A tunneling state regulation method based on shield data

Abstract

The application discloses a kind of based on tunneling state regulation method of shield data, the method includes the following steps: collecting shield starts tunneling thrust growth section data and processing, obtains tunneling thrust, tunneling torque, resistance thrust and resistance torque;Contrast the last ring or test section shield resistance thrust recommended value, evaluate stratum stability and regulate soil bin pressure;When shield normally tunnels, real-time processing shield tunneling data, obtain shield tunneling state index real-time value of shield penetration index, cutterhead torque coefficient and screw machine torque coefficient, perfect shield tunneling database, and real-time analyze shield tunneling state, monitor and judge tool wear, construction risk such as mud cake, simultaneously adopt muck improvement real-time regulation shield tunneling state.

Description

Technical Field

[0001] This invention relates to the field of construction control technology for full-face tunnel boring machines, specifically to a method for controlling the tunneling status based on shield data. Background Technology

[0002] With the continuous development of underground and space engineering, the shield tunneling method has been widely applied to tunnel construction and is constantly being improved. The emergence of various shield tunneling methods, such as dual-mode shields, has increased the adaptability of shields to different geological formations. Tunneling parameters are important indicators for reflecting the tunneling status of the shield. However, there are complex correlations between these parameters. For example, an increase in shield thrust will lead to an increase in shield torque and tunneling speed; an increase in screw conveyor speed will lead to an increase in soil removal energy consumption and screw conveyor torque. Therefore, a single tunneling parameter is not representative of the shield tunneling status, and adjusting a single parameter cannot fully adjust the tunneling status. For instance, a decrease in shield torque may be due to improved soil improvement or a decrease in thrust. A reasonable method for evaluating the tunneling status of shields will provide a theoretical basis for refined control of shield tunneling and research on soil improvement, and is of great significance.

[0003] Based on existing research and engineering experience, we can divide the total thrust of a tunnel boring machine (TBM) into two parts: resisting thrust and tunneling thrust. Resisting thrust includes the frictional resistance between the shield and the soil, the active soil and water pressure of the soil, the frictional resistance between the shield tail and the tunnel segments, and the traction resistance of the subsequent trolley. Its magnitude is mainly affected by the TBM burial depth and soil properties. A greater burial depth or poorer soil stability results in greater active soil and water pressure and soil pressure on the shield sides, leading to greater frictional resistance between the TBM and the soil. Tunneling thrust, defined as the force exerted by the TBM on the tunnel face after removing the resisting thrust, is mainly related to the cutterhead cutter structure, soil strength, soil amendment status, and the set advance speed. Similarly, TBM torque can be divided into resisting torque and tunneling torque. Resisting torque includes the side frictional resistance of the cutterhead, the frictional torque between the soil in the soil chamber and the cutterhead panel, the frictional torque generated by the active soil pressure of the soil, and the mixing torque of the mixing rods. The tunneling torque is the shield torque excluding the resisting torque. The tunneling torque is mainly affected by the tunneling thrust, cutterhead structure, geological properties, and the condition of the excavated soil. Therefore, by eliminating the influence of unnecessary factors, the tunneling thrust and tunneling torque better reflect the shield's condition than the total thrust and total torque. Evaluating the shield's tunneling condition based on tunneling thrust, tunneling torque, resisting thrust, and resisting torque will also be of great significance. Summary of the Invention

[0004] The problem this invention aims to solve is to provide a method for controlling the tunneling status based on shield tunneling data, which enables refined control of the shield tunnel and prediction of tunneling risks. To solve the above technical problem, this invention adopts the following technical solution:

[0005] A method for controlling the tunneling status based on shield tunneling data includes the following steps:

[0006] S1. Collect and process the data of the shield tunneling thrust growth stage to obtain tunneling thrust, tunneling torque, resistance thrust and resistance torque;

[0007] The data on the shield tunneling thrust growth phase refers to the tunneling data during the period when the total thrust of each ring of the shield tunneling begins to increase. The collected data includes the total shield thrust, total torque, and time. The processing includes plotting a curve of shield torque changing with total thrust. The resisting thrust is the portion of thrust that does not contribute to the shield torque, the resisting torque is the portion of torque that does not increase with the shield thrust, the tunneling thrust is the thrust that causes the shield torque to increase, and the tunneling torque is the torque generated due to the increase in shield thrust.

[0008] S2. Compare the resistance thrust of the previous ring or its suggested value to evaluate the formation stability and adjust the soil chamber pressure;

[0009] S3. During normal tunneling, the tunneling data is processed in real time to obtain real-time values ​​of tunneling status indicators such as tunnel penetration index, cutterhead torque coefficient and screw conveyor torque coefficient, thereby improving the tunneling database.

