A tunnel construction method based on a boom-type tunneling machine

Abstract

The application provides a tunnel construction method based on a cantilever tunneling machine, and relates to the technical field of tunnel construction.The method comprises the following steps: installing a sensing system on the cantilever tunneling machine, wherein the sensing system comprises stress sensors arranged around a cutting head, vibration sensors arranged on a machine arm, displacement sensors arranged at the connection between the cutting head and the machine arm, and acoustic emission sensors arranged at the front end of the cutting head; collecting the stress, vibration, displacement and acoustic signal data of surrounding rock detected by the sensing system; establishing a parameter optimization model according to the data, and calculating the cutting head rotating speed, the advancing speed and the cutting depth; and controlling the construction of the tunneling machine according to the parameters.The application also adopts a three-dimensional laser scanner to perform real-time monitoring on the tunneling section, and timely adjusts the construction parameters, so that the real-time monitoring of the surrounding rock state and the intelligent regulation and control of the construction parameters are realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of tunnel construction, in particular to a tunnel construction method based on a cantilever type tunneling machine. BACKGROUND

[0002] Tunnel engineering is an important part of infrastructure construction. At present, tunnel construction mainly adopts the drilling and blasting method. This method has the disadvantages of low construction efficiency, high safety risk, and large disturbance to surrounding rock, which can easily cause safety accidents and is not conducive to the smooth development of the project.

[0003] In order to overcome the shortcomings of the drilling and blasting method, people have developed a cantilever type tunneling machine for tunnel construction. Compared with the drilling and blasting method, the cantilever type tunneling machine has the advantages of high degree of mechanization and good construction continuity. However, the existing cantilever type tunneling machine still has many problems in actual application: first, the setting of construction parameters mainly depends on the experience of construction personnel, lacks scientific theoretical basis, and it is difficult to achieve optimal construction effect; second, the change of surrounding rock state cannot be sensed in real time during construction, and once the surrounding rock instability occurs, it will cause serious safety hazards; third, the disturbance to surrounding rock during construction is large, which can easily cause overbreak or underbreak phenomenon, affecting the construction quality and service life of the tunnel.

[0004] Therefore, it is urgent to provide a tunnel construction method based on a cantilever type tunneling machine to realize intelligent regulation and control of construction parameters, real-time monitoring of surrounding rock state, and effective control of construction precision. SUMMARY

[0005] The purpose of the present application is to provide a tunnel construction method based on a cantilever type tunneling machine to realize intelligent regulation and control of construction parameters, real-time monitoring of surrounding rock state, and effective control of construction precision.

[0006] To achieve the above purpose, the present application realizes the following technical scheme:

[0007] A tunnel construction method based on a cantilever type tunneling machine, comprising the following steps:

[0008] S1: installing a sensing system on the cantilever type tunneling machine, the sensing system comprising a stress sensor arranged around the cutting head, a vibration sensor arranged on the arm, a displacement sensor arranged at the connection between the cutting head and the arm, and an acoustic emission sensor arranged at the front end of the cutting head;

[0009] S2: collecting surrounding rock stress data, tunneling machine vibration data, cutting head position data and rock fracture sound signal data detected by the sensing system;

[0010] S3: establishing a parameter optimization model according to the data, and calculating the cutting head rotating speed, the advancing speed and the cutting depth;

[0011] S4: controlling the tunneling machine according to the cutting head rotation speed, the advancing speed and the cutting depth.

[0012] Further, the stress sensors are evenly arranged around the cutting head, 8 in total, with an interval of 45° between adjacent stress sensors.

[0013] Further, the vibration sensors include three-direction vibration sensors arranged at the root, middle and end of the machine arm.

[0014] Further, the acoustic emission sensors are arranged in a cross shape at the front end of the cutting head, 4 in total.

[0015] Further, the cutting head rotation speed n is calculated by the following formula:

[0016]

[0017] wherein n0 is the reference rotation speed, σ is the surrounding rock stress, σ max is the maximum allowable surrounding rock stress, v is the vibration speed, v max is the maximum allowable vibration speed, d is the displacement deviation, d max is the maximum allowable displacement deviation.

[0018] Further, the advancing speed V is calculated by the following formula:

[0019]

[0020] wherein V0 is the reference advancing speed, k1 and k2 are adjustment coefficients, σ is the surrounding rock stress, σ max is the maximum allowable surrounding rock stress, AE is the acoustic emission signal intensity, AE max is the maximum allowable acoustic emission signal intensity, θ is the rock stratum inclination.

