448 results about "Vibration attenuation" patented technology

The present invention relates a tunable vibration attenuation device (100) configured to be mounted to a host structure (1) for attenuating vibrations in multiple frequency ranges. The device (100) comprises an auxiliary mass (4) and a shunt piezoelectric system (8) electromechanically coupled between the host structure (1) and the auxiliary mass (4). The shunt piezoelectric system (8) comprising an array of a plurality of piezoelectric devices (2), each connected to at least one shunt circuit (3). Each piezoelectric device (2) being configured to generate electric charge in response to the relative movement of the host structure (1) and the auxiliary mass (4), wherein part of the electric charge is transmitted to at least one shunt circuit (3) of each piezoelectric device (2), and wherein the electrical characteristics of the shunt circuit (3) are adapted to control the oscillatory characteristics of the corresponding piezoelectric devices (2) in one or more vibration frequency ranges of the host structure (1) so as to tune the vibration attenuation device (100) to suppress the host structure vibrations at the desired frequency ranges.

The invention discloses a quasi-zero stiffness metamaterial vibration reduction mounting structure of an underwater vehicle hydrophone, which belongs to the technical field of underwater vehicles, and comprises an oil seal end cover mounted at the front end of a front fairing of an underwater vehicle, a mounting rack fixed at the front end part of the oil seal end cover, and two quasi-zero stiffness vibration reduction components arranged in front of and behind the mounting rack, the outer side parts of the quasi-zero-stiffness vibration reduction components are connected with the mounting frame, concave parts for clamping the end parts of the hydrophone are formed in the middle parts of the quasi-zero-stiffness vibration reduction components, and a mounting space for arranging the hydrophone is formed between the two quasi-zero-stiffness vibration reduction components; and the two ends of the hydrophone are respectively clamped and clamped in the concave parts of the two quasi-zero stiffness damping components. According to the quasi-zero-stiffness metamaterial damping device, through conformal design, vibration attenuation, structure optimization and energy-saving effects, an efficient, stable and low-noise hydrophone installation solution is provided for an autonomous underwater vehicle, and the performance of the quasi-zero-stiffness metamaterial damping device in underwater detection and signal acquisition is remarkably improved.

The invention relates to the technical field of cable fault diagnosis, and discloses an underground cable fault positioning method and device based on vibration attenuation. The method comprises the following steps: acquiring vibration data of a cable by using a plurality of sensors to form a first time sequence; decomposing the first time sequence into a plurality of intrinsic mode function components by adopting an empirical mode decomposition method; according to each intrinsic mode function component, calculating a plurality of characteristic values of the first time sequence; determining a fault position according to the position data and the characteristic value of each sensor by using a preset vibration positioning model; and matching the characteristic value corresponding to the fault position in a preset database to obtain a fault type corresponding to the fault position. The method improves the efficiency and accuracy of underground cable fault detection, guarantees the operation stability of a power system, and remarkably reduces the economic loss and safety risk caused by fault delay.

The invention relates to the technical field of transformer substations, and particularly discloses a transformer substation channel cover plate data acquisition and intelligent analysis management system and method, and the method comprises the steps: collecting cover plate vibration data and strain data through an acceleration sensor and a resistive strain gauge; vibration direction change, vibration attenuation and cover plate deformation springback time are extracted from acceleration data, the maximum amplitude, the change rate and the strain gradient are extracted from strain data, and the stress deformation characteristics of the cover plate are comprehensively represented; based on the stress deformation and springback characteristics of the cover plate, a damage evaluation model is established by adopting a neural network model, and intelligent judgment of the damage degree of the cover plate is realized; predicting a damage change trend by using a neural network, and calculating a cover plate damage acceleration trend; and according to the damage evaluation result and the damage acceleration trend, calculating the remaining to-be-maintained time of the cover plate, and automatically triggering operation and maintenance early warning when the remaining to-be-maintained time is lower than an early warning threshold value. According to the method, intelligent monitoring, prediction and active operation and maintenance management of the health state of the cover plate can be realized.

