A method for real-time identification of stratum characteristics and dynamic adjustment of tunneling parameters based on cutterhead dynamic response

Abstract

The present invention discloses a method for real-time identification of stratum characteristics and dynamic adjustment of excavation parameters based on the dynamic response of the cutterhead, which belongs to the field of tunnel and underground engineering technology, realizes real-time automatic monitoring of changes in stratum characteristics during excavation, and gives excavation adjustment suggestions. Specifically, the following steps are included: Step 1: Install a three-axis vibration sensor on the cutterhead of a shield machine, and ensure that the three directions of the three-axis vibration sensor X, Y, and Z are consistent with the three directions of shield excavation during installation, wherein the X direction is the shield excavation direction, the Y direction is the horizontal direction, and the Z direction is the vertical downward direction; Step 2: The signal collector receives, stores, and uploads the cutterhead acceleration response data collected by the three-axis vibration sensor in real time; Step 3: The vibration analysis and processing module identifies four different characteristics of strata, namely, full-section hard rock, upper soft and lower hard strata, clay strata, and fault fracture zone, based on the cutterhead acceleration response data, and makes dynamic adjustments.

Description

Technical Field

[0001] The present invention specifically relates to a method for real-time identification of stratum characteristics and dynamic adjustment of excavation parameters based on the dynamic response of a cutterhead, and belongs to the technical field of tunnel and underground engineering. Background Art

[0002] With the continuous development and utilization of underground space in domestic cities, shield tunnel projects will develop into deeper spaces, and therefore will face many problems such as more complex geological conditions, higher groundwater pressure and longer excavation distance. In the process of slurry shield excavation, facing complex and changeable strata, it is necessary to timely identify the stratum characteristics and adjust the excavation parameters to ensure efficient and safe shield excavation.

[0003] In a slurry shield, thrust and torque are less sensitive to stratum changes, and it is impossible to timely analyze stratum characteristics through changes in thrust and torque; the method of directly opening the slurry tank to observe the excavation surface by lowering the liquid level in the slurry tank is highly risky and easily leads to instability of the excavation surface; the accuracy of the existing advanced geological prediction technology based on acoustic waves needs to be improved. The dynamic response of the cutterhead is extremely sensitive to changes in stratum characteristics. Therefore, a method is needed to achieve real-time identification of stratum characteristics during shield excavation, give excavation adjustment suggestions, and reduce tool breakage and cutterhead mud cake during shield excavation. Summary of the invention

[0004] The purpose of the present invention is to address the deficiencies in the prior art and propose a method for real-time identification of stratum characteristics and dynamic adjustment of excavation parameters based on the dynamic response of the cutterhead, which belongs to the field of tunnel and underground engineering technology, realizes real-time automatic monitoring of changes in stratum characteristics during excavation, gives excavation adjustment suggestions, and reduces tool breakage and cutterhead mud cake during shield excavation.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] A method for real-time identification of formation characteristics and dynamic adjustment of excavation parameters based on cutterhead dynamic response comprises the following steps:

[0007] Step 1: Install a triaxial vibration sensor on the cutterhead of the shield machine. During installation, ensure that the three directions of the triaxial vibration sensor X, Y, and Z are consistent with the three directions of shield excavation. The X direction is the shield excavation direction, the Y direction is the horizontal direction, and the Z direction is the vertical downward direction.

[0008] Step 2: The signal collector receives, stores and uploads the cutter head acceleration response data collected by the three-axis vibration sensor in real time;

[0009] Step 3: Based on the cutterhead acceleration response data, the vibration analysis and processing module identifies four different strata: full-section hard rock, upper soft and lower hard strata, clay strata, and fault fracture zone, and makes dynamic adjustments.

[0010] Preferably, a magnet base is provided at the bottom of the three-axis sensor, and the magnet base suction cup is on the cutter head of the shield machine.

[0011] Preferably, the signal collector is arranged at the tail of the shield and is connected to the operating room of the shield machine via a wireless network.

