A simulation test device and method for simulating a subway station with concealed excavation

Abstract

The application discloses a simulation test device and method for simulating a subway station with underground excavation, wherein a model box, a station arch cover model, a station main body model and a monitoring device are arranged in the simulation test device; the station arch cover model and the station main body model are arranged in the model box, and the station arch cover model is arranged above the station main body model; the station arch cover model and the station main body model are placed in the model box by filling soil; and the monitoring device monitors the settlement and stress change of the arch cover part in the excavation process. In the simulation test method, the model box is simulated to be excavated, including the excavation and lining work of the station arch cover model and the station main body model, and various data are monitored by the monitoring device to create relevant curves of the data-excavation stage and analyze and study the stress and strain and displacement law of the station arch cover part of the subway station with underground excavation under complex environment.

Description

Technical Field

[0001] This invention relates to the field of subway station construction technology, specifically a simulation test device for simulating the construction of underground subway stations. Background Technology

[0002] In subway station construction, the cut-and-cover method is a common construction technique. This method typically involves large tunnel cross-sections, shallow tunnel depths, significant surface loads, complex surrounding rock geological conditions, high requirements for tunnel settlement, and considerable excavation difficulty. Addressing these characteristics of cut-and-cover construction presents numerous challenges for subway station construction using this method.

[0003] Model tests and methods can effectively simulate the construction process of underground subway stations under complex environments. By comparing experimental and numerical simulation results, further research can be conducted on the construction of underground subway stations. Currently, there is little research on model tests and methods for the construction process of underground subway stations.

[0004] Therefore, for underground engineering projects such as cut-and-cover subway stations, a simulation test device and method for simulating cut-and-cover subway stations are designed, and the relevant changes in the excavation process are studied. By combining and comparing relevant data from numerical simulation of the excavation process, the stress, strain and displacement laws at the construction site can be analyzed, and further reference can be provided for the optimization of the design and construction scheme of cut-and-cover subway stations. Summary of the Invention

[0005] To address the aforementioned shortcomings in existing technologies, the present invention aims to provide a simulation test device and method for simulating the excavation process of a tunnel-cut subway station. After the model is designed and manufactured, the excavation process is simulated to analyze and study the stress, strain, and displacement characteristics of the tunnel-cut subway station's underpass under complex environments.

[0006] The technical solution adopted by the present invention to achieve the above-mentioned objectives is as follows: a simulation test device for simulating a tunneled subway station, comprising a model box, a station arch model, a station main body model, and a monitoring device. The front side wall of the model box has an operating opening, and multiple sets of forward baffles arranged side by side are spliced ​​at the operating opening. The station arch model and the station main body model are both arranged in the model box. The station main body model includes a load-bearing base plate and load-bearing columns. The load-bearing base plate is arranged horizontally in the model box, and the load-bearing columns are fixedly installed on the load-bearing base plate and kept vertical. The station arch model is arranged on top of the load-bearing columns. The monitoring device includes a telescopic displacement gauge, a strain gauge, and an earth pressure cell. The telescopic displacement gauge, strain gauge, and earth pressure cell are arranged above the station arch model and buried in the backfill inside the model box.

[0007] In some implementations, the following technical solutions are provided to facilitate the construction of the model box, the filling of soil into the model box, and the removal of each component and the soil from the model box after the test.

[0008] The model box includes a base plate support, horizontal support members, vertical support members, side baffles, and back baffles. The vertical support members include multiple sets arranged vertically above the base plate support, and each set of vertical support members is fixedly installed on the left and right sides of the base plate support. The horizontal support members include multiple sets arranged horizontally above the base plate support, and each set of horizontal support members is fixedly connected to the vertical support members and arranged on the left and right sides and back of the model box. The side baffles are arranged on the left and right sides of the model box and fixedly connected to the corresponding horizontal and vertical support members. The back baffles are arranged on the back of the model box and fixedly connected to the corresponding horizontal support members.

[0009] In some implementations, the following technical solutions are provided to facilitate the installation of the detection device at a specific location within the model housing.

