Control method for continuous damage of shield tunnel

Abstract

The invention relates to the technical field of shield tunnel engineering, and discloses a control method for continuous damage of a shield tunnel. Determining a damage range threshold value of the current shield tunnel according to the burial depth and the outer diameter of the current shield tunnel; based on the occurrence position, determining the position of a key ring and the critical length of a reinforcing unit according to a shield tunnel continuous damage control strategy; and in the extension direction of the shield tunnel, reinforcing units with the reinforcing unit critical length are arranged at the positions of the corresponding key rings on the two sides of the occurrence position correspondingly, and continuous damage of the shield tunnel is controlled. The reinforcing units with the reinforcing unit critical length are arranged at the positions of the key rings, continuous damage of the shield tunnel is controlled, and the control effect is improved.

Description

Technical Field

[0001] The present application relates to the technical field of shield tunnel engineering, and in particular to a method for controlling continuous destruction of a shield tunnel. Background Art

[0002] Shield tunnels are widely used in subways, railways and cross-river transportation due to their high cost-effectiveness, low environmental impact and fast construction speed. Shield tunnels are composed of thousands of bolted segments, which form thousands of joints between the segments. Unlike continuous pipes, the presence of a large number of joints in shield tunnels significantly reduces its structural integrity and greatly weakens the integrity of the tunnel.

[0003] Although the shield tunnel is designed with safety redundancy to ensure that each pipe ring operates under predetermined conditions. However, when unexpected risks and uncertainties arise, the tunnel may be subjected to abnormal loads, increasing the possibility of damage. This may lead to large-scale damage and cause significant property losses. Existing studies on accidents in shield tunnels have shown that shield tunnels may suffer continuous damage due to local small damage, and the main damage to shield tunnels occurs at the joints rather than the segments themselves. However, the impact of tunnel joints has not been considered in existing studies on damage control of shield tunnels.

[0004] Therefore, there is an urgent need for a control method for continuous destruction of shield tunnels, which can control continuous destruction based on tunnel joints and improve the control effect. Summary of the invention

[0005] In order to solve the above technical problems, the present application provides a method for controlling continuous destruction of a shield tunnel, comprising the following steps: Get the current shield tunnel's buried depth and outer diameter; Determine the damage range threshold of the current shield tunnel by the buried depth and outer diameter of the current shield tunnel; the damage range threshold is used to indicate the minimum number of damaged segment rings that cause continuous damage under the current buried depth and outer diameter; Obtain the location of the current initial local damage in the shield tunnel and the number of damaged segments; If the number of damaged segments exceeds the damage range threshold, based on the occurrence location and in accordance with the shield tunnel continuous damage control strategy, the location of the critical ring and the critical length of the reinforcement unit are determined; the location of the critical ring is the location where the reinforcement unit is set; and the critical length of the reinforcement unit is the number of rings of the reinforcement unit; Along the extension direction of the shield tunnel, on both sides of the occurrence position, reinforcement units with critical lengths are respectively arranged at the positions of corresponding key rings to control the continuous destruction of the shield tunnel.

[0006] Furthermore, the method for obtaining the continuous destruction control strategy of the shield tunnel is: Collect relevant data of shield tunnels that have been continuously damaged in the past; the relevant data of shield tunnels that have been continuously damaged in the past include the buried depth of the shield tunnel, the outer diameter of the shield tunnel, the position of the key ring and the critical length of the reinforcement unit; By means of numerical simulation, continuous destruction of a shield tunnel is simulated to obtain relevant data of the shield tunnel in which continuous destruction is simulated; the relevant data of the shield tunnel in which continuous destruction is simulated include the buried depth of the shield tunnel, the outer diameter of the shield tunnel, the position of the key ring and the critical length of the reinforcement unit; A control strategy correspondence table is prepared based on the relevant data of the shield tunnels that have been continuously damaged in the past and the relevant data of the shield tunnels that have been simulated to be continuously damaged; the control strategy correspondence table is the correspondence between the buried depth of each shield tunnel and the outer diameter of the shield tunnel and the position of each key ring and the critical length of the reinforcement unit; The control strategy correspondence table is used as the shield tunnel continuous destruction control strategy.

[0007] Furthermore, the method for obtaining the continuous destruction control strategy of the shield tunnel is: Collect relevant data of shield tunnels that have been continuously damaged in the past; the relevant data of shield tunnels that have been continuously damaged in the past include the buried depth of the shield tunnel, the outer diameter of the shield tunnel, the position of the key ring and the critical length of the reinforcement unit; By means of numerical simulation, continuous destruction of a shield tunnel is simulated to obtain relevant data of the shield tunnel in which continuous destruction is simulated; the relevant data of the shield tunnel in which continuous destruction is simulated include the buried depth of the shield tunnel, the outer diameter of the shield tunnel, the position of the key ring and the critical length of the reinforcement unit; According to the relevant data of the shield tunnels that have been continuously damaged in history and the relevant data of the shield tunnels that have been simulated to be continuously damaged, a control strategy fitting formula is obtained; the control strategy fitting formula is used to express the fitting relationship between the buried depth of each shield tunnel and the outer diameter of the shield tunnel and the position of each key ring and the critical length of the reinforcement unit; The control strategy fitting formula is used as the shield tunnel continuous destruction control strategy.

