An underground pipe gallery self-adaptive damping support and a regulation method thereof

Abstract

This invention discloses an adaptive vibration damping support for underground utility tunnels and its control method. The support includes: a foundation support structure, a pipe structure support component, a vibration damping component, a vibration monitoring component, and an air pressure regulating component. The vibration damping component includes a rubber vibration damping unit and an air spring unit. The rubber vibration damping unit is disposed between the pipe and the pipe structure support component to attenuate mid-to-high frequency vibrations. The air spring unit is disposed between the pipe structure support component and the foundation support structure to isolate mid-to-low frequency vibrations. Under the premise of meeting the load-bearing capacity constraints of the air spring unit and reducing the risk of resonance, the optimal air pressure of the air spring unit is determined based on the comprehensive evaluation results of the vibration response frequency and vibration response amplitude of the vibration damping support, so as to achieve coordinated attenuation of vibrations in different frequency bands, while simultaneously isolating high-frequency and mid-to-low frequency vibrations, thereby improving the overall vibration damping performance.

Description

Technical Field

[0001] This invention relates to the field of vibration control technology for urban underground utility tunnels, specifically to an adaptive vibration damping support and its control method for the integrated development of rail transit and underground utility tunnels, which is applicable to vibration reduction and safety protection of the internal pipeline system of the integrated utility tunnel under the vibration conditions of subway operation. Background Technology

[0002] In the integrated development of rail transit and underground utility tunnels, the vibrations generated by train operation are continuously transmitted to the pipeline system through the track structure, surrounding soil, and tunnel structure. Subway operation vibrations are characterized by periodicity, continuity, and wide frequency bands. Long-term effects can easily lead to problems such as loosening of pipe (cable) joints, rainwater leakage, gas pipeline leaks, and fatigue damage to the tunnel structure, impacting the safe operation of the underground utility tunnel. Existing vibration reduction measures are mainly designed for short-term strong vibrations such as earthquakes, and differ significantly from subway operation vibrations in terms of frequency characteristics, excitation energy, and duration of action, making them difficult to directly apply to integrated development scenarios of rail transit and underground utility tunnels.

[0003] Existing underground utility tunnel supports mainly include rigid supports, rubber vibration damping supports, spring vibration damping supports, and hydraulic damping supports. Rigid supports have high load-bearing capacity, but vibrations are easily transmitted to the pipeline through rigid connections; rubber vibration damping supports have a certain attenuation effect on medium and high frequency vibrations, but their isolation capacity for medium and low frequency vibrations is limited; ordinary spring vibration damping supports are beneficial for isolating medium and low frequency vibrations, but when stiffness is too low, they are prone to large vibration displacements and may have insufficient load-bearing capacity; hydraulic damping supports have complex structures and high costs. On the other hand, the dynamic parameters of existing supports are usually fixed, making it difficult to adjust them according to geological conditions along the route, the structure of the utility tunnel, train operating conditions, and actual vibration response changes.

[0004] Therefore, it is of great significance to develop a new type of pipe gallery vibration reduction support that is designed for the combined development of rail transit and underground pipe gallery, and has the functions of broadband composite vibration reduction, vibration monitoring and adaptive adjustment. Summary of the Invention

[0005] The purpose of this invention is to address the problems existing in the prior art by providing an adaptive vibration reduction support for underground utility tunnels and its control method.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: Firstly, an adaptive vibration damping support for underground utility tunnels is provided, comprising: Basic support structure for connecting the pipe gallery; Pipeline structure support components are installed on the basic support structure to support and fix the pipelines in the pipe gallery; A vibration damping assembly includes a rubber vibration damping unit and an air spring unit; the rubber vibration damping unit is disposed between the pipe and the pipe structure support assembly to attenuate medium and high frequency vibrations; the air spring unit is disposed between the pipe structure support assembly and the foundation support structure to isolate medium and low frequency vibrations and provide the vertical bearing capacity required by the pipe structure support assembly. A vibration monitoring component is installed on the pipeline structure support component and the pipeline to collect vibration information of the pipeline structure support component (vibration damping bracket, pipe gallery) and / or the pipeline, including at least vibration frequency, vibration amplitude and other parameters that can characterize the vibration state. An air pressure regulating component, connected to the air spring unit, is used to regulate the air pressure inside the air spring unit to change the equivalent stiffness and vibration damping natural frequency of the air spring unit. Under the premise of meeting the load-bearing capacity constraints of the air spring unit and reducing the risk of resonance, the optimal air pressure of the air spring unit is determined based on the comprehensive evaluation results of the vibration response frequency and vibration response amplitude of the vibration damping bracket.