[0012] Furthermore, step 3 includes the following steps:

[0013] Step 3.1: First, the time domain signal of the cutter head acceleration response data is converted into a frequency domain signal through FFT transformation;

[0014] Step 3.2: Draw the frequency domain curves of frequency and acceleration at different time points in the three directions of X, Y, and Z respectively;

[0015] Step 3.3: Extract the peak value X of the acceleration time domain signal in the three directions of X, Y, and Z XP , X YP , X ZP ;

[0016] Step 3.4: Based on the frequency domain curve and the time domain signal peak, the formation identification method is used to identify four different characteristics of formations: full-section hard rock, upper soft and lower hard formations, clay formations, and fault fracture zones, and make dynamic adjustments.

[0017] Preferably, the formation identification method comprises:

[0018] ① When the acceleration response frequency concentration areas in the Y and Z directions are different, the stratum is determined to be soft on the top and hard on the bottom;

[0019] ② When the acceleration response frequency concentration areas in the Y and Z directions are the same, and the acceleration time domain signal peak value X XP , X YP , X ZP If both are less than the acceleration threshold, the stratum is determined to be a clay stratum;

[0020] ③ When the acceleration response frequency concentration areas in the Y and Z directions are the same, and the acceleration time domain signal peak value X XP , X YP , X ZP There are one or more acceleration thresholds, and X XP >X YP , X XP >X ZP , then the stratum is determined to be a full-section hard rock stratum;

[0021] ④ When the acceleration response frequency concentration areas in the Y and Z directions are the same, and the acceleration time domain signal peak value X XP , X YP , XZP There are one or more acceleration thresholds, but they do not satisfy X at the same time. XP >X YP , X XP >X ZP , then the stratum is determined to be a fault fracture zone stratum.

[0022] Furthermore, the confirmation of the response frequency concentration area includes the following steps:

[0023] Step A: Find the peak point in the response frequency whose peak value exceeds k times the average response frequency, where k is the acceptance multiple, k>1, and is a preset constant;

[0024] Step B: Calculate the distances between adjacent peak points in step A respectively;

[0025] Step C: Find the high peak points to be evaluated whose distances between adjacent high peak points exceed the distance threshold;

[0026] Step D: Determine whether the peak value to be evaluated is on the left or right side of the peak median point;

[0027] Step E: For the high peak points to be evaluated on the left, remove the high peak points to be evaluated that are located on the left side of the adjacent high peak points; for the high peak points to be evaluated on the right, remove the high peak points to be evaluated that are located on the right side of the adjacent high peak points;

[0028] Step F: Find the maximum point and the minimum point among the remaining high peak points to be evaluated. The area between the minimum point and the maximum point is the response frequency concentration area.

[0029] Alternatively, the peak value of the acceleration time domain signal can be optimized to eliminate accidental data errors:

[0030]

[0031] Among them, j is the dimension, which is one of X, Y, and Z, a is the number of high peaks, which is a constant, b is the number of low peaks, which is common sense, and X jm Arrange the mth peak value of the acceleration time domain signal from large to small, X jn Arrange the nth peak value of the acceleration time domain signal from small to large.

[0032] Preferably, a=b=4.

[0033] Furthermore, when the stratum is determined to be full-section hard rock, upper soft and lower hard stratum, or fault fracture zone, the excavation method of reducing penetration, reducing excavation speed, or low penetration and high speed mode is adopted to reduce the impact load of the tool and reduce tool breakage; when the stratum is determined to be a clay stratum, the cutter head speed is reduced to reduce the cutter head temperature field to reduce the cutter head mud cake.

[0034] Preferably, when the stratum is determined to be full-section hard rock, upper soft and lower hard stratum, or fault fracture zone, the peak value X of the acceleration response in the X direction of the cutterhead is controlled. XP At 100m / s 2 the following.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] The purpose of the present invention is to address the deficiencies in the prior art and propose a method for real-time identification of stratum characteristics and dynamic adjustment of excavation parameters based on the dynamic response of the cutterhead, which belongs to the field of tunnel and underground engineering technology, realizes real-time automatic monitoring of changes in stratum characteristics during excavation, gives excavation adjustment suggestions, and reduces tool breakage and cutterhead mud cake during shield excavation.