[0010] The model box also includes multiple hanging beams arranged side by side, which are located at the top of the model box and fixedly connected to the horizontal support.

[0011] In some of these implementations, to ensure that the main structure of the station can accurately simulate the stress conditions of the main structure of the subway station, and to effectively support the arch and disperse stress, the following technical solutions for the main structure of the station are provided.

[0012] The main model of the station also includes a connecting base and a positioning plate. The connecting base is nested and fixed on the load-bearing base plate. The load-bearing column is fixedly connected to the top surface of the connecting base. The positioning plate has multiple sets of positioning holes that nest and match the outer wall of the load-bearing column. The positioning plate and each set of the load-bearing column are nested and inserted into each other.

[0013] In some implementations, the following technical solutions are provided to ensure that the connecting base can be stably installed on the connecting base.

[0014] The upper surface of the load-bearing base plate is fixed with multiple sets of positioning blocks, and the lower surface of the connecting base is provided with positioning grooves that nest and match the positioning blocks. The load-bearing base plate and the connecting base are combined by nesting positioning blocks and positioning grooves.

[0015] In some of these implementations, to ensure that the station arch model can perfectly simulate the arch structure of the subway station, the following technical solutions for the station arch model are provided.

[0016] The station arch model includes an arch top structure and an initial support structure. The arch top structure includes an arc-shaped structure and an L-shaped structure. The L-shaped structure is fixedly connected to both sides of the arc-shaped structure. The initial support structure includes a central partition wall support and side partition wall supports fixedly installed on the lower surface of the arc-shaped structure. The side partition wall supports are arranged on both sides of the central partition wall support. The space between the central partition wall support and the side partition wall support is set as a central guide hole, and the space between the side partition wall support and the L-shaped structure is set as a side guide hole. The bottom of the L-shaped structure is arranged at the top of the load-bearing column.

[0017] In some implementations, in the simulation test method of simulating the underground subway station, it is necessary to fill the central and side guide tunnels with gypsum. In order to avoid the central partition wall support and side partition wall support welded to the lower part of the arc structure from affecting the integrity of the gypsum filling, the following technical solution is also provided.

[0018] Both the central partition wall support and the side partition wall support are provided with evenly arranged connecting holes.

[0019] In some of these implementations, the following technical solutions are provided to ensure that the data detected by the telescopic displacement gauge, strain gauge, and earth pressure cell can be effectively collected and processed.

[0020] It is also equipped with a data collection and processing device, which includes a displacement data acquisition device, a stress-strain data acquisition and processing device, and a computer. The displacement data acquisition device is connected to the telescopic displacement gauge via a data cable, and the stress-strain data acquisition and processing device is connected to the strain gauge and the earth pressure cell via a data cable. The displacement data acquisition device and the stress-strain data acquisition and processing device are also connected to the computer via signal.

[0021] A simulation test method for a tunnel-cut subway station, characterized by using the aforementioned simulation test device for tunnel-cut subway stations, comprising the following steps:

[0022] S1, Construction of the simulation experimental setup:

[0023] The station main body model and station arch model are installed into the assembled model box. At the same time, the backfilling and monitoring device installation are completed. After the soil strength reaches the design data, the front baffle blocking the station main body model and station arch model is removed.

[0024] S2, First Working Cycle:

[0025] Excavation of the central pilot tunnels on the left and right sides is carried out. The excavation work of the central pilot tunnel on each side includes at least two excavation stages. After each stage is completed, the excavation space of the central pilot tunnel is lined with gypsum for a second time. After the strength of the gypsum lining meets the set requirements, the next stage of excavation work is carried out.

[0026] S3, Second Work Cycle:

[0027] Excavation of the pilot tunnels on the left and right sides is carried out. The development of each pilot tunnel includes at least two excavation stages. After each stage is completed, the excavation space of the pilot tunnel is lined with gypsum. Once the strength of the gypsum lining meets the set requirements, the next stage of excavation work is carried out.