[0007] Furthermore, the air pressure regulating component adopts a manual regulation mode, an automatic regulation mode, or a semi-automatic regulation mode combining manual and automatic regulation; the air pressure regulating component includes at least a pressure regulating pump, which is connected to the air spring unit through a pipeline; in the automatic regulation mode, the pressure regulating pump is also connected to a pressure control module and a data processing module.

[0008] The air pressure regulating component is used to regulate the internal air pressure of the air spring. Specifically, it can be adjusted according to vibration monitoring data, thereby changing the equivalent stiffness of the air spring and the natural frequency of the system to adapt to the differences in working conditions such as geological conditions along the pipeline, the form of the pipe gallery, and changes in subway operating speed, so as to minimize the impact of subway vibration on the pipeline structure along the line.

[0009] Furthermore, in automatic adjustment mode, the vibration monitoring component collects the vibration response of the pipeline and the vibration response of the vibration damping support. The data processing module extracts the vibration response frequency and amplitude of the vibration damping support, and evaluates the comprehensive vibration damping performance of the vibration damping support under candidate air pressure by combining the load state and vibration damping natural frequency of the air spring unit, and controls the pressure regulating pump to perform inflation or deflation. In manual adjustment mode, the operator adjusts the internal air pressure of the air spring unit according to the test results or operating experience. In semi-automatic adjustment mode, a pressure adjustment suggestion is generated, which is then confirmed by the operator and executed.

[0010] Furthermore, the vibration monitoring component includes a first vibration sensor and a second vibration sensor, which are electrically connected to the air pressure regulating component respectively; the first vibration sensor is disposed on the surface of the pipe and is used to collect the vibration response of the pipe; the second vibration sensor is disposed on the surface of the pipe structure support component and is used to collect the vibration response of the pipe structure support component, that is, the vibration effect of the entire support structure, in order to evaluate the vibration reduction effect of the rubber damping unit and the air spring unit.

[0011] Preferably, the first vibration sensor and the second vibration sensor are respectively mounted on the pipe and the pipe structure support assembly using a detachable mounting structure.

[0012] Preferably, the pipe structure support component adopts a ring-shaped structure, and the ring-shaped structure is provided with connecting lugs on both sides; the air spring units are a pair arranged symmetrically, and the output ends of the pair of air spring units are respectively connected to the connecting lugs; the rubber vibration damping unit adopts a hollow structure and is arranged in a ring around the inner circumference of the ring-shaped structure.

[0013] Furthermore, when the internal air pressure of the air spring unit increases, the equivalent stiffness and the vibration damping natural frequency increase accordingly; when the internal air pressure of the air spring unit decreases, the equivalent stiffness and the load-bearing capacity of the vibration damping bracket decrease accordingly.

[0014] Furthermore, the multiple vibration damping brackets are divided into several control sections, and each control section is equipped with one or more vibration monitoring points. The vibration monitoring components are installed at the vibration monitoring points, and the pressure of multiple air spring units in the same control section is adjusted according to the monitoring results of the vibration monitoring components.

[0015] Secondly, a method for controlling an adaptive vibration damping support for underground utility tunnels is provided, comprising the following steps: The initial or candidate air pressure of the air spring unit is set, and the pressure is adjusted by the air pressure regulating component. Obtain the equivalent stiffness of the air spring unit, the load-bearing state of the vibration damping bracket, and the natural frequency of vibration damping under the current air pressure; The vibration monitoring component collects vibration data of the pipeline and vibration damping support, and the vibration response frequency and vibration response amplitude of the vibration damping support are obtained through signal processing. With the goal of reducing the vibration response frequency and amplitude of the vibration damping bracket, and constrained by the requirement that the load-bearing capacity of the air spring unit meets the requirements and the vibration damping natural frequency avoids the vibration excitation frequency range of rail transit, the comprehensive vibration damping performance of the vibration damping bracket under the current air pressure is evaluated, and the comprehensive vibration damping performance evaluation result is obtained. The air pressure of the air spring unit is determined or updated based on the comprehensive vibration reduction performance evaluation results, and pressure adjustment and vibration monitoring are performed again. Repeat the above steps until the vibration response frequency and vibration response amplitude of the vibration damping bracket are optimal, and the air spring unit's load-bearing capacity constraint and resonance risk constraint are satisfied, thus obtaining the optimal air pressure of the air spring unit under the current working condition.