[0037] 1. The present invention creatively proposes a method for identifying formation characteristics through the dynamic response of the cutterhead, and judges the changes in formation characteristics through the dynamic response of the cutterhead with high accuracy.

[0038] 2. The present invention can realize real-time automatic monitoring of changes in stratum characteristics during excavation through a dynamic response real-time monitoring and analysis system.

[0039] 3. The present invention proposes excavation control suggestions based on the dynamic response results, which helps to reduce problems such as tool breakage and cutterhead mud cake during shield tunneling and achieve efficient shield tunneling.

[0040] 4. The present invention provides a new idea for intelligent shield tunneling. The solution is simple and practical, low in cost, and has high value for promotion and popularization. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a schematic diagram of the real-time monitoring and analysis system in the present invention;

[0042] Figure 2 This is a detailed diagram of the vibration sensor in the present invention;

[0043] Figure 3 It is the time domain curve provided in the present invention;

[0044] Figure 4 It is the frequency domain curve provided in the present invention;

[0045] Figure 5 It is an analysis flow chart of a method for real-time identification of formation characteristics and dynamic adjustment of excavation parameters based on the dynamic response of the cutterhead in the present invention;

[0046] Figure 6 The proportion of soil and rock when opening the warehouse to check the excavation surface in the present invention;

[0047] Figure 7It is the full-section hard rock formation time domain curve provided in the present invention;

[0048] Figure 8 It is the full-section hard rock formation frequency domain curve provided in the present invention;

[0049] Fig. 9 This is a step diagram of a method for real-time identification of stratum characteristics and dynamic adjustment of excavation parameters based on the dynamic response of the cutterhead of the present invention.

[0050] The meaning of the symbols in the figure is:

[0051] a: Cutter disc, b: Cutter disc main bearing, c: Vibration sensor, d: Signal collector, e: Cloud database, f: Vibration analysis and processing module, g: Strong magnet base, h: Sensor core device. DETAILED DESCRIPTION

[0052] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0053] Example 1

[0054] A method for real-time identification of formation characteristics and dynamic adjustment of excavation parameters based on the dynamic response of the cutterhead, such as Fig. 9 As shown, the following steps are included:

[0055] Step 1: Install a triaxial vibration sensor on the cutterhead of the shield machine. During installation, ensure that the three directions of the triaxial vibration sensor X, Y, and Z are consistent with the three directions of shield excavation. The X direction is the shield excavation direction, the Y direction is the horizontal direction, and the Z direction is the vertical downward direction.

[0056] Step 2: The signal collector receives, stores and uploads the cutter head acceleration response data collected by the three-axis vibration sensor in real time;

[0057] Step 3: Based on the cutterhead acceleration response data, the vibration analysis and processing module identifies four different strata: full-section hard rock, upper soft and lower hard strata, clay strata, and fault fracture zone, and makes dynamic adjustments.

[0058] Preferably, a magnet base is provided at the bottom of the three-axis sensor, and the magnet base suction cup is on the cutter head of the shield machine.

[0059] Preferably, the signal collector is arranged at the tail of the shield and is connected to the operating room of the shield machine via a wireless network.

[0060] Furthermore, step 3 includes the following steps:

[0061] Step 3.1: First, the time domain signal of the cutter head acceleration response data is converted into a frequency domain signal through FFT transformation;

[0062] Step 3.2: Draw the frequency domain curves of frequency and acceleration at different time points in the three directions of X, Y, and Z respectively;

[0063] Step 3.3: Extract the peak value X of the acceleration time domain signal in the three directions of X, Y, and Z XP , X YP , X ZP ;

[0064] Step 3.4: Based on the frequency domain curve and the time domain signal peak, the formation identification method is used to identify four different characteristics of formations: full-section hard rock, upper soft and lower hard formations, clay formations, and fault fracture zones, and make dynamic adjustments.

