Real-time vibration reduction method for subway station based on vibration propagation path

Abstract

The present application relates to the field of urban rail transit vibration reduction, and is a real-time vibration reduction method for subway stations based on vibration propagation paths. The vibration reduction steps include arranging active vibrators and arrayed vibration sensors; when a vehicle passes through the station, vertical vibration generated by the train and track system propagates along the middle column to the top beam, serving as a vibration source; the arrayed vibration sensors monitor the vibration source at the corresponding position; the electronic control hub preliminarily analyzes the vibration data obtained by the arrayed vibration sensors to determine whether the vibration peak intensity exceeds a threshold value; if the threshold value is exceeded, step four is entered, and if the threshold value is not exceeded, the monitoring ends; if the threshold value is exceeded, the real-time counter-vibration amplitude is determined; and the active vibrators on the top beam and middle column perform counter-vibration. The method provided by the present application effectively reduces the disturbance of train vibration on the upper buildings and reduces the environmental noise problem caused by train vibration during operation.

Description

Technical Field

[0001] This invention relates to the field of vibration reduction in urban rail transit, and is a real-time vibration reduction method for subway stations based on vibration propagation paths. Background Technology

[0002] In recent years, with the development of large-scale urban rail transit and infrastructure projects in my country, new problems such as urban vibration and noise have emerged one after another, placing more stringent standards on the urban environment, especially at night when the response to vibration is more sensitive. The sources of vibration are usually threefold: random excitation, such as wheel-rail unevenness; periodic excitation sources, such as wheelset misalignment; and vibration caused by collisions between train wheelsets and wheelsets or turnouts.

[0003] The main hazards of vibrations generated by rail transit are: adverse impacts on the structural safety of surrounding buildings, damage to protected cultural relics within specific buildings, and secondary structural noise caused by vibration propagation, which is extremely detrimental to the physical and mental health of residents. Studies show that the amplitude of vibrations does not increase or decrease unidirectionally with building height, but rather varies as a linear cosine function, with the variation range mostly concentrated in the low-frequency band. While vibrations may not cause destructive effects on the building itself in the short term, they are easily felt by people, disturbing the rest of nearby residents and affecting their daily routines.

[0004] Currently, there are no active vibration reduction measures directly targeting urban rail transit vibrations; most are passive vibration reduction measures. These include installing vibration isolation structures at the vibration source, specifically track vibration damping fasteners, rubber floating slabs or steel spring floating slabs, and integral track bed vibration damping structures. For vibration reduction near stations, common measures include installing barriers, drainage ditches, and filled trenches, or installing foundation vibration isolation within buildings. Summary of the Invention

[0005] The purpose of this method is to develop an active measure to overcome the shortcomings of existing measures. Specifically, it provides an immediate measure whereby, when vibration propagates upwards from the bottom of the station along the station structure, the corresponding active vibrators in the central columns, main beams, and roof slab will generate corresponding reverse vibrations. This balances the two phases, achieving active vibration reduction and preventing vibrations generated during subway train operation from disturbing the superstructure.

[0006] The objective of this invention can be achieved through the following technical solutions:

[0007] The present invention describes a real-time vibration reduction method for subway stations based on vibration propagation path. This vibration reduction method is based on an active vibrator, which is controlled by an electronic control hub. The electronic control hub acquires vibration signals from an array of vibration sensors.

[0008] The vibration reduction steps are as follows:

[0009] Step 1: Install active vibrators at the top of each central column of the station, and install active vibrators on the upper surface of the main beam; install array-type vibration sensors on the inner top surface of the main beam and the side walls of the mounting bases of the main beam and the central column.

[0010] Step 2: When the vehicle passes through the station, the vertical vibration generated by the train and track system propagates along the central column of the station to the top beam, which is the vibration source; array-type vibration sensors monitor the vibration source at the corresponding location;

[0011] Step 3: The electronic control hub performs preliminary analysis on the vibration data acquired by the array vibration sensors to determine whether the peak vibration intensity exceeds the threshold. If it exceeds the threshold, proceed to Step 4; otherwise, the monitoring ends.

[0012] Step 4: If the threshold is exceeded, remove or reduce interference noise from the original signal, extract key signal information, and determine the real-time anti-vibration amplitude.