[0016] The control method also includes the steps of theoretical analysis and control of the dynamic characteristics of the vibration damping support: Based on the parameters characterizing the vibration state, a dynamic model of the vibration reduction system is established according to the theory of vibration dynamics. Based on the dynamic model of the vibration reduction system, the dynamic equilibrium equations of the pipe structure support components are established according to Newton's second law; After rearranging the above dynamic equilibrium equations, we obtain the matrix expression of the vibration reduction system, which includes at least the mass matrix, damping matrix, and stiffness matrix. The matrix expression is processed and rearranged to obtain the characteristic equation of the vibration reduction system; The characteristic equation of the vibration reduction system is expanded and rearranged to obtain a fourth-order polynomial for the complex eigenvalues ​​of the vibration reduction system, and the complex eigenvalues ​​of the vibration reduction system are obtained; complex modal characteristics are analyzed based on the complex eigenvalues ​​of the vibration reduction system.

[0017] Compared with the prior art, the beneficial effects of this invention are: 1. The local underground pipe gallery adaptive vibration damping support adopts a composite vibration damping system by combining rubber vibration damping units and air spring units to achieve synergistic attenuation of vibrations in different frequency bands, and can simultaneously achieve high-frequency and mid-to-low-frequency vibration isolation, thereby improving the overall vibration damping performance; 2. Under the premise of meeting the air spring load-bearing capacity constraints and reducing resonance risk, a dual-objective comprehensive evaluation of the support vibration response frequency and support vibration response amplitude is carried out to avoid rigid transmission caused by excessive air pressure and excessive amplitude and insufficient load-bearing capacity caused by excessive air pressure; 3. The air pressure adjustment component is compatible with manual adjustment, automatic adjustment, and... 4. The vibration monitoring components adopt a detachable structure, allowing the monitoring components to be deployed only in important or typical sections of the pipeline. The air spring pressure can be set in other sections with reference to the above-mentioned typical sections, thereby reducing the number of sensors and system maintenance costs. 5. The local underground utility tunnel adaptive vibration reduction support is suitable for pipeline vibration reduction control under the combined development conditions of urban underground utility tunnels and rail transit. Through closed-loop monitoring and optimal air pressure update, the internal air pressure of the air spring can adapt to the changes in rail transit operation status, utility tunnel structure and geological conditions along the line, and has good engineering application prospects. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of an adaptive vibration reduction support for underground utility tunnels according to the present invention; Figure 2 This is a schematic diagram of the adaptive vibration reduction support pipe gallery for the underground integrated pipe gallery of the present invention; Figure 3 This is a flowchart illustrating the comprehensive evaluation of the vibration damping performance of the vibration damping bracket and the optimization of the optimal air pressure for the air spring in this invention. Figure 4 This is a schematic diagram showing the relationship between the internal air pressure of an air spring unit and the vibration response frequency and vibration response amplitude. In the diagram: 1. Basic support structure; 2. Pipeline structure support assembly; 3. Pipeline; 4. Rubber vibration damping unit; 5. Air spring unit; 6. Air pressure regulating assembly; 7. First vibration sensor; 8. Second vibration sensor. Detailed Implementation

[0019] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are merely 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.

[0020] In the description of this invention, it should be noted that the terms "middle", "upper", "lower", "left", "right", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0021] Example 1: A self-adaptive vibration damping support for underground utility tunnels is provided, combined with... Figure 1 and Figure 2 As shown, it includes: Basic support structure 1, used to connect the pipe gallery; Pipeline structure support component 2 is disposed on the basic support structure 1 and is used to support and fix the pipeline 3 in the pipe gallery; The vibration damping assembly includes a rubber vibration damping unit 4 and an air spring unit 5. The rubber vibration damping unit 4 is disposed between the pipe 3 and the pipe structure support assembly 2 to attenuate medium and high frequency vibrations. The air spring unit 5 is disposed between the pipe structure support assembly 2 and the foundation support structure 1 to isolate medium and low frequency vibrations and provide the vertical bearing capacity required by the pipe structure support assembly 2. A vibration monitoring component is installed on the pipe structure support component 2 and the pipe 3 to collect vibration information of the vibration damping bracket (pipe structure support component) and / or the pipe, including at least vibration frequency, vibration amplitude and other parameters that can characterize the vibration state. The air pressure regulating component 6 is connected to the air spring unit 5 and is used to regulate the air pressure inside the air spring unit 5 to change the equivalent stiffness and vibration reduction natural frequency of the air spring unit 5. Under the premise of meeting the load-bearing capacity constraints of the air spring unit 5 and reducing the risk of resonance, the optimal air pressure of the air spring unit 5 is determined based on the comprehensive evaluation results of the vibration response frequency and vibration response amplitude of the vibration damping bracket.

