197 results about "Bridge vibration" patented technology

A method for bridge vibration testing and dynamic property recognition based on video monitoring comprises a step A of performing system construction, initial configuration and displacement obtaining; a step B of performing multipoint structure dynamic displacement obtaining, continuous collection and storage; a step C of preprocessing displacement time-history data; and a step D of processing free vibration response signals to obtain a modal parameter.

The invention discloses a dynamic simulation test system for ensuring running safety of a train on a railway bridge under an earthquake. The dynamic simulation test system comprises a bridge model and a train model, wherein a supporting frame component for supporting the bridge model and adjusting an inclination angle and a horizontal position of the bridge model is arranged at the bottom of the bridge model; track boards are paved on the bridge surface of the bridge model; train tracks for guiding a running route of the train model and central tracks for preventing the train model from falling off are paved on the track boards; the train tracks are parallel to the central tracks; the bridge model comprises a first supporting section for adjusting a preset speed of the train model through the inclination angle, a test section for performing a train-bridge coupling vibration test and a second supporting section for stopping the running of the train model according to the inclination angle; the first supporting section and the second supporting section are respectively connected to two ends of the test section. The weak action of the bridge, which is caused by the upper train, and strong action of bridge vibration, which is caused by a vibration table, are mutually coupled to realize a train and earthquake mixing simulation system.

Marching band string instruments and wearable string instruments are described that include a stiff waist band to prevent excessive side to side movement during use, while providing easy doff and don of the string instrument. String instruments also are provided with adjustable chest braces to allow accommodation for different player sizes and for minimization of back strain when playing the electric string instrument for extended time periods. Electric string instruments optionally have soft material interposed between bridge feet and a string instrument body, to allow a more resonant sound detection from a pickup located between the bridge feet and the body. Other advances include generation of a stereo signal from bridge vibrations, and electronic processing of sound that enhances the electric string instrument playing and learning experience.

The invention discloses an axle safety health assessment system and method based on axle coupling analysis, and relates to the field of bridge health monitoring. The axle safety health assessment system comprises an axle coupling analysis subsystem, a bridge health situation assessment system and a traffic safety assessment system, wherein the axle coupling analysis subsystem utilizes actual measurement data of a bridge health monitoring system to correct a bridge finite element model to obtain a bridge benchmark finite element model, and the bridge benchmark finite element model is used for carrying out axle coupling vibration analysis calculation to obtain a theoretical calculating value under an equal condition of the actual measurement data of the bridge health monitoring system; the bridge health situation assessment system compares the actual measurement data with the theoretical calculating value to assess the bridge health situation; the traffic safety assessment system utilizes the theoretical calculating value obtained through the axle coupling vibration analysis calculation and actual measurement bridge vibration data to assess a situation of the traffic safety. The theoretical data and the actual measurement data are combined to realize a purpose that the bridge health and the traffic safety are quantitatively analyzed and assessed, and the reliability of an assessment result is improved.

The invention discloses a device and a method for measuring the dynamic displacement of a bridge based on a mobile terminal. The mobile terminal is integrated with an acceleration sensor. The device comprises a parameter setting module, an acceleration measuring module, a vibration data processing module and a display module. The invention further discloses the measuring method comprising the following steps: the sampling length and the direction of measured acceleration are set; the mobile terminal is fixed to a bridge dynamic displacement monitoring point; an API provided by a mobile terminal operating system is called to access underlying hardware and read a bridge vibration signal acquired by the acceleration sensor; an acceleration time-history signal is obtained according to the bridge vibration signal, FFT transform is performed on the acceleration time-history signal, quadratic integral is carried out in a frequency domain to obtain a frequency domain signal of displacement, low-frequency noise is filtered by use of a low-frequency cutoff algorithm, and IFFT transform is performed on the processed frequency domain signal of displacement to obtain a time-history signal of displacement. The device and the method of the invention have the advantages of simple detection process, low cost, small size, convenient carrying, and no need for adding any hardware.