[0010] The normal tunneling of the shield is the tunneling state in which the thrust no longer increases and stabilizes within a certain range after the shield starts tunneling. The shield penetration index is the ratio of tunneling thrust to tunneling speed. The cutterhead torque coefficient is the ratio of tunneling torque to tunneling thrust. The screw conveyor torque coefficient is the ratio of screw conveyor torque to rotational speed.

[0011] S4. Real-time analysis of the tunnel boring machine's progress status to assess construction risks such as cutter wear and mud cake formation;

[0012] The strength of the strata and the cutting ability of the cutterhead to the current strata are judged by the magnitude of the shield penetration index. The strength or cohesion of the current tunneling strata is judged by the magnitude of the cutterhead torque coefficient. The effectiveness of the shield muck improvement is judged by the magnitude of the screw conveyor torque coefficient and the muck condition at the shield muck outlet. The real-time values ​​of the shield penetration index, cutterhead torque coefficient and screw conveyor torque coefficient are compared with the previous step or the corresponding recommended values ​​to analyze the changes in strata properties and muck improvement status in real time, so as to evaluate the risks such as current cutter wear or mud cake formation.

[0013] S5. Real-time control of shield tunneling status is achieved by using slag soil improvement.

[0014] Adjust the parameters of the spoil and soil improvement according to the risks to ensure that the tunnel boring machine is in a reasonable state.

[0015] S6. Repeat steps S1-S5 until the tunnel boring machine is finished.

[0016] Preferably, the recommended value of shield resistance thrust in step S2 is a representative recommended value of the corresponding stratum obtained during the tunneling of the shield test section, or a recommended value obtained based on engineering experience, theoretical analysis and other methods.

[0017] Preferably, the evaluation of formation stability in step S2 is based on the difference between the resistance to thrust of the ring or the ratio of resistance to thrust to burial depth and the corresponding recommended value. When the resistance to thrust of the ring or the ratio of resistance to thrust to burial depth is greater than the corresponding recommended value, it indicates that the formation stability is poor and requires greater support force; otherwise, the opposite is true.

[0018] Preferably, step S3 involves processing the shield tunneling data in real time by subtracting the resistance thrust from the real-time total thrust of the shield to obtain the real-time tunneling thrust, subtracting the resistance torque from the real-time total torque of the shield to obtain the real-time tunneling torque, and collecting the torque and speed of the screw conveyor.

[0019] Preferably, the improved shield tunneling database mentioned in step S3 is a database that integrates shield tunneling data from various projects. The data recorded in the database includes: shield parameters, geological parameters, and shield tunneling status. The shield machine parameters include shield machine model, structure, size, weight, segment width, etc. The geological parameters include geological type and parameters, water abundance, tunnel depth, etc. The shield tunneling status includes shield penetration index, cutterhead torque coefficient, screw conveyor torque coefficient, shield tunneling data, and muck slump. The database can statistically analyze representative values ​​for each shield tunneling status, such as the mean value after removing outliers. When a shield tunnels in the corresponding geological strata with the same shield parameters, the representative status of shield tunneling can be queried through the database, and each indicator can be used as a suggested value for that shield tunneling status.

[0020] Preferably, the real-time analysis of the tunnel boring machine's (TBM) tunneling status in step S4 involves comparing the relative magnitudes of the TBM tunneling status indicators with the recommended values ​​to determine the magnitude of each risk. For example, if the TBM penetration index is greater than 10% of the recommended value, it indicates that the stratum strength has increased; if the cutterhead torque coefficient is increased, it indicates that the stratum's machinability has decreased; and if the screw conveyor torque coefficient is increased, it indicates that the TBM is having difficulty removing slag.

[0021] As a preferred option, step S4 involves judging construction risks such as cutter wear and mud cake formation. When the shield penetration index is greater than the recommended threshold, it indicates that the stratum strength is high and the cutter has a greater risk of wear. When the cutterhead torque coefficient is greater than the recommended threshold and the stratum being traversed is clay, it indicates that the stratum adhesion is high and the shield has a greater risk of mud cake formation.

