Stratum disturbance real-time early warning method, tunnel early warning method and system

Abstract

The invention relates to a stratum disturbance real-time early warning method and system and a tunnel early warning method and system. The stratum disturbance real-time early warning method comprises the following steps that the shield over-excavation volume is obtained in real time; calculating a ground surface settlement prediction value at the center line of the tunnel in real time based on the shield over-excavation volume and the settling tank width coefficient; obtaining a correction coefficient used for correcting deviation caused by the shield over-excavation volume and the geological parameter discreteness; calculating a ground surface settlement prediction value corresponding to the ground surface monitoring point in real time based on the horizontal distance from the ground surface monitoring point to the tunnel center line, the correction coefficient, the ground surface settlement prediction value at the tunnel center line and the settling tank width coefficient; and comparing the ground surface settlement predicted value corresponding to the ground surface monitoring point with an early warning threshold value in real time, and sending an early warning signal before the stratum sinks according to a comparison result until the construction operation is completed. According to the stratum disturbance real-time early warning method and system and the tunnel early warning method and system, the problem that real-time early warning cannot be conducted on ground surface settlement through an existing ground surface settlement analysis method is solved.

Description

Technical Field

[0001] This invention relates to the field of tunnel construction technology, and in particular to a real-time early warning method for ground disturbance, a tunnel early warning method and system. Background Technology

[0002] Existing surface settlement analyses for shield tunnels primarily employ two approaches: numerical simulation and extrapolation analysis based on surface monitoring data. Numerical simulation, tailored to the specific tunnel dimensions, depth, and geological conditions, selects an approximate geotechnical constitutive model and calculates the degree of surface disturbance by simulating the tunnel excavation process. Extrapolation analysis based on surface monitoring data analyzes the geometric characteristics of surface settlement deformation based on extensive post-construction settlement monitoring data. Combined with the tunnel's geological and excavation conditions, various empirical formulas for settlement calculation are derived, the most famous being the PECK formula.

[0003] These two methods of surface subsidence analysis cannot achieve real-time prediction of subsidence. As a result, when the surface subsidence data reaches the warning threshold, the strata have already formed an irreversible subsidence trend, and it is difficult to control the development of subsidence in time even after emergency measures are taken. Summary of the Invention

[0004] The main objective of this invention is to propose a real-time early warning method for ground disturbance, a tunnel early warning method, and a system, aiming to solve the problem that existing surface subsidence analysis methods cannot provide real-time early warning of surface subsidence.

[0005] To achieve the above objectives, this invention proposes a real-time early warning method for ground disturbance, comprising the following steps: real-time acquisition of shield tunnel over-excavation volume; real-time calculation of the predicted surface settlement value at the tunnel centerline based on the shield tunnel over-excavation volume and the settlement trough width coefficient; acquisition of correction coefficients to correct deviations caused by the shield tunnel over-excavation volume and the dispersion of geological parameters; real-time calculation of the predicted surface settlement value corresponding to the surface monitoring point based on the horizontal distance from the surface monitoring point to the tunnel centerline, the correction coefficient, the predicted surface settlement value at the tunnel centerline, and the settlement trough width coefficient; real-time comparison of the predicted surface settlement value corresponding to the surface monitoring point with an early warning threshold, and issuance of an early warning signal before ground subsidence based on the comparison results, until the construction work is completed.

[0006] According to some embodiments of the present invention, the real-time acquisition of shield tunnel over-excavation volume includes:

[0007] Obtain the tunneling distance of the tunnel boring machine;

[0008] The design excavation volume of the shield cutterhead is calculated based on the radius of the shield cutterhead and the tunneling distance.

[0009] Obtain the grouting volume and grouting loss coefficient of the tunnel boring machine;

[0010] Obtain the corrected slag volume;

[0011] The over-excavation volume of the shield tunnel is calculated based on the corrected slag discharge volume, the designed excavation volume, the grouting volume, the grouting loss coefficient, and the tunneling distance.

[0012] According to some embodiments of the present invention, obtaining the corrected slag volume includes:

[0013] Obtain the actual over-excavation volume;

[0014] The first slag discharge volume is calculated based on the designed excavation volume and the actual over-excavation volume.

[0015] Obtain the volume of slag discharged from the virtual square;

[0016] To obtain the volume of slurry in the slag;

[0017] Obtain the formation looseness coefficient;

[0018] The second slag discharge volume is calculated based on the virtual slag discharge volume, the slurry volume, and the formation loosening coefficient.

[0019] The ratio of slag discharge difference is calculated based on the first slag discharge volume and the second slag discharge volume.

[0020] If the slag discharge difference ratio is less than the first preset threshold, then the first slag discharge volume is used as the corrected slag discharge volume;

[0021] If the slag discharge difference ratio is greater than the first preset threshold, the actual over-excavation volume and the virtual slag discharge volume are re-acquired until the slag discharge difference ratio is less than the first preset threshold.

[0022] According to some embodiments of the present invention, obtaining the virtual slag discharge volume includes:

[0023] Obtain the average weight of the construction waste within a preset time period;

[0024] Obtain the average volume of construction waste within a preset time period;

[0025] The dynamic bulk density of the waste soil is calculated based on the average weight and average volume of the waste soil.