The invention relates to a vehicle-rail-bridge shaking table test device with a circular rail. The vehicle-rail-bridge shaking table test device comprises a vehicle model (3) used for simulating a high-speed rail train, a circulatory rail used for providing a circulatory running track for the vehicle model (3), a shaking table (4) used for simulating bridge earthquake states from the bottom of a bridge model (4), a guide section rail support (6) used for supporting the end of the circulatory rail from the bottom, and a test data acquiring device (12). An anti-loosening mechanism used for preventing the vehicle model (3) from falling off the circulatory rail is arranged between the vehicle model (3) and the circulatory rail.

The invention discloses a bridge vibration modal visual damage identification method based on machine learning, and the method comprises the following steps: S1, collecting the digital video information of bridge vibration, and carrying out the amplification processing of the digital video information; S2, acquiring parameters of the digital video image information, wherein the parameters comprisefrequency, phase and amplitude of the video image information; S3, constructing a visual modal image of the bridge vibration according to the phase and amplitude of the video image information; and S4, extracting multi-level feature information in the bridge visual modal image by using the convolutional neural network CNN, inputting the extracted feature information into a generalized regressionneural network GRNN, and carrying out identification estimation on the damage property of the bridge structure. According to the bridge vibration mode visual damage identification method based on machine learning, the structure of the bridge is detected through a small number of simple devices, the structural damage of the bridge can be accurately and comprehensively identified, and the method isscientific and efficient.

The invention relates to the field of bridge vibration, in particular to a hydraulic speed locking device for bridges. The hydraulic speed locking device for the bridges comprises a cylinder block, and a left cylinder cover and a right cylinder cover are arranged on the left and on the right of the cylinder block. The hydraulic speed locking device for the bridges is characterized in that two pistons are arranged in the cylinder block, a piston rod is penetratingly mounted in the cylinder block, the left end and the right end of the piston rod penetrate out of the left cylinder cover and the right cylinder cover respectively, each of the two pistons is provided with at least one mounting groove, the opening directions of the mounting grooves are opposite in direction, a through hole communicated with an inner chamber of the cylinder block is arranged at the bottom of each mounting groove, a gland is arranged at an opening of each mounting groove, each gland is provided with a through hole communicated with the inner chamber of the cylinder block, and a locking valve is inserted into each mounting groove from the opening thereof. The hydraulic speed locking device for the bridges is simple in structure, locking speed and locking force are unrelated to temperature, and influences on operating characteristics of the device caused by liquid temperature change during operation of the device are shielded fundamentally. A novel throttling mode and a novel configuration mode are adopted to enable operating performances of the device to be more stable.

The invention discloses a whole-space radiation noise prediction method of a rail transit bridge and a steel rail. The method comprises the following concrete steps: firstly, respectively establishing three-dimensional fine finite element models of a vehicle, a steel rail and a bridge, and acquiring the dynamic response of the bridge and the steel rail by means of time domain vehicle-rail-bridge coupling vibration analysis; secondly, obtaining modal acoustic vectors of the bridge and the steel rail by means of acoustic space Fourier transform, and calculating the radiation noise of the bridge and the steel rail at a near field point near a track center line by combining the dynamic response of the bridge and the steel rail; after that, respectively establishing a two-dimensional steel rail vibration acoustic coupling propagation model and a two-dimensional bridge vibration acoustic coupling propagation model, and solving the attenuation distribution laws of noise of the steel rail and the bridge at a far field point under the action of a steady-state excitation load by using an acoustic infinite element method; finally, selecting a certain near field point as a strong source point, and predicting the whole-space noise level of the bridge and the steel rail according to near field calculation results of the three-dimensional models and far field attenuation rates of the two-dimensional models.