The invention belongs to the technical field of blasting vibration prediction, and particularly discloses a blasting vibration speed attenuation law prediction method based on regression analysis, and the method comprises the steps: laying monitoring points in multiple directions around a blasting source, synchronously collecting the geological parameters and mass point peak vibration speed of each point, and constructing a segmented propagation path; a single dominant propagation section is identified based on adjacent monitoring point data, independent influence of specific geological conditions on vibration attenuation is quantified by combining single-factor control regression analysis, decoupling modeling of geological factors and attenuation behaviors is realized, and meanwhile, a double-factor dominant propagation section is identified on the basis of quantizing the independent influence of the single geological conditions. And deducting a known effect through residual analysis to separate out an independent contribution of another geological parameter, and finally integrating a multi-factor influence function to construct a comprehensive attenuation model. Progressive modeling from single-factor decoupling to multi-factor collaboration is achieved, and the precision and physical interpretability of blasting vibration prediction in a complex heterogeneous stratum are remarkably improved.

The invention provides a ballastless track joint performance degradation monitoring method and system, and relates to the technical field of track joint performance monitoring, and the method comprises the steps: knocking a ballastless track plate at a track joint through a force hammer to generate excitation, collecting a vertical vibration acceleration response signal through an acceleration sensor, and synchronously recording the knocking time and static parameters. The vertical vibration acceleration response signal is preprocessed, abnormal pulses and baseline drift are removed, a vibration event sample is formed, and joint mechanics characteristic parameters including a vibration frequency parameter reflecting rigidity degradation and a vibration attenuation parameter reflecting damping are extracted. According to the method, the joint performance evaluation index is calculated in combination with the static parameters, the degradation grade is evaluated after the evaluation index is compared with the preset threshold value, an early warning signal is triggered, the joint degradation grade and position information are provided, and monitoring and evaluation of the joint performance are achieved.

The invention relates to sea and air three-dimensional unmanned rescue equipment which comprises a large-load unmanned aerial vehicle platform, a sea life rescue platform, a suspension assembly and a flexible buoyancy platform which are connected in sequence. The heavy-load unmanned aerial vehicle platform is fixed to the upper portion of the offshore life rescue platform in a rigid connection mode. The suspension assembly comprises a main ship body and a multi-body buffer structure connected with the main ship body and the flexible buoyancy platform. The multi-body buffering structure comprises a front arch, a first rear arch, a second rear arch, a first rigid sliding plate, a second rigid sliding plate, a first rocker arm type spring damping vibration attenuation module and a second rocker arm type spring damping vibration attenuation module. The first rigid sliding plate and the second rigid sliding plate are connected with the flexible buoyancy platform. Compared with the prior art, cooperation of safe take-off and landing from a mother ship, hovering search, high sea condition stable operation and flexible rescue is achieved through the four-module integrated design; rescue equipment can be quickly replaced, diversified rescue requirements are met, operation is flexible, and taking-off and landing are safe and convenient.

The invention provides an innovative design of a corrugated pipe damper integrated on a sliding main bearing aiming at the problems of transmission system abrasion and fatigue damage caused by vibration energy accumulation of the wind power main bearing under a complex wind load, and belongs to the technical field of wind power generation equipment. A traditional main bearing damping structure is low in energy absorption efficiency, insufficient in dynamic response and difficult to effectively suppress vibration. Through collaborative design of a corrugated pipe multi-stage laminated structure and a fluid energy dissipation channel, a composite mechanism for dynamically dissipating vibration energy is formed. The core of the damping device is composed of a corrugated pipe assembly, damping cavities and a main shaft adaptive structure, impact energy is absorbed through axial flexible deformation of the corrugated pipe, vibration attenuation is achieved in combination with reciprocating flowing of damping fluid in the multiple cavities, and low-frequency swing and high-frequency harmonic waves of a main bearing are synchronously restrained. According to the design, the bearing capacity is guaranteed, vibration transmission is remarkably reduced, the service life of the main bearing is effectively prolonged, the operation reliability of a unit is improved, and the damping requirement of a core transmission system of a high-power wind turbine generator is met.

