Test device for simulating subway station excavation under influence of existing tunnel and excavation method

Abstract

The invention discloses a test device for simulating subway station excavation under the influence of an existing tunnel and an excavation method. The test device comprises a model box, and a station simulation structure, an existing tunnel simulation structure and data monitoring and acquisition equipment which are arranged in the model box. The existing tunnel simulation structure is arranged above the station simulation structure, and the model box and the inner space of the station simulation structure are filled with test soil. The data monitoring and collecting equipment is assembled on the station simulation structure, the existing tunnel simulation structure and the surface layer position of the test soil body. The invention further discloses an excavation method for excavating the subway station based on the experimental device, and the stress-strain and displacement rules of the subway station and the existing tunnel in the subway station excavated by the underground excavation arch cover method under the influence of the existing tunnel in a complex environment are analyzed and researched. And reference is further provided for optimization of the design and construction scheme of excavation of the subway station through the arch cover method and the underground excavation arch cover method for penetrating through the existing tunnel in the complex environment.

Description

Technical Field

[0001] The invention relates to the technical field of subway station excavation, in particular to a test device and an excavation method for simulating the excavation of a subway station under the influence of an existing tunnel. Background Art

[0002] When subway stations are constructed using the dark excavation method, they usually have the characteristics of large tunnel section excavation, shallow tunnel burial depth, large upper surface load, complex surrounding rock geological conditions, high requirements for tunnel settlement, and greater difficulty in excavation operations. During the excavation process, it is inevitable that it will be affected by existing buildings (structures). In response to the above-mentioned dark excavation characteristics, the dark excavation method for subway stations still has many difficulties.

[0003] By designing model tests and methods, we can effectively simulate and study the influence of existing tunnels on the process of subway station excavation by the dark-cut arch-cover method in complex environments. By collecting, processing and analyzing the test data, we can obtain the relevant physical laws of the influence of existing tunnels on subway station excavation in complex environments, and further study the dark-cut arch-cover method. As far as the current industry level is concerned, there is a lack of research on model tests and methods for the dark-cut arch-cover method of subway station excavation under the influence of existing tunnels.

[0004] Therefore, for the underground project of subway stations excavated by the arch cover method through existing buildings (structures), an experimental device and excavation method that simulates the underground excavation of subway stations under the influence of existing tunnels are designed, and the changes in relevant physical laws during the excavation process are studied to help analyze the stress, strain and displacement laws of the subway station construction site and the existing tunnel, and further provide reference for the optimization of the design and construction plan of subway stations excavated by the arch cover method under the influence of existing tunnels. Summary of the invention

[0005] In view of the above-mentioned deficiencies in the prior art, the purpose of the present invention is to provide a test device and an excavation method for simulating the excavation of a subway station under the influence of an existing tunnel, to analyze and study the stress, strain and displacement laws of the subway station and the existing tunnel in the subway station excavated by the dark excavation and arch cover method under the influence of the existing tunnel in a complex environment, and to further provide a reference for the optimization of the design and construction plan of the dark excavation and arch cover method for excavating a subway station through existing buildings (structures) in a complex environment.

[0006] The technical solution adopted by the present invention to achieve the above-mentioned purpose is: a test device for simulating the excavation of a subway station under the influence of an existing tunnel, including a model box and a station simulation structure, an existing tunnel simulation structure, and data monitoring and collection equipment arranged in the model box.

[0007] The existing tunnel simulation structure is arranged above the station simulation structure, and the model box and the internal space of the station simulation structure are filled with test soil.

[0008] The data monitoring and collection equipment is installed at the station simulation structure, the existing tunnel simulation structure and the surface position of the test soil body.

[0009] In some of the implementations, in order to ensure the structural stability of the model box itself, ensure that the station simulation structure, the existing tunnel simulation structure and the data detection and acquisition equipment can be stably installed in the model box, and conduct experiments to simulate the excavation of the subway station by the dark excavation and arch cover method under the influence of the existing tunnel, the following technical solutions are provided.

[0010] The model box includes a bottom support, a support frame, and a retaining structure. The support frame is fixedly connected to the bottom support. The support frame is formed by splicing and fixing vertical steel beams, transverse steel beams, and top steel beams. The retaining structure is arranged on the periphery of the support frame.

[0011] In some of the implementations, in order to ensure that the retaining structure in the model box can be stably installed on the supporting frame and to ensure that the retaining structure can achieve its designed function, the following technical solutions are provided.

[0012] The supporting structure includes a front baffle, a back baffle, and a side baffle. The front baffle and the back baffle are respectively fixedly connected to the front and back of the supporting frame, and the side baffle is fixedly connected to the two side surfaces of the supporting frame.

[0013] The front baffle and the back baffle are made of organic glass plates. An operation opening is provided on the front baffle, and a supporting baffle is arranged outside the operation opening.

[0014] In some of the implementations, in order to make the simulated excavation work of the subway station as close as possible to the actual on-site construction and to ensure that the simulated structure of the station can fully simulate the structure of the subway station, the following technical solutions are provided.

[0015] The station simulation structure includes an arch structure, a vertical pile structure, and a lining structure. Two groups of supporting structures arranged side by side are installed on the inner side of the arch structure, and the supporting structure divides the internal space of the arch structure into a central guide tunnel and a left side guide tunnel and a right side guide tunnel on both sides of the central guide tunnel; the lining structure includes a bottom lining and side linings connected to both sides of the bottom lining and arranged in a vertical direction, and the top of the side lining is connected to the bottom of the arch structure; the vertical pile structure is supported on the bottom lining and maintains abutment with the supporting structure.

[0016] In some of the implementations, in order to ensure the structural stability of the existing tunnel simulation structure itself and to ensure that it can accurately simulate the impact of the existing tunnel on the subway station excavation operation, the following technical solutions are provided.

[0017] The existing tunnel simulation structure includes a pipeline structure, a port baffle, and a connecting gasket. The pipeline structure includes multiple sections that are butt-jointed end to end. Two connected sections of the pipeline structure are fixedly connected by a connecting gasket and bolts that penetrate the connecting gasket and are screwed to the pipeline structure. The port position of the outermost pipeline structure is blocked with a port baffle.

[0018] In some of the implementations, in order to simulate the influence of the vibration generated during the passage and operation of the existing tunnel on the excavation of the subway station when excavating the subway station, the following technical solutions are provided.

[0019] A vibration simulation device can be installed in the existing tunnel simulation structure, and the vibration simulation device includes an assembly column, a telescopic sleeve, a vibration component, a retractable component, and an adjustment component. The assembly column is assembled in the pipeline structure, the telescopic sleeve is slidably inserted at both ends of the assembly column, the vibration component is rotatably installed in the telescopic sleeve, the retractable component is assembled in the assembly column and keeps linkage with two sets of telescopic sleeves, and the adjustment component keeps linkage with the vibration component.

