Earth pressure balance control method and control system for assisting in shield attitude adjustment

Abstract

The invention relates to an earth pressure balance control method and system for assisting in shield attitude adjustment. The method comprises the steps that historical data are collected, and an earth pressure setting model is constructed; in the tunneling process of the shield tunneling machine, actual construction data, actual ground surface settlement monitoring data and shield tunneling machine tunneling data are obtained in real time; based on the tunneling data of the shield tunneling machine, whether advancing of the current ring is finished or not is judged, if yes, an earth pressure setting model is called, and the earth pressure setting model calculates and outputs a theoretical earth pressure set value of the next ring based on the actual construction data and the actual ground surface settlement monitoring data; whether the elevation of the shield tail is continuously lower than a preset elevation threshold value within a certain time range and cannot be increased or not is judged based on tunneling data of the shield tunneling machine, and if yes, a soil pressure front half ring pressurization mode is started so that the soil pressure set value of the front half ring of the next ring can be automatically pressurized. According to the method, the shield tunneling posture and the earth pressure influence of ground surface settlement are comprehensively considered, and the accuracy of the earth pressure set value is guaranteed.

Description

Technical Field

[0001] This invention relates to the field of tunnel boring machine (TBM) construction technology, and in particular to an earth pressure balance control method and control system for assisting in TBM attitude adjustment. Background Technology

[0002] Shield tunneling is a widely used technique in urban tunnel construction, offering advantages such as high construction efficiency and minimal ground disturbance. It plays a crucial role in tunnel excavation in soft soil strata. Soft soil strata are characterized by high compressibility, high water content, low strength, and high permeability, easily inducing problems such as ground instability, surface settlement, and shield attitude deviation. Surface settlement and the shield's excavation attitude are both important parameters affecting construction quality, directly influencing the excavation trajectory and the final tunnel quality. Therefore, to avoid these potential accidents, it is essential to adjust earth pressure using appropriate methods and use this information to guide construction.

[0003] Current methods for adjusting the earth pressure chamber pressure in shield tunnels include: One method for determining the overburden pressure in a shield tunnel, as disclosed in patent application (CN119623133A), determines the overburden pressure in the shield tunnel based on the formulas for calculating the overburden pressure with respect to the soil arch height and the soil arch height with respect to the stratum loss rate, thereby determining the overburden pressure in the shield tunnel. Another method, a dynamic feedback adjustment method for shield earth pressure balance control, disclosed in patent application (CN105971615A), first determines the soil and water pressure in the excavated stratum and, after correction, uses it as the preset value for the earth pressure chamber pressure. Then, during the shield trial push, surface settlement is monitored in real time, and the obtained data is analyzed for surface settlement. The analysis results are transmitted to the shield control system, and the earth pressure chamber pressure is adjusted to achieve earth pressure balance at the excavation face. For example, the patent application (CN119849683A) discloses an intelligent prediction method for shield tunnel earth chamber pressure. It constructs a hybrid deep learning prediction model and trains a bidirectional prediction model to predict and capture the changing trend of shield tunnel earth chamber pressure from two positive aspects, and predicts the earth chamber pressure value in the shield tunnel area.

[0004] The methods mentioned above only calculate and predict the soil pressure based on historical settlement data, and do not take into account the linkage with the shield tunneling posture. The accuracy of simple calculation and prediction cannot be guaranteed, and there will often be a large deviation in the actual construction process. Furthermore, improper control of soil pressure can lead to the shield posture exceeding the limit and being difficult to adjust. Summary of the Invention

[0005] This invention provides an earth pressure balance control method and control system for assisting in the adjustment of shield tunnel attitude. It comprehensively considers the influence of shield tunneling attitude and ground settlement on earth pressure, ensuring the accuracy of earth pressure setpoint.

[0006] This invention is achieved through the following scheme: an earth pressure balance control method for assisting in shield tunnel attitude adjustment, comprising the following steps:

[0007] S1. Collect historical data and construct an earth pressure setting model based on the historical data. The historical data includes historical construction data, historical surface settlement monitoring data, and historical earth pressure setting manual experience data.

[0008] S2. During the tunnel boring machine's excavation process:

[0009] S2.1. Real-time acquisition of actual construction data, actual surface settlement monitoring data, and tunnel boring machine excavation data;

[0010] S2.2. Based on the tunnel boring machine excavation data, determine whether the current ring advance has ended, and when the current ring advance ends, call the earth pressure setting model, so that the earth pressure setting model calculates and outputs the theoretical earth pressure setting value p0 for the next ring based on the actual construction data and the actual surface settlement monitoring data.