[0021] Further, the cutting depth D is calculated by the following formula:

[0022]

[0023] wherein D0 is the reference cutting depth, α and β are adjustment coefficients, σ is the surrounding rock stress, σ max is the maximum allowable surrounding rock stress, ρ0 is the standard rock density, ρ is the actual rock density, h is the surrounding rock grade.

[0024] Further, step S4 includes: reducing the advancing speed by 20% when the monitored surrounding rock stress exceeds 85% of the set threshold; adjusting the cutting head rotation speed when the vibration amplitude exceeds the warning value; correcting the trajectory when the displacement deviation exceeds ±10mm; and dynamically adjusting the cutting depth according to the acoustic emission signal intensity.

[0025] Further, the step S4 further comprises: using a three-dimensional laser scanner to scan the tunneling section in real time, comparing the obtained actual profile data with the designed profile data; comparing the deviation between the actual profile data and the designed profile data every 1m of tunneling, and adjusting the rotation speed of the cutting head, the advancing speed and the cutting depth when the deviation exceeds ±5cm.

[0026] Compared with the prior art, the present application has the following beneficial effects:

[0027] Firstly, the device realizes multi-dimensional real-time monitoring of the surrounding rock state by arranging stress sensors, vibration sensors, displacement sensors and acoustic emission sensors on the cantilever tunneling machine, overcomes the technical defect that the traditional construction method cannot realize real-time perception of the surrounding rock state, and can effectively prevent the occurrence of construction safety accidents.

[0028] Secondly, based on the data collected by the multiple sensors, a parameter optimization model of the rotation speed of the cutting head, the advancing speed and the cutting depth is established, which gets rid of the limitation that the setting of construction parameters in the traditional construction process excessively relies on manual experience. Through the synergistic relationship between the parameters, scientific setting and intelligent control of the construction parameters can be realized.

[0029] Thirdly, the three-dimensional laser scanning technology is used to monitor the tunneling section in real time, and the construction parameters are adjusted in time according to the deviation between the actual profile and the designed profile, so as to ensure that the overbreak and underbreak precision is controlled within ±5cm, significantly improve the accuracy of tunnel construction, and effectively solve the technical problem that the traditional construction method is prone to overbreak and underbreak. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 is a flowchart schematic diagram of a tunnel construction method based on a cantilever tunneling machine in an embodiment; DETAILED DESCRIPTION

[0031] The technical solutions of the present application will be described clearly and completely below with reference to the drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0032] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third" are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0033] The tunnel construction method provided by the present application is implemented based on a boom-type tunneling machine. First, a sensing system needs to be installed on the boom-type tunneling machine. The sensing system includes stress sensors, vibration sensors, displacement sensors and acoustic emission sensors. Specifically, 8 stress sensors are uniformly arranged in the circumferential direction around the cutting head of the tunneling machine, and the interval between adjacent stress sensors is 45°, for real-time monitoring of the stress state of the surrounding rock. Three-way vibration sensors are installed at the root, middle and end of the arm, respectively, for monitoring the vibration of each part of the arm during tunneling. A displacement sensor is installed at the connection between the cutting head and the arm for accurate control of the position of the cutting head. Four acoustic emission sensors are arranged in a cross shape at the front end of the cutting head for monitoring the acoustic signals of rock fracture.

[0034] After installation, a data acquisition system is established to acquire data from each sensor. An industrial-grade PLC is used as the main control unit, the stress data acquisition frequency is set to 100Hz, the vibration data acquisition frequency is set to 1kHz, the displacement data acquisition frequency is set to 50Hz, and the acoustic emission data acquisition frequency is set to 10kHz. At the same time, a data buffer and preprocessing module is set up to filter and denoise the collected data in real time.

[0035] According to the collected data, a parameter optimization model is established to calculate the cutting head speed, advance speed and cutting depth.

[0036] wherein the cutting head speed n is calculated by the following formula:

[0037]

[0038] wherein n0 is the reference speed, σ is the surrounding rock stress, σ max is the allowable maximum surrounding rock stress, v is the vibration speed, v max is the allowable maximum vibration speed, d is the displacement deviation, d max is the allowable maximum displacement deviation.