[0065] Preferably, the formation identification method comprises:

[0066] ① When the acceleration response frequency concentration areas in the Y and Z directions are different, the stratum is determined to be soft on the top and hard on the bottom;

[0067] ② When the acceleration response frequency concentration areas in the Y and Z directions are the same, and the acceleration time domain signal peak value X XP , X YP , X ZP If both are less than the acceleration threshold, the stratum is determined to be a clay stratum;

[0068] ③ When the acceleration response frequency concentration areas in the Y and Z directions are the same, and the acceleration time domain signal peak value X XP , X YP , X ZP There are one or more acceleration thresholds, and X XP >X YP , X XP >X ZP , then the stratum is determined to be a full-section hard rock stratum;

[0069] ④ When the acceleration response frequency concentration areas in the Y and Z directions are the same, and the acceleration time domain signal peak value X XP , X YP , X ZP There are one or more acceleration thresholds, but they do not satisfy X at the same time. XP >X YP , X XP >X ZP, then it is determined that the stratum is a fault fracture zone stratum.

[0070] Furthermore, the confirmation of the response frequency concentration area includes the following steps:

[0071] Step A: Find the peak point in the response frequency whose peak value exceeds k times the average response frequency, where k is the acceptance multiple, k>1, and is a preset constant;

[0072] Step B: Calculate the distances between adjacent peak points in step A respectively;

[0073] Step C: Find the high peak points to be evaluated whose distances between adjacent high peak points exceed the distance threshold;

[0074] Step D: Determine whether the peak value to be evaluated is on the left or right side of the peak median point;

[0075] Step E: For the high peak points to be evaluated on the left, remove the high peak points to be evaluated that are located on the left side of the adjacent high peak points; for the high peak points to be evaluated on the right, remove the high peak points to be evaluated that are located on the right side of the adjacent high peak points;

[0076] Step F: Find the maximum point and the minimum point among the remaining high peak points to be evaluated. The area between the minimum point and the maximum point is the response frequency concentration area.

[0077] Furthermore, when the stratum is determined to be full-section hard rock, upper soft and lower hard stratum, or fault fracture zone, the excavation method of reducing penetration, reducing excavation speed, or low penetration and high speed mode is adopted to reduce the impact load of the tool and reduce tool breakage; when the stratum is determined to be a clay stratum, the cutter head speed is reduced to reduce the cutter head temperature field to reduce the cutter head mud cake.

[0078] Preferably, when the stratum is determined to be full-section hard rock, upper soft and lower hard stratum, or fault fracture zone, the peak value X of the acceleration response in the X direction of the cutterhead is controlled. XP At 100m / s 2 the following.

[0079] Example 2

[0080] The difference between Example 4 and Example 3 is that the peak value of the acceleration time domain signal is optimized to eliminate accidental data errors.

[0081] Specifically, a method for real-time identification of formation characteristics and dynamic adjustment of excavation parameters based on the dynamic response of the cutterhead includes the following steps:

[0082] Step 1: Install a triaxial vibration sensor on the cutterhead of the shield machine. During installation, ensure that the three directions of the triaxial vibration sensor X, Y, and Z are consistent with the three directions of shield excavation. The X direction is the shield excavation direction, the Y direction is the horizontal direction, and the Z direction is the vertical downward direction.

[0083] Step 2: The signal collector receives, stores and uploads the cutter head acceleration response data collected by the three-axis vibration sensor in real time;

[0084] Step 3: Based on the cutterhead acceleration response data, the vibration analysis and processing module identifies four different strata: full-section hard rock, upper soft and lower hard strata, clay strata, and fault fracture zone, and makes dynamic adjustments.

[0085] Preferably, a magnet base is provided at the bottom of the three-axis sensor, and the magnet base suction cup is on the cutter head of the shield machine.

[0086] Preferably, the signal collector is arranged at the tail of the shield and is connected to the operating room of the shield machine via a wireless network.

[0087] Furthermore, step 3 includes the following steps:

[0088] Step 3.1: First, the time domain signal of the cutter head acceleration response data is converted into a frequency domain signal through FFT transformation;

[0089] Step 3.2: Draw the frequency domain curves of frequency and acceleration at different time points in the three directions of X, Y, and Z respectively;

[0090] Step 3.3: Extract the peak value X of the acceleration time domain signal in the three directions of X, Y, and Z XP , X YP , X ZP ;

[0091] Step 3.4: Based on the frequency domain curve and the time domain signal peak, the formation identification method is used to identify four different characteristics of formations: full-section hard rock, upper soft and lower hard formations, clay formations, and fault fracture zones, and make dynamic adjustments.