[0013] Step 5: The active vibrators on the main beam and the central column vibrate in the opposite direction.

[0014] The real-time vibration reduction method for subway stations based on vibration propagation path described in this invention, after the array vibration sensor measures the vertical vibration, uses this index as input to obtain the following expression for the amplitude-frequency characteristic function:

[0015]

[0016] In the formula, H(jω) is the final output frequency value, Y(jω) is the Fourier transform of the sensor response signal, X(jω) is the Fourier transform of the vibration source excitation signal, j represents the imaginary unit, and ω represents the angular frequency of the vibration source signal. n ξ represents the angular frequency of the sensor signal, and ξ is the damping.

[0017] The damping of the vibration sensor should preferably be within a specific range, ξ = 0.65 to 0.7, ω / ω n =0 to 0.4.

[0018] The real-time vibration reduction method for subway stations based on vibration propagation path described in this invention includes an electronic control hub comprising a vibration data preprocessing component and a vibration active control component. The vibration data preprocessing component performs preliminary analysis on the digital signals acquired by the array-type vibration sensor. The vibration data preprocessing component amplifies the output voltage in the array-type vibration sensor for analog-to-digital conversion.

[0019] In the vibration data preprocessing component, the voltage amplification factor Satisfying one step size adjustment, where U out U is the change in output current. in This refers to the change in input current.

[0020] The ratio of the output current amplitude to the input current amplitude of the vibration active control component changes linearly, as expressed in the following formula:

[0021]

[0022] A(ω) is the ratio of the output current amplitude to the input current amplitude in the resting state. The ratio of the output current amplitude to the input current amplitude under operating conditions, where ω is the angular frequency. c t0 is the angular frequency in the resting state, and t0 is the original signal period of the vibration active control component;

[0023] The active vibrator in the central column and the active vibrator on the main beam receive commands from the active vibration control component. When the vibration signal exceeds the threshold, they generate vibrations with the same frequency but opposite direction as the vibration to be eliminated, so that they overlap with the vertically propagating vibration for a certain period of time to reduce the vibration of the central column and the main beam.

[0024] The real-time vibration reduction method for subway stations based on vibration propagation path described in this invention uses an electromagnetic vibration table as the active vibrator, and the maximum acceleration of the electromagnetic vibration table is: a = 0.002 × f × D

[0025] In the formula, f is the vibration frequency and D is the amplitude; the maximum amplitude of the electromagnetic vibration table is 20 / 0.02f, and the theoretical maximum amplitude is 5mm.

[0026] The real-time vibration reduction method for subway stations based on vibration propagation path described in this invention has a ratio of 10:1 for the number of active oscillators.

[0027] Beneficial effects:

[0028] Compared with existing technologies, the method provided by this invention actively reduces vibration along the vibration propagation path. Active vibrators are respectively installed at the top of the central column, both sides of the main beam, and the bottom of the top slab. When vibration propagates upward along the central column, main beam, and top slab, the corresponding active vibrators generate opposite vibrations, achieving the purpose of canceling vibrations within the substructure and further reducing upward vibration propagation. Therefore, the practical effects of this invention are: effectively reducing the intrusion of train vibrations into the superstructure; and reducing environmental noise problems caused by train vibrations during operation. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the layout of a real-time vibration reduction device for subway stations based on the vibration propagation path according to the present invention.

[0030] Figure 2 This is an enlarged schematic diagram of the station structure of the present invention;

[0031] Figure 3 This is a schematic diagram illustrating the working principle of the real-time vibration reduction method for subway stations based on the vibration propagation path of this invention.

[0032] Among them, 1-1 is the top plate array vibration sensor; 1-2 is the main beam array vibration sensor; 1-3 is the middle column array vibration sensor; 2-1 is the top plate active vibrator; 2-2 is the main beam active vibrator; 2-3 is the middle column active vibrator. Detailed Implementation

[0033] To make the objectives and technical solutions of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0034] like Figure 1 As shown: The present invention provides a real-time vibration reduction method for subway stations based on vibration propagation path. The method uses an active vibrator to reduce vibration. The active vibrator is controlled by an electronic control hub, which acquires vibration signals from an array of vibration sensors.