[0028] S4, Excavation of the main structure of the station:

[0029] After the station arch structure was excavated through the first and second work cycles, the step method was used to excavate the fill in the main model of the station from top to bottom. After each excavation was completed, gypsum was used to line the gap between the two load-bearing columns and form the side wall.

[0030] S5, Monitoring Data Processing:

[0031] During steps S2-4, displacement, stress, and strain are monitored using telescopic displacement gauges, strain gauges, and earth pressure cells. Relevant data are collected using displacement data acquisition devices and stress-strain data acquisition devices to plot data change curves based on the excavation stage. Simultaneously, all data are transmitted to a computer in real time for processing and numerical simulation experiments to determine the change status of each data with respect to the tunneling process.

[0032] S6, Summary of Patterns:

[0033] Based on step S5, the settlement, stress-strain variation, and upper earth pressure variation of the excavated station arch section under model box test and numerical simulation test are obtained, providing guidance for the engineering design and construction plan of the actual excavated station.

[0034] The beneficial effects of this invention are as follows: By using the baffles and backfill around the model box to simulate the confining pressure stress generated by the surrounding environment during subway excavation, the actual excavation environment is fully simulated, which is more conducive to the research and analysis of specific processes. Addressing the difficulty in designing simulation tests for underground subway stations, this invention innovatively pre-embeds the station arch simulation device and the main station model, greatly improving the operability of the test and shortening the time for simulating support lining. During data acquisition and processing, the on-site monitoring environment can be effectively simulated, while reducing the workload and operation time of post-processing. By comparing the real-time monitoring data from the experiment with the relevant data from the numerical simulation, optimization and reference are provided for the design and construction schemes of actual subway stations on site. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the structure of the simulation test device in this invention;

[0036] Figure 2 This is a schematic diagram of the model box structure;

[0037] Figure 3 This is a schematic diagram of the structure after combining the station arch model and the main station model;

[0038] Figure 4 This is a schematic diagram of the arch model.

[0039] Figure 5 This is a graph showing the displacement versus excavation stage measured by the model box test in this invention.

[0040] Figure 6 This is a graph showing the displacement versus excavation stage obtained from numerical simulation experiments according to the present invention.

[0041] Figure 7 This is a graph showing the stress versus excavation stage obtained from the model box test of this invention.

[0042] Figure 8 is a graph showing the stress versus excavation stage obtained from numerical simulation experiments according to the present invention.

[0043] In the diagram: 11 Operating opening, 12 Forward baffle, 13 Base plate support, 14 Horizontal support, 15 Vertical support, 16 Side baffle, 17 Back baffle, 18 Hanging beam, 211 Arc structure, 212 L-shaped structure, 221 Central partition wall support, 222 Side partition wall support, 223 Central guide hole, 224 Side guide hole, 225 Connecting hole, 31 Load-bearing base plate, 32 Load-bearing column, 33 Connecting base, 34 Positioning plate. Detailed Implementation

[0044] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0045] Please see Figure 1-8 The present application will be described below in conjunction with the following embodiments. Example

[0046] A simulation test device for a tunnel-excavated subway station includes a model box, a station arch model, a station main body model, and a monitoring device. The front side wall of the model box has an operation opening 11, and multiple sets of forward baffles 12 arranged side by side are spliced ​​at the operation opening 11. The station arch model and the station main body model are both arranged in the model box. The station main body model includes a load-bearing base plate 31 and load-bearing columns 32. The load-bearing base plate 31 is arranged horizontally in the model box, and the load-bearing columns 32 are fixedly installed on the load-bearing base plate 31 and kept vertical. The station arch model is arranged on top of the load-bearing columns 32. The monitoring device includes a telescopic displacement gauge, a strain gauge, and an earth pressure cell. The telescopic displacement gauge, strain gauge, and earth pressure cell are arranged above the station arch model and buried in the backfill inside the model box.