[0011] S2.3. Based on the tunneling data of the tunnel boring machine, determine whether the tail elevation of the shield remains below a preset elevation threshold for a certain period of time and cannot be raised:

[0012] If so, the first half-ring earth pressure setting mode is activated. This first half-ring earth pressure setting mode, when activated, automatically divides the actual earth pressure setting value of the next ring into the first half-ring earth pressure setting value p. 前 and the set value p of the rear half-ring earth pressure 后 And let it be:

[0013] p 前 =p0+Δp

[0014] p 后 =p0

[0015] Where: Δp is the applied pressure value, Δp>0.1;

[0016] If not, the theoretical earth pressure setting value p0 shall be used as the actual earth pressure setting value for the next cycle.

[0017] This invention establishes an earth pressure setting model based on manual experience in setting earth pressure during construction. Combined with the shield tunneling posture, it sets an enableable earth pressure front half-ring pressurization mode, which realizes that the earth pressure setting value is automatically changed according to the progress of the propulsion ring. It comprehensively considers the influence of shield tunneling posture and surface settlement on earth chamber pressure, ensuring the accuracy of earth pressure setting value and avoiding problems such as shield posture exceeding limits and difficulty in adjustment due to inappropriate earth chamber pressure control, and the results output by a single data model being unsuitable for actual construction.

[0018] A further improvement of the earth pressure balance control method for assisting shield tunnel attitude adjustment in this invention lies in that, during the activation of the earth pressure front half-ring pressurization mode, the value of the pressurization value Δp dynamically changes according to a certain change logic, which is as follows:

[0019] When the tail elevation of the shield remains below the preset elevation threshold and continues to descend, the value of the pressurization value Δp increases.

[0020] When the tail elevation of the shield is higher than the preset elevation threshold but lower than the target area, the pressure value Δp decreases, wherein the target area is higher than the preset elevation threshold.

[0021] A further improvement of the earth pressure balance control method for assisting shield tunneling attitude adjustment in this invention is that the historical construction data collected in step S1 includes geological parameters and burial depth parameters, and the constructed earth pressure setting model includes a first setting logic:

[0022] The theoretical earth pressure setpoint p0 for the next ring is calculated based on the earth pressure theory formula, which is:

[0023] p0=k×γ×h

[0024] Wherein: γ is the average unit weight of each soil layer in the advancement section, which can be calculated based on the geological parameters; h is the overburden depth of the earth pressure above the tunnel boring machine, which can be calculated based on the burial depth parameter; k is the earth pressure adjustment coefficient, which is determined based on the surface settlement of the specified measuring points in the surface settlement monitoring data according to human experience.

[0025] A further improvement of the earth pressure balance control method for assisting shield tunnel attitude adjustment in this invention is that the earth pressure setting model constructed in step S1 also includes a second calculation logic:

[0026] Determine if the input surface subsidence monitoring data has been updated:

[0027] If not, then based on the input construction data, determine whether the difference between the burial depth of the next ring and the burial depth of the previous earth pressure ring adjustment exceeds the preset burial depth difference:

[0028] If so, then execute the first calculation logic;

[0029] If not, the theoretical earth pressure setting value of the current ring will be directly used as the theoretical earth pressure setting value of the next ring.

[0030] If so, then retrieve the surface subsidence monitoring data for the specified monitoring point from the input surface subsidence monitoring data, and determine whether the surface subsidence at the specified monitoring point is excessive:

[0031] If so, the earth pressure adjustment coefficient k is adjusted according to human experience, and then the first calculation logic is executed;

[0032] If not, the theoretical earth pressure setting value of the current ring is directly used as the theoretical earth pressure setting value of the next ring.

[0033] A further improvement of the earth pressure balance control method for assisting shield attitude adjustment in this invention is that the method for determining whether the surface settlement at a specified measuring point is too large is as follows: calculate the single change and cumulative change of the surface settlement at the specified measuring point respectively, and comprehensively consider the magnitude of the single change and the cumulative change when making the judgment.

[0034] A further improvement of the earth pressure balance control method for assisting shield tunnel attitude adjustment in this invention is that the geological parameters include a soil borehole table, a soil stratification table, and a soil physical property table.