The present disclosure relates generally to flight control of electric aircraft and other powered aerial vehicles. In one embodiment, an electrical system for an aircraft is disclosed, comprising: at least one processor configured to: receive pilot input indicating a commanded aircraft state, determine an aircraft thrust for achieving the commanded aircraft state, retrieve at least one propeller parameter associated with propeller speeds, wherein the propeller parameter is determined to reduce a structural vibratory response in the aircraft. The at least one processor is further configured to determine a respective command for each propeller of the aircraft to achieve the determined aircraft thrust based on the at least one propeller parameter and control each propeller of the aircraft based on the corresponding respective command.

The invention relates to the technical field of engineering structure vibration reduction, in particular to a pressure-resistant and low-frequency vibration reduction light sandwich cylindrical shell structure which is obtained by a unit cell circumferential array and a linear array. Each unit cell comprises an inner panel, an outer panel and a grid interlayer, and the inner panel, the outer panel and the grid interlayer are made of the same material. The Archimedes spiral resonance groove is accurately engraved in the inner panel, so that the local resonance effect is excited, and effective vibration attenuation is achieved. The structure has the characteristics of integration of light weight, vibration reduction and noise reduction functions, wide vibration reduction frequency range, good hydrostatic pressure resistance, easiness in manufacturing and the like. And meanwhile, certain sound absorption performance can be realized without changing external geometric characteristics of the structure and adding extra materials.

The invention relates to a multi-layer sound absorption and insulation material and a preparation method thereof.The multi-layer sound absorption and insulation material comprises an inner micropore sound absorption layer, a vibration attenuation damping layer, a sound insulation plate layer, a main frame layer, a sound absorption material layer and an outer steel plate layer which are sequentially arranged from inside to outside, a plurality of hollow glass balls are evenly arranged in the main frame layer, and the sound absorption material layer is obtained by pressing multiple layers of composite sound materials; the composite acoustic material comprises the following raw materials in parts by weight: 10-15 parts of fibers, 4-8 parts of an adhesive, 3-8 parts of a foaming agent, 1-3 parts of a flame retardant, 10-20 parts of a plasticizer, 10-20 parts of resin, 1-3 parts of a lubricant, 5-10 parts of an organic sound absorber and 1-5 parts of an antioxidant. According to the sound absorption and insulation material, the inner micropore sound absorption layer, the vibration reduction damping layer, the sound insulation plate layer and other multi-layer structures are arranged from inside to outside, all the layers have a synergistic effect, sound wave propagation can be dealt with from multiple aspects, and the sound absorption and insulation material is suitable for various places with requirements for the acoustic environment, such as the fields of building sound insulation, industrial equipment noise reduction and the like.

The invention relates to a site micro-vibration attenuation test measuring point determination method and system, belongs to the technical field of vibration test, and solves the problem that vibration test measuring point arrangement depends on vibration source load accuracy or artificial experience in the prior art. The method comprises the following steps: determining a basic measuring point based on a target site parameter, obtaining an actual measurement vibration response, and calculating an actual measurement response transfer ratio; establishing an initial finite element model of the target site, and applying a preset load to the initial finite element model to obtain an initial finite element calculation result; according to the basic measuring points, corresponding model calculation points and predicted vibration responses are extracted, and predicted response transfer ratios are calculated; and performing model parameter updating by using the actually measured response transfer ratio and the predicted response transfer ratio, obtaining a basic finite element model, generating a vibration transfer form curve, obtaining vibration transfer characteristics, and determining the number and the positions of the measuring points. The micro-vibration transmission characteristics are accurately determined without depending on the vibration source load, and the number and the positions of the vibration attenuation test points are reasonably formulated.

The present invention relates to an active damper (1) for vibration attenuation in a boring bar (100) comprising an actuator (101) with electromagnets (4) attached to a body (2) thereof, and an inertial mass (3) in a cavity (12) of the actuator (101) movable in directions perpendicular to the longitudinal direction of the actuator (101); comprising an acceleration sensor (5) in the actuator (101) and control means (9) of currents of the electromagnets (4) depending on the measurements of the acceleration sensor (5).

