A method and system for designing a pipe segment structure of a ground freezing method ground interface section

Abstract

This invention belongs to the field of shield tunnel engineering technology, specifically providing a design method and system for the underground segment structure of the frozen section. The method includes: simulating the freezing expansion and thawing settlement process using elastic foundation beams of unequal stiffness, and simulating ground constraints using only compressed ground springs, thus establishing a freezing-swelling and thawing settlement model of the tunnel and surrounding rock; establishing a finite element model based on the freezing-swelling and thawing settlement model for simulation calculations; calculating the internal forces of the structure in each segment along the tunnel longitudinal direction, and determining the design parameters of each segment. This scheme is a calculation model for the segment structure during the freezing-swelling and thawing process, which can clarify the stress state of the shield tunnel segment structure during freezing-swelling and thawing settlement, providing a theoretical basis for structural design; simultaneously, it proposes a structural system to reduce the deformation of the shield tunnel segment structure and joints during freezing-swelling and thawing settlement, effectively improving the stress performance of the shield lining segments.

Description

Technical Field

[0001] This invention relates to the field of shield tunnel engineering technology, and more specifically, to a method and system for designing underground segment structures using the freezing method. Background Technology

[0002] With the development of urban transportation and the increasing demand for travel, shield tunneling is trending towards larger, longer, and deeper tunnels. Long-distance shield tunnels pose a severe test to shield tunneling machinery and equipment. Due to environmental limitations such as the width of the Yangtze River, when the tunnel length is long, two shield tunneling machines need to be used to excavate from both ends towards the middle. In order to ensure the construction safety of the soft strata in the docking section, the freezing method is generally adopted to reinforce the strata. The freezing expansion and thawing settlement process will inevitably change the stress state of the existing lining segments in the docking section, which will have an adverse effect on the structural integrity.

[0003] like Figure 4 As shown, two tunnel boring machines (TBMs) are excavating in opposite directions. When the corresponding cutterheads are about to contact, excavation stops, and the areas surrounding each cutterhead are frozen. During the TBM excavation process, the cutterhead excavation causes the upper soil and rock mass to loosen and become porous, while the lower soil and rock mass is relatively dense. This results in the upper area providing less reaction force than the lower area, and the frost heave force is much greater than the soil and rock pressure and structural gravity in the frozen area. Under the action of the frost heave force, the entire TBM exhibits an upward deformation trend.

[0004] like Figure 5 As shown, during the thawing process, due to the thawing of the frozen soil in the lower frozen area, the strength of the rock and soil decreases, the bearing capacity of the foundation decreases, and the shield tunnel as a whole shows a downward deformation trend.

[0005] Whether it is freezing expansion or thawing settlement, it will have an adverse effect on the stress of the existing tunnel segment structure adjacent to the freezing section. At present, there is no corresponding calculation model or design measure or structural system for the freezing and thawing process of the above-mentioned freezing section.

[0006] In summary, during the underground docking process of existing shield tunneling using the freezing method, the freezing of the strata will adversely affect the stress on the structure of the adjacent frozen tunnel segments. Currently, there is no corresponding structural calculation model to simulate its stress mode and stress state, nor are there any targeted design measures or structural systems to reduce the adverse effects of freezing and thawing on the structure. Summary of the Invention

[0007] This invention addresses the technical problem in the prior art that both freezing expansion and thawing settlement processes adversely affect the stress on the existing segment structure adjacent to the frozen section.

[0008] This invention provides a method for designing underground segment structures using the freezing method, comprising the following steps:

[0009] S1, during the freezing expansion and thawing settlement process, an elastic foundation beam with unequal stiffness is used for simulation, and the stratum constraint is simulated using a stratum spring under only compression, to establish a freezing expansion and thawing settlement model of the tunnel and surrounding rock.

[0010] S2, A finite element model is established based on the frost heave-thaw settlement model for simulation calculation;

[0011] S3 calculates the internal forces of the structure in each section along the longitudinal direction of the tunnel and determines the design parameters of the structure in each section.

[0012] Preferably, S1 specifically includes:

[0013] S11, During the freezing expansion process, an elastic foundation beam with unequal stiffness is used for simulation, and the stratum constraint is simulated using a stratum spring that is only under compression. A stratum structure model of the tunnel and the surrounding rock is established. The stratum structure model is subjected to soil and water pressure above and water pressure below.