[0035] A further improvement of the earth pressure balance control method for assisting shield attitude adjustment in this invention is that the designated measuring points include two measuring points in front of the shield machine cut.

[0036] A further improvement of the earth pressure balance control method for assisting shield machine attitude adjustment of the present invention is that the shield machine is equipped with a screw conveyor for balancing earth pressure, and step S2 further includes the following step:

[0037] S2.4. Real-time detection of the actual earth pressure of the tunnel boring machine, comparison of the actual earth pressure set value obtained in step S2.3 with the actual earth pressure, and automatic control of the rotation speed of the screw conveyor based on the comparison result, so that the actual earth pressure is stabilized near the actual earth pressure set value.

[0038] The present invention also provides an earth pressure balance control system for assisting in the adjustment of shield tunnel attitude, used to implement the earth pressure balance control method for assisting in the adjustment of shield tunnel attitude as described above, the earth pressure balance control system comprising:

[0039] The model building module is used to collect historical data and build an earth pressure setting model based on the historical data;

[0040] The data acquisition module is used to acquire and store actual construction data, actual surface settlement monitoring data and tunnel boring machine excavation data in real time. The data acquisition module is connected to the earth pressure setting model.

[0041] The model invocation module is used to determine whether the current ring advance has ended based on the tunneling data of the tunnel boring machine during the tunneling process, and to invoke the earth pressure setting model when the current ring advance ends. The model invocation module is connected to the earth pressure setting model.

[0042] The auxiliary shield attitude adjustment module is used to determine whether to activate the earth pressure front half-ring pressurization mode based on the shield machine tunneling data to judge the shield tail elevation, and finally output the actual earth pressure setting value of the next ring. The auxiliary shield attitude adjustment module is equipped with a program that can realize the earth pressure front half-ring pressurization mode. The auxiliary shield attitude adjustment module is connected to the data acquisition module and the earth pressure setting model.

[0043] A further improvement of the earth pressure balance control system for assisting shield machine attitude adjustment in this invention is that: the shield machine is equipped with a screw conveyor for balancing earth pressure; the earth pressure balance control system also includes an earth pressure balance module for real-time detection of the actual earth pressure of the shield machine, comparing the actual earth pressure setpoint of the next loop with the actual earth pressure, and automatically controlling the rotation speed of the screw conveyor according to the comparison result, so as to stabilize the actual earth pressure near the actual earth pressure setpoint, thereby realizing closed-loop automatic control of earth pressure balance, which is more efficient and accurate than manual control. Attached Figure Description

[0044] Figure 1 A flowchart of the earth pressure balance control method of the present invention is shown.

[0045] Figure 2 A flowchart illustrating the construction process of the earth pressure setting model in this invention is shown.

[0046] Figure 3 The diagram shows the actual application effect of the earth pressure balance control method of the present invention. Detailed Implementation

[0047] To address the inaccuracies of current earth pressure chamber adjustment methods, this invention provides an earth pressure balance control method and system for assisting in shield tunneling attitude adjustment. This method comprehensively considers the influence of shield tunneling attitude and surface settlement on earth pressure chamber pressure, ensuring the accuracy of the earth pressure setpoint. The following detailed description, in conjunction with accompanying drawings, provides further explanation of this earth pressure balance control method and system for assisting in shield tunneling attitude adjustment.

[0048] See Figures 1-2 As shown, an earth pressure balance control method for assisting in shield tunnel attitude adjustment includes the following steps:

[0049] Step S1: Collect historical data and construct an earth pressure setting model based on the historical data.

[0050] Specifically, the historical data includes historical construction data, historical surface settlement monitoring data, and historical earth pressure setting data obtained through manual experience. The historical construction data includes geological parameters and burial depth parameters, with the geological parameters further including soil borehole tables, soil stratification tables, and soil physical property tables. The historical surface settlement monitoring data is monitored at the construction site and automatically uploaded, typically twice a day. The historical earth pressure setting data is based on manual experience determined by on-site technicians through discussions of earth pressure settings. It primarily involves adjusting the theoretical earth pressure setting value calculated by the earth pressure setting model to make the output theoretical earth pressure setting value more accurate. The adjustment amount is determined based on the evaluation of the control effect of previous manually set earth pressure soil samples, and this evaluation relies on feedback from surface settlement monitoring data. Therefore, in this embodiment, the adjustment amount is determined based on the surface settlement situation at specified measuring points in the surface settlement monitoring data, and this adjustment amount is stored as manual experience data to influence the theoretical earth pressure setting value calculated by the earth pressure setting model. The designated measuring points are preferably at least two points in front of the tunnel boring machine (TBM) cut, and the cut location can be obtained by querying the current advance ring number of the TBM and then combining it with the TBM length and segment ring width. All of the above historical data are stored in the database.