The invention belongs to a method for reinforcing a bridge by external transverse prestressing tendons. The method is characterized in that finish-rolled deformed steel bars are used as the transverse prestressing tendons, the tensioning ends and the fixing ends of the transverse prestressing tendons are cone anchors. The finish-rolled deformed steel bars are used as the transverse prestressing tendons, so that influences of vehicle load and bridge vibration on anchoring effect are reduced; the tensioning ends and the fixing ends are the cone anchors, so that loss of prestress is reduced effectively; loss of prestress of the finish-rolled deformed steel bars in an operation period is low; and meanwhile, the finish-rolled deformed steel bars can be tensioned quite conveniently, are simple in structure and high in practicality, and has high popularization and application value.

The invention relates to a bridge vibration acceleration and inherent frequency on-line and real-time monitoring device, terminal and method. An acceleration vibration pickup device is used for sending a signal to a server by a dynamic data acquisition device, the server is used for performing Fourier transform on the signal to obtain a time travel curve of a real-time spectrum signal of vibration acceleration of a bridge structure and an inherent frequency of the bridge structure, performing counting analysis on a dynamic parameter of the bridge structure and calculating an average value and standard difference of the signal so as to determine a safety range of the dynamic parameter of a monitoring system, and warning information is sent to a network terminal when the bridge inherent frequency and acceleration signal value exceeds the safety range of the dynamic parameter. By the bridge vibration acceleration and inherent frequency on-line and real-time monitoring device, on-line and real-time monitoring and early warning can be performed on vibration acceleration and the inherent frequency of a bridge, the damage to the bridge structure can be accurately identified, the measurement requirement of the complicated bridge structure can be met, traffic on the bridge is not needed to be enclosed during measurement, and a measurement result is accurate.

The embodiment of the application discloses a bridge vibration detection method and related devices, which are applied to vibration detection equipment and include a camera device. The bridge vibration detection method comprises the following steps: collecting an original video of a bridge to be detected through the camera device, processing the original video according to a preset video processing strategy to obtain a target video with a motion amplification effect, and determining reference vibration data of the bridge to be detected according to the target video, wherein the motion magnification effect refers to that the area where the bridge to be detected moves is magnified in the target video; determining an operating mode of the bridge to be detected according to the reference vibration data; obtaining a pre-stored mode of the bridge to be detected; comparing the pre-stored mode and the operating mode to determine if the vibration state of the bridge to be detected is abnormal,wherein the pre-stored mode is the mode corresponding to a designed characteristic frequency of the bridge to be detected; and if so, outputting preset information. The bridge vibration detection method and related devices are beneficial to non-contact detection of a bridge vibration state, and improve the effectiveness, convenience, and versatility of vibration detection.

The invention discloses a bridge-vibration intelligent power supply system, which comprises an energy conversion device, an electric energy accumulation device and a power source management device, wherein the energy conversion device comprises a vibration transmission mechanism, a connecting rod, a crank and an engine; the vibration transmission mechanism transmits the vibration pressure of a bridge to a connecting rod firstly and then to the crank through the connecting rod; the crank is connected with an input shaft of the engine and used for driving the input shaft of the engine to rotateand generate electricity; the electric energy accumulation device comprises a rectification circuit, a conversion/process circuit I, a conversion/process circuit II, a super capacitor and a storage battery; the power source management device comprises an electric energy management controller and power source channels, a power source input terminal of the electric energy management controller is connected with a power source output terminal of an energy management device, and is connected with monitoring devices of bridges through a plurality of power source channels. The bridge-vibration intelligent power supply system has a compact structure, fully utilizes vibration pressure of the bridge when vehicles move on the bridge, and achieves the purposes of saving energy and electricity and ensuring the uninterrupted operation of the monitoring parts.