[0035] The active vibrator of the top plate is located at the center of the top plate; the active vibrator of the main beam is located in the middle of the main beam; the active vibrator of the middle column is located at the top of the middle column; array-type sensors are arranged on the top plate, the main beam and the middle column, namely, array-type vibration sensor 1-1 for the top plate, array-type vibration sensor 1-2 for the main beam and array-type vibration sensor 1-3 for the middle column.

[0036] The top plate array vibration sensor 1-1 is arranged horizontally at 1m intervals below the top plate; the middle column array vibration sensor 1-3 is arranged longitudinally at 1m intervals on both sides of the top beam above the middle column; the main beam array vibration sensor 1-2 is arranged horizontally at 1m intervals on both sides of the main beam; the ratio of the number of active vibrators to the number of active vibrators is 10:1.

[0037] The vibration reduction method of the present invention has the following steps:

[0038] Step 1: Install active vibrators at the top of each central column of the station, and install active vibrators on the upper surface of the main beam; install array-type vibration sensors on the inner top surface of the main beam and the side walls of the mounting bases of the main beam and the central column.

[0039] Step 2: When the vehicle passes through the station, the vertical vibration generated by the train and track system propagates along the central column of the station to the top beam, which is the vibration source; array-type vibration sensors monitor the vibration source at the corresponding location;

[0040] Step 3: The electronic control hub performs preliminary analysis on the vibration data acquired by the array vibration sensors to determine the magnitude of the vibration peak intensity and whether it exceeds the threshold. If it exceeds the threshold, proceed to Step 4; otherwise, the monitoring ends.

[0041] Step 4: If the threshold is exceeded, remove or reduce interference noise from the original signal, extract key signal information, and determine the real-time anti-vibration amplitude.

[0042] Step 5: The active vibrators on the main beam and the central column vibrate in the opposite direction.

[0043] The electronic control hub consists of a vibration data preprocessing component and a vibration active control component;

[0044] The vibration data preprocessing component performs preliminary analysis on the digital signal to determine the magnitude of the vibration peak intensity and whether it exceeds the threshold.

[0045] The active vibration control component performs post-processing on the digital signal, removing or reducing interference noise from the original signal and extracting key signal information. It determines the real-time anti-vibration amplitude and sends anti-vibration commands to the active vibrator 2-1 of the top slab, the active vibrator 2-2 of the main beam, and the active vibrator 2-3 of the middle column.

[0046] Active vibrator 2-1; main beam active vibrator 2-2; and central column active vibrator 2-3 receive commands from the active vibration control component to induce reverse vibrations at positions such as the central column, main beam, and top plate. Vertical vibrations generated by the train-track system propagate upwards and serve as the vibration source. Vibration sensors monitor the vertical vibrations at the corresponding locations.

[0047] This vibration sensor converts the vibration parameters of the subway station structure into electrical signals, which are then input into a preprocessing circuit. A modulation circuit improves the signal-to-noise ratio. When the vibration sensor receives vibrations from the top slab, main beam, and central column, it generates an inertial force opposite to the vibration direction, causing proportional deformation. This deformation is sensed by a diffusion resistor attached internally. Based on this, the change in resistance causes a change in the output voltage, thus achieving the purpose of measuring vertical vibration acceleration.

[0048] An array-type vibration sensor comprises multiple vibration sensors that convert structural vibrations into digital signals, which are then transmitted to an electronic control hub. The electronic control hub consists of a vibration data preprocessing component and an active vibration control component. The vibration data preprocessing component performs preliminary analysis of the digital signals, determining the peak vibration intensity and whether it exceeds a threshold. The active vibration control component performs post-processing of the digital signals, removing or reducing interference noise from the original signals and extracting key signal information. Real-time anti-vibration amplitude is determined, and anti-vibration commands are sent to active vibrators 2-1, 2-2 (main beam), and 2-3 (middle column). These active vibrators receive commands from the active vibration control component. During the upward propagation of vibration, the path can be summarized as two paths: from the middle column to the main beam, and from the side wall to the top slab. Corresponding anti-vibration devices are installed during the propagation process to reduce the vibration continuing to propagate upwards at the corresponding locations, achieving vibration reduction.

[0049] After measuring the vertical acceleration, the vibration sensor can be used as input to derive its amplitude-frequency response function.