[0008] Furthermore, the method for obtaining the continuous destruction control strategy of the shield tunnel is: Collect relevant data of shield tunnels that have been continuously damaged in the past; the relevant data of shield tunnels that have been continuously damaged in the past include the buried depth of the shield tunnel, the outer diameter of the shield tunnel, the position of the key ring and the critical length of the reinforcement unit; By means of numerical simulation, continuous destruction of a shield tunnel is simulated to obtain relevant data of the shield tunnel in which continuous destruction is simulated; the relevant data of the shield tunnel in which continuous destruction is simulated include the buried depth of the shield tunnel, the outer diameter of the shield tunnel, the position of the key ring and the critical length of the reinforcement unit; Using the relevant data of the shield tunnel that has been continuously destroyed in history and the relevant data of the shield tunnel that has been simulated to be continuously destroyed as a training set; Construct a control strategy model; use the buried depth of the shield tunnel and the outer diameter of the shield tunnel as the input of the control strategy model, and use the position of the key ring and the critical length of the reinforcement unit as the output of the control strategy model; Using the training set to train the control strategy model; Based on the trained control strategy model, the continuous destruction control strategy of the shield tunnel is output.

[0009] Furthermore, the continuous destruction boundary caused by the initial local destruction is used as the position of the critical ring.

[0010] Furthermore, reinforcement units with critical lengths are respectively arranged at the positions of the corresponding key rings to control the continuous destruction of the shield tunnel, specifically: At the position of the key ring, reinforcing units are arranged both close to the initial local failure direction and away from the initial local failure direction; the sum of the number of rings of the reinforcing units arranged is the critical length of the reinforcing units.

[0011] Furthermore, the destruction range threshold of the current shield tunnel is determined by the buried depth and outer diameter of the current shield tunnel, specifically: By collecting historical data or using a numerical simulation method, a damage range threshold relationship is determined; the damage range threshold relationship is used to represent the corresponding relationship between the buried depth and outer diameter of each shield tunnel and the damage range threshold; According to the buried depth and outer diameter of the current shield tunnel, the damage range threshold relationship is found to determine the damage range threshold of the current shield tunnel.

[0012] Furthermore, the reinforcement operation of the reinforcement unit includes an inter-ring reinforcement operation of the tunnel segment and an intra-ring reinforcement operation of the tunnel segment.

[0013] On the other hand, the present application also provides a control system for continuous destruction of a shield tunnel, which executes a control method for continuous destruction of a shield tunnel as described in any one of the above items, and the control system includes a destruction range threshold module, a current shield tunnel information acquisition module, and a continuous destruction control strategy output module: A damage range threshold module is used to obtain the buried depth and outer diameter of the current shield tunnel; the damage range threshold of the current shield tunnel is determined by the buried depth and outer diameter of the current shield tunnel; the damage range threshold is used to represent the minimum number of damaged segment rings that cause continuous damage under the current buried depth and outer diameter; The current shield tunnel information acquisition module is used to obtain the location of the current initial local damage in the shield tunnel and the number of damaged segments; The continuous damage control strategy output module determines the position of the key ring and the critical length of the reinforcement unit based on the occurrence location and the continuous damage control strategy of the shield tunnel if the number of damaged segment rings exceeds the damage range threshold; the position of the key ring is the position where the reinforcement unit is set; and the critical length of the reinforcement unit is the number of rings of the reinforcement unit.

[0014] The embodiments of the present application have the following technical effects: The present application provides a method for controlling continuous destruction of a shield tunnel, proposes the position of a critical ring and the critical length of a reinforcement unit, and determines the position of the critical ring and the critical length of the reinforcement unit according to the continuous destruction control strategy of the shield tunnel. That is, reinforcement units with a critical length of the reinforcement unit are set at the position of the critical ring to control the continuous destruction of the shield tunnel and improve the control effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0016] Figure 1 It is a flowchart of the steps of a method for controlling continuous destruction of a shield tunnel provided in an embodiment of the present application; Figure 2 It is a schematic diagram of the impact range of adjacent rings caused by continuous destruction provided by an embodiment of the present application; Figure 3 The embodiment of the present application provides S EU_1 Model and S EU_2 Schematic diagram of the reinforcement unit setup of the model; Figure 4 The embodiment of the present application provides S EU_1 Model and S EU_2 Schematic diagram of the control effect after the model's enhanced unit is set; Figure 5 It is S provided in the embodiment of the present application EU_3 Schematic diagram of the model’s settings and control effects; Figure 6 It is S provided in the embodiment of the present application EU_4 Schematic diagram of the model’s settings and control effects; Figure 7 It is S provided in the embodiment of the present application EU_5 Model and S EU_6 Schematic diagram of the model's settings and control effects. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solution and advantages of the present application clearer, the technical solution of the present application will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work belong to the scope of protection of the present application.