The invention provides a remote bridge vibration monitoring system, and the system comprises a laser emitter, an optical fiber coupler, optical fibers, a stepping motor, a plane mirror, an optical fiber collimating mirror, photoelectric detectors, and a signal transmitting module. The laser emitted by the laser emitter is divided into a plurality of laser beams through the optical fiber coupler, wherein the first laser beam irradiates on the rotatable plane mirror and is reflected by the plane mirror, and the reflected mirror irradiates the bottom surface of a bridge to form a line. The second laser beam is transmitted to a plurality of photoelectric detectors through optical fibers. The photoelectric detectors also receive scattered laser signals from the bottom surface of the bridge, and enable the signals received from the optical fibers to be transmitted to the signal transmitting module. The invention also provides a remote bridge vibration monitoring method. The system and method can achieve no contact with the bridge, can employ a solar cell to supply power, and can achieve the self-sufficiency of electric energy. Moreover, the system is simple in structure, and is easy to install.

The invention provides a quick vibration detection method for a bridge structure without traffic interruption and can realize vibration test on the bridge structure without traffic interruption. Multiple wireless acceleration sensors, multiple sensor wireless acquisition nodes and a vehicle-mounted mobile wireless base station are adopted, wherein the multiple wireless acceleration sensors are fixed and mounted on a bridge, each sensor wireless acquisition node is in radio signal connection with the multiple wireless acceleration sensors, vehicles pass the bridge surface quickly, and the vehicle-mounted mobile wireless base station receives data, acquired by the sensor wireless acquisition nodes, of the wireless acceleration sensors in the quick movement state. After the bridge vibration data are acquired, modal parameters of the bridge structure can be recognized with a modal parameter recognition method. The method can solve the problem of quick detection of urban area bridges and provides technical support for the safety of the bridge structure.

The invention belongs to the field of bridge vibration control in civil engineering, and particularly relates to a laminated magneto-rheological high damping elastomer single core support. The supportcomprises an upper steel disc, a lower steel disc, a laminated supporting mechanism and a lead core arranged at the upper steel plate, and an excitation mechanism arranged at the lower steel disc. The laminated supporting mechanism is cylindrical, and a round hole used for the lead core to penetrate is formed in the center of the laminated supporting mechanism. The laminated supporting mechanismis formed alternate vulcanization of the magneto-rheological elastomer and a steel plate. The excitation mechanism comprises an excitation coil, a reeling bracket and an iron core. The excitation coilis wound to the iron core by the reeling bracket. A round hole is formed in the middle of the iron core, and is used for positioning the lead core. The the lead core is fixed to the middle of the laminated supporting mechanism and the iron core, and therefore the positioning accuracy of the whole structure is guaranteed, and firmness of connection is improved. When shearing deformation of the support occurs, shearing deformation of the whole lead core occurs forced by the laminated supporting mechanism and the iron core, and therefore energy dissipation is achieved, and damping and rigidity of the support is improved overall.

The invention discloses an operation bridge vibration and health state abnormity early warning method based on a three-dimensional diagram. The method comprises the steps of testing and collecting an operation bridge acceleration response signal; carrying out pre-processing such as drift removal on the acceleration response signal; performing windowing function on acceleration response signals within a preset time length, calculating a power spectrum, and removing interference of excitation frequency; collecting the acceleration response signal power spectrums of a plurality of time periods into a three-dimensional diagram, and converting the three-dimensional diagram into a color plane graph or a gray plane graph; and judging bridge vibration abnormity and health state abnormityaccording to the change trend of each order of frequency and color or gray level change in the three-dimensional diagramso as to realize bridge early warning. According to the method, the vibration abnormity and the health state abnormity of the bridge can be effectively judged, so that early warning is given out, a structural analysis model is not needed, calculation is simple and convenient, environmental factor robustness is good, and good engineering applicability is achieved.

The invention discloses a bridge vibration deformation monitoring device and a real-time detection method. The bridge vibration deformation monitoring device includes a total station, a remote computer and a monitoring point. The 3D coordinates of the monitoring point are measured, and a 3D graph is plotted according to the 3D coordinates, so that the monitoring staff can acquire the vibration deformation of a bridge more visually. There is need to manually control a measurement part only once in the using process, and the subsequent work is automatically completed by control components. Thus,measurement error brought about by artificial control is reduced, and the accuracy of monitoring data is improved.