[0050]

[0051] The damping of the vibration sensor should be within a specific range, ξ = 0.65–0.7, ω / ω n =0~0.4, measurable range It can meet the measurement requirements within the station's vibration frequency range, with a measurement error of less than 0.5%. If the damping is too low, it cannot effectively control the sensor's free vibration in the initial stage of vibration, which will indirectly have an adverse effect on the acceleration measurement.

[0052] The vibration data preprocessing component amplifies the output voltage from the vibration sensor for analog-to-digital conversion.

[0053] The vibration data preprocessing component mainly involves discrete sampling, amplitude quantization, and encoding of vibration parameters. First, a specific sampling interval is selected, ensuring that the sampled signal is discontinuous in the time domain but continuous in amplitude. Second, the quantization encoder converts the amplitude of each sampled signal into a digital code. Finally, the sampled vibration signal is converted into a digital sequence. The sampling process can then determine whether a threshold is exceeded, and subsequently issue an anti-vibration command.

[0054] In the vibration data preprocessing component, the signal is amplified at the front end of the data module. Assume the amplification factor is 2. x Then the output voltage amplification increment is It satisfies the step size adjustment once.

[0055] The ratio of the output amplitude to the input amplitude of the vibration active control component changes linearly, which can be expressed as:

[0056]

[0057] Active vibrator 2-1; main beam active vibrator 2-2; middle column active vibrator 2-3 receive commands from the active vibration control component. When the vibration signal exceeds the threshold, it generates vibration with the same frequency and opposite direction as the vibration to be eliminated, so that it overlaps with the vertically propagating vibration for a certain period of time, thereby achieving the purpose of active vibration reduction.

[0058] The active oscillator uses an electromagnetic vibration table, which utilizes electromagnetic excitation to induce longitudinal vibrations with increasing and decreasing amplitude. The maximum acceleration of the electromagnetic vibration table is a = 0.002 × f × D, which is positively correlated with frequency and amplitude, and theoretically has a maximum acceleration of 20g. The maximum amplitude of the electromagnetic vibration table is 20 / 0.02f, and theoretically has a maximum amplitude of 5mm.

[0059] Example 1:

[0060] Main beam (top) dimensions: 1000mm×1800mm (width×height), central column dimension Φ1600mm, top plate thickness 700mm, all using C40 concrete.

[0061] An electromagnetic vibration table is positioned at the center of the top of the central column, with a rectangular space of 150mm × 250mm × 200mm reserved before the main beam is poured. To ensure stability, the vibration table is fixed with four feet, ensuring the bottom plane is horizontal and the centerline coincides with the center of the central column to guarantee vertical vibration transmission and meet amplitude requirements. Wiring holes are provided to ensure connection to the external power supply, sensors, and central control components. Simultaneously, steel plates are welded to the outside of the central column, with vibration sensors vertically mounted on them. The sensors are fixed using magnetic disks, with magnetic chucks at their bottoms that directly adhere to the steel plates, ensuring sensor stability. The welding points are located at four points radially and vertically along the central column; the average value of these four points is used as the input signal during measurement.

[0062] The electromagnetic vibration table is positioned at the middle and both ends of the main beam, with a rectangular space of 150mm × 250mm × 200mm reserved before the top slab is poured. To ensure stability, the vibration table is fixed with four feet, ensuring the bottom plane is horizontal and the centerline coincides with the vertical direction of the main beam to guarantee vertical vibration transmission and meet amplitude requirements. Wiring holes are provided to ensure connection to the external power supply, sensors, and central control components. A groove is also provided on the top of the main beam, containing a steel plate on which the vibration sensor is vertically placed. The sensor is fixed with a magnetic disk, and its bottom is equipped with a magnetic chuck. The chuck directly adheres to the steel plate, ensuring sensor stability. The groove is located at four points 500mm radially and vertically from the center of the vibration table; the average value of these four points is used as the input signal during measurement.