[0092] Optimize the peak value of the acceleration time domain signal to eliminate accidental data errors:

[0093]

[0094] Among them, j is the dimension, which is one of X, Y, and Z, a is the number of high peaks, which is a constant, b is the number of low peaks, which is common sense, and X jm Arrange the mth peak value of the acceleration time domain signal from large to small, X jn Arrange the nth peak value of the acceleration time domain signal from small to large.

[0095] Preferably, a=b=4.

[0096] Example 3

[0097] The embodiment of the present invention provides a method for real-time identification of stratum features and dynamic adjustment of excavation parameters based on the dynamic response of the cutterhead, which is used for feature identification during shield tunneling. Specifically, it includes the following steps:

[0098] S1: Figure 1 The real-time monitoring and analysis system of dynamic response is arranged on the slurry shield machine. a is the cutterhead of the shield machine, b is the main bearing of the cutterhead, c is a three-axis wireless vibration sensor, which is adsorbed on the cutterhead bearing of the shield machine through a strong magnet. It is produced by Far East Vibration Measurement (Beijing) System Engineering Technology Co., Ltd. and the model is iVS101. The three-axis vibration sensor is used to obtain the dynamic response data of the cutterhead in the three directions of X, Y, and Z, where the X direction is the shield excavation direction, the Y direction is the horizontal direction, and the Z direction is the vertical downward direction; d is a signal collector, which is suspended at the tail of the shield and connected to the shield machine operation room through a wireless network. It is used to receive, store and upload the acceleration response data of the cutterhead collected by the vibration sensor in real time; e is a cloud database for real-time data storage, and f is a vibration analysis and processing module, which is produced by Far East Vibration Measurement (Beijing) System Engineering Technology Co., Ltd. and is used to process the dynamic response data in the cloud database in real time.

[0099] S2: Figure 2 Detailed diagram of the vibration sensor provided in the embodiment of the present disclosure, where h is a strong magnet base that can be quickly and easily adsorbed on the cutter disc bearing to ensure that the sensor's X, Y, and Z directions are consistent with the cutter disc's X, Y, and Z directions.

[0100] S3: Figure 3 The time domain curves of the acceleration of the cutterhead in the three directions of X, Y, and Z obtained by the vibration analysis processing module when the shield machine passes through a certain stratum in the embodiment of the present disclosure. The wireless vibration sensor records 1000 cutterhead acceleration response values ​​within 0.5s and finally transmits them to the vibration analysis processing module. In order to eliminate the accidental error of the data as much as possible, the vibration analysis processing module takes the peak value X of the time domain signal p for:

[0101]

[0102] Among them, X m1 , X m2 , X m3 , X m4 are the four maximum values ​​among 1000 acceleration responses, X n1 , X n2 , X n3 , X n4 , are the four minimum values ​​among the 1000 acceleration responses.

[0103] Calculate the peak value X of the time domain curve in three directions XP , X YP , X ZP 3m / s respectively 2 , 4.3m / s 2 and 3.5m / s 2 , both greater than 2m / s 2 .

[0104] S4: Figure 4 It is a frequency domain curve obtained by Fourier transform of the vibration analysis processing module when the shield machine passes through a certain stratum in the embodiment of the present disclosure. Figure 4 From the frequency domain curve in , we can see that the response frequencies in the Y direction and the Z direction are different. There are multiple response frequencies in the Y direction, while the response frequency in the Z direction is between 300 and 400 Hz.

[0105] S5: Figure 5 An analysis flow chart of a method for real-time identification of stratum characteristics and dynamic adjustment of excavation parameters based on the dynamic response of the cutterhead is provided in an embodiment of the present disclosure. According to the flow chart, it can be quickly determined whether the current shield excavation stratum is a soft upper stratum and a hard lower stratum.