[0020] In some of the implementations, in order to ensure that the retractable assembly can be stably installed on the assembly column and to achieve synchronous adjustment of the retractable and retractable postures of the two sets of telescopic sleeves, the following technical solutions are provided.

[0021] The retractable assembly includes a driving shaft and an adjusting screw. The driving shaft is rotatably installed in the assembly column and arranged in the radial direction. An operating knob is fixedly connected to the end of the driving shaft, and the operating knob is arranged on the outside of the assembly column. The adjusting screw is rotatably installed in the assembly column and arranged in the axial direction. The inner end of the telescopic sleeve is rotationally connected to the adjusting screw. A driving bevel gear is fixedly connected to the driving shaft, and a transmission bevel gear meshing with the driving bevel gear is fixedly connected to the inner end of the adjusting screw.

[0022] In some of the implementations, in order to ensure that the vibration assembly can be stably installed in the telescopic sleeve and that the vibration assembly can generate a vibration force of a specific magnitude and direction, the following technical solutions are provided.

[0023] The vibration assembly includes an assembly disk, a counterweight slide, a rotating seat, and a connecting rod. The assembly disk is rotatably installed in the telescopic sleeve. The assembly disk is provided with a radially arranged guide groove. The counterweight slide is slidably installed in the guide groove. The counterweight slide is provided with a clearance hole. The rotating seat is rotatably installed at the axis of the assembly disk and is arranged in the clearance hole. The two ends of the connecting rod are respectively hinged with the outer edge of the rotating seat and the counterweight slide, and the adjustment assembly is linked with the assembly disk and the rotating seat.

[0024] In some of the implementations, in order to ensure that the adjustment component is effectively assembled in the assembly column and the telescopic sleeve, and to ensure that the adjustment component can adjust the operating posture of the assembly disk and the rotating seat, the following technical solutions are provided.

[0025] The adjustment component includes a driving motor, a spline shaft, a spline sleeve, and a ratchet mechanism. The driving motor is fixedly installed in the assembly column and maintains a power connection with the spline shaft. The spline shaft is provided with two groups arranged along the axial direction of the assembly shaft. The spline sleeve is slidably plugged into the spline shaft. The spline sleeve is power-connected with two groups of ratchet mechanisms arranged in the same direction. The assembly disk and the rotating seat respectively maintain a power connection with the two groups of ratchet mechanisms.

[0026] In some of the implementations, in order to ensure that the data monitoring and acquisition equipment can be installed with the station simulation structure, the existing tunnel simulation structure and the filled test soil, and effectively monitor the displacement, stress and strain data during the excavation test, the following technical solutions are provided.

[0027] The data monitoring and acquisition equipment includes a telescopic displacement meter, a dial indicator, a strain gauge, and an earth pressure box. The telescopic displacement meter is arranged above the arch structure and above the existing tunnel simulation structure, and the telescopic displacement meter maintains contact with the arch structure or the existing tunnel simulation structure. The dial indicator is arranged on the surface of the experimental soil, and the strain gauge is pasted on the top of the arch structure and the bottom of the existing tunnel simulation structure. The earth pressure box is arranged at the center of the top of the arch structure, the arch foot position of the arch structure, and the bottom of the existing tunnel simulation structure, and the earth pressure box maintains contact with the arch structure or the existing tunnel simulation structure.

[0028] According to the above-mentioned test device for simulating the excavation of a subway station under the influence of an existing tunnel, an excavation method is provided, which has the following steps:

[0029] S1, simulated formation configuration:

[0030] According to the size conditions of the model box, the geometric similarity ratio between the model size and the on-site prototype size is determined to be 1:L. The model size is designed as 1 / L of the prototype size, and the test soil filled in the model box is designed according to the geometric similarity ratio. The parameters of the test soil comply with the following requirements:

[0031] Geometric similarity ratio: CL = 1;

[0032] Similarity ratios of gravity, internal friction angle and Poisson’s ratio: CY = Cφ = Cμ = 1;

[0033] Similarity ratio of elastic modulus and cohesion: CE = Cc = 1 / L;

[0034] Permeability coefficient similarity ratio: CK = 1 / √L;

[0035] S2: Model structure, arrangement of data monitoring and acquisition equipment, and filling of model boxes:

[0036] According to the positional relationship of the station simulation structure, the existing tunnel simulation structure, and the data monitoring and acquisition equipment in the model box, they are arranged from bottom to top, and the test soil is filled in the gaps;

[0037] S3, excavation process simulation:

[0038] Operate the operating openings on the model box to simulate excavation of the test soil within the station simulation structure;

[0039] S3-1, first working cycle:

[0040] The excavation on the left side of the central guide tunnel is divided into four horizontal excavation stages. After each stage is completed, the arch cover on the left side of the central guide tunnel is lined with concrete for the second time. After the concrete lining strength meets the requirements, the next stage of excavation is carried out;

[0041] S3-2, the second working cycle:

[0042] The excavation on the right side of the central guide tunnel is divided into four horizontal excavation stages. After each stage is completed, the arch cover part on the right side of the central guide tunnel is lined with concrete for the second time. After the concrete lining strength meets the requirements, the next stage of excavation is carried out;

[0043] S3-3, the third working cycle:

[0044] The left side guide tunnel was excavated and advanced in four horizontal excavation stages. After each stage was completed, the arch cover of the left side guide tunnel was lined with concrete for the second time. The next stage of excavation was carried out after the concrete lining strength met the requirements.

[0045] S3-4, the fourth working cycle:

[0046] The right side guide tunnel was excavated and advanced in four horizontal excavation stages. After each stage was completed, the arch cover of the right side guide tunnel was lined with concrete for the second time. The next stage of excavation was carried out after the concrete lining strength met the requirements.

[0047] S3-5, Removal of supporting structures:

[0048] After the middle guide tunnel, the left side guide tunnel and the right side guide tunnel are completely penetrated, the supporting structure is dismantled and the top of the vertical pile structure is connected with the arch part with concrete to replace the supporting structure and serve as a vertical supporting column to bear the arch structure and upper load;

[0049] S3-6, station space simulation excavation:

[0050] After the excavation and lining of the arch structure are completed and the overall structure is stable, the station space is simulated excavated according to the step method in the subway excavation method. It is divided into two excavation cycles, left and right. Each excavation cycle is divided into four excavation advance stages in the horizontal direction. After each excavation is completed, the lining structure is relined with concrete.