[0022] The local underground utility tunnel adaptive vibration damping support adopts a composite vibration damping system by combining rubber vibration damping unit 4 and air spring unit 5 to achieve synergistic attenuation of vibrations in different frequency bands. It can simultaneously achieve high-frequency and mid-to-low-frequency vibration isolation and improve the overall vibration damping performance. Under the premise of meeting the air spring load-bearing capacity constraints and reducing resonance risk, the vibration response frequency and vibration response amplitude of the support are evaluated in a dual-objective manner to avoid rigid transmission caused by excessive air pressure and excessive amplitude and insufficient load-bearing capacity caused by excessive air pressure.

[0023] The local adaptive vibration damping support for underground utility tunnels is suitable for pipeline vibration control under the combined development conditions of urban underground utility tunnels and rail transit. Through closed-loop monitoring and optimal air pressure updates, the internal air pressure of the air spring can adapt to changes in rail transit operation status, utility tunnel structure, and geological conditions along the line, showing good engineering application prospects.

[0024] When the internal air pressure of the air spring unit 5 is too high, the equivalent stiffness of the air spring is too large, and the connection between the pipeline structure support component 2 and the foundation support structure 1 approaches rigidity. This makes it easier for rail transit vibrations to be transmitted to the pipeline structure support component 2 and the pipeline 3, increasing the vibration response frequency of the pipeline structure support component 2 and reducing its overall vibration reduction performance. When the internal air pressure of the air spring unit 5 is too low, the equivalent stiffness and load-bearing capacity of the air spring are insufficient, increasing the vibration response amplitude of the pipeline structure support component 2, which may lead to excessive displacement, insufficient support height, or decreased operational stability. Therefore, the determination of the internal air pressure of the air spring unit 5 should comprehensively consider the vibration reduction performance of the support, the load-bearing capacity of the air spring, and the system resonance risk. Under the condition of meeting the air spring load-bearing capacity requirements and ensuring that the natural frequency of the vibration reduction system avoids the excitation frequency range of rail transit vibrations, the vibration response frequency and amplitude of the pipeline structure support component 2 are used as evaluation parameters to comprehensively evaluate the overall vibration reduction performance of the support corresponding to different candidate air pressures, thereby determining the optimal air pressure under the current operating conditions. Among them, the air spring load-bearing capacity requirement and resonance risk control serve as constraints for determining the optimal air pressure, while the comprehensive improvement of the support vibration response frequency and support vibration response amplitude serves as the evaluation basis for selecting the optimal air pressure.

[0025] Furthermore, the air pressure regulating component 6 adopts a manual adjustment mode, an automatic adjustment mode, or a semi-automatic adjustment mode combining manual and automatic adjustment; the air pressure regulating component 6 includes at least a pressure regulating pump, which is connected to the air spring unit 5 through a pipeline; in the automatic adjustment mode, the pressure regulating pump is also connected to a pressure control module and a data processing module.

[0026] The pressure regulating component is compatible with multiple pressure regulation modes, including manual, automatic, and semi-automatic adjustment, to meet the needs of different engineering applications.

[0027] Furthermore, in automatic adjustment mode, the vibration monitoring component collects the vibration response of the pipeline and the vibration response of the vibration damping support. The data processing module extracts the vibration response frequency and amplitude of the vibration damping support, and evaluates the comprehensive vibration damping performance of the vibration damping support under candidate air pressure by combining the load state and vibration damping natural frequency of the air spring unit, and controls the pressure regulating pump to perform inflation or deflation. In manual adjustment mode, the operator adjusts the internal air pressure of the air spring unit according to the test results or operating experience. In semi-automatic adjustment mode, a pressure adjustment suggestion is generated, which is then confirmed by the operator and executed.

[0028] Specifically, in manual adjustment mode, the air pressure adjustment component includes one or more of the following: an inflation port, an deflation port, a manual pressure regulating valve, and a pressure reducing valve. Operators can adjust the internal pressure of the air spring based on vibration detection results, operational experience, or maintenance requirements. For example, based on the measured vibration response frequency, amplitude, load-bearing status, and operational and maintenance requirements of the support structure, the internal air pressure of the air spring can be adjusted to achieve the optimal overall vibration reduction performance of the support structure under the current operating conditions.