[0018] The continuous failure of shield tunnels is related to the tunnel burial depth and the scope of local failure, but the continuous failure process of tunnels under different conditions is similar. The continuous failure process in tunnels can be summarized into four stages, namely "collapse of local failure ring", "failure of inter-ring joints", "failure of joints inside the rings" and "termination of continuous failure". After local failure, the local failure ring collapses under the action of earth pressure, causing the soil outside the tunnel to flow into the tunnel. Under the influence of the movement of the soil outside the tunnel, the tension in the internal force of the inter-ring joints between the tunnel pipe rings increases, resulting in the failure of the inter-ring joints. After the failure of the inter-ring joints, the integrity of the tunnel is reduced. Under the combined influence of the gravity of the soil inside the tunnel and the unloading effect of the soil outside the tunnel, the joint inside the tunnel ring is damaged. As the soil flowing into the tunnel gradually stabilizes, the external load on the tunnel structure gradually stabilizes, and the continuous failure of the tunnel also stops. The above four stages can comprehensively summarize the development process of continuous failure of tunnels. Under certain conditions, the above four stages may not all appear in the continuous failure process, but the order of the four stages is certain.

[0019] Based on the problem that the damage control of existing shield tunnels does not consider the influence of tunnel joints, the present application provides a method for controlling the continuous damage of a shield tunnel. Figure 1 It can be seen that the following steps are included: S1: Get the buried depth and outer diameter of the current shield tunnel; The outer diameter of the shield tunnel is represented by D. To simplify the record, the outer diameter of the shield tunnel is used as the unit of burial depth, that is, the burial depth of the shield tunnel is XD, where X can be 1, 2, ... S2: Determine the damage range threshold of the current shield tunnel based on the buried depth and outer diameter of the current shield tunnel; the damage range threshold is used to indicate the minimum number of damaged segments that cause continuous damage under the current buried depth and outer diameter; In some embodiments, the destruction range threshold of the current shield tunnel is determined by the buried depth and outer diameter of the current shield tunnel; specifically: By collecting historical data or numerical simulation methods, the damage range threshold relationship is determined; the damage range threshold relationship is used to express the corresponding relationship between the buried depth and outer diameter of each shield tunnel and the damage range threshold; According to the buried depth and outer diameter of the current shield tunnel, the damage range threshold relationship is found to determine the damage range threshold of the current shield tunnel.

[0020] For example, the impact range of adjacent rings affected by continuous damage in the numerical simulation model is summarized. Figure 2 As shown in the figure, the tunnel is buried at a depth of 2D, and the initial local damage range is 2.5 rings. After the local damage occurs, the adjacent structure is not affected by the continuous damage. The local damage range increases to 5.5 rings, and the adjacent rings of the local damage ring are affected by the continuous damage. The adjacent ring failure range is 1 ring, that is, when the tunnel is buried at a depth of 2D and the initial local damage range is 5.5 rings, the number of failed rings is 6.5. Therefore, at a certain depth and outer diameter of a shield tunnel, there is a damage range threshold (threshold tIDS) for whether the adjacent rings will be affected by the continuous damage. When the number of damaged segments of the current initial local damage is greater than or equal to the threshold tIDS, the adjacent ring structure will be affected by the continuous damage, that is, the continuous damage of the tunnel will expand along the axial direction of the tunnel. For example, when the tunnel is buried at a depth of 2D, the threshold tIDS is 5.5.

[0021] The impact range of continuous damage in tunnels is related to the tunnel burial depth and local damage range. When the tunnel burial depth is constant, the larger the local damage range, the larger the impact range of continuous damage, and the more failure rings caused by continuous damage; when the local damage range is constant, the greater the tunnel burial depth, the greater the impact of continuous damage, and the more failure rings caused by continuous damage. Therefore, the greater the tunnel burial depth and the larger the initial local damage range, the smaller the ability of the tunnel structure to resist continuous damage. According to the analysis of continuous damage of tunnels under different conditions, it can be concluded that when the tunnel burial depth is constant, there is a damage range threshold related to the burial depth and outer diameter of the shield tunnel for whether the adjacent ring will be affected by continuous damage. When the tunnel burial depth is large, local damage in a smaller range may cause large-scale continuous damage in the tunnel. With the continuous development of underground space, the tunnel burial depth is getting larger and larger. Therefore, when constructing tunnels, especially when constructing connecting passages, strict attention should be paid to avoid local damage in the tunnel and causing large-scale continuous damage.

[0022] S3: Obtain the location of the current initial local damage in the shield tunnel and the number of damaged segments; illustratively, it can be obtained by geological radar method.

[0023] S4: If the number of damaged segments exceeds the damage range threshold, the location of the critical ring and the critical length of the reinforcement unit are determined based on the occurrence location and the shield tunnel continuous damage control strategy; the location of the critical ring is the location where the reinforcement unit is set; the critical length of the reinforcement unit is the number of rings of the reinforcement unit; Exemplarily, the present application digitally simulates a shield tunnel. Based on the symmetry of the tunnel, 50.5 ring segments are constructed in the model, and the length of the first ring is half the length of the other rings. The interaction between the soil and the tunnel structure is implemented by a "general contact" algorithm based on the penalty contact method. The friction coefficient between the soil and the concrete segments is taken as 0.4. The interaction between adjacent segments (i.e., the behavior of the tunnel joints) is modeled by connectors. In the numerical model of this study, the bolts connecting adjacent segments are not considered. Two types of connectors are constructed in the model. The connector used to reflect the circumferential joint has three behaviors, namely, it can withstand shear, tension and pressure. The connector used to reflect the longitudinal joint has four behaviors, namely, it can withstand shear, tension, pressure and bending moment.