[0022] Preferably, step S5 involves using soil amendment to control the shield tunneling status in real time. When the cutterhead torque coefficient is greater than the recommended value, the soil amendment effect should be increased to restore the cutterhead torque coefficient to near the recommended value. When the shield penetration index is large, the cutterhead wear should be checked. If the cutterhead wear is small, the cutterhead blades can be lubricated by adding foaming agent through soil amendment, thereby increasing its cutting and crushing effect and reducing the shield penetration index. When the screw conveyor torque coefficient is large, it indicates that there is a lot of soil accumulation in the screw conveyor or the soil amendment effect is not good. When the screw conveyor torque coefficient is still large after moderate slag removal, the soil amendment effect should be increased to reduce the screw conveyor torque coefficient to within the recommended value range.

[0023] Preferably, the type, mode, and size of the tunnel boring machine are not limited, and the method is applicable to various tunneling machines, not limited to tunnel boring machines. Attached Figure Description

[0024] Figure 1 A flowchart of a tunneling status control method based on shield tunneling data provided by the present invention;

[0025] Figure 2 This is a diagram showing the processing parameters of the tunneling parameters during the initial thrust increase stage of the shield tunneling according to the present invention.

[0026] Figure 3 Example diagram of the penetration index variation for a single-ring shield tunnel;

[0027] Figure 4 Example diagram showing the variation of torque coefficient of a single-ring shield cutterhead;

[0028] Figure 5 This is an example diagram showing the variation of the torque coefficient of a single-ring shield tunneling machine. Detailed Implementation

[0029] The technical solution of the present invention will be clearly and completely described below through specific embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] A method for controlling the tunneling status based on shield tunneling data includes the following steps:

[0031] S1. Collect and process the data of the shield tunneling thrust growth stage to obtain tunneling thrust, tunneling torque, resistance thrust and resistance torque;

[0032] The data on the shield tunneling thrust increase phase refers to the tunneling data during the period when the total thrust of the shield tunneling increases. The collected data includes the total thrust, total torque, and time. The processing includes plotting a curve of the shield torque versus the total thrust (e.g., ...). Figure 2 The resisting thrust is the portion of the thrust that does not contribute to the shield torque, the resisting torque is the portion of the torque that does not increase with the shield thrust, the tunneling thrust is the thrust that causes the shield torque to increase, and the tunneling torque is the torque generated due to the increase of the shield thrust.

[0033] S2. Compare the resistance thrust of the previous ring or its suggested value to evaluate the formation stability and adjust the soil chamber pressure;

[0034] S3. During normal tunneling, the tunneling data is processed in real time to obtain real-time values ​​of tunneling status indicators such as tunnel penetration index, cutterhead torque coefficient and screw conveyor torque coefficient, thereby improving the tunneling database.

[0035] The normal tunneling of the shield is the tunneling state in which the thrust no longer increases and stabilizes within a certain range after the shield starts tunneling. The shield penetration index is the ratio of tunneling thrust to tunneling speed. The cutterhead torque coefficient is the ratio of tunneling torque to tunneling thrust. The screw conveyor torque coefficient is the ratio of screw conveyor torque to rotational speed.

[0036] S4. Real-time analysis of the tunnel boring machine's progress status to assess construction risks such as cutter wear and mud cake formation;

[0037] The strength of the strata and the cutting ability of the cutterhead to the current strata are judged by the magnitude of the shield penetration index. The strength or cohesion of the current tunneling strata is judged by the magnitude of the cutterhead torque coefficient. The effectiveness of the shield muck improvement is judged by the magnitude of the screw conveyor torque coefficient and the muck condition at the shield muck outlet. The real-time values ​​of the shield penetration index, cutterhead torque coefficient and screw conveyor torque coefficient are compared with the previous step or the corresponding recommended values ​​to analyze the changes in strata properties and muck improvement status in real time, so as to evaluate the risks such as current cutter wear or mud cake formation.

[0038] S5. Real-time control of shield tunneling status is achieved by using slag soil improvement.

[0039] Adjust the parameters of the spoil and soil improvement according to the risks to ensure that the tunnel boring machine is in a reasonable state.

[0040] S6. Repeat steps S1-S5 until the tunnel boring machine is finished.