The invention discloses a high speed railway bridge vehicle-bridge vibration performance safety early warning method. The method includes acquiring the maximum value of the acceleration response amplitude for each passing train and the corresponding vehicle speed data, pairing the corresponding elements of two sets of sequences, and making an arrangement according to the vehicle sped; decomposing the acceleration response amplitude sequences of a main beam by means of wavelet packet decomposition, extracting the acceleration-vehicle speed median line, and determining the optimal wavelet packet decomposition parameters according to the matching degree of the acceleration amplitude mean of the acceleration sequence within the fixed sequence length; acquiring the fluctuation interval, surrounding the acceleration-vehicle speed median line, of the acceleration amplitude in each subsequence based on an interval estimation theory; and superimposing the acceleration fluctuation interval and the acceleration-vehicle speed median line to obtain the safety early warning interval of the high speed railway bridge vehicle-bridge vibration performance. Compared with the prior art, the method provided has the advantages of comprehensive consideration of factors, accurate and reasonable way, clear physical meaning, easy understanding and implementation, and wide application.

The application discloses a bridge vibration testing method. The method comprises the following steps: receiving a bridge vibration time sequence image collected by an unmanned aerial vehicle, and performing image correction processing on the bridge vibration time sequence image; performing relevancy analysis on the bridge vibration time sequence image after image correction processing by utilizing the digital image technology so as to obtain a vibration displacement travel curve; performing Fourier transform on the vibration displacement time travel curve and a force time travel curve acquired by testing excitation points so as to obtain a displacement frequency response function; performing modal analysis on the displacement frequency response function to obtain a modal parameter. The bridge vibration testing method disclosed by the invention can effectively guarantee the completeness of the testing data, and the applicability and convenience of the bridge vibration testing are improved. The application further discloses a bridge vibration testing device, equipment and system, and a computer readable storage medium with above technical effects.

The invention relates to the field of bridge construction, and discloses a bridge construction safety detection and alarm system which is used for detecting the potential safety hazards existing in the bridge construction in real time and warning and reminding the generated potential safety hazards to prevent the constructors from being injured. The system comprises a monitoring server, a mobile terminal, a communication module, a single-chip microcomputer, a data collector, a vibration sensor, an inclination angle sensor, an infrared detector, a current sensor, an infrared camera, an inclination angle comparison module and an image analysis module. The inclination angle sensor can detect the displacement of a bridge in real time under the condition of not referring to an external environment, and the infrared camera, the vibration sensor, the infrared detector and the current sensor are used for detecting and alarming the construction specifications of constructors, the bridge vibration, the approaching of the constructors to dangerous areas and the electrification of the metal parts, so that the potential safety hazards are eliminated in time, and the constructors are prevented from being injured. The bridge construction safety detection and alarm system is suitable for the bridge construction.

The invention relates to a rubber bearing structure based on the piezoelectric effect and a power generating system thereof; the rubber bearing structure comprises a bottom rubber layer; a reinforcing plate is arranged on the bottom rubber layer, and provided with a plurality of piezoelectric plates connected in parallel; a top rubber layer is arranged on the piezoelectric plates; the rubber bearing structure is arranged between a box girder and a pier of a bridge, and connected with a storage battery, thus powering up power devices on the bridge through a bridge power supply circuit. The rubber bearing structure can obtain large amplitudes along with bridge vibrations, thus giving large stress change amplitudes on the inner piezoelectric plates, ensuring piezoelectric plate deformation frequency level, improving power generating capacity and efficiency, and improving energy conversion efficiency; the power generating system is combined with the rubber bearing structure, so the installation and maintenance are easy; compared with large area installation and paving in the prior art, the rubber bearing structure and the power generating system are easy to construct, low in cost, and high in practical value.