[0014] S12, during the melting and settlement process, the stratum constraint in the frozen-melting section of the stratum structure model is represented by a nonlinear spring under only compression, simulating the process of the stratum after melting being easily compressible and then difficult to compress; the stratum constraint in the adjacent frozen-melting section is represented by a nonlinear spring under only compression, simulating the two stages before and after the pressure of the shield tunnel sinking on the stratum reaches the bearing capacity of the foundation.

[0015] Preferably, S1 specifically includes:

[0016] The section unaffected by freezing is defined as the normal unreinforced lining section L1, the reinforced lining section affected by freezing is defined as L2, the shield section of the tunnel boring machine is defined as L3, and the frozen section of the stratum is defined as L4. The corresponding stiffness is selected for L1, L2 and L3 according to the actual structural parameters.

[0017] Preferably, S3 specifically includes: during the freezing process, the shield body of the tunnel boring machine in section L4 tends to move upward, and the end movement distance ΔL can be calculated by frost heave or given by empirical value. In the calculation process, by giving a forced displacement ΔL, the internal force of section L2 affected by freezing is obtained, so as to take corresponding reinforcement design measures for L2.

[0018] Preferably, the construction of a reinforcement section structure is included after step S3:

[0019] Based on the internal forces of the lining segments in the connecting section, the required reinforcement, longitudinal through steel plate, and local steel plate dimensions for the corresponding cast-in-place reinforced concrete arc slab are determined.

[0020] After the two tunnel boring machines, which are tunneling in opposite directions, reach the docking area, they will weld longitudinal through steel plates and local steel plates on the area above the lane slabs in different sections.

[0021] Rebar was installed in the area under the lane slab in different sections, longitudinal and circumferential reinforcing bars were laid, and curved slabs were poured.

[0022] After the steel plates are welded and the cast-in-place curved slab reaches the required strength, the freezing construction will proceed.

[0023] Inside the tunnel, the relevant components of the tunnel boring machine were removed, and steel plates were welded to the section without the tunnel boring machine. The unlined section was then constructed based on the calculated parameters.

[0024] Construction of internal structures such as driveway slabs;

[0025] Complete the shield tunneling connection and the construction of the connection section.

[0026] Preferably, S3 specifically includes:

[0027] Above the lane slab, longitudinally, a through-type steel plate is welded to a pre-embedded steel plate on the inner surface of the segment. The specific dimensions of the through-type steel plate are determined based on the calculation results of the frost heave and thaw settlement model. The circumferential joints are secured by welding local steel plates, which are welded to the pre-embedded steel plates on the inner surface of the segment. The specific dimensions of the steel plates are determined based on the seismic calculation results.

[0028] Preferably, S3 specifically includes:

[0029] Below the driveway slab, there is a monolithic cast-in-place reinforced concrete arc slab. The arc slab is connected to the lining by rebar anchoring. The longitudinal reinforcement in the arc slab is determined based on the calculation results of the frost heave and thaw settlement model, and the circumferential reinforcement is determined based on seismic calculations. The reinforcement length of the longitudinal through steel plate, the circumferential partial steel plate and the cast-in-place reinforced concrete arc slab is determined according to the area affected by freezing.

[0030] Preferably, S3 specifically includes:

[0031] Along the longitudinal direction of the tunnel, the middle area is under tension below, and the two end areas are under tension above. In the lower tension area, the arc-shaped plate below the lane slab is equipped with relatively strong longitudinal steel bars to enhance the tensile strength of the lower area, while the longitudinal steel plate above the lane slab is weakened. In the upper tension area, the longitudinal steel plate above the lane slab is strengthened to increase the tensile strength of the upper area, while the lower part of the lane slab is equipped with relatively weak longitudinal steel bars.

[0032] This invention also provides a design system for underground segment joint structures using the freezing method, the system being used to implement the design method for underground segment joint structures using the freezing method, comprising:

[0033] The modeling module is used to simulate the freezing expansion and thawing settlement process using elastic foundation beams with unequal stiffness, and to simulate the ground constraint using ground springs under only compression, thus establishing a freezing expansion and thawing settlement model of the tunnel and surrounding rock.

[0034] The simulation calculation module is used to establish a finite element model based on the frost heave and thaw settlement model for simulation calculation.

[0035] The docking structure design module is used to calculate the internal forces of the structure in each section along the longitudinal direction of the tunnel and determine the design parameters of each section.

[0036] The present invention also provides an electronic device, including a memory and a processor, wherein the processor is used to execute a computer management program stored in the memory to implement the steps of the frozen ground docking segment structure design method.