[0051] The constructed earth pressure setting model includes a first setting logic, which calculates the theoretical earth pressure setting value p0 for the next stage based on the earth pressure theory formula. This earth pressure theory formula is:

[0052] p0=k×γ×h

[0053] Wherein: γ is the average unit weight of each soil layer in the advancement section, which can be calculated based on the soil borehole table, soil stratification table, and soil physical property table in this geological parameter. h is the overburden depth of the earth pressure above the tunnel boring machine, which can be calculated based on this burial depth parameter, which is obtained by collecting design axis data. k is the earth pressure adjustment coefficient, corresponding to the amount of adjustment to the theoretical earth pressure setpoint mentioned above, which is determined based on the surface settlement of the specified measuring points in the surface settlement monitoring data according to manual experience.

[0054] This earth pressure setting model is established based on manual experience in earth pressure setting during construction (i.e., by introducing an earth pressure adjustment coefficient k), making the theoretical earth pressure setting value p0 calculated by this model more accurate. Considering that the earth pressure setting model is built based on historical data and may not perfectly match actual construction site conditions in practice, to further improve the calculation accuracy of the earth pressure setting model, in some preferred embodiments, a second calculation logic is also included, such as... Figure 2 As shown:

[0055] Determine if the input surface subsidence monitoring data has been updated:

[0056] If not, then based on the input construction data, it is determined whether the difference between the burial depth of the next ring and the burial depth of the previous earth pressure ring adjustment exceeds a preset burial depth difference. This preset burial depth difference is determined according to the actual construction situation. In this embodiment, the preset burial depth difference is 0.05m.

[0057] If so, it means that there is a large difference in burial depth between the upper and lower rings. If the theoretical earth pressure setting value of the current ring is used as the theoretical earth pressure setting value of the next ring, it will no longer be accurate. Therefore, it is necessary to recalculate the theoretical earth pressure setting value of the next ring using the earth pressure theory formula, that is, to execute the first calculation logic.

[0058] If not, it means that there is no significant difference in burial depth between the upper and lower rings, and the theoretical earth pressure setting value of the current ring can be directly used as the theoretical earth pressure setting value of the next ring without recalculation.

[0059] If so, then retrieve the surface subsidence monitoring data for the specified monitoring point from the input surface subsidence monitoring data, and determine whether the surface subsidence at the specified monitoring point is excessive:

[0060] If so, it means that the value of the earth pressure adjustment coefficient k in the earth pressure setting model is not very accurate. It is necessary to adjust the value of the earth pressure adjustment coefficient k according to human experience, and then execute the first calculation logic, that is, recalculate the theoretical earth pressure setting value of the next ring according to the adjusted earth pressure theoretical formula.

[0061] If not, it means that the theoretical earth pressure setting value of the current ring is more in line with the current construction status and can continue to be used. Therefore, the theoretical earth pressure setting value of the current ring is directly used as the theoretical earth pressure setting value of the next ring.

[0062] The method for determining whether the surface subsidence at a specified measuring point is too large is as follows: calculate the single change and cumulative change of surface subsidence at the specified measuring point, and consider the magnitude of the single change and the cumulative change when making the judgment.

[0063] By incorporating this second calculation logic, the earth pressure setting model can be adjusted in real time according to actual construction conditions, rather than using a fixed calculation method to calculate the theoretical earth pressure setting value for each link. This makes the calculation results closer to the actual construction site conditions and further improves the calculation accuracy of the earth pressure setting model.

[0064] Step S2, see Figure 1 and combined Figure 2 As shown, during the tunnel boring machine's excavation process:

[0065] Step S2.1: Real-time acquisition of actual construction data (including geological parameters, burial depth parameters, and human experience data related to earth pressure setting), actual surface settlement monitoring data, and tunnel boring machine excavation data.

