-3: After holding the pressure for 5-10 minutes, conduct a test experiment on the physical model device of the tunnel lining model.

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