[0024] The simulation of continuous failure of shield tunnel is divided into two steps: Step 1: Set the initial boundary conditions and initial stress conditions for the model. Apply zero velocity boundary conditions on the sides and bottom of the Eulerian domain, and apply zero displacement boundary conditions on both sides of the tunnel.

[0025] Step 2: Remove the initial local failure segments. The local failure of the tunnel is simulated by removing the segments, which are called initial removal segments (IDSs). After the initial stress state is stabilized, the IDSs are removed to simulate the initial local failure of the tunnel.

[0026] In Model S EU_1 In the embodiment, a reinforcement unit is set, that is, in the third ring and the fourth ring adjacent to the local damage ring, the strength of the inner ring joint is strengthened so that it will not fail; at the same time, the strength of the inter-ring joint between the third ring and the fourth ring is strengthened so that it will not fail, such as Figure 3 Model S EU_2 In the embodiment, two reinforcement units are provided, namely, in the third ring and the fourth ring, the seventh ring and the eighth ring adjacent to the local damage ring, the strength of the inner ring joint is strengthened so that it will not fail; at the same time, the strength of the inter-ring joint between the third ring and the fourth ring, and between the seventh ring and the eighth ring is strengthened so that it will not fail. Figure 3 In both models, the tunnel depth is 4D and the local damage range is 2.5 rings.

[0027] The calculation results are as follows Figure 4As shown in the figure, in order to make the continuous damage range clearer, the deformation of the tunnel structure in the axial direction is enlarged by 3 times. The calculation results show that setting one or more reinforcement units around the local damage ring does not effectively prevent the occurrence of continuous damage. Figure 4 , it can be found that although the number of reinforcement units set in the two models is different, Figure 4 In a and b of the two models, the results show that the scope of continuous damage has developed to the 14th ring, that is, the scope of continuous damage in the two models is the same as the scope of continuous damage in the results of model S6. EU_1 and Model S EU_2 , but no reinforcement unit is set. According to the analysis of the continuous damage development process, after the continuous damage of the tunnel is triggered, the joints between the tunnel structures in the affected area are damaged first. EU_1 and S EU_2 The reinforcement units in the continuous damage influence range are all within the continuous damage influence range, which can only ensure that the joints in the reinforcement units will not be damaged, but can neither prevent the occurrence of continuous damage nor control the influence range of continuous damage. It can be seen that when the reinforcement unit is set within the continuous damage influence range, it is impossible to prevent the occurrence of continuous damage and control the scope of continuous damage.

[0028] Based on the previous calculation results, it can be seen that when the shield tunnel depth is 4D and the local damage range is 2.5 rings, the impact range of continuous damage is 14.5 rings. Figure 2 Therefore, in the model S EU_3 In the embodiment, the reinforcement unit is set at the edge of the continuous damage influence range, that is, the inner joint of the fourteenth ring and the fifteenth ring, and the inter-ring joint between them are strengthened, such as Figure 5 The calculation results are shown in a. Figure 5 As shown in b, the results show that after local damage occurs, continuous damage to the tunnel will still occur, and the range of continuous damage increases to 15.5 rings, which is larger than the calculation result of model S6. EU_3 In the example, the setting of the reinforcement unit did not reduce the influence range of the continuous damage, but increased the influence range of the continuous damage to 15.5 rings. EU_3 The results of model S6 and model S7 show that in model S6, after local damage occurs, the tension of the inter-ring joints in the adjacent tunnels of the local damage ring increases, among which the tension of the inter-ring joints between the 14th and 15th rings increases faster, and tensile damage occurs; after the inter-ring joints between the 14th and 15th rings fail, the tension in the inter-ring joints from the 15th ring to the farther range decreases, indicating that the failure of the inter-ring joints between the 14th and 15th rings has a certain protective effect on it. EU_3In the process, since the inter-ring joint between the fourteenth ring and the fifteenth ring will not fail during the continuous destruction process, the internal force between the fifteenth ring and the sixteenth ring continues to increase, and finally tensile failure occurs.

[0029] In order to further explore the control of the impact range of continuous damage, in the model S EU_3 Based on the Model S EU_4 The inner joints of the 13th, 16th and 17th rings were strengthened, and the inter-ring joints between the 13th and 14th rings, and the 15th to 17th rings were strengthened. Figure 6 As shown in a, the calculation results are as follows Figure 6 As shown in b, the results show that after local damage occurs, the impact of continuous damage is reduced to 12.5 rings. EU_4 In the above, although the reinforcement unit did not prevent the occurrence of continuous damage, it reduced the range of continuous damage. It is believed that when the reinforcement unit is set at the edge of the continuous damage influence range and the range of the reinforcement unit is increased to a certain extent, the reinforcement unit can play a role in controlling the continuous damage range.

[0030] It can be seen that in the above-mentioned embodiment, the shield tunnel continuous damage control strategy uses the continuous damage boundary 14.5 caused by the initial local damage as the position of the key ring, and then performs reinforcement operations with the critical length of the reinforcement unit 5 rings output by the shield tunnel continuous damage control strategy. That is, when the shield tunnel is buried at a depth of 4D and the local damage range is 2.5 rings, the continuous damage boundaries 14 and 15 rings are used as the positions of the key rings, and the reinforcement operations within and between the rings are performed with the critical lengths of the reinforcement units of the 5 rings 13, 14, 15, 16 and 17, so that the continuous damage range is reduced from 14.5 rings to 12.5 rings.