[0047] The constructed simulation test device simulates the construction process of subway station excavation and support. The monitoring device can monitor the soil pressure, stress and strain and displacement changes of the arch top of the station arch model in real time. By comparing the relevant data of the model box and numerical simulation at different excavation stages, the monitoring data obtained from the model box experiment, including the arch top displacement and settlement, the stress and strain of the arch part and the soil pressure, are further verified and the corresponding change laws are obtained. Example

[0048] To facilitate the construction of the model box, the filling of soil into the model box, and the removal of each component and the soil from the model box after the test, the following technical solutions are provided.

[0049] The model box includes a base plate support 13, horizontal support members 14, vertical support members 15, side baffles 16, and back baffles 17. The vertical support members 15 include multiple sets arranged vertically above the base plate support 13, and each set of vertical support members 15 is fixedly installed on the left and right sides of the base plate support 13. The horizontal support members 14 include multiple sets arranged horizontally above the base plate support 13, and each set of horizontal support members 14 is fixedly connected to the vertical support members 15 and arranged on the left and right sides and back of the model box. The side baffles 16 are arranged on the left and right sides of the model box and fixedly connected to the corresponding horizontal support members 14 and vertical support members 15. The back baffles 17 are arranged on the back of the model box and fixedly connected to the corresponding horizontal support members 14.

[0050] In practice, the outer dimensions of the model box are set to 1800*1000*1800mm. Based on this, the dimensions of the vertical support 15 are set to 50*5*1800mm, and there are six sets of vertical support 15, with three sets evenly arranged on each side of the base plate support 13. The cross-sectional dimensions of the horizontal support 14 are set to 50*5mm, and each horizontal support frame is connected between two adjacent sets of vertical support 15. The horizontal support 14 is generally set in three layers at different heights to seal the left and right sides and the back of the model box.

[0051] The base plate support 13, the horizontal support 14, and the vertical support 15 are all made of rigid materials. In this implementation, they are made of iron and are fixed together by welding. An angle steel frame is also welded to the bottom of the base plate support 13 to reinforce the vertical support 15.

[0052] Based on the above structural design, four sets of side baffles 16 are provided with the same size, which is approximately 1800*900*10mm. Two sets of side baffles 16 are arranged closely on both the left and right sides of the model box, and the side baffles 16 are fixed to the corresponding vertical support 15 and horizontal support 14 by bolts. One set of back baffles 17 is provided, which is approximately 1800*1000mm in size, and is fixed to the horizontal support 14 on the back side by bolts.

[0053] Based on the above design, the front side of the model box does not have horizontal support members 14 or vertical support members 15, so as to form an operation port 11. The front baffles 12 matched at the operation port 11 include six sets of horizontally arranged baffles 12 with the same size. The size of each front baffle 12 is approximately 1000*300*10mm. The front baffles 12 and the vertical support members 15 on both sides are also fixed together by bolts.

[0054] The side baffle 16, the back baffle 17, and the front baffle 12 can all be freely disassembled, making it easy to remove the backfill, the station arch model, and the station main body model.

[0055] The back baffle 17 is made of steel plate to ensure its strength, while the side baffle 16 is made of transparent plexiglass, allowing for direct observation of the positional changes of the backfill in the simulation chamber while ensuring its own strength. The front baffle 12 is made of 5mm thick plywood, which can be disassembled and assembled sequentially to facilitate the backfilling and removal of soil during the experiment.

[0056] To facilitate the installation of the testing device at a specific location within the model housing, the following technical solution is also provided.

[0057] The model box also includes multiple hanging beams 18 arranged side by side, which are located on the top of the model box and fixedly connected to the horizontal support member 14.

[0058] Two hanging beams 18 are provided and arranged horizontally. Their dimensions are designed to be 1000*50*5mm. They are erected along the width direction of the model box, and the hanging beams 18 are fixedly connected to the corresponding horizontal support members 14 on the top layer by welding.

[0059] The design of the hanging beam 18 can effectively fix the telescopic displacement gauge, ensuring that it can monitor the amount of soil displacement. Example

[0060] To ensure that the main structure of the station can accurately simulate the stress conditions of the main structure of the subway station, and to effectively support the arch and disperse stress, the following technical solutions for the main structure of the station are provided.