[0029] In automatic adjustment mode, the air pressure regulating component is an automatic pressure regulating device, including one or more of the following: pressure regulating pump, pressure control module, data processing module, and solenoid valve; after the vibration monitoring component collects vibration data, the data processing module extracts the vibration response frequency and vibration response amplitude, and evaluates the comprehensive vibration reduction performance of the support under the candidate air pressure by combining the air spring unit load state and the natural frequency of the vibration reduction system, and then controls the pressure regulating device to perform inflation or deflation.

[0030] In semi-automatic adjustment mode, after the vibration monitoring component collects vibration data, the staff manually calculates or queries the target pressure value and performs pressure adjustment operation, realizing a semi-automatic pressure adjustment mode that combines manual and automatic operation.

[0031] Preferably, the change in air pressure inside the air spring unit 5 can alter the equivalent stiffness of the air spring, the load-bearing capacity of the support, and the natural frequency of vibration reduction. When the air pressure is too high, the vibration response frequency increases; when the air pressure is too low, the vibration response amplitude increases and the load-bearing capacity may be insufficient. The optimal air pressure is determined based on a comprehensive evaluation of the vibration response frequency and amplitude, while meeting the load-bearing capacity constraints and reducing the risk of resonance.

[0032] Furthermore, the vibration monitoring component includes a first vibration sensor 7 and a second vibration sensor 8, which are electrically connected to the air pressure regulating component 6 respectively; the first vibration sensor 7 is disposed on the surface of the pipe 3 and is used to collect the pipe vibration response; the second vibration sensor 8 is disposed on the surface of the pipe structure support component 2 and is used to collect the support structure vibration response to evaluate the vibration reduction effect of the rubber damping unit 4 and the air spring unit 5.

[0033] Preferably, the first vibration sensor 7 and the second vibration sensor 8 are respectively installed on the pipeline and the pipeline structure support assembly with a detachable installation structure, and can be installed, replaced or removed according to monitoring needs.

[0034] The detachable structure allows monitoring components to be deployed only in important or typical sections of the pipeline, while airbag pressure can be set in other sections in accordance with the above-mentioned typical sections, thereby reducing the number of sensors and system maintenance costs.

[0035] Preferably, the pipe structure support component 2 adopts a ring-shaped structure, and the ring-shaped structure is provided with connecting lugs on both sides; the air spring units 5 are a pair arranged symmetrically, and the output ends of the pair of air spring units 5 are respectively connected to the connecting lugs; the rubber vibration damping unit 4 adopts a hollow structure and is arranged in a ring around the inner circumference of the ring-shaped structure. A single-layer rubber structure or a double-layer rubber structure can be selected according to the vibration damping requirements to improve the elastic deformation capacity of the rubber and reduce the vibration transmission efficiency.

[0036] Furthermore, the multiple vibration damping brackets are divided into several control sections, and each control section is equipped with one or more vibration monitoring points. The vibration monitoring components are installed at the vibration monitoring points, and the pressure of multiple air spring units in the same control section is adjusted and optimized based on the monitoring results of the vibration monitoring components.

[0037] In some implementations, a typical section monitoring and coordinated pressure regulation strategy can be adopted. By deploying a small number of vibration monitoring components in typical local sections, the air pressure of the air springs in the same section of the support can be uniformly adjusted based on the vibration characteristic analysis results. This strategy can significantly reduce the number of sensors and lower the system deployment and maintenance costs while ensuring vibration reduction.

[0038] When the vibration response difference between different monitoring points within a typical monitoring section exceeds the preset range, the monitoring section range can be appropriately reduced to improve control accuracy; when the vibration response of multiple adjacent locations tends to be consistent, the typical monitoring range can be appropriately expanded to reduce the total number of vibration monitoring points and improve economy.

[0039] Example 2: A method for controlling an adaptive vibration damping support for underground utility tunnels.

[0040] Combination Figure 2 and Figure 3 As shown, the control method includes the following steps: Step 1: Set the initial air pressure or candidate air pressure of the air spring unit 5, and perform pressure adjustment through the air pressure regulating component 6; Step 2: Obtain the equivalent stiffness of the air spring unit 5, the load-bearing state of the vibration damping bracket, and the natural frequency of vibration damping under the current air pressure; Step 3: Collect vibration data of the pipeline and pipeline structure support component 2 through the vibration monitoring component, and obtain the vibration response frequency and vibration response amplitude of the pipeline structure support component 2 through signal processing; Step 4: With the goal of reducing the vibration response frequency and vibration response amplitude of the pipeline structure support component 2, and with the constraints that the bearing capacity of the air spring unit 5 meets the requirements and the vibration reduction natural frequency avoids the vibration excitation frequency range of rail transit, the comprehensive vibration reduction performance of the vibration reduction bracket under the current air pressure is evaluated, and the comprehensive vibration reduction performance evaluation result is obtained. Step 5: Determine or update the air pressure of the air spring unit 5 based on the comprehensive vibration reduction performance evaluation results, and perform pressure adjustment and vibration monitoring again; Step 6: Repeat steps 2-5 above until the combined vibration response frequency and vibration response amplitude of the pipeline structure support component 2 are optimal, and the bearing capacity constraint and resonance risk constraint of the air spring unit 5 are satisfied, thus obtaining the optimal air pressure of the air spring unit 5 under the current working condition.