[0026] Get the current weight of the construction waste;

[0027] The virtual slag discharge volume is calculated based on the current weight and the dynamic bulk density.

[0028] According to some embodiments of the present invention, obtaining the slurry volume in the slag soil includes:

[0029] Obtain the filling coefficient and mud density;

[0030] The discharge volume is calculated based on the designed excavation volume, the filling coefficient, and the mud density.

[0031] The grout-containing volume is calculated based on the grouting volume and the grout discharge volume.

[0032] This invention also provides a tunnel early warning method, comprising the following steps: dividing the entire tunnel into multiple segments and setting up surface monitoring points for each segment; based on the correction coefficient corresponding to the current segment, using the real-time early warning method for ground disturbance as described in any one of claims 1 to 5, obtaining the predicted surface subsidence value corresponding to the surface monitoring point of the current segment in real time; comparing the predicted surface subsidence value with the early warning threshold in real time, and issuing an early warning signal before ground subsidence based on the comparison result, until the current segment of the tunnel is completed; obtaining the corresponding correction coefficient for the next segment of the tunnel, and using the above method to provide real-time early warning for ground disturbance, until the entire tunnel is completed.

[0033] According to some embodiments of the present invention, obtaining the corresponding correction coefficient for the next tunnel segment includes:

[0034] After the tunnel section is completed and a preset time has elapsed, the measured values ​​of surface settlement corresponding to the surface monitoring points of the tunnel section are obtained, and the settlement deviation value and settlement difference ratio are calculated based on the measured values ​​of surface settlement and the predicted values ​​of surface settlement.

[0035] If the settlement difference ratio is less than the second preset threshold, the current correction coefficient will be used as the corresponding correction coefficient for calculating the next tunnel segment.

[0036] If the settlement difference ratio is greater than the second preset threshold, the settlement deviation value, the corrected slag volume and the grouting volume are input into the machine learning model, which outputs the iterative correction coefficient, and the iterative correction coefficient is used as the corresponding correction coefficient for calculating the next tunnel section.

[0037] According to some embodiments of the present invention, after obtaining the predicted surface settlement value corresponding to the surface monitoring point of this tunnel section, the method further includes:

[0038] The warning level is determined based on the predicted surface subsidence value and the warning threshold, and the adjustment strategies for grouting volume, tunnel boring machine thrust, tunnel boring machine torque and tunneling speed are determined based on the warning level.

[0039] According to some embodiments of the present invention, the step of determining the early warning level based on the predicted surface subsidence value and the early warning threshold, and determining the adjustment strategy for grouting volume, tunnel boring machine thrust, tunnel boring machine torque, and tunneling speed based on the early warning level, includes:

[0040] When the predicted surface settlement value is less than 0.8 times the warning threshold, the warning level is determined to be normal, and the initial grouting volume, initial shield machine thrust, initial shield machine torque and initial tunneling speed are maintained.

[0041] When the predicted value of surface subsidence is less than the warning threshold but greater than 0.8 times the warning threshold, the warning level is determined to be warning level, and the grouting volume is adjusted to the first preset volume, the shield machine thrust is adjusted to the first preset thrust, the shield machine torque is adjusted to the first preset torque, and the initial tunneling speed is maintained.

[0042] When the predicted value of surface subsidence is greater than the warning threshold, the warning level is determined to be emergency level, and the grouting volume is adjusted to the second preset volume, the shield machine thrust is adjusted to the second preset thrust, the shield machine torque is adjusted to the second preset torque, and the tunneling speed is adjusted to the preset speed.

[0043] Among them, the initial grouting volume < the first preset volume < the second preset volume, the initial shield machine thrust > the first preset thrust > the second preset thrust, the initial shield machine torque > the first preset torque > the second preset torque, and the initial tunneling speed > the preset speed.

[0044] Furthermore, the present invention also provides a settlement early warning system for tunnel construction, based on the real-time early warning method for ground disturbance as described in any of the above-mentioned methods. The settlement early warning system includes a control center, a tunnel boring machine (TBM), a muon density imaging device, a ground-penetrating radar, a three-dimensional laser scanner, a conveyor belt, and multiple settlement monitoring devices corresponding to various surface monitoring points. The muon density imaging device, the ground-penetrating radar, and the three-dimensional laser scanner are all mounted on the TBM. The conveyor belt is located on the discharge side of the TBM's slag outlet and is within the detection range of the three-dimensional laser scanner. The grouting metering device of the TBM, the muon density imaging device, the ground-penetrating radar, the three-dimensional laser scanner, the conveyor belt, and the multiple settlement monitoring devices are all electrically connected to the control center.