[0041] Table 1. Different Shield Tunneling States and Geological Conditions

[0042] Crossing the strata Burial depth Resisting Torque Resisting thrust Cutter head torque coefficient Stratigraphic Penetration Index screw compressor torque coefficient <2-3>Silty medium-coarse sand 18 702.401 13444.50 0.412 101.083 2.601 <6> Completely weathered argillaceous siltstone 22 283.561 10880.75 0.302 107.034 2.845 <7-1> Strongly weathered gravelly coarse sandstone 23 817.478 9220.967 0.378 151.186 3.020 <8-1> Moderately weathered gravelly coarse sandstone 25 369.227 10139.07 0.478 171.379 3.133 <8-1> Moderately weathered gravelly coarse sandstone, <9-1> Slightly weathered gravelly coarse sandstone 26 297.081 11265.33 0.419 214.656 3.590 <9-1> Slightly weathered gravelly coarse sandstone 26 493.871 10658.07 0.450 268.255 3.460 <f-4>moderately weathered granitic fractured rock 25 641.364 12828.38 0.582 78.143 4.175

[0043] By statistically analyzing the tunneling parameters of each shield tunnel project when traversing corresponding strata, representative values ​​of the tunneling state parameters for each stratum are obtained, as shown in Table 1. When the shield tunneling begins, the shield tunneling parameters are acquired in real time, and a graph showing the change of shield torque with total thrust during the shield thrust growth stage is plotted using a computer. An example is shown below. Figure 2As shown, the shield's resistance thrust and resistance torque are obtained. Since the single-ring tunneling distance is relatively short, the single-ring resistance thrust and resistance torque are considered to remain constant during shield tunneling, while the tunneling thrust and tunneling torque change continuously as the shield tunnels advance.

[0044] Based on the slag discharge and geological survey data, the stratigraphic type is determined to be moderately weathered gravelly coarse sandstone. According to Table 1, the recommended values ​​for the cutterhead torque coefficient, stratigraphic penetration index, and screw conveyor torque coefficient are 0.478, 171.379, and 3.133, respectively. During normal tunnel boring machine (TBM) excavation, the total thrust and torque of the TBM are acquired in real time. The TBM penetration index, cutterhead torque coefficient, and screw conveyor torque coefficient are calculated based on the resisting thrust and torque, and compared with the corresponding recommended values. If the TBM penetration index exceeds the recommended value by 10% at a certain moment, it indicates an increase in the strength of the strata the TBM is traversing, leading to a decrease in the cutterhead's penetration capability. In this case, the TBM excavation speed should be appropriately reduced, and the soil improvement effect should be increased to reduce the risk of cutterhead wear; otherwise, the opposite applies. When the cutterhead torque coefficient exceeds the recommended value by 10%, it indicates an increase in the friction coefficient between the strata and the cutterhead. In this case, the TBM excavation speed should be appropriately reduced, and the soil improvement effect should be increased to reduce the risk of cutterhead wear; otherwise, the opposite applies. When the screw conveyor torque coefficient exceeds the recommended value by 10%, it indicates that the soil improvement effect is poor due to changes in strata or soil moisture content. The type and state of the soil at the muck outlet should be checked, and it should be considered whether the soil conditioner needs to be replaced. Simultaneously, the amount of soil conditioner should be increased to enhance the soil improvement effect; otherwise, the opposite applies. Warnings regarding changes in the above parameters are implemented through corresponding software and terminal devices. For example... Figure 3-5 As shown, during shield tunneling, the torque coefficient of the cutterhead and the torque coefficient of the screw conveyor both fluctuated around the recommended values, generally less than 10% of the recommended values. However, the shield penetration index was larger at the beginning and end of tunneling, exceeding the recommended value by 10%, indicating that the stratum strength was greater. At this time, the effect of soil improvement was increased and the flushing and water injection on the cutterhead were strengthened to reduce cutter wear.

[0045] The above embodiments are merely illustrative examples to clearly illustrate the present invention and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all embodiments here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A tunneling state regulation method based on shield data, characterized in that, It comprises the following steps: S1, collecting shield starting excavation thrust growth section data for processing to obtain the thrust, torque, resistance thrust and resistance torque; The shield starting excavation thrust growth section data is the excavation data in the period of the total thrust increase of the shield starting excavation, the collected data includes the total thrust, total torque and time; the processing includes drawing a curve of the shield torque with the total thrust, the resistance thrust is the part of the thrust that does not contribute to the shield torque, the resistance torque is the part of the torque that does not increase with the shield thrust, the excavation thrust is the thrust that causes the shield torque to increase, and the excavation torque is the torque generated due to the increase of the shield thrust; S2, comparing the resistance thrust of the previous ring or the recommended value, evaluating the stability of the stratum and regulating the soil chamber pressure; S3, when the shield is normally excavating, the shield excavation data is processed in real time to obtain the real-time values of the shield penetration index, the cutter head torque coefficient and the screw machine torque coefficient, and the shield excavation database is improved; The shield is normally excavating after the thrust no longer increases and is stable in a certain range of the excavation state, the shield penetration index is the ratio of the excavation thrust to the excavation speed, the cutter head torque coefficient is the ratio of the excavation torque to the excavation thrust, and the screw machine torque coefficient is the ratio of the screw machine torque to the speed; S4, real-time analysis of the shield excavation state to determine the cutter wear and the risk of mud cake construction; According to the size of the shield penetration index, the strength of the stratum and the cutting ability of the cutter to the current stratum are determined, according to the size of the cutter head torque coefficient, the strength of the current excavation stratum or the adhesion property is determined, and according to the size of the screw machine torque coefficient and the state of the slag soil of the shield discharge port, the improvement effect of the shield slag soil is determined; the real-time values of the shield penetration index, the cutter head torque coefficient and the screw machine torque coefficient are compared with the previous ring or the corresponding parameter recommended value, the changes of the stratum property and the slag soil improvement state are analyzed in real time, and the current cutter wear or mud cake risk is evaluated; S5, real-time regulation of the shield excavation state by using the slag soil improvement; According to the risk, the slag soil improvement parameters are reasonably regulated to make the shield excavation in a reasonable state; S6, repeating steps S1-S5 until the shield excavation is completed.