[0041] This control method aims to improve both the vibration response frequency and amplitude of the support structure. It is constrained by ensuring that the air spring unit's load-bearing capacity meets the requirements and that the vibration reduction natural frequency avoids the vibration excitation frequency range of rail transit. The optimal air pressure is determined by this constraint. If the current air pressure does not meet the preset vibration reduction requirements, the optimal air pressure is updated and adjusted and monitored again until the optimal air pressure suitable for the current working conditions is obtained.

[0042] like Figure 4As shown, the relationship between the internal air pressure of the air spring unit and the vibration response of the support is nonlinear. When the air pressure is too low, the equivalent stiffness and load-bearing capacity of the air spring are insufficient, the vibration response amplitude of the support is large, and excessive displacement may occur; when the air pressure is too high, the equivalent stiffness of the air spring is too large, the support approaches a rigid connection, and the vibration response frequency of the support is high. Therefore, the internal air pressure of the air spring should not be too high or too low. Figure 4 Popt in the text represents the optimal air spring pressure under the current working conditions. The optimal air spring pressure is determined based on the comprehensive evaluation results of the support vibration response frequency and the support vibration response amplitude, under the condition of meeting the load-bearing capacity requirements and reducing the risk of resonance.

[0043] Example 3: A method for analyzing and controlling the dynamic characteristics of the adaptive vibration reduction support for underground utility tunnels as described in Examples 1 and 2 is provided.

[0044] To analyze the dynamic characteristics of the adaptive vibration damping bracket of this invention and the influence of air spring pressure adjustment on vibration damping performance, a dynamic model of the vibration damping system is established based on the parameters characterizing the vibration state and the theory of vibration dynamics. In the model, the equivalent mass of the pipeline is denoted as... The equivalent mass of the pipeline structure support components is denoted as... The rubber damping unit and the air spring unit are characterized using an equivalent spring-damping model, where the equivalent stiffness and damping of the rubber damping unit are denoted as follows: and The equivalent stiffness and damping of the air spring unit are denoted as follows: and The pipe displacement is The displacement of the pipeline structure support components is .

[0045] The pipeline is mainly subjected to the elastic restoring force and damping force provided by the rubber vibration damping unit. The relative displacement of the rubber vibration damping unit is: The relative velocity is: Based on the dynamic model of the vibration reduction system, the dynamic equilibrium equations of the pipe structure support components are established according to Newton's second law: , In the formula: For the inertial force of the pipeline, For the damping force of the rubber vibration damping unit, This refers to the restoring force of the rubber vibration damping unit.

[0046] The pipeline structure support assembly is simultaneously subjected to the action of the upper rubber damping unit and the lower air spring unit. According to Newton's second law, the dynamic equilibrium equation of the pipeline structure support assembly can be established as follows: , In the formula: For the inertial force of the structural support components, For the damping force of the rubber vibration damping unit, For the restoring force of the rubber vibration damping unit, The damping force of the air spring. This refers to the restoring force of the air spring.

[0047] After rearranging the above dynamic equilibrium equations, we obtain the matrix expression for the vibration reduction system, which includes at least the mass matrix, damping matrix, and stiffness matrix, as follows: , The displacement vector of the vibration reduction system is: , The quality matrix is: , The damping matrix is: , The stiffness matrix is: .

[0048] To analyze the damped vibration characteristics of the vibration reduction system, it is assumed that the system response follows an exponential form: , In the formula: The mode shape vector of the vibration reduction system; For the complex eigenvalues ​​of the vibration reduction system.

[0049] Taking the first and second derivatives of the above expression: , , Substituting into the free vibration equation of the vibration reduction system, we get: , because This can be reduced to a standard eigenvalue problem. , To ensure that the vibration reduction system has a non-zero vibration mode solution, the following must be satisfied: , Substituting the mass matrix and stiffness matrix of the vibration reduction system, we can obtain: , Further processing and simplification of the matrix expression yields the characteristic equation of the vibration reduction system: , Expanding and rearranging the characteristic equation of the vibration reduction system, we obtain a fourth-order polynomial for the complex eigenvalues ​​of the vibration reduction system: , Obtain the complex eigenvalues ​​of the vibration reduction system: , In the formula: The damping ratio; It is the undamped natural frequency; The damped natural frequency.