[0045] The present invention has at least the following beneficial effects:

[0046] In this invention, the over-excavation volume of the shield tunnel is first acquired in real time. Then, based on the over-excavation volume and the settlement trough width coefficient, the predicted surface settlement value at the tunnel centerline is calculated in real time. Next, a correction coefficient is obtained to correct the deviation caused by the over-excavation volume and the dispersion of geological parameters. Based on the horizontal distance from the surface monitoring point to the tunnel centerline, the correction coefficient, the predicted surface settlement value at the tunnel centerline, and the settlement trough width coefficient, the predicted surface settlement value corresponding to the surface monitoring point is calculated in real time. Finally, the predicted surface settlement value corresponding to the surface monitoring point is compared with the warning threshold in real time, and a warning signal is issued before the stratum subsides based on the comparison results, until the construction operation is completed. In this invention, the shield tunneling over-excavation volume is the ground over-excavation amount. The predicted ground settlement value at the tunnel centerline is calculated using the shield tunneling over-excavation volume and the settlement trough width coefficient. Then, the theoretical predicted ground settlement value for this section of the tunnel can be calculated using the horizontal distance and the predicted ground settlement value at the tunnel centerline. The deviation caused by the shield tunneling over-excavation volume and the dispersion of geological parameters is corrected by a correction coefficient, reducing the deviation between the final predicted ground settlement value and the actual settlement value. This allows for accurate issuance of early warning signals after comparing the predicted ground settlement value with the early warning threshold. Furthermore, real-time early warning of ground settlement is achieved by acquiring the predicted ground settlement value in real time and comparing it with the early warning threshold in real time. Attached Figure Description

[0047] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0048] Figure 1 This is a flowchart illustrating the first embodiment of the real-time early warning method for formation disturbance of the present invention;

[0049] Figure 2 This is a flowchart illustrating the second embodiment of the real-time early warning method for formation disturbance of the present invention;

[0050] Figure 3 This is a flowchart illustrating the third embodiment of the real-time early warning method for formation disturbance of the present invention;

[0051] Figure 4 This is a flowchart illustrating the fourth embodiment of the real-time early warning method for formation disturbance of the present invention;

[0052] Figure 5 This is a flowchart illustrating the fifth embodiment of the real-time early warning method for formation disturbance of the present invention;

[0053] Figure 6This is a flowchart illustrating the first embodiment of the tunnel early warning method of the present invention;

[0054] Figure 7 This is a flowchart illustrating the second embodiment of the tunnel early warning method of the present invention;

[0055] Figure 8 This is a flowchart illustrating the third embodiment of the tunnel early warning method of the present invention;

[0056] Figure 9 This is a flowchart illustrating the fourth embodiment of the tunnel early warning method of the present invention;

[0057] Figure 10 This is a schematic diagram of a settlement early warning system for tunnel construction provided in an embodiment of the present invention;

[0058] Figure 11 for Figure 10 A cross-sectional view of the interaction between ground-penetrating radar and tunnel boring machine;

[0059] Figure 12 for Figure 10 A schematic diagram of the detection range of the muon density imaging device in the image;

[0060] Figure 13 A schematic diagram illustrating the use of a 3D laser scanner and a conveyor belt to detect the volume and weight of construction waste.

[0061] Explanation of reference numerals in the attached figures:

[0062] 100-Settlement early warning system; 1-Shield tunneling machine; 2-Müller density imaging device; 3-Ground radar; 4-3D laser scanner; 5-Conveyor belt conveyor; 200-Stratum; 300-Slag and soil. Detailed Implementation

[0063] The technical solutions in the embodiments of the present invention will be clearly and completely described below. 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.

[0064] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0065] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the meaning of "and / or" throughout the text includes three parallel solutions; for example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0066] This invention provides a real-time early warning method for ground disturbance, a tunnel early warning method, and a settlement early warning system. Figures 1 to 13 This invention provides a specific embodiment of a real-time early warning method for ground disturbance, a tunnel early warning method, and a settlement early warning system.

[0067] like Figures 10 to 13 As shown, this embodiment of the invention provides a settlement early warning system 100 for tunnel construction, including a control center, a tunnel boring machine (TBM) 1, a muon density imaging device 2, a ground-penetrating radar 3, a three-dimensional laser scanner 4, a conveyor belt 5, and multiple settlement monitoring devices corresponding to various surface monitoring points. The muon density imaging device 2, the ground-penetrating radar 3, and the three-dimensional laser scanner 4 are all mounted on the TBM 1. The conveyor belt 5 is located on the discharge side of the TBM 1's slag outlet and is within the detection range of the three-dimensional laser scanner 4. The grouting metering device of the TBM 1, the muon density imaging device 2, the ground-penetrating radar 3, the three-dimensional laser scanner 4, the conveyor belt 5, and the multiple settlement monitoring devices are all electrically connected to the control center.

[0068] Those skilled in the art will understand that the above-described structure does not constitute a limitation on the settlement early warning system 100, and may include more or fewer components than described above, or combine certain components, or have different component arrangements.

[0069] like Figure 1 As shown, based on the subsidence early warning system 100, this embodiment of the invention provides a real-time early warning method for ground disturbance, including the following steps:

[0070] Step S10: Obtain the over-excavation volume of the tunnel boring machine in real time.

[0071] It should be noted that the over-excavation volume of the tunnel boring machine is obtained every preset time interval, and the preset time interval is set according to actual needs.

[0072] Step S20: Calculate the predicted surface settlement value at the tunnel centerline in real time based on the shield over-excavation volume and settlement trough width coefficient.

[0073] It should be noted that the over-excavation volume of the shield tunnel is the volume of tunnel loss per unit length caused by shield tunneling construction, and the over-excavation volume of the shield tunnel is denoted as V. i The settlement trough width coefficient is the abscissa of the inflection point of the settlement curve, and the settlement width coefficient is set as i. The surface settlement value at the tunnel centerline is the surface settlement value directly above the tunnel centerline, and the surface settlement value at the tunnel centerline is set as S. max The formula for calculating the surface settlement value at the centerline of the tunnel is:

[0074]

[0075] It should be noted that the settlement width coefficient can be calculated from the vertical distance from the current surface monitoring point to the tunnel centerline and the internal friction angle of the strata around the tunnel. The internal friction angle of the strata can be obtained through on-site tests before construction.