The present invention discloses a novel combined vibration damping device with adjustable stiffness and damping, which relates to the technical field of vibration damping; it includes a magneto-resistive stress negative stiffness spring located inside the housing and a piezoelectric friction assembly located inside the bearing seat; a central shaft is connected between the two, and a metal helical spring is sleeved outside the central shaft. The bottom of the metal helical spring is connected to a spring base located at the top of the housing, and the top of the metal helical spring is connected to the bottom of the bearing seat; the central shaft is fixedly connected to the top inside the housing through a metal cross leaf spring. The magneto-resistive stress negative stiffness spring and the metal cross leaf spring can be connected in parallel to achieve the adjustment of quasi-zero stiffness, and the piezoelectric friction assembly can achieve the adjustment of damping; a load platform is fixedly arranged at the top of the bearing seat. The present invention has non-linear frequency-varying characteristics of high static stiffness - low dynamic stiffness, large low-frequency damping - small high-frequency damping, and can well solve the contradiction between the bearing capacity and the vibration damping frequency band, as well as the contradiction between high-frequency and low-frequency vibration attenuation, and achieve high-performance vibration damping.

The invention discloses an epoxy resin-based composite material with vibration damping performance and a preparation method and application thereof, and belongs to the technical field of carbon fiber reinforced composite materials. The carbon fiber reinforced epoxy resin matrix composite material is prepared from the following raw materials in parts by weight: 80-120 parts of epoxy resin, 10-50 parts of a curing agent and 5-10 parts of carbon nanotube / molybdenum disulfide and micron rubber co-embedded damping particles. The epoxy resin-based composite material disclosed by the invention is simple in raw materials, can be commercialized, and meets the low-altitude economic development requirements and the application requirements of aviation aircrafts; and the composite material has high specific strength, high damping vibration attenuation performance, electrical insulation performance and the like, and has a good application prospect in preparation of aircraft skin parts.

The invention discloses a water-turbine generator set damping device which comprises a main structure module comprising a damping vibration attenuation unit composed of a first linear spring, a first linear damper and a first mass block; the NES module comprises a second mass block, a first cavity coaxial with the second mass block is arranged in the second mass block, and an eddy current damping unit is arranged in the first cavity; the U-shaped flexible hinge comprises a U-shaped damping cylinder and a U-shaped flexible hinge unit arranged in the damping cylinder, the flexible hinge unit comprises a plurality of unit double-shaft flexible hinges which are sequentially connected in series through a connecting base body, the damping cylinder is filled with magnetorheological fluid, and the two ends of the flexible hinge unit are connected with the damping cylinder respectively. By adopting the combination mode of the main structure module, the U-shaped flexible hinge and the NES module, the vibration frequency band of 10-200 Hz can be covered, broadband vibration reduction is achieved, the vibration amplitudes in different directions such as the axial direction and the radial direction can be absorbed, and the vibration reduction requirement of a water turbine generator set in the complex hydraulic environment can be met.

An inerter-based metamaterial for low-frequency vibration attenuation includes a structural matrix material and an inerter array. The inerter array can be embedded within the structural matrix material. The inerter array can include a first inerter cell oriented along a first attenuation axis and a second inerter cell oriented along a second attenuation axis different from the first attenuation axis. The first inerter cell can include a first inerter. The second inerter cell can include a second inerter. The first inerter and the second inerter can be microinerters. The first inerter cell and the second inerter cell can be separated from each other by at least a portion of the matrix material. The first inerter cell and the second inerter cell can each include a first end and a second end and can each be connected to the matrix material at both the first end and the second end.

The invention discloses an active and passive composite vibration reduction system, and particularly relates to the technical field of vibration reduction equipment, the active and passive composite vibration reduction system comprises a bottom shell, a load platform, a passive vibration reduction device and an active vibration reduction device, and the passive vibration reduction device and the active vibration reduction device are both arranged between the bottom shell and the load platform; the passive damping device comprises a positive stiffness mechanism and a negative stiffness mechanism which are arranged in parallel; the active damping device comprises a controller, a sensor, a piezoelectric actuator and a flat plate type voice coil motor, the sensor is fixed on the load platform, the sensor, the piezoelectric actuator and the flat plate type voice coil motor are all in signal connection with the controller, and the controller processes signals transmitted by the sensor and transmits commands to the piezoelectric actuator and the flat plate type voice coil motor. The method has higher control precision, stronger anti-interference capability and more excellent adaptability and flexibility, the inherent frequency and the formant peak value of the damping device are effectively reduced, the high attenuation of high-frequency vibration is ensured, and broadband vibration attenuation is realized.