[0050] The damped natural frequency satisfies: .

[0051] As can be seen from the above relationships, the damping of the vibration reduction system, the equivalent stiffness of the air spring, and the material parameters of the rubber damping unit all affect the dynamic characteristics of the vibration reduction system. When the damping of the vibration reduction system increases, the vibration decay rate of the vibration reduction system increases; when the air pressure of the air spring changes, the equivalent stiffness of the air spring... Changes in the material parameters of the rubber damping unit lead to changes in the system's natural frequency. When the material parameters of the rubber damping unit change, both the system's damping matrix and stiffness matrix will change accordingly, thus affecting the overall dynamic response of the damping system. Furthermore, complex modal analysis reveals that the first mode of the damping system mainly exhibits overall low-to-mid-frequency vibration, and its dynamic characteristics are primarily influenced by the air spring unit; the second mode mainly exhibits localized high-frequency vibration, and its dynamic characteristics are primarily influenced by the rubber damping unit.

[0052] This invention achieves graded isolation of vibrations in different frequency bands through the synergistic effect of air spring units and rubber damping units. The air spring units primarily reduce mid-to-low frequency vibration response, while the rubber damping units primarily attenuate high-frequency vibration energy, thus forming a broadband composite vibration reduction system.

[0053] Adjusting the internal air pressure of the air spring unit can change its equivalent stiffness and the natural frequency of the vibration damping system. When the air pressure increases, the equivalent stiffness of the air spring and the natural frequency of the vibration damping system generally increase, the support approaches a rigid connection, the transmission of rail transit vibration increases, and the vibration response frequency of the support is higher. When the air pressure decreases, the equivalent stiffness of the air spring and the natural frequency of the vibration damping system generally decrease, which is beneficial for isolating higher frequency external excitations. However, when the air pressure is too low, the load-bearing capacity of the support decreases, and the vibration response amplitude and support displacement of the support increase.

[0054] Furthermore, the vibration transmissibility of a vibration reduction system is related to the system's damping ratio and frequency ratio. When the operating frequency of the vibration reduction system enters the effective vibration reduction range, the vibration transmissibility decreases significantly, thereby achieving effective attenuation of vibrations in rail transit (such as subways).

[0055] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An adaptive vibration damping support for underground utility tunnels, characterized in that, include: Basic support structure for connecting the pipe gallery; Pipeline structure support components are installed on the basic support structure to support and fix the pipelines in the pipe gallery; A vibration damping assembly includes a rubber vibration damping unit and an air spring unit; the rubber vibration damping unit is disposed between the pipe and the pipe structure support assembly to attenuate medium and high frequency vibrations; the air spring unit is disposed between the pipe structure support assembly and the foundation support structure to isolate medium and low frequency vibrations and provide the vertical bearing capacity required by the pipe structure support assembly. A vibration monitoring component is installed on the pipeline structure support component and the pipeline to collect vibration information of the pipeline structure support component and / or the pipeline, including at least vibration frequency, vibration amplitude and other parameters that can characterize the vibration state. An air pressure regulating component, connected to the air spring unit, is used to regulate the air pressure inside the air spring unit to change the equivalent stiffness and vibration damping natural frequency of the air spring unit. Under the premise of meeting the load-bearing capacity constraints of the air spring unit and reducing the risk of resonance, the optimal air pressure of the air spring unit is determined based on the comprehensive evaluation results of the vibration response frequency and vibration response amplitude of the vibration damping bracket.

2. The adaptive vibration damping support for underground utility tunnels according to claim 1, characterized in that, The air pressure regulating component adopts a manual adjustment mode, an automatic adjustment mode, or a semi-automatic adjustment mode combining manual and automatic adjustment; the air pressure regulating component includes at least a pressure regulating pump, which is connected to the air spring unit through a pipeline; in the automatic adjustment mode, the pressure regulating pump is also connected to a pressure control module and a data processing module.

3. The adaptive vibration damping support for underground utility tunnels according to claim 2, characterized in that, In automatic adjustment mode, the vibration monitoring component collects the vibration response of the pipeline and the vibration response of the vibration damping support. The data processing module extracts the vibration response frequency and amplitude, and evaluates the comprehensive vibration damping performance of the vibration damping support under the candidate air pressure by combining the load state of the air spring unit and the natural frequency of vibration damping. The module then controls the pressure regulating pump to perform inflation or deflation. In manual adjustment mode, the operator adjusts the internal air pressure of the air spring unit based on the test results or operating experience. In semi-automatic adjustment mode, a pressure adjustment suggestion is generated, which is then confirmed by the operator before the pressure adjustment operation is performed.