[0037] Beneficial Effects: This invention provides a design method and system for tunnel segment structures using the freezing method in the ground. The method includes: simulating the freezing expansion and thawing settlement process using elastic foundation beams of unequal stiffness, and simulating ground constraints using only compressed ground springs to establish a freezing expansion and thawing settlement model between the tunnel and surrounding rock; establishing a finite element model based on the freezing expansion and thawing settlement model for simulation calculations; calculating the internal forces of the structure in each segment along the tunnel longitudinal direction, and determining the design parameters of each segment. This scheme is a calculation model for tunnel segment structures during the freezing expansion and thawing process, which can clarify the stress state of the shield tunnel segment structure during freezing expansion and thawing settlement, providing a theoretical basis for structural design; simultaneously, it proposes a structural system to reduce the deformation of the shield tunnel segment structure and joints during freezing expansion and thawing settlement, which can effectively improve the stress performance of the shield lining segments. Attached Figure Description

[0038] Figure 1 A flowchart of a method for designing underground segment structures using the freezing method is provided by this invention.

[0039] Figure 2 A schematic diagram of the hardware structure of a possible electronic device provided by the present invention;

[0040] Figure 3 A schematic diagram of the hardware structure of a possible computer-readable storage medium provided by the present invention;

[0041] Figure 4 This is a schematic diagram of shield tunneling during the freezing and expansion process of the strata in the background art of this invention.

[0042] Figure 5 This is a schematic diagram of shield tunneling during the strata ablation and settlement process using the freezing method in the background art of this invention.

[0043] Figure 6 A schematic diagram of the calculation model for the freezing expansion process provided by this invention;

[0044] Figure 7 This is a schematic diagram of the calculation model for the ablation and sedimentation process provided by the present invention;

[0045] Figure 8This is a schematic diagram of the longitudinal bending moment along the tunnel provided by the present invention;

[0046] Figure 9 This is a schematic cross-sectional view of the lower tension zone structural system provided by the present invention;

[0047] Figure 10 This is a schematic cross-sectional view of the upper tension zone structural system provided by the present invention;

[0048] Figure 11 A plan view of the welded steel plate area above the lane plate provided by the present invention;

[0049] Figure 12 The plan view of the cast-in-place curved slab area below the lane slab provided by the present invention.

[0050] Explanation of reference numerals in the attached figures:

[0051] Existing segments 1, strong longitudinal reinforcement 2, weak steel plate 3, anchoring 4, curved plate 5, lane slab 6, longitudinal reinforcement 7, circumferential reinforcement 8, manhole 9, longitudinal steel plate 10, circumferential steel plate 11. Detailed Implementation

[0052] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0053] Combination Figures 1-12 This invention provides a method for designing underground segment structures using the freezing method, comprising the following steps:

[0054] S1, during the freezing expansion and thawing settlement process, an elastic foundation beam with unequal stiffness is used for simulation, and the stratum constraint is simulated using a stratum spring under only compression, to establish a freezing expansion and thawing settlement model of the tunnel and surrounding rock; since the structural strength of different sections is different, and the force received is also different due to the different distances from the joint, it is necessary to use structures with different stiffnesses to perform equivalent modeling of the sections.

[0055] S2. A finite element model is established based on the frost heave and thaw settlement model for simulation calculation. The displacement that will actually occur in the two different stages of freezing expansion and thawing settlement can be obtained through frost heave calculation or experience. Then, the displacement is applied to the model for simulation calculation, so that the internal forces in different sections can be obtained.

[0056] S3 calculates the internal forces of the structure in each section along the longitudinal direction of the tunnel, and determines the design parameters of each section. Once the internal forces are determined, the structural design of the corresponding section can be carried out.

[0057] like Figure 6As shown, the freezing and expansion process is simulated using elastic foundation beams with unequal stiffness, while the ground constraint is simulated using ground springs under compression only. A ground structure model of the tunnel and surrounding rock is established, and the ground displacement under different stress states is calculated. By using the correspondence between force and displacement, the specific parameters of the ground springs at different stages are calculated. The structure is subjected to soil and water pressure above and water pressure below.

[0058] L1 is the normal, unreinforced lining section (the freezing process has no impact on this section), L2 is the reinforced lining section affected by freezing, and L3 is the shield body section of the tunnel boring machine. Due to differences in structural form and reinforcement methods, the stiffness of L1, L2, and L3 differs and is selected based on actual structural parameters. L4 is the frozen section. During the freezing process, the shield body in this section tends to move upwards. The end movement distance ΔL can be calculated using frost heave or assigned an empirical value. The calculation process involves assigning a forced displacement ΔL to obtain the internal forces in the frozen section L2, so as to take reasonable reinforcement design measures for L2.