[0031] In order to further study the range of strengthening units required to control continuous failure, the model S EU_5 , the shield tunnel is buried at a depth of 3D, the local damage range is 2.5 ring segments, and the reinforcement unit is set at the edge of the continuous damage influence range. At the same time, it extends 1 ring on both sides of the tunnel axial direction, which can control the influence range of continuous damage and reduce the continuous damage range by 1 ring. Figure 7 The setup of Model S is shown in a. EU_6 , the shield tunnel is buried at a depth of 5D, the local damage range is 2.5 ring segments, and the reinforcement unit needs to be set at the edge of the continuous damage influence range. At the same time, it extends 7 rings along the tunnel axis away from the local damage ring and 1 ring toward the local damage ring. This can control the influence range of the continuous damage and reduce the continuous damage range by 1 ring. That is, Figure 7 As shown in b. Based on the above calculation results, it is believed that there are "key units" in shield tunnels that control the scope of continuous damage, that is, only when the key units are strengthened can the scope of continuous damage be changed. Taking the above-mentioned model cases as an example, when the tunnel depth is 3D and the local damage range is 2.5 rings, the key units are the eighth and ninth rings; when the tunnel depth is 4D and the local damage range is 2.5 rings, the key units are the fourteenth and fifteenth rings; when the tunnel depth is 5D and the local damage range is 2.5 rings, the key units are the twenty-second and twenty-third rings. If you want to ensure that the scope of continuous damage will not increase after strengthening the key rings, you should also extend the strengthening range along the tunnel axis away from the local damage ring. The range to be extended is related to the depth of the tunnel. Taking the above-mentioned partial model cases as an example, when the tunnel burial depth is 3D, strengthening the key units can control and reduce the scope of continuous damage; when the tunnel burial depth is 4D, the reinforcement ring range needs to be extended by 2 rings (i.e. the 16th and 17th rings) along the axial direction of the tunnel away from the local damage ring; and when the tunnel burial depth is 5D, the reinforcement ring range needs to be extended by 6 rings (i.e. the 24th to 29th rings) along the axial direction of the tunnel away from the local damage ring. At the same time, according to the cases in this section, on the basis of controlling the scope of continuous damage, in order to further reduce the scope of influence of continuous damage, the reinforcement range should be extended along the axial direction of the tunnel close to the local damage ring, and the reinforcement range should be the same as the scope of influence of continuous damage that can be reduced. In model S EU_5 and S EU_6 In the model S, the reinforcement ring strengthens the key unit, but does not extend further in the direction of local failure. EU_5 Compared with model S9 (the burial depth and initial local damage range are the same as model S EU_5 , but without reinforcement units), the impact range of continuous damage is reduced by 1 ring. Model S EU_6 and model S3 (the burial depth and initial local damage range are the same as those of model S EU_6 , but without strengthening units), the impact range of continuous damage is reduced by 1 ring; while in model S EU_4 In the model, the reinforcement range of the reinforcement ring continues to extend by 1 ring near the local failure direction, and compared with model S6, the influence range of continuous failure is reduced by 2 rings.

[0032] The continuous destruction control strategy for shield tunnels is the basis for controlling continuous destruction. It is mainly based on a large amount of known and accurate data to establish the correspondence between the buried depth of each shield tunnel and the outer diameter of the shield tunnel and the position of each key ring and the critical length of the reinforcement unit. The continuous destruction control strategy for shield tunnels can be in the form of a correspondence table, a fitting formula, or a neural network model. This application does not limit the form of the continuous destruction control strategy for shield tunnels. It mainly reflects the correspondence between the buried depth of each shield tunnel and the outer diameter of the shield tunnel and the position of each key ring and the critical length of the reinforcement unit.

[0033] In some embodiments, the method for obtaining the continuous destruction control strategy of the shield tunnel is: Collect relevant data of shield tunnels that have been continuously damaged in the past; the relevant data of shield tunnels that have been continuously damaged in the past include the buried depth of the shield tunnel, the outer diameter of the shield tunnel, the position of the key ring and the critical length of the reinforcement unit; By using numerical simulation methods, the continuous destruction of the shield tunnel is simulated to obtain relevant data of the shield tunnel that simulates continuous destruction; the relevant data of the shield tunnel that simulates continuous destruction include the buried depth of the shield tunnel, the outer diameter of the shield tunnel, the position of the key ring and the critical length of the reinforcement unit; A control strategy correspondence table is prepared based on the relevant data of shield tunnels that have been continuously damaged in history and the relevant data of shield tunnels that have been simulated to be continuously damaged; the control strategy correspondence table is the correspondence between the buried depth of each shield tunnel and the outer diameter of the shield tunnel and the position of each key ring and the critical length of the reinforcement unit; The control strategy correspondence table is used as the continuous destruction control strategy for shield tunnels.