[0039] The advance speed V is calculated by the following formula:

[0040]

[0041] wherein V0 is a reference advancing speed, k1 and k2 are adjustment coefficients, σ is a surrounding rock stress, σ max is a maximum allowable surrounding rock stress, AE is a sound emission signal intensity, AE max is a maximum allowable sound emission signal intensity, and θ is a rock stratum inclination.

[0042] The cutting depth D is calculated by the following formula:

[0043]

[0044] wherein D0 is a reference cutting depth, α and β are adjustment coefficients, σ is a surrounding rock stress, σ max is a maximum allowable surrounding rock stress, ρ0 is a standard rock density, ρ is an actual rock density, and h is a surrounding rock grade.

[0045] In the construction control process, when the surrounding rock stress is monitored to exceed 85% of the set threshold value, the advancing speed is automatically reduced by 20%; when the vibration amplitude exceeds the warning value, the cutting head rotating speed is timely adjusted; when the displacement deviation exceeds ±10 mm, the trajectory is immediately corrected; and according to the change of the sound emission signal intensity, the cutting depth is dynamically adjusted. At the same time, a three-dimensional laser scanner is used to scan the tunneling section in real time, actual profile data are obtained and compared with the designed profile data. The profile detection is performed once every 1 m of tunneling, and when the deviation between the actual profile and the designed profile exceeds ±5 cm, the cutting head rotating speed, the advancing speed and the cutting depth are timely adjusted to ensure the construction precision.

[0046] In the actual construction, the construction method of the present application is used for the construction of a certain tunnel project. The surrounding rock of the tunnel is grade III, and the rock compressive strength is 50 MPa. The initial setting of the cutting head rotating speed is 70 r / min, the advancing speed is 0.8 m / h, and the cutting depth is 80 mm. In the construction process, when the surrounding rock stress reaches 90% of the warning value, the system automatically reduces the advancing speed to 0.64 m / h; when it is detected that the vibration amplitude exceeds the warning value, the cutting head rotating speed is adjusted to 60 r / min; when the displacement deviation reaches 12 mm, the system immediately corrects the trajectory; and when the three-dimensional laser scanning detection finds that the local overbreak reaches 6 cm, the cutting depth is timely adjusted to 65 mm. By using the construction method of the present application, the construction efficiency of the tunnel project is improved by 35%, the overbreak and underbreak amount is controlled within ±5 cm, and the surrounding rock disturbance range is reduced by 45% compared with the traditional method.

[0047] The above is a brief introduction to the present application, and the present application will be described in detail through specific examples.

[0048] A tunnel construction method based on a cantilever type tunneling machine, comprising the following steps:

[0049] S1: installing a sensing system on the boom-type roadheader, the sensing system comprising stress sensors arranged around the cutting head, vibration sensors arranged on the boom, displacement sensors arranged at the connection between the cutting head and the boom, and acoustic emission sensors arranged at the front end of the cutting head;

[0050] In some embodiments, the stress sensors are evenly arranged around the cutting head at 8, with an interval of 45° between adjacent stress sensors;

[0051] In other embodiments, the vibration sensors comprise three-directional vibration sensors arranged at the root, middle and end of the boom;

[0052] The acoustic emission sensors are arranged in a cross shape at the front end of the cutting head, with 4;

[0053] S2: collecting the surrounding rock stress data, roadheader vibration data, cutting head position data and rock fracture acoustic signal data detected by the sensing system;

[0054] S3: establishing a parameter optimization model according to the data, and calculating the cutting head rotating speed, advancing speed and cutting depth;

[0055] Wherein, the cutting head rotating speed n is calculated by the following formula:

[0056]

[0057] Wherein, n0 is the reference rotating speed, σ is the surrounding rock stress, σ max is the allowable maximum surrounding rock stress, v is the vibration speed, v max is the allowable maximum vibration speed, d is the displacement deviation, d max is the allowable maximum displacement deviation.

[0058] The advancing speed V is calculated by the following formula:

[0059]

[0060] Wherein, V0 is the reference advancing speed, k1 and k2 are adjustment coefficients, σ is the surrounding rock stress, σ max is the allowable maximum surrounding rock stress, AE is the acoustic emission signal intensity, AE max is the allowable maximum acoustic emission signal intensity, θ is the rock layer inclination angle.

[0061] The cutting depth D is calculated by the following formula:

[0062]

[0063] Wherein, D0 is the reference cutting depth, α and β are adjustment coefficients, σ is the surrounding rock stress, σ maxTo allow maximum surrounding rock stress, p0 is the standard rock density, p is the actual rock density, h is the surrounding rock grade.