[0061] The main model of the station also includes a connecting base 33 and a positioning plate 34. The connecting base 33 is nested and fixed on the load-bearing base plate 31. The load-bearing column 32 is fixedly connected to the top surface of the connecting base 33. The positioning plate 34 has multiple sets of positioning holes that fit into the outer wall of the load-bearing column 32. The positioning plate 34 and each set of load-bearing columns 32 are nested and inserted into each other.

[0062] The load-bearing base plate 31 is supported by a 5mm thick wooden board and placed on a soil layer filled to a specific depth, which can transfer the load borne by the upper structure to the soil layer below.

[0063] As a preferred embodiment, the connecting base 33 has four sets, which are cast from frustum-shaped concrete with a height of 30mm, a bottom diameter of 65mm, and an upper diameter of 55mm. Its function is to fix the load-bearing column 32 and at the same time transfer the force of the upper structure to the bottom plate and soil layer below.

[0064] The load-bearing column 32 is supported by a steel pipe with a wall thickness of 5mm, an outer diameter of 50mm, and a height of 750mm. The inside of the steel pipe is filled with concrete. The load-bearing column 32 consists of four sets, which are connected to four sets of connecting seats and are arranged vertically. The load-bearing column 32 is used to bear the force of the main station model and is a major component.

[0065] The load-bearing column 32 and the connecting base 33 are cast into a unified whole by concrete casting to ensure the strength of the connection between the two and facilitate their installation onto the load-bearing base plate 31. After the load-bearing column 32 and the connecting base 33 are installed on the load-bearing base plate 31, a certain depth of soil is filled into the model box. Then, the positioning plate 34 is nested and inserted into each group of load-bearing columns 32 to accurately position each load-bearing column 32, avoiding uneven filling that could cause individual load-bearing columns 32 to tilt, thus ensuring the accuracy of the simulation test.

[0066] The positioning plate 34 is made of a 5mm thick wooden board, with a 60mm diameter circular positioning hole cut out at the corresponding position so that the positioning hole can be stably inserted into the steel pipe on the outside of the load-bearing column 32.

[0067] Then, soil was filled into the model box until it reached a certain height, and then the station arch model was installed on top of each load-bearing column 32.

[0068] To ensure that the connecting base 33 can be stably installed on the connecting base 33, the following technical solution is also provided.

[0069] Multiple sets of positioning blocks are fixed on the upper surface of the load-bearing base plate 31, and a positioning groove that nests and matches the positioning blocks is opened on the lower surface of the connecting base 33. The load-bearing base plate 31 and the connecting base 33 are combined by the nesting of positioning blocks and positioning grooves.

[0070] A positioning block is fixed at the corresponding position on the load-bearing base plate 31 by air nails. The positioning block is also made of wood. When casting the connecting base 33, a positioning groove is pre-set. The connecting base 33 is fixed on the load-bearing base plate 31 by the combination of the positioning block and the positioning groove. Example

[0071] To ensure that the station arch model can perfectly simulate the arch structure of the subway station, the following technical solutions for the station arch model are provided.

[0072] The station arch model includes an arch structure and a primary support structure. The arch structure includes an arc-shaped structure 211 and an L-shaped structure 212. The L-shaped structure 212 is fixedly connected to both sides of the arc-shaped structure 211. The primary support structure includes a central partition wall support 221 and a side partition wall support fixedly installed on the lower surface of the arc-shaped structure 211. The side partition wall support is arranged on both sides of the central partition wall support 221. The space between the central partition wall support 221 and the side partition wall support is set as a central guide hole 223, and the space between the side partition wall support and the L-shaped structure 212 is set as a side guide hole 224. The bottom of the L-shaped structure 212 is arranged on the top of the load-bearing column 32.

[0073] The arched component is made of three iron plates that are fixedly connected. One plate is bent into an arc-shaped structure 211, and the other two plates are bent into L-shaped structures 212 and connected to both sides of the arc-shaped structure 211 respectively. The arc-shaped structure 211 and the L-shaped structure 212 are fixedly combined by bolts or welding.