[0076] Specifically, the vertical distance is denoted as Z, the internal friction angle of the stratum is denoted as φ, and the formula for calculating the settlement trough width coefficient i is:

[0077]

[0078] Step S30: Obtain correction coefficients to correct deviations caused by shield over-excavation volume and the dispersion of geological parameters.

[0079] It should be noted that the calculated surface settlement prediction value at the tunnel centerline is a theoretical value. At the same time, the obtained shield over-excavation volume may deviate from the actual over-excavation volume, and the dispersion of geological parameters will also cause deviations in the calculated surface settlement value. Therefore, it is necessary to correct the deviations caused by the shield over-excavation volume and the dispersion of geological parameters through correction coefficients to improve the accuracy of the subsequent calculation of the surface settlement prediction value corresponding to the surface monitoring points.

[0080] Step S40: Calculate the predicted surface settlement value corresponding to the surface monitoring point in real time based on the horizontal distance from the surface monitoring point to the tunnel centerline, the correction coefficient, the predicted surface settlement value at the tunnel centerline, and the settlement trough width coefficient.

[0081] It should be noted that the horizontal distance is set as x, the correction coefficient is set as K0, the predicted surface settlement value is set as S(x), and the formula for calculating the predicted surface settlement value is:

[0082]

[0083] Step S50: Compare the predicted surface subsidence value with the warning threshold, and issue a warning signal based on the comparison result.

[0084] It should be noted that the predicted surface subsidence value corresponding to the surface monitoring point is compared with the early warning threshold in real time, and an early warning signal is issued before the stratum subsides based on the comparison result, until the construction work is completed.

[0085] In this invention, the over-excavation volume of the shield tunnel is first acquired in real time. Then, based on the over-excavation volume and the settlement trough width coefficient, the predicted surface settlement value at the tunnel centerline is calculated in real time. Next, a correction coefficient is obtained to correct the deviation caused by the over-excavation volume and the dispersion of geological parameters. Based on the horizontal distance from the surface monitoring point to the tunnel centerline, the correction coefficient, the predicted surface settlement value at the tunnel centerline, and the settlement trough width coefficient, the predicted surface settlement value corresponding to the surface monitoring point is calculated in real time. Finally, the predicted surface settlement value corresponding to the surface monitoring point is compared with the warning threshold in real time, and a warning signal is issued before the stratum subsides based on the comparison results, until the construction operation is completed. In this invention, the shield tunneling over-excavation volume is the ground over-excavation amount. The predicted ground settlement value at the tunnel centerline is calculated using the shield tunneling over-excavation volume and the settlement trough width coefficient. Then, the theoretical predicted ground settlement value for this section of the tunnel can be calculated using the horizontal distance and the predicted ground settlement value at the tunnel centerline. The deviation caused by the shield tunneling over-excavation volume and the dispersion of geological parameters is corrected by a correction coefficient, reducing the deviation between the final predicted ground settlement value and the actual settlement value. This allows for accurate issuance of early warning signals after comparing the predicted ground settlement value with the early warning threshold. Furthermore, real-time early warning of ground settlement is achieved by acquiring the predicted ground settlement value in real time and comparing it with the early warning threshold in real time.

[0086] refer to Figure 2 , Figure 2 This is a flowchart illustrating the second embodiment of the real-time early warning method for formation disturbance of the present invention.

[0087] Based on the first embodiment described above, the real-time early warning method for formation disturbance in this embodiment includes the following in step S10:

[0088] Step S11: Obtain the tunneling distance of tunnel boring machine 1.

[0089] Step S12: Calculate the design excavation volume of the shield cutterhead based on the radius of the shield cutterhead and the tunneling distance.

[0090] It should be noted that the radius of the shield cutterhead is set as r, the tunneling distance is set as l, and the designed excavation volume is set as V. r The formula for calculating the designed excavation volume is:

[0091]

[0092] Step S13: Obtain the grouting volume and grouting loss coefficient of tunnel boring machine 1.

[0093] It should be noted that the grouting volume can be obtained by the grouting metering device of the tunnel boring machine 1, and the grouting loss coefficient can be obtained by referring to a table.

[0094] Step S14: Obtain the corrected slag volume.

[0095] Step S15: Calculate the shield over-excavation volume based on the corrected slag discharge volume, the designed excavation volume, the grouting volume, the grouting loss coefficient, and the tunneling distance.

[0096] It should be noted that the corrected slag discharge volume is set as V. c The grouting volume is set as V. g The grouting loss coefficient is set as k, and the shield over-excavation volume V i The calculation formula is:

[0097]

[0098] refer to Figure 3 , Figure 3 This is a flowchart illustrating the third embodiment of the real-time early warning method for formation disturbance of the present invention.

[0099] Based on the second embodiment described above, the real-time early warning method for formation disturbance in this embodiment includes the following in step S14:

[0100] Step S141: Obtain the actual over-excavation volume.