[0066] Step S2.2: Based on the tunneling data of the tunnel boring machine, determine whether the current ring advance has ended and entered the assembly state. If so, call the earth pressure setting model, so that the earth pressure setting model calculates and outputs the theoretical earth pressure setting value p0 of the next ring based on the actual construction data and the actual surface settlement monitoring data. For details of the calculation process, see step S1.

[0067] Step S2.3: Based on the tunneling data of the tunnel boring machine, determine whether the tail elevation of the shield remains below a preset elevation threshold for a certain period of time and cannot be raised.

[0068] If so, the first half-ring earth pressure setting mode is activated. This first half-ring earth pressure setting mode, when activated, automatically divides the actual earth pressure setting value of the next ring into the first half-ring earth pressure setting value p. 前 and the set value p of the rear half-ring earth pressure 后 And let it be:

[0069] p 前 =p0+Δp

[0070] p 后 =p0

[0071] Where: Δp is the applied pressure value, Δp>0.1;

[0072] If not, then the theoretical earth pressure setting value p0 shall be used as the actual earth pressure setting value for the next ring.

[0073] This step, based on step S1, combines the shield attitude setting with an enableable earth pressure front half-ring pressurization mode, which can assist the shield attitude in adjusting the theoretical earth pressure setting value output by the earth pressure setting model. This avoids problems such as unsuitable earth chamber pressure control leading to shield attitude exceeding limits and difficulty in adjustment, and the results output by a single data model not being applicable to actual construction. It is especially suitable for situations where the shield tail elevation attitude exceeds limits.

[0074] In some preferred embodiments, when the front half-ring earth pressure pressurization mode is activated, the pressurization value Δp dynamically changes according to a certain logic. This logic is as follows: when the shield tail elevation is continuously below a preset elevation threshold and continues to descend, the pressurization value Δp increases; when the shield tail elevation is above the preset elevation threshold but below the target area, the pressurization value Δp decreases, where the target area is above the preset elevation threshold. This logic can be programmed into the tunnel boring machine's PLC to automatically adjust the theoretical earth pressure setting value when the front half-ring earth pressure pressurization mode is activated. Through this logic, the pressurization value Δp can be dynamically adjusted in close coordination with the shield's attitude, making the final output actual earth pressure setting value more consistent with the actual construction state of the tunnel boring machine, thus making the shield's attitude more stable.

[0075] In some preferred embodiments, the tunnel boring machine (TBM) is equipped with a screw conveyor for balancing earth pressure. Step S2 further includes the following step: Step S2.4, real-time detection of the actual earth pressure on the TBM, comparison of the actual earth pressure setpoint obtained in step S2.3 with the actual earth pressure, and automatic control of the screw conveyor's rotation speed based on the comparison result. When the actual earth pressure setpoint is less than the actual earth pressure, the system increases the screw conveyor's rotation speed to increase the amount of soil discharged; when the actual earth pressure setpoint is greater than the actual earth pressure, the system decreases the screw conveyor's rotation speed to decrease the amount of soil discharged, thus stabilizing the actual earth pressure near the setpoint. This embodiment automatically controls the screw conveyor's rotation speed based on the comparison result to stabilize the actual earth pressure near the setpoint, achieving closed-loop automatic control of earth pressure balancing, which is more efficient and accurate than manual control.

[0076] An earth pressure balance control system for assisting shield tunnel attitude adjustment is provided to implement the earth pressure balance control method for assisting shield tunnel attitude adjustment as described above. The earth pressure balance control system includes a model building module, a data acquisition module, a model calling module, and an auxiliary shield tunnel attitude adjustment module. The system comprises the following modules: a model building module for collecting historical data and constructing an earth pressure setting model based on that data; a data acquisition module for acquiring and storing real-time construction data, actual surface settlement monitoring data, and tunnel boring machine (TBM) excavation data, connected to the earth pressure setting model; a model calling module for determining whether the current ring advance has ended based on the TBM excavation data during the TBM excavation process, and calling the earth pressure setting model when the current ring advance ends, connected to the earth pressure setting model; and an auxiliary TBM attitude adjustment module for determining whether to activate the front half-ring earth pressure setting mode based on the TBM excavation data, and finally outputting the actual earth pressure setting value for the next ring, containing a program to implement the front half-ring earth pressure setting mode, connected to the data acquisition module and the earth pressure setting model.