[0051] S3-7, data analysis and processing:

[0052] In each stage of steps S3-1 to S3-6, the data monitoring and acquisition equipment processes the monitoring data in real time and draws the displacement-excavation stage curve comparison, the earth pressure-excavation stage curve comparison and the strain-excavation process stage curve of the corresponding excavation stage;

[0053] By analyzing the data curve, the settlement law of the arch structure, the stress-strain law of the surrounding rock and the change law of the upper load of the underground subway station under the influence of the existing tunnel are obtained, and guidance is provided for the design and construction plan of the subway station under the influence of the existing tunnel in the actual project.

[0054] Beneficial effects of the present invention:

[0055] 1. The present invention designs and manufactures a test device and excavation method for simulating the excavation of a subway station by the dark-cut arch-cover method under the influence of an existing tunnel, and carries out excavation work after the model design and manufacture is completed, and analyzes and studies the stress, strain and displacement laws of the subway station and the existing tunnel in the dark-cut arch-cover method excavation of the subway station under the influence of the existing tunnel in a complex environment.

[0056] 2. The present invention simulates the confining pressure stress generated by the surrounding environment and existing strata during subway excavation in a complex environment through external constraints of the model box, including vertical and transverse steel beams, surrounding retaining structures, bottom supports and internally filled test soil, which fully simulates the actual excavation environment on site and is more conducive to the research and analysis of the specific process.

[0057] 3. The present invention uses multi-section connected PVCC pipes to simulate the excavation of an existing tunnel above a subway station, simulating the upper stress generated by the upper existing buildings (structures) during subway excavation in a complex environment, fully restoring the existence of actual existing structures on site, and is more conducive to the analysis of the physical laws of the specific process of actual construction.

[0058] 4. Based on the problem that it is difficult to design a simulation test for subway stations excavated by the dark-cut arch-cover method due to the influence of existing buildings (structures) in complex environments, the present invention innovatively pre-buries the station simulation structure and the existing tunnel simulation structure when filling the simulated stratum, which greatly improves the operability of the test and reduces the time for simulated support construction lining.

[0059] 5. The data monitoring and acquisition equipment in the present invention is pre-arranged in the relevant parts of the station simulation structure and the existing tunnel simulation structure when filling the simulated stratum, which effectively simulates the on-site monitoring environment and reduces the operation time of the model test and the workload of subsequent analysis and processing.

[0060] 6. By designing a vibration simulation device, it is possible to simulate the state and vibration of existing tunnels with passing vehicles, ensure the diversity and accuracy of collected data, and better simulate the on-site environment of subway construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 It is a structural schematic diagram of the present invention;

[0062] Figure 2 This is a schematic diagram of the structure of the present invention after removing the retaining structure;

[0063] Figure 3 It is a structural diagram of the simulated structure of the station;

[0064] Figure 4 It is a structural schematic diagram of the existing tunnel simulation structure;

[0065] Figure 5 It is a structural schematic diagram of a vibration simulation device;

[0066] Figure 6 It is a schematic diagram of the internal structure of the vibration simulation device;

[0067] Figure 7 It is a structural diagram of the combination of the vibration component, the adjustment component, and the retractable component;

[0068] Figure 8 is a schematic diagram of the structure of the vibration component;

[0069] Fig. 9 is a schematic diagram of the structure of the ratchet mechanism;

[0070] Fig.10 Schematic diagram of the arrangement of earth pressure cell;

[0071] Fig.11 It is a schematic diagram of the arrangement of the telescopic displacement meter and the dial indicator;

[0072] Fig.12 Schematic diagram of the strain gauge arrangement.

[0073] In the figure: 1 model box, 11 bottom support, 12 support frame, 121 vertical steel beam, 122 horizontal steel beam, 123 top steel beam, 131 front baffle, 1311 operating opening, 132 back baffle, 133 side baffle, 2 station simulation structure, 21 arch structure, 211 support structure, 212 middle guide hole, 213 left side guide hole, 214 right side guide hole, 22 vertical pile structure, 23 lining structure, 3 existing tunnel simulation structure, 31 pipeline structure, 32 port baffle, 33 connection gasket, 41 telescopic displacement meter, 42 dial indicator, 43 strain gauge, 44 earth pressure box, 51 assembly column, 52 telescopic sleeve, 521 assembly cover, 53 vibration assembly, 531 assembly disk, 531 guide groove, 532 counterweight slide, 5321 give way through hole, 533 rotating seat, 534 connecting rod, 54 retractable assembly, 541 drive shaft, 5411 operating knob, 5412 drive bevel gear, 542 adjusting screw, 5421 drive bevel gear, 55 adjustment assembly, 551 drive motor, 5511 drive seat, 552 spline shaft, 553 spline sleeve, 554 ratchet mechanism, 5541 drive seat, 5542 drive shaft, 5543 pawl, 5544 inner ratchet. DETAILED DESCRIPTION

[0074] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0075] Example 1

[0076] Please refer to the figure, which shows a test device for simulating the excavation of a subway station under the influence of an existing tunnel, including a model box 1, a station simulation structure 2 arranged in the model box 1, an existing tunnel simulation structure 3, and data monitoring and collection equipment.

[0077] The existing tunnel simulation structure 3 is arranged above the station simulation structure 2 , and the model box 1 and the inner space of the station simulation structure 2 are filled with test soil.

[0078] The data monitoring and acquisition equipment is installed at the station simulation structure 2, the existing tunnel simulation structure 3 and the surface of the test soil.

[0079] The test soil is used to simulate the layer structure and characteristics of the subway station construction site. The station simulation structure 2 is supported and excavated according to the dark-cut arch-cover excavation method, and its related processes are monitored in real time through data monitoring and acquisition equipment; the existing tunnel simulation structure 3 is used to simulate the existing tunnel above the actual subway station, and the impact on the existing tunnel during the excavation process is monitored in real time through the arranged data detection and acquisition equipment.

[0080] Example 2

[0081] See also Figure 1-2 In order to ensure the structural stability of the model box 1 itself, ensure that the station simulation structure 2, the existing tunnel simulation structure 3 and the data detection and acquisition equipment can be stably installed in the model box 1, and conduct experiments on excavating the subway station by the dark excavation and arch cover method under the influence of the existing tunnel, the following technical solutions are provided.

[0082] The model box 1 includes a bottom support 11, a support frame 12, and a retaining structure. The support frame 12 is fixedly connected to the bottom support 11. The support frame 12 is formed by splicing and fixing a vertical steel beam 121, a horizontal steel beam 122, and a top steel beam 123. The retaining structure is arranged on the periphery of the support frame 12.

[0083] The model box 1 is a roughly rectangular box structure, wherein the bottom support 11 is made of thick steel plate, the periphery of the bottom support 11 is wrapped with channel iron, and is fixed and spliced ​​by welding to facilitate connection with the upper structure.