[0034] In some embodiments, the method for obtaining the continuous destruction control strategy of the shield tunnel is: Collect relevant data of shield tunnels that have been continuously damaged in the past; the relevant data of shield tunnels that have been continuously damaged in the past include the buried depth of the shield tunnel, the outer diameter of the shield tunnel, the position of the key ring and the critical length of the reinforcement unit; By using numerical simulation methods, the continuous destruction of the shield tunnel is simulated to obtain relevant data of the shield tunnel that simulates continuous destruction; the relevant data of the shield tunnel that simulates continuous destruction include the buried depth of the shield tunnel, the outer diameter of the shield tunnel, the position of the key ring and the critical length of the reinforcement unit; According to the relevant data of shield tunnels that have been continuously damaged in history and the relevant data of shield tunnels that have been simulated to be continuously damaged, the control strategy fitting formula is obtained; the control strategy fitting formula is used to express the fitting relationship between the buried depth of each shield tunnel and the outer diameter of the shield tunnel and the position of each key ring and the critical length of the reinforcement unit; The control strategy fitting formula is used as the continuous destruction control strategy for shield tunnels.

[0035] The order of the control strategy fitting formula can be adjusted according to the requirements for control accuracy.

[0036] In some embodiments, the method for obtaining the continuous destruction control strategy of the shield tunnel is: Collect relevant data of shield tunnels that have been continuously damaged in the past; the relevant data of shield tunnels that have been continuously damaged in the past include the buried depth of the shield tunnel, the outer diameter of the shield tunnel, the position of the key ring and the critical length of the reinforcement unit; By using numerical simulation methods, the continuous destruction of the shield tunnel is simulated to obtain relevant data of the shield tunnel that simulates continuous destruction; the relevant data of the shield tunnel that simulates continuous destruction include the buried depth of the shield tunnel, the outer diameter of the shield tunnel, the position of the key ring and the critical length of the reinforcement unit; The relevant data of shield tunnels that have been continuously damaged in history and the relevant data of shield tunnels that have been simulated to be continuously damaged are used as training sets; Construct a control strategy model; use the buried depth of the shield tunnel and the outer diameter of the shield tunnel as the input of the control strategy model, and use the position of the key ring and the critical length of the reinforcement unit as the output of the control strategy model; Using the training set to train the control strategy model; Based on the trained control strategy model, the continuous destruction control strategy of the shield tunnel is output.

[0037] The control strategy model can be a neural network model or other machine learning model. The training end condition of the model can be a set number of iterations or reaching a preset loss function value. The hyperparameter setting of the model can also be adjusted according to the requirements for control accuracy.

[0038] S5: Along the extension direction of the shield tunnel, on both sides of the occurrence position, reinforcement units with critical lengths are set at the positions of the corresponding key rings to control the continuous destruction of the shield tunnel.

[0039] Due to the symmetry of the continuous destruction of the shield tunnel, after the initial local destruction occurs, it will extend to both sides of the occurrence position along the extension direction of the shield tunnel. Therefore, it is necessary to set reinforcement units with critical lengths at the positions of the corresponding key rings on both sides of the occurrence position to control the continuous destruction of the shield tunnel.

[0040] In some embodiments, reinforcement units with critical lengths are respectively arranged at the positions of key rings to control the continuous destruction of the shield tunnel, specifically: At the position of the key ring, reinforcing units are set both close to the initial local failure direction and away from the initial local failure direction; the sum of the ring numbers of the reinforcing units set is the critical length of the reinforcing units.

[0041] For example, when the shield tunnel is buried at a depth of 4D and the local damage range is 2.5 rings, the impact range of continuous damage is 14.5 rings, that is, the continuous damage boundary is between the 14th and 15th rings. EU_4 The inner joints of the 13th, 16th and 17th rings were strengthened, and the inter-ring joints between the 13th and 14th rings close to the initial local failure direction and between the 15th and 17th rings away from the initial local failure direction were strengthened.

[0042] In some embodiments, the reinforcement operation of the reinforcement unit includes an inter-ring reinforcement operation of the tunnel segment and an intra-ring reinforcement operation of the tunnel segment.

[0043] Performing both inter-ring reinforcement operations and intra-ring reinforcement operations simultaneously can significantly control the asymptotic damage of the shield tunnel, improve the overall performance and service life of the shield tunnel, and provide strong guarantees for the safe operation of the tunnel: Enhance the integrity of the tunnel: The inter-ring reinforcement operation strengthens the connection between the pipe rings, making the connection of the shield tunnel at the joints tighter and more stable. The intra-ring reinforcement operation enhances the strength and rigidity of the individual pipe segments. The combination of the two can significantly improve the integrity of the tunnel, making the tunnel more stable when facing external forces.

[0044] Improve the bearing capacity of the tunnel: The strengthening operations between and within the rings work together to enhance the bearing capacity of the tunnel. Even in the case of local damage, it can effectively prevent the expansion of the damage range and ensure the safety of the overall structure of the tunnel.

[0045] Prevent the expansion of continuous damage: Segment joints are the weak links in shield tunnels that are prone to damage. By simultaneously strengthening the inter-ring and intra-ring joints, the strength and durability of the joints can be significantly improved, thereby effectively preventing the expansion of continuous damage caused by joint damage.

[0046] Prolonging the service life of the tunnel: Strengthening operations can reduce the maintenance frequency and repair costs of the tunnel during use, thereby extending the service life of the tunnel. This is of great significance to improving the economic and social benefits of the tunnel.