[0077] Preferably, for cases where a screw conveyor is installed on the tunnel boring machine (TBM): the earth pressure balance control system further includes an earth pressure balance module for real-time detection of the actual earth pressure on the TBM, comparing the actual earth pressure setpoint of the next ring with the actual earth pressure, and automatically controlling the speed of the screw conveyor based on the comparison result to stabilize the actual earth pressure near the setpoint. This earth pressure balance module is connected to the auxiliary TBM attitude adjustment module and the screw conveyor.

[0078] The relationship between the earth pressure front half-ring pressurization mode of this invention and the shield attitude change is verified through a practical engineering case.

[0079] The 174th to 180th rings of this project were advanced using the first half-ring earth pressure method, and the actual advancement effect was as follows: Figure 3 As shown in the figure: the horizontal axis represents the ring number, the black line represents the cut elevation, the red line represents the shield tail elevation, the purple line represents the actual value of the earth pressure in the upper right earth chamber, and the green line represents the actual value of the earth pressure in the upper left earth chamber. The figure shows that the earth pressure in the first half of each ring is higher than in the second half. The shield tail elevation gradually increases from -72mm in ring 174 to -37mm in ring 177, and then stabilizes at around -32mm. This demonstrates the effectiveness of the earth pressure adjustment method in adjusting the shield tail elevation.

[0080] This invention first establishes an earth pressure setting model based on manual experience in setting earth pressure during construction. After the tunnel boring machine (TBM) pushes through one ring, the model reads surface settlement monitoring data to determine if the data has been updated. If updated, it provides the theoretical earth pressure setting value for the next ring based on the data; if not updated, it provides the force earth pressure setting value for the next ring based on the depth change between the previous and next rings. Then, on-site construction personnel can decide whether to use the first half-ring pressurization mode and determine the pressurization value based on the TBM's posture. Finally, the system automatically controls the actual earth chamber pressure based on whether the first half-ring pressurization mode is activated, achieving earth pressure balance.

[0081] The present invention has been described in detail above with reference to the accompanying drawings and embodiments. Those skilled in the art can make various modifications to the present invention based on the above description. Therefore, certain details in the embodiments should not be construed as limiting the present invention, and the scope of protection of the present invention shall be defined by the appended claims.

Claims

1. A method for earth pressure balance control to assist in shield tunnel attitude adjustment, characterized in that, Including the following steps: S1. Collect historical data and construct an earth pressure setting model based on the historical data. The historical data includes historical construction data, historical surface settlement monitoring data, and historical earth pressure setting manual experience data. S2. During the tunnel boring machine's excavation process: S2.

1. Real-time acquisition of actual construction data, actual surface settlement monitoring data, and tunnel boring machine excavation data; S2.

2. Based on the tunnel boring machine excavation data, determine whether the current ring advance has ended, and when the current ring advance ends, call the earth pressure setting model, so that the earth pressure setting model calculates and outputs the theoretical earth pressure setting value p0 for the next ring based on the actual construction data and the actual surface settlement monitoring data. S2.

3. Based on the tunneling data of the tunnel boring machine, determine whether the tail elevation of the shield remains below a preset elevation threshold for a certain period of time and cannot be raised: If so, the first half-ring earth pressure setting mode is activated. This first half-ring earth pressure setting mode, when activated, automatically divides the actual earth pressure setting value of the next ring into the first half-ring earth pressure setting value p. 前 and the set value p of the rear half-ring earth pressure 后 And let it be: p 前 =p0+Δp p after = p0 Where: Δp is the applied pressure value, Δp>0.1; If not, the theoretical earth pressure setting value p0 shall be used as the actual earth pressure setting value for the next cycle.

2. The earth pressure balance control method for assisting shield tunnel attitude adjustment as described in claim 1, characterized in that, When the earth pressure front half-ring pressurization mode is activated, the value of the pressurization Δp changes dynamically according to a certain logic, which is as follows: When the tail elevation of the shield remains below the preset elevation threshold and continues to descend, the value of the pressurization value Δp increases. When the tail elevation of the shield is higher than the preset elevation threshold but lower than the target area, the pressure value Δp decreases, wherein the target area is higher than the preset elevation threshold.