2. The tunneling state regulation method based on shield data according to claim 1, characterized in that, The shield resistance thrust recommended value in step S2 is a representative recommended value of the corresponding stratum obtained during the excavation process of the shield test section or a recommended value obtained according to engineering experience and theoretical analysis.

3. The tunneling state regulation method based on shield data according to claim 1, characterized in that, The evaluation of the stability of the stratum in step S2 is the difference between the resistance thrust of the current ring or the ratio of the resistance thrust to the buried depth and the corresponding recommended value; when the resistance thrust of the current ring or the ratio of the resistance thrust to the buried depth is greater than the corresponding recommended value, it indicates that the stability of the stratum is poor, and a larger supporting force is needed, otherwise, it is the opposite.

4. The tunneling state regulation method based on shield data according to claim 1, characterized in that, The real-time processing of the shield excavation data in step S3 is to subtract the resistance thrust from the real-time total thrust of the shield to obtain the real-time excavation thrust, subtract the resistance torque from the real-time total torque of the shield to obtain the real-time excavation torque, and collect the screw conveyor torque and speed.

5. The tunneling state regulation method based on shield data according to claim 1, characterized in that, The improved shield tunneling database of step S3 is a database for comprehensively recording shield tunneling data of various projects, and the recorded data includes shield parameters, stratum parameters and shield tunneling states; the shield parameters include shield model, structure, size, weight, segment width, the stratum parameters include stratum type and parameters, water enrichment condition, tunnel depth, and the shield tunneling states include shield penetration index, cutter head torque coefficient, screw machine torque coefficient, shield tunneling data and spoil slump; the database can calculate representative values of various shield tunneling states, and when the shield is tunneling in the corresponding stratum with the same shield parameters, the representative shield tunneling states are queried through the database, and various indexes are used as recommended values of the shield tunneling states.

6. The tunneling state regulation method based on shield data according to claim 1, characterized in that, The real-time analysis of shield tunneling states of step S4 is to compare the relative size of the shield tunneling state indexes and the recommended values to determine the size of each risk.

7. The tunneling state regulation method based on shield data according to claim 1, characterized in that, The cutter wear and mud cake construction risk of step S4 is determined when the shield penetration index is greater than the threshold value of the recommended value, which indicates that the stratum strength is relatively large, and the cutter has a large wear risk; when the cutter head torque coefficient is greater than the threshold value of the recommended value and the stratum to be penetrated is clay stratum, it indicates that the stratum adhesion is relatively large, and the shield has a large mud cake risk.

8. The tunneling state regulation method based on shield data according to claim 1, characterized in that, The spoil improvement for real-time regulation of shield tunneling states of step S5 is that when the cutter head torque coefficient is greater than the recommended value, the spoil improvement effect should be increased to restore the cutter head torque coefficient to the vicinity of the recommended value; when the shield penetration index is large, the cutter head wear condition should be checked, if the cutter head wear is small, the cutter head is lubricated through spoil improvement to increase the cutting and crushing effect, so as to reduce the shield penetration index; when the screw machine torque coefficient is large, it indicates that there is more spoil accumulation in the screw machine or the spoil improvement effect is poor; when the screw machine torque coefficient is still large after the spoil is appropriately discharged, the spoil improvement effect should be increased to reduce the screw machine torque coefficient to the recommended value range.

9. The tunneling state regulation method based on shield data according to claim 1, characterized in that, The type, mode and size of the shield are not limited, and the method is suitable for various tunneling machines and is not limited to the shield.

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