4. The adaptive vibration damping support for underground utility tunnels according to claim 1, characterized in that, The vibration monitoring component includes a first vibration sensor and a second vibration sensor, which are electrically connected to the air pressure regulating component respectively. The first vibration sensor is disposed on the surface of the pipe and is used to collect the vibration response of the pipe. The second vibration sensor is disposed on the surface of the pipe structure support component and is used to collect the vibration response of the pipe structure support component to evaluate the vibration reduction effect of the rubber damping unit and the air spring unit.

5. The adaptive vibration damping support for underground utility tunnels according to claim 4, characterized in that, The first vibration sensor and the second vibration sensor are respectively mounted on the pipe and the pipe structure support assembly using a detachable mounting structure.

6. The adaptive vibration damping support for underground utility tunnels according to claim 1, characterized in that, The pipeline structure support component adopts a ring-shaped structure, and the ring-shaped structure is provided with connecting lugs on both sides; the air spring units are a pair arranged symmetrically, and the output ends of the pair of air spring units are respectively connected to the connecting lugs; the rubber vibration damping unit adopts a hollow structure and is arranged in a ring around the inner circumference of the ring-shaped structure.

7. The adaptive vibration damping support for underground utility tunnels according to claim 1, characterized in that, When the internal air pressure of the air spring unit increases, the equivalent stiffness and the vibration damping natural frequency increase accordingly; when the internal air pressure of the air spring unit decreases, the equivalent stiffness and the load-bearing capacity of the vibration damping bracket decrease accordingly.

8. The adaptive vibration damping support for underground utility tunnels according to claim 1, characterized in that, Multiple vibration damping brackets are divided into several control sections. Each control section is equipped with one or more vibration monitoring points. The vibration monitoring components are installed at the vibration monitoring points. The pressure of multiple air spring units in the same control section is adjusted according to the monitoring results of the vibration monitoring components.

9. The method for adjusting the adaptive vibration reduction support for underground utility tunnels according to any one of claims 1 to 8, characterized in that, The control method includes the following steps: The initial or candidate air pressure of the air spring unit is set, and the pressure is adjusted by the air pressure regulating component. Obtain the equivalent stiffness of the air spring unit, the load-bearing state of the vibration damping bracket, and the natural frequency of vibration damping under the current air pressure; The vibration monitoring component collects vibration data of the pipeline and vibration damping support, and the vibration response frequency and vibration response amplitude of the vibration damping support are obtained through signal processing. With the goal of reducing the vibration response frequency and amplitude of the vibration damping bracket, and constrained by the requirement that the load-bearing capacity of the air spring unit meets the requirements and the vibration damping natural frequency avoids the vibration excitation frequency range of rail transit, the comprehensive vibration damping performance of the vibration damping bracket under the current air pressure is evaluated, and the comprehensive vibration damping performance evaluation result is obtained. The air pressure of the air spring unit is determined or updated based on the comprehensive vibration reduction performance evaluation results, and pressure adjustment and vibration monitoring are performed again. Repeat the above steps until the vibration response frequency and vibration response amplitude of the vibration damping bracket are optimal, and the air spring unit's load-bearing capacity constraint and resonance risk constraint are satisfied, thus obtaining the optimal air pressure of the air spring unit under the current working condition.

10. The control method for the adaptive vibration reduction support of underground utility tunnels according to claim 9, characterized in that, It also includes the following steps: Based on the parameters characterizing the vibration state, a dynamic model of the vibration reduction system is established according to the theory of vibration dynamics. Based on the dynamic model of the vibration reduction system, the dynamic equilibrium equations of the pipe structure support components are established according to Newton's second law; After rearranging the above dynamic equilibrium equations, we obtain the matrix expression of the vibration reduction system, which includes at least the mass matrix, damping matrix, and stiffness matrix. The matrix expression is processed and rearranged to obtain the characteristic equation of the vibration reduction system; The characteristic equation of the vibration reduction system is expanded and rearranged to obtain a fourth-order polynomial about the complex eigenvalues ​​of the vibration reduction system, and the complex eigenvalues ​​of the vibration reduction system are obtained. Complex modal characteristics analysis based on complex eigenvalues ​​of vibration reduction systems.

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