3. The earth pressure balance control method for assisting shield tunnel attitude adjustment as described in claim 1, characterized in that, The historical construction data collected in step S1 includes geological parameters and burial depth parameters. The earth pressure setting model constructed includes a first setting logic: The theoretical earth pressure setpoint p0 for the next ring is calculated based on the earth pressure theory formula, which is: p0=k×γ×h Wherein: γ is the average unit weight of each soil layer in the advancement section, which can be calculated based on the geological parameters; h is the overburden depth of the earth pressure above the tunnel boring machine, which can be calculated based on the burial depth parameter; k is the earth pressure adjustment coefficient, which is determined based on the surface settlement of the specified measuring points in the surface settlement monitoring data according to human experience.

4. The earth pressure balance control method for assisting shield tunnel attitude adjustment as described in claim 3, characterized in that, The earth pressure setting model constructed in step S1 also includes a second calculation logic: Determine if the input surface subsidence monitoring data has been updated: If not, then based on the input construction data, determine whether the difference between the burial depth of the next ring and the burial depth of the previous earth pressure ring adjustment exceeds the preset burial depth difference: If so, then execute the first calculation logic; If not, the theoretical earth pressure setting value of the current ring will be directly used as the theoretical earth pressure setting value of the next ring. If so, then retrieve the surface subsidence monitoring data for the specified monitoring point from the input surface subsidence monitoring data, and determine whether the surface subsidence at the specified monitoring point is excessive: If so, the earth pressure adjustment coefficient k is adjusted according to human experience, and then the first calculation logic is executed; If not, the theoretical earth pressure setting value of the current ring is directly used as the theoretical earth pressure setting value of the next ring.

5. The earth pressure balance control method for assisting shield tunnel attitude adjustment as described in claim 4, characterized in that, The method for determining whether the surface settlement at a specified measuring point is too large is as follows: calculate the single change and cumulative change of surface settlement at the specified measuring point, and consider the magnitude of the single change and the cumulative change when making the judgment.

6. The earth pressure balance control method for assisting shield tunnel attitude adjustment as described in claim 3, characterized in that, The geological parameters include soil borehole tables, soil stratification tables, and soil physical property tables.

7. The earth pressure balance control method for assisting shield tunnel attitude adjustment as described in claim 3, characterized in that, The designated measuring points include two measuring points in front of the tunnel boring machine cut.

8. The earth pressure balance control method for assisting shield tunnel attitude adjustment as described in claim 1, characterized in that, The tunnel boring machine is equipped with a auger for balancing earth pressure. Step S2 also includes the following steps: S2.

4. Real-time detection of the actual earth pressure of the tunnel boring machine, comparison of the actual earth pressure set value obtained in step S2.3 with the actual earth pressure, and automatic control of the rotation speed of the screw conveyor based on the comparison result, so that the actual earth pressure is stabilized near the actual earth pressure set value.

9. An earth pressure balance control system for assisting in the attitude adjustment of a tunnel boring machine, characterized in that, The earth pressure balance control method for implementing the auxiliary shield attitude adjustment as described in any one of claims 1 to 8, wherein the earth pressure balance control system comprises: The model building module is used to collect historical data and build an earth pressure setting model based on the historical data; The data acquisition module is used to acquire and store actual construction data, actual surface settlement monitoring data and tunnel boring machine excavation data in real time. The data acquisition module is connected to the earth pressure setting model. The model invocation module is used to determine whether the current ring advance has ended based on the tunneling data of the tunnel boring machine during the tunneling process, and to invoke the earth pressure setting model when the current ring advance ends. The model invocation module is connected to the earth pressure setting model. The auxiliary shield attitude adjustment module is used to determine whether to activate the earth pressure front half-ring pressurization mode based on the shield machine tunneling data to judge the shield tail elevation, and finally output the actual earth pressure setting value of the next ring. The auxiliary shield attitude adjustment module is equipped with a program that can realize the earth pressure front half-ring pressurization mode. The auxiliary shield attitude adjustment module is connected to the data acquisition module and the earth pressure setting model.

10. The earth pressure balance control system for assisting shield attitude adjustment as described in claim 9, characterized in that: The tunnel boring machine is equipped with a screw conveyor for balancing earth pressure; the earth pressure balance control system also includes an earth pressure balance module for real-time detection of the actual earth pressure of the tunnel boring machine, comparing the actual earth pressure set value of the next ring with the actual earth pressure, and automatically controlling the rotation speed of the screw conveyor according to the comparison result, so as to stabilize the actual earth pressure near the actual earth pressure set value; the earth pressure balance module is connected to the auxiliary shield attitude adjustment module and the screw conveyor.

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