[0074] Both the central partition wall support 221 and the side partition wall support are made of iron plates and are welded to the lower surface of the arc-shaped structure 211 by welding. The side partition wall support is arranged on both sides of the central partition wall support 221.

[0075] In the simulation test method for a subway station with a cut-and-cover tunnel, plaster needs to be filled into each central guide tunnel 223 and side guide tunnel 224. To avoid the central partition wall support 221 and side partition wall support welded below the arc structure 211 from affecting the integrity of the plaster filling, the following technical solution is also provided.

[0076] Both the central partition wall support 221 and the side partition wall support are provided with evenly arranged connecting holes 225.

[0077] The connection hole 225 ensures that the plaster in each independent space is bonded into a unified whole, so as to simulate the construction process of the arch of a subway station and improve the integrity of the arch structure. Example

[0078] To ensure the effective collection and processing of data detected by telescopic displacement gauges, strain gauges, and earth pressure cells, the following technical solutions are also provided.

[0079] It is also equipped with a data collection and processing device, which includes a displacement data acquisition device, a stress-strain data acquisition and processing device, and a computer. The displacement data acquisition device is connected to the telescopic displacement gauge via a data cable, and the stress-strain data acquisition and processing device is connected to the strain gauge and earth pressure cell via a data cable. The displacement data acquisition device and the stress-strain data acquisition and processing device are also connected to the computer signal.

[0080] Multiple sets of telescopic displacement gauges, strain gauges, and earth pressure cells are installed. When filling the model box with soil to the station arch model, each set of telescopic displacement gauges, strain gauges, and earth pressure cells is placed at the predetermined position above the arc structure 211. Then, the filling continues until completion. The displacement data acquisition device and stress-strain data acquisition and processing device collect the data, which can monitor the pressure, stress-strain, and displacement changes before and after the station is excavated and during the excavation process in real time. Example

[0081] A simulation test method for a tunnel-cut subway station, using the aforementioned simulation test device for tunnel-cut subway stations, includes the following steps:

[0082] S1, Construction of the simulation experimental setup:

[0083] The station main body model and station arch model are installed into the assembled model box. At the same time, the backfilling and monitoring device installation are completed. After the soil strength reaches the design data, the front baffle 12 blocking the station main body model and station arch model is removed.

[0084] S2, First Working Cycle:

[0085] Excavation of the central tunnels 223 on the left and right sides is carried out. The excavation work of the central tunnels 223 on each side includes at least two excavation stages. After each stage is completed, the excavation space of the central tunnel 223 is lined with plaster. After the plaster lining strength meets the set requirements, the next stage of excavation work is carried out.

[0086] S3, Second Work Cycle:

[0087] Excavation and excavation of the left and right side guide tunnels 224 are carried out. The development work of each side guide tunnel 224 includes at least two excavation stages. After each stage is completed, the excavation space of the side guide tunnel 224 is lined with plaster. After the strength of the plaster lining meets the set requirements, the next stage of excavation work is carried out.

[0088] S4, Excavation of the main structure of the station:

[0089] After the station arch structure was excavated through the first and second work cycles, the step method was used to excavate the fill in the main model of the station from top to bottom. After each excavation was completed, gypsum was used to line the gap between the two load-bearing columns 32 and form the side wall.

[0090] S5, Monitoring Data Processing:

[0091] During steps S2-4, displacement, stress, and strain are monitored using telescopic displacement gauges, strain gauges, and earth pressure cells. Relevant data are collected using displacement data acquisition devices and stress-strain data acquisition devices to plot data change curves based on the excavation stage. Simultaneously, all data are transmitted to a computer in real time for processing and numerical simulation experiments to determine the change status of each data with respect to the tunneling process.

[0092] S6, Summary of Patterns:

[0093] Based on step S5, the settlement law, stress-strain variation law, and upper earth pressure variation law of the excavated station arch section under model box test and numerical simulation test are obtained, which provides guidance for the engineering design and construction plan of the actual excavated station.