[0063] The electromagnetic vibration table is positioned above the top plate and is secured with four feet to ensure stability. The bottom plane must be horizontal, and the centerline must coincide with the centerline of the central column to ensure vertical vibration transmission and meet the required amplitude specifications. Wiring holes are provided to ensure connection to the external power supply, sensors, and central control components. A recessed groove is provided at the top of the top plate, containing an iron plate on which the vibration sensor is vertically placed. The sensor is fixed using a magnetic disk, with a magnetic chuck at its bottom. The chuck directly adheres to the steel plate, ensuring sensor stability. The groove is located at four points 500mm radially and vertically from the center of the vibration table. During measurement, the average value of these four points is used as the input signal.

[0064] The output voltage amplification circuit primarily employs various series amplification and voltage boosting techniques. The front end of the circuit consists of two symmetrical, identical miniature voltage double harmonic enhancement circuits, exhibiting a two-stage series amplification. This allows the input structural vibration signal to be directly applied to the front end of the circuit, effectively reducing external resonant interference and simultaneously improving the output impedance. The rear-end circuit is a differential amplifier circuit, which both blocks the propagation of the resonant signal and converts the two signals into a single output to meet the output voltage requirements.

[0065] 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, and improvements 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 vibration reduction method for subway stations based on vibration propagation path, characterized in that: This vibration reduction method is based on an active oscillator, which is controlled by an electronic control hub. The electronic control hub acquires vibration signals from an array of vibration sensors. The vibration reduction steps are as follows: Step 1: Install active vibrators at the top of each central column of the station, and install active vibrators on the upper surface of the main beam; install array-type vibration sensors on the inner top surface of the main beam and the side walls of the mounting bases of the main beam and the central column. Step 2: When the vehicle passes through the station, the vertical vibration generated by the train and track system propagates along the central column of the station to the top beam, which is the vibration source; array-type vibration sensors monitor the vibration source at the corresponding location; Step 3: The electronic control hub performs preliminary analysis on the vibration data acquired by the array vibration sensors to determine whether the peak vibration intensity exceeds the threshold. If the threshold is exceeded, proceed to step four; otherwise, monitoring ends. Step 4: If the threshold is exceeded, remove or reduce interference noise from the original signal, extract key signal information, and determine the real-time anti-vibration amplitude. Step 5: The active vibrators on the main beam and the central column vibrate in the opposite direction.

2. The real-time vibration reduction method for subway stations based on vibration propagation path according to claim 1, characterized in that: After measuring the vertical vibration, the array-type vibration sensor uses this index as input to obtain the following expression for the amplitude-frequency characteristic function: In the formula, H(jω) is the final output frequency value, Y(jω) is the Fourier transform of the sensor response signal, X(jω) is the Fourier transform of the vibration source excitation signal, j represents the imaginary unit, ω represents the angular frequency of the vibration source signal, and ω n ξ represents the angular frequency of the sensor signal, and ξ is the damping. The damping of the vibration sensor should preferably be within a specific range, ξ = 0.65~0.7, ω / ω n =0 to 0.

4.

3. The real-time vibration reduction method for subway stations based on vibration propagation path according to claim 1, characterized in that: The electronic control hub includes a vibration data preprocessing component and a vibration active control component; the vibration data preprocessing component performs preliminary analysis on the digital signals acquired by the array vibration sensor; the vibration data preprocessing component amplifies the output voltage in the array vibration sensor for analog-to-digital conversion; In the vibration data preprocessing component, the voltage amplification factor To satisfy one step size adjustment, where U out U is the change in output current. in This refers to the change in input current. The ratio of the output current amplitude to the input current amplitude of the vibration active control component changes linearly, as expressed in the following formula: A(ω) is the ratio of the output current amplitude to the input current amplitude in the resting state, φ(ω) is the ratio of the output current amplitude to the input current amplitude in the operating state, and ω is the angular frequency. c t0 is the angular frequency in the resting state, and t0 is the original signal period of the vibration active control component; The active vibrator in the central column and the active vibrator on the main beam receive commands from the active vibration control component. When the vibration signal exceeds the threshold, they generate vibrations with the same frequency but opposite direction as the vibration to be eliminated, so that they overlap with the vertically propagating vibration for a certain period of time to reduce the vibration of the central column and the main beam.

4. The real-time vibration reduction method for subway stations based on vibration propagation path according to claim 1, characterized in that: The active oscillator is an electromagnetic vibration table, and the maximum acceleration of the electromagnetic vibration table is: a = 0.002 × f × D In the formula, f is the vibration frequency and D is the amplitude.

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