[0064] S4: According to the cutting head rotating speed, the advancing speed and the cutting depth, the tunneling machine is controlled.

[0065] In some embodiments, step S4 includes: when the surrounding rock stress is monitored to exceed 85% of the set threshold, the advancing speed is reduced by 20%; when the vibration amplitude exceeds the warning value, the cutting head rotating speed is adjusted; when the displacement deviation exceeds ±10mm, the trajectory is corrected; according to the acoustic emission signal strength, the cutting depth is dynamically adjusted.

[0066] In other embodiments, step S4 further includes: using a three-dimensional laser scanner to scan the tunneling section in real time, comparing the obtained actual profile data with the designed profile data; comparing the deviation between the actual profile data and the designed profile data every 1m of tunneling, and when the deviation exceeds ±5cm, the cutting head rotating speed, the advancing speed and the cutting depth are adjusted.

[0067] The above embodiments are only for illustrating the technical concept and characteristics of the present application, and the purpose is to enable those skilled in the art to understand the content of the present application and implement it, and cannot limit the protection scope of the present application. Any equivalent transformation or modification made according to the spirit and essence of the present application shall be covered within the protection scope of the present application.

Claims

1. A tunnel construction method based on a boom-type tunneling machine, characterized by, The method comprises the following steps: S1: installing a sensing system on the boom-type tunneling machine, the sensing system comprising stress sensors arranged around the cutting head, vibration sensors arranged on the boom, displacement sensors arranged at the connection between the cutting head and the boom, and acoustic emission sensors arranged at the front end of the cutting head; The vibration sensors comprise three-direction vibration sensors arranged at the root, middle and end of the boom; S2: collecting the surrounding rock stress data, tunneling machine vibration data, cutting head position data and rock fracture acoustic signal data detected by the sensing system; S3: establishing a parameter optimization model according to the data, and calculating the cutting head rotating speed, advancing speed and cutting depth; The advancing speed V is calculated by the following formula: Wherein, V0 is the reference advancing speed, k1 and k2 are adjustment coefficients, σ is the surrounding rock stress, σmax is the allowable maximum surrounding rock stress, AE is the acoustic emission signal intensity, AEmax is the allowable maximum acoustic emission signal intensity, and θ is the rock layer inclination; The cutting depth D is calculated by the following formula: Wherein, D0 is the reference cutting depth, α and β are adjustment coefficients, σ is the surrounding rock stress, σmax is the allowable maximum surrounding rock stress, ρ0 is the standard rock density, ρ is the actual rock density, and h is the surrounding rock grade; S4: construction control of the tunneling machine according to the cutting head rotating speed, advancing speed and cutting depth.

2. A tunnel construction method based on a boom-type tunneling machine according to claim 1, characterized by, The stress sensors are uniformly arranged around the cutting head at 8 positions, and the interval between adjacent stress sensors is 45°.

3. The tunneling method based on the boom-type tunneling machine according to claim 1, characterized by The acoustic emission sensors are arranged in a cross shape at the front end of the cutting head.

4. The tunneling method based on the boom-type tunneling machine according to claim 1, characterized by The cutting head rotating speed n is calculated by the following formula: wherein, n 0 is a reference rotational speed, σ is a surrounding rock stress, σ max is an allowable maximum surrounding rock stress, v is a vibration speed, v max is an allowable maximum vibration speed, d is a displacement deviation, d max is an allowable maximum displacement deviation.

5. The tunneling method based on the boom-type tunneling machine according to claim 1, characterized by Step S4 comprises: when the surrounding rock stress is monitored to exceed 85% of the set threshold, the advancing speed is reduced by 20%; when the vibration amplitude exceeds the warning value, the cutting head rotating speed is adjusted; when the displacement deviation exceeds ±10mm, the trajectory is corrected; and the cutting depth is dynamically adjusted according to the acoustic emission signal intensity.

6. The tunneling method based on the boom-type tunneling machine according to claim 1, characterized by The step S4 further comprises: using a three-dimensional laser scanner to perform real-time scanning on the tunneling section, comparing the obtained actual profile data with the designed profile data; comparing the deviation between the actual profile data and the designed profile data every 1m of tunneling; and when the deviation exceeds ±5cm, adjusting the cutting head rotating speed, advancing speed and cutting depth.

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