[0094] In the first working cycle, the excavation work of the central guide tunnel 223 on the left and right sides can be carried out simultaneously or sequentially. Similarly, the excavation work of the side guide tunnels 224 on the left and right sides can be carried out simultaneously or sequentially.

[0095] In the first and second working cycles, the tunneling stage refers to segmented tunneling along the length of the station arch model. This approach can reduce the amount of excavated soil in each excavation process. Using a small amount of soil in multiple excavations can avoid large fluctuations in various monitoring data, thereby effectively improving the overall stability of the structure.

[0096] During the excavation of the main structure of the station, the step-by-step excavation method from top to bottom can reduce the amount of soil excavated in each excavation process. The method of excavating in small amounts and multiple times can avoid large fluctuations in various monitoring data, thereby effectively improving the overall stability of the structure.

[0097] In the monitoring data processing, the monitoring data is transmitted to the computer in real time for processing and plotting the displacement-excavation stage curve comparison, earth pressure-excavation stage curve comparison, and strain-excavation process stage curve corresponding to the excavation stage.

[0098] Using FLAC 3D The software establishes a numerical model of the model box, calculates the monitoring data of the numerical model, and compiles the curves corresponding to the excavation stages during the excavation process of the model box. By comparing the data curves obtained by the model test method and the curves obtained by the numerical model calculation, the trends and correlations between the two are compared. This allows for the determination of the settlement law, stress-strain variation law, and upper earth pressure variation law of the arch section of the underground subway station under the model box test and numerical simulation test. The software also provides guidance for the engineering design and construction scheme of underground subway stations, deriving the settlement law, surrounding rock stress-strain law, and upper load variation law of the arch section.

[0099] It will be apparent to those skilled in the art that the present 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 its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0100] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A simulation test device for simulating the construction of a subway station using a cut-and-cover method, characterized in that: The system includes a model box, a station arch model, a station main model, and a monitoring device. The front side wall of the model box has an operation opening (11), and multiple sets of forward baffles (12) arranged side by side are spliced ​​at the operation opening (11). The station arch model and the station main model are both arranged in the model box. The station main model includes a load-bearing base plate (31) and a load-bearing column (32). The load-bearing base plate (31) is arranged horizontally in the model box. The load-bearing column (32) is fixedly installed on the load-bearing base plate (31) and kept vertical. The station arch model is arranged on top of the load-bearing column (32). The monitoring device includes a telescopic displacement gauge, a strain gauge, and an earth pressure cell. The telescopic displacement gauge, strain gauge, and earth pressure cell are arranged above the station arch model and buried in the backfill inside the model box.

2. The simulation test device for simulating the underground construction of a subway station according to claim 1, characterized in that: The model box includes a base plate support (13), a horizontal support (14), a vertical support (15), a side baffle (16), and a back baffle (17). The vertical support (15) includes multiple sets arranged vertically above the base plate support (13). Each set of vertical support (15) is fixedly installed on the left and right sides of the base plate support (13). The horizontal support (14) includes multiple sets arranged horizontally above the base plate support (13). Each set of horizontal support (14) is fixedly connected to the vertical support (15) and arranged on the left and right sides and the back side of the model box. The side baffle (16) is arranged on the left and right sides of the model box and fixedly connected to the corresponding horizontal support (14) and vertical support (15). The back baffle (17) is arranged on the back side of the model box and fixedly connected to the corresponding horizontal support (14).

3. The simulation test device for simulating the underground subway station as described in claim 2, characterized in that: The model box also includes multiple hanging beams (18) arranged side by side. The hanging beams (18) are arranged on the top of the model box and fixedly connected to the horizontal support (14).

4. The simulation test device for simulating the underground construction of a subway station according to claim 3, characterized in that: The main model of the station also includes a connecting base (33) and a positioning plate (34). The connecting base (33) is nested and fixed on the load-bearing base plate (31). The load-bearing column (32) is fixedly connected to the top surface of the connecting base (33). The positioning plate (34) has multiple sets of positioning holes that fit into the outer wall of the load-bearing column (32). The positioning plate (34) and each set of the load-bearing column (32) are nested and inserted.