[0084] The vertical steel beams 121 are vertically distributed using channel steels, and there are eight groups in total. They are arranged at the four corners and the front and back sides of the bottom support 11, and are spliced ​​and fixed to the bottom support 11 by welding.

[0085] The transverse steel beam 122 is distributed transversely using channel steel, spliced ​​between the vertical steel beams 121, arranged at a certain interval on the front and back, and spliced ​​and fixed to the vertical steel beams 121 by welding. The overall structure of the transverse steel beam 122 and the vertical steel beam 121 cooperates with the supporting structure to provide stable support and restraint for the filler inside the model box 1.

[0086] The top steel beam 123 is made of channel steel, assembled and welded in a horizontal and vertical cross manner, and is fixedly connected to the top cross beam by punching holes with an impact drill and fixing with bolts.

[0087] The main function of the top steel beam 123 is to fix the data monitoring and acquisition equipment, and the quick disassembly function is realized by bolting the shell.

[0088] See also Figure 1In order to ensure that the retaining structure in the model box 1 can be stably installed on the supporting frame 12 and to ensure that the retaining structure can achieve its designed function, the following technical solution is provided.

[0089] The supporting structure includes a front baffle 131 , a back baffle 132 , and a side baffle 133 . The front baffle 131 and the back baffle 132 are fixedly connected to the front and back of the supporting frame 12 , respectively, and the side baffle 133 is fixedly connected to the two side surfaces of the supporting frame 12 .

[0090] The front baffle 131 and the back baffle 132 are made of organic glass plates. An operation opening 1311 is provided on the front baffle 131 , and a supporting baffle is installed outside the operation opening 1311 .

[0091] Holes are drilled on the front baffle 131, the back baffle 132 and the corresponding transverse steel beams 122 and the vertical steel beams 121 by an impact drill, and the front baffle 131 and the back baffle 132 are fixed to the supporting frame 12 by bolts. Their main function is to support the filler inside the model box 1 and to facilitate the observation of the layout and positioning of subsequent components.

[0092] The operation opening 1311 is set to be rectangular and is cut by a cutting machine to reserve operation and excavation space for subsequent excavation of the subway station.

[0093] One set of side baffles 133 is made of steel plate and fixedly spliced ​​with the vertical steel beam 121 by welding. Another set of side baffles 133 is supported by plywood and fixedly spliced ​​with the vertical steel beam 121 by drilling holes with an impact drill and fixing with bolts.

[0094] When the side baffles 133 are made of steel plates, they support the filling inside the model box 1. When the side baffles 133 are made of plywood, they support the internal filling and fill the test soil on the next side.

[0095] Example 3

[0096] See also Figure 3 In order to make the simulated excavation work of the subway station as close to the actual construction on site as possible and to ensure that the station simulation structure 2 can fully simulate the structure of the subway station, the following technical solutions are provided.

[0097] The station simulation structure 2 includes a vault structure 21, a vertical pile structure 22, and a lining structure 23. Two groups of supporting structures 211 arranged side by side are installed on the inner side of the vault structure 21. The supporting structure 211 divides the internal space of the vault structure 21 into a middle guide tunnel 212 and a left side guide tunnel 213 and a right side guide tunnel 214 on both sides of the middle guide tunnel 212; the lining structure 23 includes a bottom lining and side linings connected to both sides of the bottom lining and arranged in a vertical direction, and the top of the side lining is connected to the bottom of the vault structure 21; the vertical pile structure 22 is supported on the bottom lining and maintains contact with the supporting structure 211.

[0098] The arch structure 21 is an arch structure formed by overlapping stainless steel plates. The middle guide hole 212, the left side guide hole 213, and the right side guide hole 214 inside the arch structure are filled with plaster or concrete to simulate the arch support and protection structure part during the excavation process of the subway station.

[0099] The support structure 211 is arranged below the arch structure 21 and is composed of wooden boards, and is used to simulate the preliminary support partition wall below the arch support protection structure part during the excavation process of the subway station.

[0100] The vertical pile structure 22 is formed by a circular steel pipe filled with gypsum, and is used to simulate the vertical support column for bearing the vault and upper load after the subway station is excavated.

[0101] The lining structure 23 is formed by combining templates and is used to simulate the lining protection on both sides during the excavation of a subway station.

[0102] See also Figure 4 In order to ensure the structural stability of the existing tunnel simulation structure 3 and ensure that it can accurately simulate the impact of the existing tunnel on the subway station excavation operation, the following technical solutions are provided.

[0103] The existing tunnel simulation structure 3 includes a pipeline structure 31, a port baffle 32, and a connecting gasket 33. The pipeline structure 31 includes multiple sections connected end to end. The two connected sections of the pipeline structure 31 are fixedly connected by a connecting gasket 33 and bolts that penetrate the connecting gasket 33 and are screwed to the pipeline structure 31. The port position of the outermost pipeline structure 31 is blocked with a port baffle 32.

[0104] The pipe structure 31 is made of a PVC pipe with a certain strength, and the connection gasket 33 is fitted with the adjacent two ends of the pipe structure 31, and the two sections of the pipe are spliced ​​and fixed by bolts. The port baffle 32 is cut from a wooden board and glued to the edge port position of the pipe structure 31 to achieve the blocking of the existing tunnel simulation structure 3 and prevent the filled test soil from invading the existing tunnel simulation structure 3 and affecting the accuracy of the simulated excavation test.

[0105] Example 4

[0106] See also Figure 5-9 In order to simulate the influence of the vibration generated during the passage and operation of the existing tunnel on the excavation of the subway station when excavating the subway station, the following technical solutions are provided.

[0107] A vibration simulation device can be installed in the existing tunnel simulation structure 3, and the vibration simulation device includes an assembly column 51, a telescopic sleeve 52, a vibration component 53, a retractable component 54, and an adjustment component 55. The assembly column 51 is assembled in the pipeline structure 31, the telescopic sleeve 52 is slidably inserted at both ends of the assembly column 51, the vibration component 53 is rotatably installed in the telescopic sleeve 52, the retractable component 54 is assembled in the assembly column 51 and keeps linkage with the two sets of telescopic sleeves 52, and the adjustment component 55 keeps linkage with the vibration component.

[0108] An assembly cover 521 is fixedly connected to the outer end of the telescopic sleeve 52 by bolts, and the vibration component 53 is placed on the inner side of the assembly cover 521. The arrangement of the assembly cover 521 facilitates the disassembly, assembly and maintenance of the vibration component 53 in the telescopic sleeve 52. The assembly column 51 and the assembly cover 521 are kept in contact with the inner wall of the pipeline structure 31. The vibration force generated by the operation of the vibration component 53 can be stably transmitted to the existing tunnel simulation mechanism to simulate the vibration generated by vehicles passing through the existing tunnel.