[0059] After freezing and expansion, as Figure 7 As shown, the process enters the melting and settlement phase. During this process, elastic foundation beams with unequal stiffness are used for simulation, and ground constraints are simulated using ground springs under only compression. A ground structure model of the tunnel and surrounding rock is established, and ground displacements under different stress states are calculated. By using the correspondence between force and displacement, the specific parameters of the ground springs at different stages are calculated.

[0060] In the frozen-thawed section L4 (i.e., the frozen section during the freeze-expansion process), the ground constraint is represented by a nonlinear spring under compression only, simulating the process of the thawed ground being initially easily compressible and then difficult to compress. The ground constraint in the adjacent frozen-thawed section is also represented by a nonlinear spring under compression only, simulating two stages: before and after the pressure exerted by the tunnel boring machine (TBM) reaches the foundation bearing capacity. Earth pressure is generated in the ablation and loosening zone L4 above the structure. In the section L5 without the TBM, steel plates are welded to the TBM shell, and the stiffness of the welded section is selected based on actual parameters.

[0061] After the above two stages are completed, the final model is obtained. The internal forces of each section are calculated through simulation, so that reasonable reinforcement or design measures can be taken for each section.

[0062] The lining ring pipe segment structure system of the docking section consists of lining pipe segments, longitudinal steel bars 7, cast-in-place arc plate 5, anchor bars 4, steel plates welded along the longitudinal direction of the tunnel, and steel plates welded along the circumferential direction of the tunnel.

[0063] For sections 6 and above, where space for vehicle and equipment layout is limited, a through-type steel plate is welded longitudinally to a pre-embedded steel plate on the inner surface of the segment. The specific dimensions of the through-type steel plate are determined based on calculations using a frost heave and thaw settlement model. Simultaneously, the through-type steel plate should avoid manhole 9.

[0064] Above lane slab 6, the joints along the circumference are secured with welded local steel plates. The circumferential steel plate 11 is welded to the embedded steel plate on the inner surface of the segment. The specific dimensions of the steel plate are determined based on the seismic calculation results.

[0065] Below lane slab 6, there is a cast-in-place reinforced concrete arc slab 5. The arc slab 5 is connected to the lining by rebar 4 (using connectors when available). The longitudinal rebar 7 in the arc slab 5 is determined based on the calculation results of the frost heave and thaw settlement model, and the circumferential rebar is determined based on seismic calculations. The reinforcement length of the longitudinal through steel plate, the circumferential steel plate 11, and the cast-in-place reinforced concrete arc slab 5 is determined based on the area affected by freezing.

[0066] Along the longitudinal direction of the tunnel, the overall bending moment of the structure is as follows Figure 8 As shown, the middle area is under tension below, and the two end areas are under tension above; the specific size of these areas depends on the calculation results. In the lower tension area, the curved plate 5 below the lane slab 6 should be reinforced with strong longitudinal steel bars 7 (i.e., strong longitudinal reinforcement) to enhance the tensile strength of the lower area. The strength of the longitudinal steel plate 10 above the lane slab 6 should be weakened. Figure 9 As shown, a weak steel plate 3 is used; in the upper tension area, the longitudinal steel plate 10 above the lane slab 6 should be strengthened to increase the tensile strength of the upper area, and a weaker longitudinal steel bar 7 is arranged below the lane slab 6, such as... Figure 10 As shown.

[0067] After designing the parameters for each section, construction of the reinforced section structure began:

[0068] (1) In the area where steel plates need to be welded in the frozen section, steel plates are pre-embedded in the lining segments, i.e., the existing segments 1, during the fabrication of the lining segments.

[0069] (2) Using the calculation model provided by the present invention, the dimensions of the required reinforcement, longitudinal through steel plate, and local steel plate of the corresponding cast-in-place reinforced concrete arc plate 5 are obtained according to the size of the internal force of the lining segment structure of the connecting section.

[0070] (3) After the two tunnel boring machines that are tunneling in opposite directions arrive at the docking area, longitudinal through steel plates and local steel plates are welded on the area above the lane slab 6 in different sections.

[0071] (4) Install rebar 4 in the area below the lane slab 6 in different sections, lay longitudinal steel bars 7 and circumferential steel bars, and pour arc slab 5.