5. The simulation test device for simulating the underground subway station as described in claim 4, characterized in that: The upper surface of the load-bearing base plate (31) is fixed with multiple sets of positioning blocks, and the lower surface of the connecting base (33) is provided with a positioning groove that nests and matches the positioning blocks. The load-bearing base plate (31) and the connecting base (33) are nested and combined through positioning blocks and positioning grooves.

6. The simulation test device for simulating the underground subway station as described in claim 5, characterized in that: The station arch model includes an arch top structure and a primary support structure. The arch top structure includes an arc-shaped structure (211) and an L-shaped structure (212). The L-shaped structure (212) is fixedly connected to both sides of the arc-shaped structure (211). The primary support structure includes a central partition wall support (221) and a side partition wall support fixedly installed on the lower surface of the arc-shaped structure (211). The side partition wall support is arranged on both sides of the central partition wall support (221). The space between the central partition wall support (221) and the side partition wall support is set as a central guide hole (223). The space between the side partition wall support and the L-shaped structure (212) is set as a side guide hole (224). The bottom of the L-shaped structure (212) is arranged on the top of the load-bearing column (32).

7. The simulation test device for simulating the underground subway station as described in claim 6, characterized in that: Both the central partition wall support (221) and the side partition wall support are provided with evenly arranged connecting holes (225).

8. The simulation test device for simulating the underground subway station as described in claim 7, characterized in that: It is also equipped with a data collection and processing device, which includes a displacement data acquisition device, a stress-strain data acquisition and processing device, and a computer. The displacement data acquisition device is connected to the telescopic displacement gauge via a data cable, and the stress-strain data acquisition and processing device is connected to the strain gauge and the earth pressure cell via a data cable. The displacement data acquisition device and the stress-strain data acquisition and processing device are also connected to the computer via signal.

9. A simulation test method for a subway station built using a cut-and-cover method, characterized in that, The simulation test using the simulation test device for a tunnel-excavated subway station as described in claim 8 includes the following steps: S1, Construction of the simulation experimental setup: The station main body model and station arch model are installed into the assembled model box. At the same time, the backfilling and monitoring device installation are completed. After the soil strength reaches the design data, the front baffle (12) blocking the station main body model and station arch model is removed. S2, First Working Cycle: Excavation of the central tunnels (223) on the left and right sides is carried out. The excavation work of the central tunnels (223) on each side includes at least two excavation stages. After each stage is completed, the excavation space of the central tunnels (223) is lined with gypsum for a second time. After the strength of the gypsum lining meets the set requirements, the next stage of excavation work is carried out. S3, Second Work Cycle: Excavation and excavation of the side guide tunnels (224) on the left and right sides are carried out. The development work of each side guide tunnel (224) includes at least two excavation stages. After each stage is completed, the excavation space of the side guide tunnel (224) is lined with gypsum for a second time. After the strength of the gypsum lining meets the set requirements, the next stage of excavation work is carried out. S4, Excavation of the main structure of the station: After the station arch structure was excavated through the first and second working cycles, the step method was used to excavate the fill in the main model of the station from top to bottom. After each excavation was completed, gypsum was used to line the gap between the two load-bearing columns (32) and form a side wall. S5, Monitoring Data Processing: During steps S2-4, displacement, stress, and strain are monitored using telescopic displacement gauges, strain gauges, and earth pressure cells. Relevant data are collected using displacement data acquisition devices and stress-strain data acquisition devices to plot data change curves based on the excavation stage. Simultaneously, all data are transmitted to a computer in real time for processing and numerical simulation experiments to determine the change status of each data with respect to the tunneling process. S6, Summary of Patterns: Based on step S5, the settlement, stress-strain variation, and upper earth pressure variation of the excavated station arch section under model box test and numerical simulation test are obtained, providing guidance for the engineering design and construction plan of the actual excavated station.

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