[0109] The adjustment component 55 can adjust the magnitude and direction of the vibration force of the vibration component 53, and the retractable component 54 can adjust the length of the vibration simulation device, so that multiple groups of vibration simulation devices can be connected end to end to fill the existing tunnel simulation structure 3.

[0110] In some of the implementations, in order to ensure that the retractable assembly 54 can be stably installed on the assembly column 51 and to achieve synchronous adjustment of the retractable and retractable postures of the two sets of telescopic sleeves 52, the following technical solutions are provided.

[0111] The retracting and extending assembly 54 includes a driving shaft 541 and an adjusting screw 542. The driving shaft 541 is rotatably installed in the assembly column 51 and is arranged in the radial direction. An operating knob 5411 is fixedly connected to the end of the driving shaft 541. The operating knob 5411 is arranged on the outside of the assembly column 51. The adjusting screw 542 is rotatably installed in the assembly column 51 and is arranged in the axial direction. The inner end of the telescopic sleeve 52 is rotationally connected to the adjusting screw 542. A driving bevel gear 5412 is fixedly connected to the driving shaft 541. The inner end of the adjusting screw 542 is fixedly connected to a transmission bevel gear 5421 that meshes with the driving bevel gear 5412.

[0112] A hexagonal groove is provided on the operating knob 5411, which is convenient for rotating the drive shaft 541 by twisting it with a hexagonal wrench, and then driving the adjusting screw 542 to rotate through the combination of the driving bevel gear 5412 and the transmission bevel gear 5421. There are four groups of adjusting screws 542 in total, and each group of telescopic sleeves 52 is screwed with two groups of adjusting screws 542 to drive each group of telescopic sleeves 52 to stably retract and extend along the axial direction of the assembly column 51.

[0113] In order to ensure that the vibration assembly 53 can be stably installed in the telescopic sleeve 52 and to ensure that the vibration assembly can generate a vibration force of a specific size and direction, the following technical solution is provided.

[0114] The vibration assembly 53 includes an assembly disk 531, a counterweight slide 532, a rotating seat 533, and a connecting rod 534. The assembly disk 531 is rotatably installed in the telescopic sleeve 52. The assembly disk 531 is provided with a radially arranged guide groove 5311. The counterweight slide 532 is slidably installed in the guide groove 5311. The counterweight slide 532 is provided with a clearance hole 5321. The rotating seat 533 is rotatably installed at the axis of the assembly disk 531 and is arranged in the clearance hole 5321. The two ends of the connecting rod 534 are respectively hinged with the outer edge of the rotating seat 533 and the counterweight slide 532. The adjustment assembly 55 is linked with the assembly disk 531 and the rotating seat 533.

[0115] By driving the assembly disk 531 to rotate as a whole, the counterweight slide 532 can be rotated synchronously to adjust the orientation angles of the guide groove 5311 and the counterweight slide 532, thereby achieving adjustment of the direction of the vibration force.

[0116] By driving the rotating seat 533 to operate, the counterweight slide 532 can be driven to reciprocate in the guide groove 5311 through the connecting rod 534, and the inertia force of the counterweight slide 532 generates a vibration force along the length direction of the guide groove 5311. The vibration force acts on the existing tunnel simulation structure 3 through the assembly disk 531 and the telescopic sleeve 52 to simulate the vibration generated during the operation of the existing tunnel.

[0117] In order to ensure that the adjustment component 55 is effectively assembled in the assembly column 51 and the telescopic sleeve 52, and to ensure that the adjustment component 55 can adjust the operating posture of the assembly disk 531 and the rotating seat 533, the following technical solution is provided.

[0118] The adjustment component 55 includes a drive motor 551, a spline shaft 552, a spline sleeve 553, and a ratchet mechanism 554. The drive motor 551 is fixedly installed in the assembly column 51 and maintains a power connection with the spline shaft 552. The spline shaft 552 is provided with two groups arranged along the axial direction of the assembly shaft. The spline sleeve 553 is slidably inserted into the spline shaft 552. The spline sleeve 553 is power-connected with two groups of ratchet mechanisms 554 arranged in the same direction. The assembly disk 531 and the rotating seat 533 respectively maintain a power connection with the two groups of ratchet mechanisms 554.

[0119] A drive seat 5511 is also rotatably installed in the assembly column 51. The drive seat 5511 is arranged on the periphery of the drive shaft 541, and the two maintain a concentric layout. The output shaft of the drive motor 551 is connected to the drive seat 5511 through a combination of bevel gears, and the drive seat 5511 is also connected to the two sets of spline shafts 552 through a combination of bevel gears. This design can avoid spatial motion interference between the retractable component 54 and the adjustment component 55.

[0120] The spline shaft 552 and the spline sleeve 553 are designed in a sliding plug-in manner, and during the retraction and extension process of the telescopic sleeve 52, the power of the spline shaft 552 can always be stably transmitted to the spline sleeve 553.

[0121] The ratchet mechanism 554 includes a transmission seat 5541 rotatably installed inside the telescopic sleeve 52, a transmission shaft 5542, and a pawl 5543 assembled on the periphery of the transmission shaft 5542. The transmission seat 5541 and the transmission shaft 5542 are arranged concentrically, and an inner ratchet 5544 engaged with the pawl 5543 is provided on the inner side of the transmission seat 5541. A spring is also arranged between the pawl 5543 and the transmission shaft 5542 to drive the pawl 5543 to spread outward and engage with the inner ratchet 5544.

[0122] The spline sleeve 553 is connected to the two sets of transmission shafts 5542 through a combination of bevel gears, and the two sets of transmission seats 5541 are connected to the rotating seat 533 and the assembly disk 531 through a combination of bevel gears.

[0123] Since the two groups of ratchets are arranged in opposite directions, when the driving motor 551 outputs a forward or reverse rotation speed, it can only drive the transmission seat 5541 in one group of ratchet mechanisms 554 to operate through the combination of the spline shaft 552 and the spline sleeve 553, and then drive the correspondingly connected assembly disk 531 or rotating seat 533 to operate, thereby achieving the adjustment of the vibration force size or direction of the vibration component 53.

[0124] The connecting wires and control lines of the driving motor 551 pass through the outside of the existing tunnel simulation structure 3 and are finally placed outside the model box 1, so that the test personnel can adjust the operating state of the vibration simulation device conveniently.

[0125] Example 5

[0126] See also Figure 10-12 In order to ensure that the data monitoring and acquisition equipment can be installed with the station simulation structure 2, the existing tunnel simulation structure 3 and the filled test soil, and effectively monitor the displacement, stress and strain data during the excavation test, the following technical solutions are provided.