[0072] (5) After the steel plate welding is completed and the strength of the cast-in-place arc plate 5 reaches the requirements, the freezing construction will be carried out;

[0073] (6) Remove the relevant components of the tunnel boring machine inside the tunnel, use steel plates to weld the section without the tunnel boring machine, and carry out the construction of the unlined section according to the calculated parameters.

[0074] (7) Construction of the internal structure of lane slab 6, etc.;

[0075] (8) Complete the shield docking and docking section construction.

[0076] Beneficial effects:

[0077] This invention proposes a longitudinal calculation model and structural system for the underground tunnel segment structure using the freezing method. This model can reveal the stress state of the shield tunnel segment structure during frost heave and thaw settlement, providing a theoretical basis for structural design. At the same time, it proposes a structural system to reduce the deformation of the shield tunnel segment structure and joints during frost heave and thaw settlement, which can effectively improve the stress performance of the shield lining segments.

[0078] This invention also provides a system for designing underground segment structures using the freezing method, the system being used to implement the aforementioned method for designing underground segment structures using the freezing method, comprising:

[0079] The modeling module is used to simulate the freezing expansion and thawing settlement process using elastic foundation beams with unequal stiffness, and to simulate the ground constraint using ground springs under only compression, thus establishing a freezing expansion and thawing settlement model of the tunnel and surrounding rock.

[0080] The simulation calculation module is used to establish a finite element model based on the frost heave and thaw settlement model for simulation calculation.

[0081] The docking structure design module is used to calculate the internal forces of the structure in each section along the longitudinal direction of the tunnel and determine the design parameters of each section.

[0082] Please see Figure 2 This is a schematic diagram illustrating an embodiment of the electronic device provided in this invention. For example... Figure 2 As shown, an embodiment of the present invention provides an electronic device, including a memory 1310, a processor 1320, and a computer program 1311 stored in the memory 1310 and executable on the processor 1320. When the processor 1320 executes the computer program 1311, it performs the following steps: S1, during the freezing expansion and thawing settlement process, an elastic foundation beam with unequal stiffness is used for simulation, and the stratum constraint is simulated using a stratum spring that is only under compression, thereby establishing a freezing expansion and thawing settlement model of the tunnel and the surrounding rock.

[0083] S2, A finite element model is established based on the frost heave-thaw settlement model for simulation calculation;

[0084] S3 calculates the internal forces of the structure in each section along the longitudinal direction of the tunnel and determines the design parameters of the structure in each section.

[0085] Please see Figure 3 This is a schematic diagram illustrating an embodiment of a computer-readable storage medium provided by the present invention. (See diagram below.) Figure 3As shown, this embodiment provides a computer-readable storage medium 1400, on which a computer program 1411 is stored. When the computer program 1411 is executed by the processor, it performs the following steps: S1, during the freezing expansion and thawing settlement process, an elastic foundation beam with unequal stiffness is used for simulation, and the stratum constraint is simulated using a stratum spring that is only under compression, thereby establishing a freezing expansion and thawing settlement model of the tunnel and the surrounding rock.

[0086] S2, A finite element model is established based on the frost heave-thaw settlement model for simulation calculation;

[0087] S3 calculates the internal forces of the structure in each section along the longitudinal direction of the tunnel and determines the design parameters of the structure in each section.

[0088] It should be noted that the descriptions of each embodiment in the above embodiments have different focuses. For parts that are not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0089] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0090] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for designing underground segment structures using the freezing method, characterized in that, Includes the following steps: S1, during the freezing expansion and thawing settlement process, an elastic foundation beam with unequal stiffness is used for simulation, and the stratum constraint is simulated using a stratum spring under only compression, to establish a freezing expansion and thawing settlement model of the tunnel and surrounding rock. S2, A finite element model is established based on the frost heave-thaw settlement model for simulation calculation; S3, calculate the internal forces of the structure in each section along the longitudinal direction of the tunnel, and determine the design parameters of the structure in each section; Specifically, S1 includes: S11, During the freezing expansion process, an elastic foundation beam with unequal stiffness is used for simulation, and the stratum constraint is simulated using a stratum spring that is only under compression. A stratum structure model of the tunnel and the surrounding rock is established. The stratum structure model is subjected to soil and water pressure above and water pressure below. S12, during the melting and settlement process, the stratum constraint in the frozen-melting section of the stratum structure model is represented by a nonlinear spring under only compression, simulating the process of the stratum after melting being easily compressible and then difficult to compress; the stratum constraint in the adjacent frozen-melting section is represented by a nonlinear spring under only compression, simulating the two stages before and after the pressure of the shield tunnel sinking on the stratum reaches the bearing capacity of the foundation.