[0101] It should be noted that, as Figure 11 and Figure 12 As shown, the over-excavation outline can be obtained by detecting and analyzing the muon density imaging device 2 and the ground-penetrating radar 3, and then the actual over-excavation volume can be calculated. The specific acquisition process is existing technology, so it will not be described in detail.

[0102] Step S142: Calculate the first slag discharge volume based on the designed excavation volume and the actual over-excavation volume.

[0103] It should be noted that the first slag discharge volume is the sum of the designed excavation volume and the actual over-excavation volume.

[0104] Step S143: Obtain the volume of slag discharged from the virtual container.

[0105] Step S144: Obtain the volume of slurry in the slag.

[0106] Step S145: Obtain the formation loosening coefficient.

[0107] It should be noted that the stratigraphic looseness coefficient can be obtained through field experiments and geological survey reports.

[0108] Step S146: Calculate the second slag discharge volume based on the virtual slag discharge volume, the slurry volume, and the formation loosening coefficient.

[0109] It should be noted that the volume of the slag discharged from the virtual cubic meter is set as V1, and the volume of the slurry is set as V. m Let the formation loosening coefficient be n, and the second slag discharge volume be V2. The formula for calculating the second slag discharge volume is:

[0110]

[0111] Step S147: Calculate the slag discharge difference ratio based on the first slag discharge volume and the second slag discharge volume.

[0112] It should be noted that the slag discharge difference ratio can be obtained by dividing the absolute value of the difference between the first slag discharge volume and the second slag discharge volume by the first slag discharge volume.

[0113] Step S148: If the slag discharge difference ratio is less than the first preset threshold, then the first slag discharge volume is used as the corrected slag discharge volume.

[0114] It should be noted that the first preset threshold can be set by the operator according to actual needs. In this embodiment, the first preset threshold is set to 5%. The corrected slag volume can be obtained by calculating the first slag volume and the second slag volume. The values ​​obtained by the two methods are verified against each other. If the slag difference ratio is less than 5%, it indicates that the error is small. Therefore, the first slag volume can be used as the corrected slag volume, and the second slag volume can also be used as the corrected slag volume.

[0115] Step S149: If the slag discharge difference ratio is greater than the first preset threshold, then re-acquire the actual over-excavation volume and the virtual slag discharge volume until the slag discharge difference ratio is less than the first preset threshold.

[0116] refer to Figure 4 , Figure 4 This is a flowchart illustrating the fourth embodiment of the real-time early warning method for formation disturbance of the present invention.

[0117] Based on the third embodiment described above, the real-time early warning method for formation disturbance in this embodiment includes the following in step S143:

[0118] Step S1431: Obtain the average weight of the excavated soil within a preset time period.

[0119] It should be noted that, as Figure 13As shown, the excavated soil 300 is output from the slag outlet of the tunnel boring machine 1 and falls onto the conveyor belt 5. Multiple excavated soil weight values ​​can be obtained in real time through the conveyor belt 5. The average weight of the excavated soil within a preset time can be calculated based on the multiple excavated soil weight values. Theoretically, each excavated soil weight value is the same.

[0120] Step S1432: Obtain the average volume of slag and soil within a preset time period.

[0121] It should be noted that, as Figure 13 As shown, since the conveyor belt 5 is within the detection range of the three-dimensional laser scanner 4, multiple slag volume values ​​can be obtained in real time through the three-dimensional laser scanner 4. Since the slag 300 contains mud, the slag particles cannot be stably piled up, and the slag volume value obtained in a single scan may be too large or too small. Therefore, it is necessary to obtain the average volume of slag within a preset time.

[0122] Step S1433: Calculate the dynamic bulk density of the slag based on the average weight and average volume of the slag.

[0123] It should be noted that by obtaining the dynamic bulk density of slag 300 within a preset time, the error caused by a single fluctuation in slag volume can be reduced.

[0124] Step S1434: Obtain the current weight of 300 tons of slag.

[0125] It should be noted that, theoretically, the current weight of 300 cubic meters of construction waste is equal to the average weight of construction waste.

[0126] Step S1435: Calculate the virtual slag discharge volume based on the current weight and the dynamic bulk density.

[0127] refer to Figure 5 , Figure 5 This is a flowchart illustrating the fifth embodiment of the real-time early warning method for formation disturbance of the present invention.

[0128] Based on the third embodiment described above, the real-time early warning method for formation disturbance in this embodiment includes the following in step S144:

[0129] Step S1441: Obtain the filling coefficient and mud density.

[0130] It should be noted that the filling coefficient can be obtained through field tests and empirical data, and the mud density can be determined based on mud mix ratio tests.

[0131] Step S1442: Calculate the discharge volume based on the designed excavation volume, the filling coefficient, and the mud density.

[0132] It should be noted that the filling coefficient is denoted as η, the mud density as ρ, the discharge volume as V3, and the formula for calculating the discharge volume is:

[0133]

[0134] Step S1443: Calculate the grout-containing volume based on the grouting volume and the grout discharge volume.

[0135] It should be noted that the slurry volume is equal to the grouting volume minus the slurry discharge volume.

[0136] like Figure 6 As shown, based on the aforementioned real-time early warning method for ground disturbance, this embodiment of the invention also provides a tunnel early warning method, comprising the following steps:

[0137] Step S100: Divide the entire tunnel into multiple sections and set up surface monitoring points for each section.