[0127] The data monitoring and acquisition equipment includes a telescopic displacement meter 41, a dial indicator 42, a strain gauge 43, and an earth pressure box 44. The telescopic displacement meter 41 is arranged above the arch structure 21 and above the existing tunnel simulation structure 3. The telescopic displacement meter 41 maintains contact with the arch structure 21 or the existing tunnel simulation structure 3. The dial indicator 42 is arranged on the surface of the experimental soil. The strain gauge 43 is pasted to the top of the arch structure 21 and the bottom of the existing tunnel simulation structure 3. The earth pressure box 44 is arranged at the upper center of the arch structure 21, the arch foot position of the arch structure 21, and the bottom of the existing tunnel simulation structure 3. The earth pressure box 44 maintains contact with the arch structure 21 or the existing tunnel simulation structure 3.

[0128] The above monitoring equipment is arranged inside the main body of the model box 1, fixed by the top steel beam 123, and the wiring terminals are extended to the outside of the box.

[0129] The data monitoring and acquisition equipment also includes a displacement data acquisition device, a stress-strain data acquisition device, and a data processing system. The displacement data acquisition and processing device, the stress-strain data acquisition device, and the data processing system are all located outside the model box 1. The telescopic displacement meter 41 and the dial gauge 42 are connected to the displacement data acquisition device through a data line, and the strain gauge 43 and the earth pressure box 44 are connected to the stress-strain data acquisition device through a data line. The data processing system is loaded into the computer and receives the data from the displacement data acquisition device and the stress data acquisition device for analysis and processing to construct the displacement-excavation stage curve comparison, earth pressure-excavation stage curve comparison, and strain-excavation process stage curve of the corresponding excavation stage.

[0130] By analyzing the data curves, the settlement law of the arch structure 21 of the dark-cut subway station under the influence of the existing tunnel, the stress-strain law of the surrounding rock and the change law of the upper load are obtained, and guidance is provided for the design and construction plan of the subway station excavated under the influence of the existing tunnel in actual engineering.

[0131] Example 6

[0132] According to the above-mentioned test device for simulating the excavation of a subway station under the influence of an existing tunnel, an excavation method is provided, which has the following steps:

[0133] S1, simulated formation configuration:

[0134] According to the size conditions of the model box 1, the geometric similarity ratio between the model size and the on-site prototype size is determined to be 1:L. The model size is designed as 1 / L of the prototype size, and the test soil filled in the model box 1 is designed according to the geometric similarity ratio. The parameters of the test soil comply with the following requirements:

[0135] Geometric similarity ratio: CL = 1;

[0136] Similarity ratios of gravity, internal friction angle and Poisson's ratio: C? = C? = Cμ = 1;

[0137] Similarity ratio of elastic modulus and cohesion: CE = Cc = 1 / L;

[0138] Permeability coefficient similarity ratio: CK = 1 / √L;

[0139] According to laboratory conditions, the geometric similarity ratio between the model size and the prototype size is determined to be 1:L. Based on the geometric similarity ratio L, the size of the loaded ground stress, the diameter of the existing tunnel, the length of the existing tunnel, the design width of the subway station, the design height of the subway station, etc. are designed at 1 / L of the prototype size.

[0140] The test soil parameters should also be designed based on the geometric similarity ratio L, and the specific gravity, internal friction angle and Poisson's ratio of the test soil should be as close as possible to those of the prototype soil. The elastic modulus and cohesion of the test soil should be designed as 1 / L of the prototype soil, and the permeability coefficient of the test soil should be designed as 1 / √L of the prototype soil.

[0141] S2: Model structure, arrangement of data monitoring and acquisition equipment and filling of model box 1:

[0142] According to the positional relationship of the station simulation structure 2, the existing tunnel simulation structure 3, and the data monitoring and acquisition equipment in the model box 1, they are arranged from bottom to top, and the test soil is filled in the gaps;

[0143] After the preparation of the simulated stratum is completed, the test soil filler is made using the relevant proportions to fill the model box 1, and the station simulation structure 2 is arranged according to the set position on the simulated stratum buried at a certain height.

[0144] First, the vertical pile structure 22 and the lining structure 23 are arranged, and the bottom of the vertical pile structure 22 and the lining structure 23 are fixed by concrete materials. The vertical pile structure 22 is used to simulate the vertical support column for the vault and upper load after the excavation of the subway station. The lining structure 23 is composed of wooden boards and is used to simulate the lining protection on both sides during the excavation of the subway station. After the two are fixed, continue to fill the simulated test soil.

[0145] After the vertical pile structure 22 and the lining structure 23 are buried separately, the vault structure 21 and the inner support structure 211 are arranged according to the set positions, and concrete material is applied to the bottom of the two. The vault structure 21 and the support structure 211 are fixed on the simulated stratum on the top of the vertical pile structure 22 and the lining structure 23. The vault structure 21 is formed by overlapping stainless steel plates into an arch shape and filled with gypsum, which is used to simulate the vault support protection structure part during the excavation of the subway station. The support structure 211 is arranged below the vault structure 21 and is composed of wooden boards. It is used to simulate the preliminary support partition wall below the vault support protection structure part during the excavation of the subway station.

[0146] During the process of arranging the station simulation structure 2 and filling the test soil, the corresponding data monitoring and collection equipment are arranged at the same time. After the station simulation structure 2 and the relevant data monitoring and collection equipment are completed, the test soil is continued to be filled to the height of the existing tunnel simulation structure 3, and the existing tunnel simulation structure 3 is arranged to simulate the existing tunnel above during the excavation process of the subway station.

[0147] The bottom of the existing tunnel simulation structure 3 is fixed by using concrete material, and the corresponding data detection and acquisition equipment is fixed at its corresponding position, and the test soil near the existing tunnel simulation structure 3 is filled, and the dial indicator 42 is installed and arranged at the set height.

[0148] The lines of all data monitoring and acquisition equipment in the device are connected to the corresponding data acquisition device from the top of the model box 1, and fixed on the top steel beam 123, and further connected to the computer to monitor the pressure, stress strain and displacement changes before, during and after the excavation of the station in real time.

[0149] After the test device is installed and arranged, it is left to stand for a period of time, and the next step is carried out after the strength of the simulated stratum material in the model box 1 reaches the design data.

[0150] By utilizing the operating opening 1311 on the retaining structure on the front side of the model box 1, the simulated subway station is excavated and supported using the concealed excavation and arch covering method to better simulate the actual working conditions on site. At the same time, relevant data acquisition and processing devices will work synchronously to monitor the pressure, stress strain and displacement changes of relevant structures before, during and after the excavation of the station.