The invention discloses an anti-vibration stabilizing device for an air outlet pipeline of an electrolytic cell, a ring-shaped pipe frame is arranged on the periphery of a material pipeline in a full-surrounding or partial-surrounding manner, and a multi-layer composite vibration isolation part is filled between the inner side of the ring-shaped pipe frame and the contact side of the material pipeline; a self-adaptive damping adjusting piece is arranged between the ring-shaped pipe frame and the fixed frame body; the device further comprises a vibration data acquisition mechanism arranged on the material pipeline. And the multi-layer composite vibration isolation part has the wear-resisting and broadband damping capabilities through the wear-resisting layer and the damping layer, and the high-frequency vibration attenuation rate is larger than or equal to 90%. A honeycomb air cavity and a closed cavity are filled with media or open cavity micropores are designed, the rigidity and damping can be adjusted in a self-adaptive mode, and low-frequency buffering or specific-frequency resonance suppression is achieved. The regular hexagonal honeycomb structure is high in geometric stability and uniform in stress dispersion, the material consumption is reduced by 30-40%, the weight is reduced, and the anti-fatigue life is prolonged. The air cavity is axially and flexibly arranged, vibration in different directions is absorbed in a targeted mode, and the multi-dimensional damping effect is improved.

The utility model belongs to the technical field of damping vibration attenuation, and particularly relates to a viscous damper structure which comprises a damping cylinder body, a viscoelastic damping body is arranged at the top of the damping cylinder body in a sealing mode, a viscous damping body is filled in the damping cylinder body, and a movable shaft body penetrates through the middle of the viscoelastic damping body. One end of the movable shaft body extends into the viscous damping body and is provided with a movable terminal; the movable shaft body is of a hollow structure and is internally provided with an adjusting shaft, one end of the adjusting shaft is provided with an adjusting disc abutting against the movable terminal, and the movable terminal and the adjusting disc are provided with damping adjusting holes which are aligned in a one-to-one mode. The viscoelastic damping body is made of a pouring type high-damping material, has excellent vibration reduction characteristic, waterproof performance and sealing characteristic and basically has no additional rigidity, and the viscous damping body is made of a liquid type high-damping material, and is excellent in damping function and simple in structure; and meanwhile, the size of the damping adjusting hole in the movable terminal can be adjusted by rotating the adjusting disc, so that the purpose of adjusting the damping is achieved.

The invention belongs to the technical field of damping vibration attenuation materials, and particularly relates to a polyurethane damping vibration attenuation material and a preparation method and application thereof. According to the polyurethane damping vibration attenuation material provided by the invention, vegetable oil polyols such as poly (castor oil adipate) polyols, small molecular alcohols such as dipropylene glycol DPG and isophorone diisocyanate are introduced into the raw materials, the loss factor of the polyurethane material is increased to 0.42-0.57, and the polyurethane material also has the hardness of 50-70A, so that the performance of the polyurethane material is improved, and the service life of the polyurethane material is prolonged. The technical problems that in the prior art, polyurethane elastomers are low in performance and difficult to serve as damping vibration attenuation materials for cable trench / cable well cover plates are solved.

The invention discloses an aerodynamic damping rapid estimation method for a rotating blade, and the method comprises the steps: selecting a test impeller, obtaining an attenuation signal of a blade of the test impeller based on an impact test, and obtaining a structural damping ratio of the blade according to the attenuation signal through a free attenuation method and a nonlinear least square method; a BTT test technology is introduced, and the total damping ratio of the blade is obtained based on the BTT test technology and a nonlinear least square method; based on the structural damping ratio and the total damping ratio of the blade, an aerodynamic damping estimated value of the blade is obtained, and estimation of aerodynamic damping is achieved; according to the method, the BTT data analysis technology and the free vibration attenuation theory are combined, quantitative estimation of the aerodynamic damping ratio of the rotating blade is achieved, and the aerodynamic damping ratios of all the blades under different vibration pitch diameters can be determined; the pneumatic damping contribution of the rotating blade is quantitatively expressed, the vibration response mechanism of the blade in the service state can be deeply understood, and long-acting safe operation of a unit is guaranteed.