2. The method for designing underground segment structures using the freezing method according to claim 1, characterized in that, S1 specifically includes: The section unaffected by freezing is defined as the normal unreinforced lining section L1, the reinforced lining section affected by freezing is defined as L2, the shield section of the tunnel boring machine is defined as L3, and the frozen section of the stratum is defined as L4. The corresponding stiffness is selected for L1, L2 and L3 according to the actual structural parameters.

3. The method for designing underground segment structures using the freezing method according to claim 2, characterized in that, S3 specifically includes: during the freezing process, the shield of the tunnel boring machine in section L4 tends to move upward. The end movement distance ΔL can be calculated by frost heave or given by empirical value. In the calculation process, by giving a forced displacement ΔL, the internal force of section L2 affected by freezing is obtained so that corresponding reinforcement design measures can be taken for L2.

4. The method for designing underground segment structures using the freezing method according to claim 1, characterized in that, The construction of the reinforcement section structure is also included after S3: Based on the internal forces of the lining segments in the connecting section, the required reinforcement, longitudinal through steel plate, and local steel plate dimensions for the corresponding cast-in-place reinforced concrete arc slab are determined. After the two tunnel boring machines, which are tunneling in opposite directions, reach the docking area, they will weld longitudinal through steel plates and local steel plates on the area above the lane slabs in different sections. Rebar was installed in the area under the lane slab in different sections, longitudinal and circumferential steel bars were laid, and curved slabs were poured. After the steel plates are welded and the cast-in-place curved slab reaches the required strength, the freezing construction will proceed. Inside the tunnel, the relevant components of the tunnel boring machine were removed, and steel plates were welded to the section without the tunnel boring machine. The unlined section was then constructed based on the calculated parameters. Construction of internal structures such as driveway slabs; Complete the shield tunneling connection and the construction of the connection section.

5. The method for designing underground segment structures using the freezing method according to claim 1, characterized in that, S3 specifically includes: Above the lane slab, longitudinally, a through-type steel plate is welded to a pre-embedded steel plate on the inner surface of the segment. The specific dimensions of the through-type steel plate are determined based on the calculation results of the frost heave and thaw settlement model. The circumferential joints are secured by welding local steel plates, which are welded to the pre-embedded steel plates on the inner surface of the segment. The specific dimensions of the steel plates are determined based on the seismic calculation results.

6. The method for designing underground segment structures using the freezing method according to claim 1, characterized in that, S3 specifically includes: Below the driveway slab, there is a monolithic cast-in-place reinforced concrete arc slab. The arc slab is connected to the lining by rebar anchoring. The longitudinal reinforcement in the arc slab is determined based on the calculation results of the frost heave and thaw settlement model, and the circumferential reinforcement is determined based on seismic calculations. The reinforcement length of the longitudinal through steel plate, the circumferential partial steel plate and the cast-in-place reinforced concrete arc slab is determined according to the area affected by freezing.

7. The method for designing underground segment structures using the freezing method according to claim 1, characterized in that, S3 specifically includes: Along the longitudinal direction of the tunnel, the middle area is under tension below, and the two end areas are under tension above. In the lower tension area, the arc-shaped plate below the lane slab is equipped with relatively strong longitudinal steel bars to enhance the tensile strength of the lower area, while the longitudinal steel plate above the lane slab is weakened. In the upper tension area, the longitudinal steel plate above the lane slab is strengthened to increase the tensile strength of the upper area, while the lower part of the lane slab is equipped with relatively weak longitudinal steel bars.

8. A design system for underground segment connection structure using the freezing method, characterized in that, The system is used to implement the design method for the underground segment connection structure using the freezing method as described in any one of claims 1-7, including: The modeling module is used to simulate the freezing expansion and thawing settlement process using elastic foundation beams with unequal stiffness, and to simulate the ground constraint using ground springs under only compression, thus establishing a freezing expansion and thawing settlement model of the tunnel and surrounding rock. The simulation calculation module is used to establish a finite element model based on the frost heave and thaw settlement model for simulation calculation. The docking structure design module is used to calculate the internal forces of the structure in each section along the longitudinal direction of the tunnel and determine the design parameters of each section.

9. An electronic device, characterized in that, It includes a memory and a processor, wherein the processor is used to execute computer management programs stored in the memory to implement the steps of the frozen ground docking segment structure design method as described in any one of claims 1-7.

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