[0106] S6: Determine that the stratum is soft on the top and hard on the bottom. It is advisable to reduce the penetration, reduce the excavation speed, and excavate in a low penetration and high speed mode. Adjust the excavation parameters and control the peak value of the acceleration response X in the X direction of the cutterhead. XP At 100m / s 2 The following can reduce the impact load on the tool and reduce tool breakage.

[0107] S7: Figure 6 This is the soil-rock ratio of the tunnel face when the shield machine is opened for inspection when it passes through a certain stratum in the disclosed embodiment. The soil-rock ratio in the Y direction and the Z direction is very different, and the rock breaking load of the roller cutter is different in the Y direction and the Z direction, which leads to different response frequencies of the cutterhead in the Y direction and the Z direction. There are multiple response frequencies in the Y direction, and the response frequency in the Z direction is 300-400HZ, which verifies the rationality of the analysis in this embodiment.

[0108] Example 4

[0109] S1: Figure 7 The time domain curves of the acceleration of the cutterhead in the three directions of X, Y, and Z obtained by the vibration analysis processing module when the shield machine passes through a certain stratum in the embodiment of the present disclosure. The wireless vibration sensor records 1000 cutterhead acceleration response values ​​within 0.5s and finally transmits them to the vibration analysis processing module. In order to eliminate the accidental error of the data as much as possible, the vibration analysis processing module takes the peak value X of the time domain signal p for:

[0110]

[0111] Among them, X m1 , X m2 , X m3 , X m4 are the four maximum values ​​among 1000 acceleration responses, X n1 , X n2 , X n3 , X n4 , are the four minimum values ​​among the 1000 acceleration responses.

[0112] Calculate the peak value X of the time domain curve in three directions XP , X YP , X ZP 148.3m / s respectively 2 、41.5m / s 2 and 20.4m / s 2 , both greater than 2m / s 2 , and at the same time satisfy X XP >X YP , X XP >X ZP .

[0113] S2: Figure 8 It is a frequency domain curve obtained by Fourier transform of the vibration analysis processing module when the shield machine passes through a certain stratum in the embodiment of the present disclosure. Figure 8 From the frequency domain curves in , we can see that the response frequencies in the Y and Z directions are basically the same, concentrated in the range of 500 to 1000 Hz.

[0114] S3: Basis Figure 5 The analysis flow chart can quickly determine whether the current shield tunneling stratum is a full-section hard rock stratum.

[0115] S4: Determine that the stratum is a full-section hard rock stratum. It is advisable to reduce the penetration, reduce the excavation speed, and use the low penetration and high speed mode to adjust the excavation parameters and control the peak value of the cutter head acceleration response X in the X direction. XP At 100m / s 2 The following can reduce the impact load on the tool and reduce tool breakage.

[0116] The above-mentioned embodiment only expresses one implementation mode of the present invention, and its description is relatively specific and detailed, but it cannot be understood as limiting the scope of the invention patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be based on the attached claims.