The invention discloses a directional traffic vibration attenuation method for a periodic pile-in-row composite foundation, and relates to the technical field of traffic vibration control and foundation treatment.The method comprises the specific steps that firstly, prefabricated modular pile bodies integrating various sensors and hydraulic adjusting assemblies are arranged at preset pile positions; continuously collecting various types of traffic vibration data; transmitting to a terminal for processing, and extracting a waveform category and a load dominant frequency parameter; according to the driving assembly, wave division type regulation and control are carried out, and pile row period parameters are dynamically optimized to form double matching; and finally finishing site construction deployment. According to the invention, traffic vibration data are comprehensively and accurately captured, and the problems of incomplete data acquisition, inaccurate waveform identification and the like in the prior art are solved; a double-matching mechanism is constructed, directional regulation and dynamic adjustment of piling parameters are performed according to different wave modes, the matching degree is made to reach 90% or above, automatic optimization and targeted attenuation of different types of traffic vibration can be achieved, the vibration attenuation effect is ensured to be stable and directional, and the limitation of the prior art is broken through.

The invention relates to the technical field of functional materials, in particular to a supramolecular aggregate modified vinyl resin material and a preparation method thereof. The supramolecular aggregate modified vinyl resin material is prepared from the following raw materials in parts by weight: 1.3 to 4.6 parts of aliphatic isocyanate monomer, 5 to 15 parts of micromolecular polyol, 0.8 to 2.9 parts of ureido pyrimidone monomer, 1 to 3 parts of curing agent, 50 to 100 parts of vinyl resin and 0.5 to 2.3 parts of accelerant, so that the modified vinyl resin material has reversible dynamic mechanical property; good damping vibration attenuation performance can be provided; and the material has good mechanical properties and excellent impact toughness, and can be widely applied to various fields as a high-performance functional material.

The embodiment of the present application provides a floor vibration monitoring method and device, electronic device, system and storage medium, the method comprising: obtaining sensing data of a vibration sensor, the vibration sensor is set on a target device, and multiple target devices are placed in a target area; obtaining floor vibration data of the target device based on the sensing data of the vibration sensor; adding the boundary conditions and vibration attenuation function of the target area and the floor vibration data of the target device to the two-dimensional dot matrix of the target area to form a parameter matrix; generating single-source vibration distribution data of multiple target devices based on the parameter matrix; synthesizing the single-source vibration distribution data of multiple target devices into multi-source vibration distribution data of the target area. The vibration data of multiple equipment points can be obtained at the same time, improving the detection efficiency and data accuracy, and the vibration conditions of the monitoring area are reflected by combining the vibration source distribution data of multiple equipment points in the parameter matrix.

The invention discloses a prefabricated concrete local resonance periodic vibration reduction road plate which comprises a base layer, a panel layer and a local resonance unit array layer, the local resonance unit array layer is arranged between the base layer and the panel layer, and the local resonance unit array layer, the base layer and the panel layer are integrally poured to form the prefabricated road plate. According to the prefabricated road plate formed in the scheme, through the stacked design of the rubber concrete base layer, the local resonance unit array layer and the rubber concrete face plate layer, the engineering vibration attenuation effect can be achieved on the basis that the strength requirement of the road plate is met. And secondly, through the synergistic effect of local resonance elastic wave band gap filtering and rubber concrete damping vibration attenuation, the vibration attenuation performance of the road plate is further enhanced, and the negative effects of vibration on human health and the working environment can be reduced.