[0138] Step S200: Based on the correction coefficient corresponding to this tunnel section, the real-time early warning method for ground disturbance is used to obtain the predicted value of surface subsidence corresponding to the surface monitoring point of this tunnel section in real time.

[0139] It should be noted that the correction coefficient for the first tunnel section can be obtained by collecting historical data from similar projects, and then selecting a lightweight regression model such as XGBoost as a machine learning model. Historical characteristic data such as the corrected slag volume and grouting volume of similar strata can be input into the model to output the initial correction coefficient.

[0140] Step S400: Compare the predicted surface subsidence value with the early warning threshold in real time, and issue an early warning signal before the stratum subsides based on the comparison result, until the tunnel section is completed.

[0141] Step S500: Obtain the corresponding correction coefficient for the next tunnel segment, and use the above method to provide real-time early warning of ground disturbance until the entire tunnel construction is completed.

[0142] It should be noted that after completing the construction of one tunnel segment, the corresponding correction coefficient for the next tunnel segment is obtained. The correction coefficient is continuously iterated and learned to continuously reduce the deviation between the predicted and actual settlement values ​​of the ground surface settlement in each tunnel segment.

[0143] refer to Figure 7 , Figure 7 This is a flowchart illustrating the second embodiment of the tunnel early warning method of the present invention.

[0144] Based on the first embodiment described above, the tunnel early warning method of this embodiment includes the following in step S500:

[0145] Step S510: After the construction of this section of the tunnel is completed and a preset time has elapsed, obtain the measured values ​​of surface settlement corresponding to the surface monitoring points of this section of the tunnel, and calculate the settlement deviation value and settlement difference ratio based on the measured values ​​of surface settlement and the predicted values ​​of surface settlement.

[0146] It should be noted that during construction, the entire tunnel is divided into multiple sections, and each section is equipped with a corresponding surface monitoring point. The measured surface settlement value can be obtained by the settlement monitoring device installed at the corresponding surface monitoring point. The settlement deviation value is the absolute value of the difference between the measured surface settlement value and the predicted surface settlement value, and the settlement difference ratio is the ratio of the settlement deviation value to the measured surface settlement value.

[0147] Step S520: If the settlement difference ratio is less than the second preset threshold, the current correction coefficient is used as the corresponding correction coefficient for calculating the next tunnel segment.

[0148] It should be noted that the second preset threshold can be set according to actual construction needs. In this embodiment, the second preset threshold is 5%. If the settlement difference ratio is less than 5%, it indicates that the current correction coefficient has a high accuracy and can be used as a correction coefficient when calculating the predicted surface settlement value of the next tunnel section.

[0149] Step S530: If the settlement difference ratio is greater than the second preset threshold, the settlement deviation value, the corrected slag volume and the grouting volume are input into the machine learning model, and the model outputs the iterative correction coefficient. The iterative correction coefficient is then used as the corresponding correction coefficient for calculating the next tunnel section.

[0150] It should be noted that historical data from similar projects are first collected. Then, a lightweight regression model such as XGBoost is selected as the machine learning model. Historical characteristic data such as the corrected muck volume and grouting volume of similar strata are input into the model to output initial correction coefficients. These initial correction coefficients are used as correction coefficients when calculating the predicted surface settlement value of the first tunnel segment. If the settlement difference ratio is greater than 5%, it indicates that the current correction coefficient has low accuracy. Since the corrected muck volume is the core characterization of stratum disturbance, directly reflecting the scale of stratum disturbance caused by the actual excavation and over-excavation of the shield tunnel, it is the most critical construction parameter leading to settlement deviation. The grouting volume is the core characterization of stratum compensation, directly reflecting the filling effect of the void behind the wall, and is the core construction parameter for offsetting settlement and reducing deviation. The settlement deviation value is the driving force for iterative learning. Therefore, the settlement deviation value, the corrected muck volume, and the grouting volume are input into the machine learning model to output iterative correction coefficients, and these iterative correction coefficients are used as the corresponding correction coefficients for calculating the next tunnel segment.

[0151] refer to Figure 8 , Figure 8This is a flowchart illustrating the third embodiment of the tunnel early warning method of the present invention.

[0152] Based on the first embodiment described above, the tunnel early warning method of this embodiment further includes, after step S200:

[0153] Step S300: Determine the warning level based on the predicted surface subsidence value and the warning threshold, and determine the adjustment strategies for grouting volume, tunnel boring machine thrust, tunnel boring machine torque and tunneling speed based on the warning level.

[0154] It should be noted that the warning level is graded and the parameters of the tunnel boring machine 1 are adjusted accordingly to slow down the subsidence trend of the strata and control the development of subsidence.

[0155] refer to Figure 9 , Figure 9 This is a flowchart illustrating the fourth embodiment of the tunnel early warning method of the present invention.

[0156] Based on the third embodiment described above, the tunnel early warning method of this embodiment includes the following in step S300:

[0157] Step S310: When the predicted value of surface subsidence is less than 0.8 times the warning threshold, the warning level is determined to be normal, and the initial grouting volume, initial shield machine thrust, initial shield machine torque and initial tunneling speed are maintained.