[0151] Before the simulated excavation operation, the supporting baffles on the front retaining structure are removed, and the station simulation structure 2 is excavated using the dark excavation and arch cover method.

[0152] S3, excavation process simulation:

[0153] The operation opening 1311 on the model box 1 is operated to simulate excavation of the test soil in the station simulation structure 2;

[0154] S3-1, first working cycle:

[0155] The left side of the middle guide tunnel 212 is excavated and excavated in four horizontal excavation stages. After each stage is completed, the left arch cover part of the middle guide tunnel 212 is lined with concrete for secondary lining. After the concrete lining strength meets the requirements, the next stage of excavation is carried out;

[0156] S3-2, the second working cycle:

[0157] The right side of the middle guide tunnel 212 is excavated and excavated in four horizontal excavation stages. After each stage is completed, the arch cover part on the right side of the middle guide tunnel 212 is lined with concrete for secondary lining. After the concrete lining strength meets the requirements, the next stage of excavation is carried out;

[0158] S3-3, the third working cycle:

[0159] The left side guide tunnel 213 is excavated and advanced in four horizontal excavation stages. After each stage is completed, the arch cover part of the left side guide tunnel 213 is lined with concrete for secondary lining. After the concrete lining strength meets the requirements, the next stage of excavation is carried out.

[0160] S3-4, the fourth working cycle:

[0161] The right side guide tunnel 214 is excavated and advanced in four horizontal excavation stages. After each stage is completed, the arch cover part of the right side guide tunnel 214 is lined with concrete for secondary lining. After the concrete lining strength meets the requirements, the next stage of excavation is carried out.

[0162] S3-5, Removal of Support Structure 211:

[0163] After the middle guide hole 212, the left side guide hole 213, and the right side guide hole 214 are completely penetrated, the support structure 211 is dismantled, and the top of the vertical pile structure 22 is connected with the arch part by concrete, so as to replace the role of the support structure 211 and serve as a vertical support column to bear the arch structure 21 and the upper load;

[0164] S3-6, station space simulation excavation:

[0165] After the excavation and lining of the vault structure 21 are completed and the overall structure is stable, the station space is simulated excavated according to the step method in the subway excavation method, which is divided into two left and right excavation cycles. Each excavation cycle is divided into four excavation advancement stages in the horizontal direction. After each excavation is completed, the lining structure 23 is relined with concrete;

[0166] S3-7, data analysis and processing:

[0167] In each stage of steps S3-1 to S3-6, the data monitoring and acquisition equipment processes the monitoring data in real time and draws the displacement-excavation stage curve comparison, the earth pressure-excavation stage curve comparison and the strain-excavation process stage curve of the corresponding excavation stage;

[0168] By analyzing the data curves, the settlement law of the arch structure 21 of the dark-cut subway station under the influence of the existing tunnel, the stress-strain law of the surrounding rock and the change law of the upper load are obtained, and guidance is provided for the design and construction plan of the subway station excavated under the influence of the existing tunnel in actual engineering.

[0169] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0170] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A test device for simulating the excavation of a subway station under the influence of an existing tunnel, characterized in that: It comprises a model box (1), a station simulation structure (2) arranged in the model box (1), an existing tunnel simulation structure (3), and data monitoring and collection equipment; The existing tunnel simulation structure (3) is arranged above the station simulation structure (2), and the model box (1) and the internal space of the station simulation structure (2) are filled with test soil; The data monitoring and collection equipment is installed at the station simulation structure (2), the existing tunnel simulation structure (3) and the surface of the test soil.

2. The test device for simulating the excavation of a subway station under the influence of an existing tunnel according to claim 1, characterized in that: The model box (1) comprises a bottom support (11), a support frame (12), and a retaining structure; the support frame (12) is fixedly connected to the bottom support (11); the support frame (12) is formed by splicing and fixing vertical steel beams (121), transverse steel beams (122), and top steel beams (123); and the retaining structure is arranged on the periphery of the support frame (12).

3. The test device for simulating the excavation of a subway station under the influence of an existing tunnel according to claim 2, characterized in that: The support structure comprises a front baffle (131), a back baffle (132), and a side baffle (133); the front baffle (131) and the back baffle (132) are respectively fixedly connected to the front and back of the support frame (12); and the side baffle (133) is fixedly connected to two side surfaces of the support frame (12); The front baffle (131) and the back baffle (132) are made of organic glass plates. An operation opening (1311) is provided on the front baffle (131), and a supporting baffle is installed outside the operation opening (1311).

4. The test device for simulating the excavation of a subway station under the influence of an existing tunnel according to claim 3, characterized in that: The station simulation structure (2) comprises an arch structure (21), a vertical pile structure (22), and a lining structure (23); the inner side of the arch structure (21) is equipped with two groups of supporting structures (211) arranged side by side; the supporting structure (211) divides the internal space of the arch structure (21) into a central guide tunnel (212) and a left side guide tunnel (213) and a right side guide tunnel (214) on both sides of the central guide tunnel (212); the lining structure (23) comprises a bottom lining and side linings connected to both sides of the bottom lining and arranged in a vertical direction, the top of the side lining being connected to the bottom of the arch structure (21); the vertical pile structure (22) is supported on the bottom lining and is kept in contact with the supporting structure (211).

5. The test device for simulating the excavation of a subway station under the influence of an existing tunnel according to claim 4, characterized in that: The existing tunnel simulation structure (3) comprises a pipeline structure (31), a port baffle (32), and a connecting gasket (33); the pipeline structure (31) comprises a plurality of sections butted end to end; two sections of the pipeline structure (31) are fixedly connected by a connecting gasket (33) and bolts penetrating the connecting gasket (33) and screwed to the pipeline structure (31); and the port position of the pipeline structure (31) at the outermost side is blocked by a port baffle (32).

6. The test device for simulating the excavation of a subway station under the influence of an existing tunnel according to claim 5, characterized in that: The existing tunnel simulation structure (3) can be equipped with a vibration simulation device, which comprises an assembly column (51), a telescopic sleeve (52), a vibration assembly (53), a retractable assembly (54), and an adjustment assembly (55). The assembly column (51) is assembled in the pipeline structure (31), the telescopic sleeve (52) is slidably inserted at both ends of the assembly column (51), the vibration assembly (53) is rotatably installed in the telescopic sleeve (52), the retractable assembly (54) is assembled in the assembly column (51) and keeps linkage with the two sets of telescopic sleeves (52), and the adjustment assembly (55) keeps linkage with the vibration assembly.