The invention discloses a low-frequency vibration attenuation and noise reduction structure system for a subway tunnel and a design method, macromolecule geopolymer concrete adopted by the low-frequency vibration attenuation and noise reduction structure system for the subway tunnel is a simulated phonon crystal concrete ternary structure body, and the structure system comprises a vibration attenuation and isolation foundation ballast bed composite structure and a sound insulation and vibration attenuation composite structure; the vibration reduction and isolation foundation and ballast bed composite structure comprises a vibration isolation wall, a modified soil layer, vibration reduction piles, a foundation and a ballast bed. The vibration isolation wall is inserted into the foundation to form two side boundaries, the modified soil layer is arranged at the top of a groove formed by the vibration isolation wall and the foundation, the vibration reduction pile sequentially penetrates through the modified soil layer and the foundation from top to bottom, the bottom of the vibration reduction pile is flush with the bottom of the vibration isolation wall, and the track bed is arranged at the top of the modified soil layer. The sound insulation and vibration reduction composite structure comprises a sound insulation barrier layer and a vibration reduction wall. According to the low-frequency vibration and noise reduction structural system for the subway tunnel, high-molecular geopolymer concrete which is excellent in physical and chemical performance, stable in long-acting performance, low in carbon and environmentally friendly is adopted as a vibration reduction structural material, optimized low-frequency vibration and noise reduction and long-acting operation and maintenance of subway engineering can be achieved, and the low-frequency vibration and noise reduction structural system has the advantages of being simple in process, low in later-period maintenance cost, ecological, environmentally friendly and the like.

The invention relates to a suspension system and a vehicle, the suspension system comprises a power assembly and a semi-active damping pull rod, the semi-active damping pull rod is arranged at at least one end of the power assembly in the Y direction of the whole vehicle, one end of the semi-active damping pull rod is connected with the power assembly, and the other end of the semi-active damping pull rod is connected with an auxiliary frame; the semi-active damping pull rod is arranged at at least one end of the power assembly in the Y direction, so that the dynamic stiffness of the suspension system is lower and the vibration isolation performance is better under the idling and acceleration working conditions, the damping is larger under the low-frequency starting working condition, and the vibration attenuation of the power assembly is faster.

The invention relates to a multi-mode cooperative damping vibration attenuation method for a large-span bridge girder. The multi-mode cooperative damping vibration attenuation method comprises the following steps that the type and corresponding structural characteristics of the large-span bridge girder are determined; determining a target vibration reduction design requirement according to the girder type, wherein the target vibration reduction design requirement comprises a frequency range of vortex-induced vibration under different wind attack angles, a damping ratio minimum value corresponding to each order of frequency under a vertical modal shape, and a damping ratio minimum value corresponding to each order of frequency under a torsional modal shape; and determining a cooperative control scheme of the tower beam damper and the tuned mass damper mounted on the large-span bridge on the multi-modal vibration of the main beam according to the target vibration reduction design requirement. According to the multi-mode cooperative damping vibration attenuation method for the large-span bridge main beam, the tower beam damper and the tuned mass damper are installed on the large-span bridge main beam at the same time to be used in a combined mode so as to complete cooperative vibration attenuation design, and the purposes of improving the vibration attenuation effect and achieving full coverage of multi-mode vibration frequency are achieved. The problem of vortex-induced vibration reduction of the large-span bridge girder is solved.

The invention discloses a shock absorber and a subway vibration isolation trench applying the shock absorber. The shock absorber comprises an extension spring, a mass block, a supporting frame and a damper, and the extension spring is connected to the bottom of a passing plate; the mass block is connected with the extension spring; one end of the actuator is connected with the passing plate, and the other end is connected with the mass block; the support frame is mounted in the vibration isolation trench; one end of the damper is hinged with the support frame, and the other end is hinged with the mass block. The actuator applies real-time controllable braking force, vibration can be dynamically and reversely counteracted, the effective frequency band can be expanded, vibration under non-design working conditions can be restrained, the extension spring provides passive elastic restoring force, the system inherent frequency is adjusted, the main structure vibration frequency is matched, the damper dissipates kinetic energy, transient response is restrained, and therefore the resonance peak value is reduced, and vibration attenuation is accelerated. Through cooperation of the actuator, the extension spring and the damper, deep fusion of passive frequency tuning and active dynamic compensation is realized, and a broad-spectrum self-adaptive vibration control system is formed.