[0158] It should be noted that when the predicted value of surface subsidence is less than 0.8 times the warning threshold, it indicates that the stratum disturbance is mild and the compensation is sufficient, and no parameter adjustment is required.

[0159] Step S320: When the predicted value of surface subsidence is less than the warning threshold and greater than 0.8 times the warning threshold, the warning level is determined to be warning level, and the grouting volume is adjusted to the first preset volume, the shield machine thrust is adjusted to the first preset thrust, the shield machine torque is adjusted to the first preset torque, and the initial tunneling speed is maintained.

[0160] It should be noted that when the predicted surface settlement value is less than the warning threshold but greater than 0.8 times the warning threshold, weak compensation and slight disturbance reduction are required. Therefore, the first preset volume is 110% to 120% of the initial grouting volume, that is, the initial grouting volume is increased by 10% to 20%; the first preset thrust is 88% to 92% of the initial shield machine thrust, that is, the initial shield machine thrust is reduced by 8% to 12%, and the center thrust of the cutterhead is reduced first, while the corrected muck discharge is obtained in real time. If the corrected muck discharge still increases, it is further reduced by 5%; the first preset torque is 88% to 92% of the initial shield machine torque, that is, the initial shield machine torque is reduced by 8% to 12%, and the reduction in torque is consistent with the reduction in thrust.

[0161] Step S330: When the predicted value of surface subsidence is greater than the warning threshold, the warning level is determined to be emergency level, and the grouting volume is adjusted to the second preset volume, the shield machine thrust is adjusted to the second preset thrust, the shield machine torque is adjusted to the second preset torque, and the tunneling speed is adjusted to the preset speed.

[0162] It should be noted that when the predicted surface settlement value is greater than the warning threshold, it is inferred that there is excessive over-excavation or insufficient grouting, requiring strong compensation and a significant reduction in disturbance. Therefore, the second preset volume is 120% to 130% of the initial grouting volume, that is, the initial grouting volume is increased by 20% to 30%, and advanced grouting is initiated simultaneously; the second preset thrust is 75% to 85% of the initial shield machine thrust, that is, the initial shield machine thrust is reduced by 15% to 25%; the preset speed is 50% to 70% of the initial tunneling speed, that is, the initial tunneling speed is reduced by 30% to 50%; the second preset torque is 75% to 85% of the initial shield machine torque, that is, the initial shield machine torque is reduced by 15% to 25%, and the reduction in torque is consistent with the reduction in thrust.

[0163] It should be noted that the predicted surface settlement value corresponding to the surface monitoring point is obtained in real time. If the predicted surface settlement value changes and meets the conditions of other warning levels, the warning level will change accordingly, and the adjustment strategy of each parameter of the tunnel boring machine 1 will change accordingly.

[0164] It should be understood that although the steps in the flowcharts of this application's embodiments are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some of the steps in the figures may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times, and their execution order is not necessarily sequential, but can be performed alternately or in turn with other steps or at least a portion of the sub-steps or stages of other steps.

[0165] It should be understood that the above are merely illustrative examples and do not constitute any limitation on the technical solutions of the present invention. In specific applications, those skilled in the art can make settings as needed, and the present invention does not impose any restrictions on this.

[0166] It should be noted that the workflow described above is merely illustrative and does not limit the scope of protection of this invention. In practical applications, those skilled in the art can select some or all of the workflow to achieve the purpose of this embodiment according to actual needs, and no restrictions are imposed here.

[0167] Furthermore, it should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

[0168] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0169] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A real-time alert method for formation disturbance, characterized in that, Includes the following steps: Real-time acquisition of shield tunnel over-excavation volume; Real-time calculation of the predicted surface settlement at the tunnel centerline based on the shield over-excavation volume and settlement trough width coefficient; Obtain correction coefficients to correct deviations caused by shield over-excavation volume and the dispersion of geological parameters; The predicted surface settlement value corresponding to the surface monitoring point is calculated in real time based on the horizontal distance from the surface monitoring point to the tunnel centerline, the correction coefficient, the predicted surface settlement value at the tunnel centerline, and the settlement trough width coefficient. The predicted surface subsidence value corresponding to the surface monitoring point is compared with the early warning threshold in real time, and an early warning signal is issued before the stratum subsides based on the comparison result, until the construction work is completed.

2. The real-time formation disturbance alert method of claim 1, wherein, The real-time acquisition of shield tunnel over-excavation volume includes: Obtain the tunneling distance of the tunnel boring machine; The design excavation volume of the shield cutterhead is calculated based on the radius of the shield cutterhead and the tunneling distance. Obtain the grouting volume and grouting loss coefficient of the tunnel boring machine; Obtain the corrected slag volume; The over-excavation volume of the shield tunnel is calculated based on the corrected slag discharge volume, the designed excavation volume, the grouting volume, the grouting loss coefficient, and the tunneling distance.

3. The real-time early warning method for formation disturbance as described in claim 2, characterized in that, The process of obtaining the corrected slag volume includes: Obtain the actual over-excavation volume; The first slag discharge volume is calculated based on the designed excavation volume and the actual over-excavation volume. Obtain the volume of slag discharged from the virtual square; To obtain the volume of slurry in the slag; Obtain the formation looseness coefficient; The second slag discharge volume is calculated based on the virtual slag discharge volume, the slurry volume, and the formation loosening coefficient. The ratio of slag discharge difference is calculated based on the first slag discharge volume and the second slag discharge volume. If the slag discharge difference ratio is less than the first preset threshold, then the first slag discharge volume is used as the corrected slag discharge volume; If the slag discharge difference ratio is greater than the first preset threshold, the actual over-excavation volume and the virtual slag discharge volume are re-acquired until the slag discharge difference ratio is less than the first preset threshold.