7. The test device for simulating the excavation of a subway station under the influence of an existing tunnel according to claim 6, characterized in that: The retractable assembly (54) comprises a drive shaft (541) and an adjusting screw (542). The drive shaft (541) is rotatably mounted in the assembly column (51) and arranged in the radial direction. An operating knob (5411) is fixedly connected to the end of the drive shaft (541). The operating knob (5411) is arranged on the outside of the assembly column (51). The adjusting screw (542) is rotatably mounted in the assembly column (51) and arranged in the axial direction. The inner end of the telescopic sleeve (52) is rotationally connected to the adjusting screw (542). A driving bevel gear (5412) is fixedly connected to the drive shaft (541). The inner end of the adjusting screw (542) is fixedly connected to a transmission bevel gear (5421) meshing with the driving bevel gear (5412).

8. The test device for simulating the excavation of a subway station under the influence of an existing tunnel according to claim 7, characterized in that: The vibration assembly (53) comprises an assembly disk (531), a counterweight slide seat (532), a rotating seat (533), and a connecting rod (534); the assembly disk (531) is rotatably mounted in the telescopic sleeve (52); a radially arranged guide groove (5311) is provided on the assembly disk (531); the counterweight slide seat (532) is slidably mounted in the guide groove (5311); a clearance through hole (5321) is provided on the counterweight slide seat (532); the rotating seat (533) is rotatably mounted at the axis of the assembly disk (531) and arranged in the clearance through hole (5321); two ends of the connecting rod (534) are respectively hinged to the outer edge of the rotating seat (533) and the counterweight slide seat (532); and the adjustment assembly (55) is linked to the assembly disk (531) and the rotating seat (533); The adjustment assembly (55) comprises a driving motor (551), a spline shaft (552), a spline sleeve (553), and a ratchet mechanism (554); the driving motor (551) is fixedly installed in the assembly column (51) and maintains a power connection with the spline shaft (552); the spline shaft (552) is provided with two groups arranged along the axis direction of the assembly shaft; the spline sleeve (553) is slidably plugged onto the spline shaft (552); the spline sleeve (553) is power-connected with two groups of ratchet mechanisms (554) arranged in the same direction; the assembly disk (531) and the rotating seat (533) respectively maintain a power connection with the two groups of ratchet mechanisms (554).

9. The test device for simulating the excavation of a subway station under the influence of an existing tunnel according to claim 8, characterized in that: The data monitoring and acquisition equipment comprises a telescopic displacement meter (41), a dial indicator (42), a strain gauge (43), and an earth pressure box (44); the telescopic displacement meter (41) is arranged above the arch structure (21) and above the existing tunnel simulation structure (3); the telescopic displacement meter (41) is in contact with the arch structure (21) or the existing tunnel simulation structure (3); the dial indicator (42) is arranged on the surface of the test soil; the strain gauge (43) is attached to the top of the arch structure (21) and the bottom of the existing tunnel simulation structure (3); the earth pressure box (44) is arranged at the center of the top of the arch structure (21), at the arch foot of the arch structure (21), and below the existing tunnel simulation structure (3); the earth pressure box (44) is in contact with the arch structure (21) or the existing tunnel simulation structure (3).

10. The test device for simulating the excavation of a subway station under the influence of an existing tunnel according to claim 9 provides an excavation method, characterized in that: The steps are as follows: S1, simulated formation configuration: According to the size conditions of the model box (1), the geometric similarity ratio between the model size and the on-site prototype size is determined to be 1:L, the model size is designed according to 1 / L of the prototype size, and the test soil filled in the model box (1) is designed according to the geometric similarity ratio. The parameters of the test soil comply with the following requirements: Geometric similarity ratio: CL = 1; Similarity ratios of gravity, internal friction angle and Poisson's ratio: C? = C? = Cμ = 1; Similarity ratio of elastic modulus and cohesion: CE = Cc = 1 / L; Permeability coefficient similarity ratio: CK = 1 / √L; S2: Model structure, arrangement of data monitoring and acquisition equipment and filling of model box (1): Arrange the station simulation structure (2), the existing tunnel simulation structure (3), and the data monitoring and acquisition equipment from bottom to top in the model box (1) according to their positional relationship, and fill the gaps with test soil; S3, excavation process simulation: Operating the operating opening (1311) on the model box (1) to simulate excavation of the test soil in the station simulation structure (2); S3-1, first working cycle: The left side of the middle guide tunnel (212) is excavated and advanced in four horizontal excavation stages. After each stage is completed, the left arch cover part of the middle guide tunnel (212) is lined with concrete for secondary lining. After the concrete lining strength meets the requirements, the next stage of excavation is carried out. S3-2, the second working cycle: The right side of the middle guide tunnel (212) is excavated and advanced in four horizontal excavation stages. After each stage is completed, the right side arch cover part of the middle guide tunnel (212) is lined with concrete for secondary lining. After the concrete lining strength meets the requirements, the next stage of excavation is carried out. S3-3, the third working cycle: The left side guide tunnel (213) is excavated and advanced in four horizontal excavation stages. After each stage is completed, the arch cover part of the left side guide tunnel (213) is lined with concrete for a secondary lining. After the concrete lining strength meets the requirements, the next stage of excavation is carried out. S3-4, the fourth working cycle: The right side guide tunnel (214) is excavated and advanced in four horizontal excavation stages. After each stage is completed, the arch cover part of the right side guide tunnel (214) is lined with concrete for a secondary lining. After the concrete lining strength meets the requirements, the next stage of excavation is carried out. S3-5, Removal of supporting structure (211): After the middle guide hole (212), the left side guide hole (213), and the right side guide hole (214) are completely penetrated, the support structure (211) is dismantled, and the pile top of the vertical pile structure (22) is connected to the arch part by concrete, so as to replace the function of the support structure (211) and serve as a vertical support column to bear the arch structure (21) and the upper load; S3-6, station space simulation excavation: After the excavation and lining of the vault structure (21) is completed and the overall structure is stable, the station space is simulated excavated according to the step method in the subway excavation method, which is divided into two left and right excavation cycles. Each excavation cycle is divided into four excavation advancement stages in the horizontal direction. After each excavation is completed, the lining structure (23) is relined with concrete; S3-7, data analysis and processing: In each stage of steps S3-1 to S3-6, the data monitoring and acquisition equipment processes the monitoring data in real time and draws the displacement-excavation stage curve comparison, the earth pressure-excavation stage curve comparison and the strain-excavation process stage curve of the corresponding excavation stage; By analyzing the data curves, the settlement law of the arch structure (21) of the underground subway station under the influence of the existing tunnel, the stress-strain law of the surrounding rock and the change law of the upper load are obtained, and guidance is provided for the design and construction plan of the subway station excavated under the influence of the existing tunnel in actual engineering.

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