[0047] In summary, in actual engineering, strengthening the connection between pipe rings can be achieved by setting tensioning steel beams between the rings. By applying pre-tension in the steel beam, the adjacent pipe rings are tightly pressed together, which can effectively strengthen the integrity of the tunnel and thus improve the bearing capacity of the tunnel. The trolley can be used as a temporary measure to strengthen the strength of the pipe ring. The trolley consists of a steel skeleton, a support arm, etc. It can move forward and backward along the tunnel axis in the track. Therefore, the trolley can timely reinforce the pipe ring that may be locally damaged or affected by local damage. However, since it occupies too much space, it cannot be used as a permanent reinforcement measure. During the operation of the tunnel, strengthening the strength of the pipe ring can be achieved by setting steel supports in the pipe ring. In comparison, the steel support occupies very little space and can be used permanently.

[0048] Through the exploration of the prevention and control measures for continuous damage of tunnels, this paper believes that the key to the study of continuous damage lies in determining the location of the key unit, that is, strengthening the key unit can change the scope of influence of continuous damage. In order to determine the prevention and control measures for continuous damage, the location of the key unit should be determined first, and then the scope of the strengthening unit should be determined. The inter-ring joints of the tunnel structure within the corresponding strengthening range should be strengthened, and the internal joints of the local damage rings should be strengthened to effectively protect the tunnel structure from the influence of continuous damage. In actual engineering, the connection between the tunnel rings can be strengthened by setting inter-ring tensioning steel beams between adjacent rings of the tunnel; at the same time, trolleys, internal steel supports and other methods can be used as temporary measures and permanent measures to strengthen the tunnel pipe rings.

[0049] The present application provides a method for controlling continuous destruction of a shield tunnel. According to the continuous destruction control strategy of the shield tunnel, the position of the key ring and the critical length of the reinforcement unit are determined, that is, reinforcement units with the critical length of the reinforcement unit are set at the position of the key ring to control the continuous destruction of the shield tunnel and improve the control effect.

[0050] On the other hand, the present application also provides a control system for continuous destruction of a shield tunnel, and implements a control method for continuous destruction of a shield tunnel as described above. The control system includes a destruction range threshold module, a current shield tunnel information acquisition module, and a continuous destruction control strategy output module: The damage range threshold module is used to obtain the buried depth and outer diameter of the current shield tunnel; the damage range threshold of the current shield tunnel is determined by the buried depth and outer diameter of the current shield tunnel; the damage range threshold is used to indicate the minimum number of damaged segment rings that cause continuous damage under the current buried depth and outer diameter; The current shield tunnel information acquisition module is used to obtain the location of the current initial local damage in the shield tunnel and the number of damaged segments; The continuous damage control strategy output module determines the position of the key ring and the critical length of the reinforcement unit based on the occurrence location and the continuous damage control strategy of the shield tunnel if the number of damaged segment rings exceeds the damage range threshold; the position of the key ring is the position where the reinforcement unit is set; the critical length of the reinforcement unit is the number of rings of the reinforcement unit.

[0051] It should be noted that the terms used in this application are only for describing specific embodiments, rather than limiting the scope of this application. As shown in the specification of this application, unless the context clearly indicates an exception, the words "one", "a", "a kind of" and / or "the" do not specifically refer to the singular, but may also include the plural. The terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method or device. In the absence of more restrictions, the elements defined by the sentence "include one..." do not exclude the presence of other identical elements in the process, method or device including the elements.

[0052] It should also be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. Unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", etc. should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0053] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the technical solutions of the embodiments of the present application.

Claims

1. A method for controlling continuous destruction of a shield tunnel, characterized in that: The steps include: Get the current shield tunnel's buried depth and outer diameter; Determine the damage range threshold of the current shield tunnel by the buried depth and outer diameter of the current shield tunnel; the damage range threshold is used to indicate the minimum number of damaged segment rings that cause continuous damage under the current buried depth and outer diameter; Obtain the location of the current initial local damage in the shield tunnel and the number of damaged segments; If the number of damaged segments exceeds the damage range threshold, based on the occurrence location and in accordance with the shield tunnel continuous damage control strategy, the location of the critical ring and the critical length of the reinforcement unit are determined; the location of the critical ring is the location where the reinforcement unit is set; and the critical length of the reinforcement unit is the number of rings of the reinforcement unit; Along the extension direction of the shield tunnel, on both sides of the occurrence position, reinforcement units with critical lengths are respectively arranged at the positions of corresponding key rings to control the continuous destruction of the shield tunnel.

2. A method for controlling continuous destruction of a shield tunnel according to claim 1, characterized in that: The method for obtaining the continuous destruction control strategy of the shield tunnel is: Collect relevant data of shield tunnels that have been continuously damaged in the past; the relevant data of shield tunnels that have been continuously damaged in the past include the buried depth of the shield tunnel, the outer diameter of the shield tunnel, the position of the key ring and the critical length of the reinforcement unit; By means of numerical simulation, continuous destruction of a shield tunnel is simulated to obtain relevant data of the shield tunnel in which continuous destruction is simulated; the relevant data of the shield tunnel in which continuous destruction is simulated include the buried depth of the shield tunnel, the outer diameter of the shield tunnel, the position of the key ring and the critical length of the reinforcement unit; According to the relevant data of the shield tunnels that have been continuously damaged in history and the relevant data of the shield tunnels that have been simulated to be continuously damaged, a control strategy correspondence table is prepared; The control strategy correspondence table is the correspondence between the buried depth of each shield tunnel and the outer diameter of the shield tunnel and the position of each key ring and the critical length of the reinforcement unit; The control strategy correspondence table is used as the shield tunnel continuous destruction control strategy.