4. The real-time early warning method for formation disturbance as described in claim 3, characterized in that, The process of obtaining the volume of the slag discharged from the virtual cubic meter includes: Obtain the average weight of the construction waste within a preset time period; Obtain the average volume of construction waste within a preset time period; The dynamic bulk density of the waste soil is calculated based on the average weight and average volume of the waste soil. Get the current weight of the construction waste; The virtual slag discharge volume is calculated based on the current weight and the dynamic bulk density.

5. The real-time early warning method for formation disturbance as described in claim 3, characterized in that, The process of obtaining the slurry volume in the slag includes: Obtain the filling coefficient and mud density; The discharge volume is calculated based on the designed excavation volume, the filling coefficient, and the mud density. The grout-containing volume is calculated based on the grouting volume and the grout discharge volume.

6. A tunnel early warning method, characterized in that, Includes the following steps: The entire tunnel was divided into multiple sections, and surface monitoring points were set up for each section. Based on the correction coefficient corresponding to this tunnel section, the real-time early warning method for stratum disturbance as described in any one of claims 1 to 5 is used to obtain the predicted value of surface subsidence corresponding to the surface monitoring point of this tunnel section in real time. The predicted surface subsidence value is compared with the early warning threshold in real time, and an early warning signal is issued before the stratum subsides based on the comparison results, until the tunnel section is completed. Obtain the corresponding correction coefficient for the next tunnel segment, and use the above method to provide real-time early warning of ground disturbance until the entire tunnel construction is completed.

7. The tunnel early warning method as described in claim 6, characterized in that, The step of obtaining the corresponding correction coefficient for the next tunnel segment includes: After the tunnel section is completed and a preset time has elapsed, the measured values ​​of surface settlement corresponding to the surface monitoring points of the tunnel section are obtained, and the settlement deviation value and settlement difference ratio are calculated based on the measured values ​​of surface settlement and the predicted values ​​of surface settlement. If the settlement difference ratio is less than the second preset threshold, the current correction coefficient will be used as the corresponding correction coefficient for calculating the next tunnel segment. If the settlement difference ratio is greater than the second preset threshold, the settlement deviation value, the corrected slag volume and the grouting volume are input into the machine learning model, which outputs the iterative correction coefficient, and the iterative correction coefficient is used as the corresponding correction coefficient for calculating the next tunnel section.

8. The tunnel early warning method as described in claim 6, characterized in that, After obtaining the predicted surface settlement values ​​corresponding to the surface monitoring points of this tunnel section, the method further includes: The warning level is determined based on the predicted surface subsidence value and the warning threshold, and the adjustment strategies for grouting volume, tunnel boring machine thrust, tunnel boring machine torque and tunneling speed are determined based on the warning level.

9. The tunnel early warning method as described in claim 8, characterized in that, The method for determining the early warning level based on the predicted surface subsidence value and the early warning threshold, and determining the adjustment strategy for grouting volume, tunnel boring machine thrust, tunnel boring machine torque, and tunneling speed based on the early warning level, includes: When the predicted surface settlement value is less than 0.8 times the warning threshold, the warning level is determined to be normal, and the initial grouting volume, initial shield machine thrust, initial shield machine torque and initial tunneling speed are maintained. When the predicted value of surface subsidence is less than the warning threshold but greater than 0.8 times the warning threshold, the warning level is determined to be warning level, and the grouting volume is adjusted to the first preset volume, the shield machine thrust is adjusted to the first preset thrust, the shield machine torque is adjusted to the first preset torque, and the initial tunneling speed is maintained. When the predicted value of surface subsidence is greater than the warning threshold, the warning level is determined to be emergency level, and the grouting volume is adjusted to the second preset volume, the shield machine thrust is adjusted to the second preset thrust, the shield machine torque is adjusted to the second preset torque, and the tunneling speed is adjusted to the preset speed. Among them, the initial grouting volume < the first preset volume < the second preset volume, the initial shield machine thrust > the first preset thrust > the second preset thrust, the initial shield machine torque > the first preset torque > the second preset torque, and the initial tunneling speed > the preset speed.

10. A real-time settlement early warning system for tunnel construction, based on the real-time ground disturbance early warning method as described in any one of claims 1 to 5, characterized in that, The system includes a control center, a tunnel boring machine (TBM), a muon density imaging device, a ground-penetrating radar (GPR), a 3D laser scanner, a conveyor belt, and multiple settlement monitoring devices corresponding to various surface monitoring points. The muon density imaging device, the GPR, and the 3D laser scanner are all mounted on the TBM. The conveyor belt is located on the discharge side of the TBM's slag outlet and is within the detection range of the 3D laser scanner. The TBM's grouting metering device, the muon density imaging device, the GPR, the 3D laser scanner, the conveyor belt, and the multiple settlement monitoring devices are all electrically connected to the control center.

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