Claims

1. A method for real-time identification of stratum characteristics and dynamic adjustment of excavation parameters based on cutterhead dynamic response, characterized in that: The steps include: Step 1: Install a triaxial vibration sensor on the cutterhead of the shield machine. During installation, ensure that the three directions of the triaxial vibration sensor X, Y, and Z are consistent with the three directions of shield excavation. The X direction is the shield excavation direction, the Y direction is the horizontal direction, and the Z direction is the vertical downward direction. Step 2: The signal collector receives, stores and uploads the cutter head acceleration response data collected by the three-axis vibration sensor in real time; Step 3: The vibration analysis and processing module identifies four different strata, namely, full-section hard rock, upper soft and lower hard strata, clay strata, and fault fracture zone, based on the cutterhead acceleration response data, and makes dynamic adjustments; Step 3 includes the following steps: Step 3.1: First, the time domain signal of the cutter head acceleration response data is converted into a frequency domain signal through FFT transformation; Step 3.2: Draw the frequency domain curves of frequency and acceleration at different time points in the three directions of X, Y, and Z respectively; Step 3.3: Extract the peak value X of the acceleration time domain signal in the three directions of X, Y, and Z XP , X YP , X ZP ; Step 3.4: Based on the frequency domain curve and the time domain signal peak, the formation identification method is used to identify four formations with different characteristics: full-section hard rock, upper soft and lower hard formation, clay formation, and fault fracture zone, and make dynamic adjustments; Stratigraphic identification methods include: ① When the acceleration response frequency concentration areas in the Y and Z directions are different, the stratum is determined to be soft on the top and hard on the bottom; ② When the acceleration response frequency concentration areas in the Y and Z directions are the same, and the acceleration time domain signal peak value X XP , X YP , X ZP If both are less than the acceleration threshold, the stratum is determined to be a clay stratum; ③ When the acceleration response frequency concentration areas in the Y and Z directions are the same, and the acceleration time domain signal peak value X XP , X YP , X ZP There are one or more acceleration thresholds, and X XP >X YP , X XP >X ZP , then the stratum is determined to be a full-section hard rock stratum; ④ When the acceleration response frequency concentration areas in the Y and Z directions are the same, and the acceleration time domain signal peak value X XP , X YP , X ZP There are one or more acceleration thresholds, but they do not satisfy X at the same time. XP >X YP , X XP >X ZP , then the stratum is determined to be a fault fracture zone stratum; Optimize the peak value of the acceleration time domain signal to eliminate accidental data errors: Where j is the dimension, which is one of X, Y, and Z. a is the number of high peaks, which is a constant. b is the number of low peaks, which is a constant. X jm Arrange the mth peak value of the acceleration time domain signal from large to small, X jn Arrange the nth peak value of the acceleration time domain signal from small to large.

2. The method for real-time identification of stratum characteristics and dynamic adjustment of excavation parameters based on the dynamic response of the cutterhead according to claim 1, characterized in that: A magnet base is provided at the bottom of the triaxial vibration sensor, and the magnet base is adsorbed on the cutter head of the shield machine through a suction cup.

3. The method for real-time identification of stratum characteristics and dynamic adjustment of excavation parameters based on the dynamic response of the cutterhead according to claim 1, characterized in that: The signal collector is set at the tail of the shield and connected to the shield machine operating room via a wireless network.

4. The method for real-time identification of stratum characteristics and dynamic adjustment of excavation parameters based on the dynamic response of the cutterhead according to claim 1 is characterized in that: The confirmation of the response frequency concentration area includes the following steps: Step A: Find the peak point in the response frequency whose peak value exceeds k times the average response frequency, where k is the acceptance multiple, k>1, and is a preset constant; Step B: Calculate the distances between adjacent peak points in step A respectively; Step C: Find the high peak points to be evaluated whose distances between adjacent high peak points exceed the distance threshold; Step D: Determine whether the peak value to be evaluated is on the left or right side of the peak median point; Step E: For the high peak points to be evaluated on the left, remove the high peak points to be evaluated that are located on the left side of the adjacent high peak points; for the high peak points to be evaluated on the right, remove the high peak points to be evaluated that are located on the right side of the adjacent high peak points; Step F: Find the maximum point and the minimum point among the remaining high peak points to be evaluated. The area between the minimum point and the maximum point is the response frequency concentration area.

5. The method for real-time identification of stratum characteristics and dynamic adjustment of excavation parameters based on the dynamic response of the cutterhead according to claim 1, characterized in that: a=b=4.

6. The method for real-time identification of stratum characteristics and dynamic adjustment of excavation parameters based on the dynamic response of the cutterhead according to claim 1, characterized in that : When the stratum is determined to be full-section hard rock, soft upper and hard lower stratum, or fault fracture zone, the excavation method of reducing penetration, reducing excavation speed, or low penetration and high speed mode is adopted to reduce the impact load of the tool and reduce tool breakage; when the stratum is determined to be a clay stratum, the cutter head speed is reduced to reduce the cutter head temperature field to reduce cutter head mud cake.

7. The method for real-time identification of stratum characteristics and dynamic adjustment of excavation parameters based on the dynamic response of the cutterhead according to claim 6 is characterized by: When the stratum is determined to be full-section hard rock, upper soft and lower hard stratum, or fault fracture zone, the peak value X of the time domain signal of the cutterhead acceleration in the X direction is controlled. XP At 100m / s 2 the following.

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