3. A method for controlling continuous destruction of a shield tunnel according to claim 1, characterized in that: The method for obtaining the continuous destruction control strategy of the shield tunnel is: Collect relevant data of shield tunnels that have been continuously damaged in the past; the relevant data of shield tunnels that have been continuously damaged in the past include the buried depth of the shield tunnel, the outer diameter of the shield tunnel, the position of the key ring and the critical length of the reinforcement unit; By means of numerical simulation, continuous destruction of a shield tunnel is simulated to obtain relevant data of the shield tunnel in which continuous destruction is simulated; the relevant data of the shield tunnel in which continuous destruction is simulated include the buried depth of the shield tunnel, the outer diameter of the shield tunnel, the position of the key ring and the critical length of the reinforcement unit; According to the relevant data of the shield tunnels that have been continuously damaged in history and the relevant data of the shield tunnels that have been simulated to be continuously damaged, a control strategy fitting formula is obtained; the control strategy fitting formula is used to express the fitting relationship between the buried depth of each shield tunnel and the outer diameter of the shield tunnel and the position of each key ring and the critical length of the reinforcement unit; The control strategy fitting formula is used as the shield tunnel continuous destruction control strategy.

4. A method for controlling continuous destruction of a shield tunnel according to claim 1, characterized in that: The method for obtaining the continuous destruction control strategy of the shield tunnel is: Collect relevant data of shield tunnels that have been continuously damaged in the past; the relevant data of shield tunnels that have been continuously damaged in the past include the buried depth of the shield tunnel, the outer diameter of the shield tunnel, the position of the key ring and the critical length of the reinforcement unit; By means of numerical simulation, continuous destruction of a shield tunnel is simulated to obtain relevant data of the shield tunnel in which continuous destruction is simulated; the relevant data of the shield tunnel in which continuous destruction is simulated include the buried depth of the shield tunnel, the outer diameter of the shield tunnel, the position of the key ring and the critical length of the reinforcement unit; Using the relevant data of the shield tunnel that has been continuously destroyed in history and the relevant data of the shield tunnel that has been simulated to be continuously destroyed as a training set; Construct a control strategy model; use the buried depth of the shield tunnel and the outer diameter of the shield tunnel as the input of the control strategy model, and use the position of the key ring and the critical length of the reinforcement unit as the output of the control strategy model; Using the training set to train the control strategy model; Based on the trained control strategy model, the continuous destruction control strategy of the shield tunnel is output.

5. The method for controlling continuous destruction of a shield tunnel according to claim 1, characterized in that: The continuous damage boundary caused by the initial local damage is used as the position of the critical ring.

6. A method for controlling continuous destruction of a shield tunnel according to claim 5, characterized in that: Reinforcement units with critical lengths are set at the corresponding key ring positions to control the continuous destruction of the shield tunnel, specifically: At the position of the key ring, reinforcing units are arranged both close to the initial local failure direction and away from the initial local failure direction; the sum of the number of rings of the reinforcing units arranged is the critical length of the reinforcing units.

7. A method for controlling continuous destruction of a shield tunnel according to claim 1, characterized in that: The destruction range threshold of the current shield tunnel is determined by the buried depth and outer diameter of the current shield tunnel, specifically: By collecting historical data or using a numerical simulation method, a damage range threshold relationship is determined; the damage range threshold relationship is used to represent the corresponding relationship between the buried depth and outer diameter of each shield tunnel and the damage range threshold; According to the buried depth and outer diameter of the current shield tunnel, the damage range threshold relationship is found to determine the damage range threshold of the current shield tunnel.

8. A method for controlling continuous destruction of a shield tunnel according to claim 1, characterized in that: The reinforcement operation of the reinforcement unit includes the inter-ring reinforcement operation of the tunnel segment and the intra-ring reinforcement operation of the tunnel segment.

9. A control system for continuous destruction of a shield tunnel, executing a control method for continuous destruction of a shield tunnel as claimed in any one of claims 1 to 8, characterized in that: The control system includes a damage range threshold module, a current shield tunnel information acquisition module, and a continuous damage control strategy output module: A damage range threshold module is used to obtain the buried depth and outer diameter of the current shield tunnel; the damage range threshold of the current shield tunnel is determined by the buried depth and outer diameter of the current shield tunnel; the damage range threshold is used to represent the minimum number of damaged segment rings that cause continuous damage under the current buried depth and outer diameter; The current shield tunnel information acquisition module is used to obtain the location of the current initial local damage in the shield tunnel and the number of damaged segments; The continuous damage control strategy output module determines the position of the key ring and the critical length of the reinforcement unit based on the occurrence location and the continuous damage control strategy of the shield tunnel if the number of damaged segment rings exceeds the damage range threshold; the position of the key ring is the position where the reinforcement unit is set; and the critical length of the reinforcement unit is the number of rings of the reinforcement unit.

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