CN113567559A - Ultrasonic detection device and method for corrosion of inhaul cable steel wire - Google Patents
Ultrasonic detection device and method for corrosion of inhaul cable steel wire Download PDFInfo
- Publication number
- CN113567559A CN113567559A CN202110849337.XA CN202110849337A CN113567559A CN 113567559 A CN113567559 A CN 113567559A CN 202110849337 A CN202110849337 A CN 202110849337A CN 113567559 A CN113567559 A CN 113567559A
- Authority
- CN
- China
- Prior art keywords
- steel wire
- ultrasonic
- probe
- signal
- corrosion
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
- G01N29/04—Analysing solids
- G01N29/07—Analysing solids by measuring propagation velocity or propagation time of acoustic waves
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
- G01N29/04—Analysing solids
- G01N29/06—Visualisation of the interior, e.g. acoustic microscopy
- G01N29/0654—Imaging
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
- G01N29/04—Analysing solids
- G01N29/11—Analysing solids by measuring attenuation of acoustic waves
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2291/00—Indexing codes associated with group G01N29/00
- G01N2291/01—Indexing codes associated with the measuring variable
- G01N2291/011—Velocity or travel time
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2291/00—Indexing codes associated with group G01N29/00
- G01N2291/01—Indexing codes associated with the measuring variable
- G01N2291/015—Attenuation, scattering
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2291/00—Indexing codes associated with group G01N29/00
- G01N2291/02—Indexing codes associated with the analysed material
- G01N2291/023—Solids
- G01N2291/0234—Metals, e.g. steel
Landscapes
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)
Abstract
The invention relates to an ultrasonic detection device and method for corrosion of a steel wire of a guy cable, wherein the device comprises the following components: the upper computer is connected with the ultrasonic transceiver and used for transmitting control instructions and processing data information to obtain a corrosion detection result of the measured steel wire; the ultrasonic transceiver is connected with the dry coupling ultrasonic probe and used for outputting an excitation signal to the probe and acquiring data information returned by the probe; the dry coupling ultrasonic probe is assembled with the limiting packaging structure and used for selecting an excitation mode and fixedly connecting with a measured steel wire. Compared with the prior art, the invention has the advantages of low cost and convenient operation, can quickly detect the stay cable steel wire through single-point excitation, does not cause additional damage and pollution to the cable body, can detect the wire breakage condition, and can position and evaluate the corrosion condition.
Description
Technical Field
The invention relates to the technical field of nondestructive testing, in particular to an ultrasonic testing device and method for inhaul cable steel wire corrosion.
Background
The main cable system is used as an important component of the cable-stayed bridge, generally consists of parallel steel wire bundles made of high-strength galvanized steel wires, can transmit the load and dead load of a bridge span structure of the cable-stayed bridge to a main tower, and is a main bearing part of the cable-stayed bridge structure. However, during the service period of the bridge, under the influence of external environments (such as vehicle load, wind load, temperature change and the like), the main cable system bears alternating loads with constantly changing magnitude and acceleration for a long time, and fatigue effect is easily generated to cause the cable to fail. In addition, the main cable system is generally exposed to the natural environment, especially in the severe air pollution area, the severe water pollution area, the seashore and the marine environment, when the anti-corrosion system is damaged in the construction stage or the fatigue stage caused by alternating load, the steel wire in the cable is easy to be corroded by the environment, so that the main cable system is corroded and damaged, especially in the anchoring area, due to the fact that the cable is arranged vertically or obliquely, rainwater permeates into the anchoring area along the cable body to form long-term accumulated water, and the corrosion degree is more serious than that of the free cable part. Under the combined action of fatigue damage and corrosion damage, the stay cable forms fracture damage, and if the stay cable is not processed in time, the service life of the bridge is greatly reduced, so that great loss is caused to personal safety and social economy.
At present, the detection means of the cable-stayed bridge cable at home and abroad is less, particularly the nondestructive detection means is in an exploration stage, and how to quickly and effectively detect the corrosion damage of the cable-stayed bridge cable is a great hot spot of the domestic and foreign nondestructive detection research. The existing nondestructive detection method for the damage of the inhaul cable mainly comprises the following steps: visual inspection, magnetic flux leakage, acoustic emission, radiation inspection, and ultrasonic guided wave. The visual detection method can only judge the more obvious damage on the surface of the cable body, but cannot judge the fine damage on the surface layer and the damage inside the cable body, cannot meet the requirement of the overall safety evaluation of the inhaul cable, and is only suitable for being used as an auxiliary detection means for checking at any time; in the aspects of peripheral inhaul cable broken wire and defect detection, a certain result is obtained by a magnetic flux leakage detection technology, but the method is difficult to detect in an anchoring area; the acoustic emission technology is a passive monitoring means, is mainly used for monitoring cable force and broken wires, is difficult to monitor cable corrosion, and cannot carry out quantitative analysis on damage size; the ray detection technology is difficult to transmit into the anchoring area, and the equipment is expensive and heavy and is inconvenient to use.
For the ultrasonic guided wave technology, chinese patent CN101393173A proposes a nondestructive testing method based on magnetostriction, which applies an instantaneous excitation magnetic field to a magnetic material to excite guided waves in a component, and then obtains reflected wave signals through the inverse magnetostriction effect, and analyzes the damage condition of the component to be tested according to the reflected wave signals, but the excitation signal of the scheme is weak, and it is difficult to test the central steel wire of a cable body, and the ultrasonic guided wave technology based on piezoelectric excitation has certain advantages for testing the stress, corrosion, defects, and broken wires of a cable, especially in an anchoring area, however, due to the long-term influence of factors such as rain, the anchoring area of the cable is far more susceptible to corrosion damage than other parts, resulting in broken wires. The Chinese patent CN107843651A adopts a mode of transmitting and receiving ultrasonic signals to realize defect detection, and analyzes the damage position and the damage depth of the steel wire by processing the received ultrasonic guided wave signals, but the method needs two detection surfaces and has great application difficulty.
Disclosure of Invention
The invention aims to overcome the defects in the prior art, and provides an ultrasonic detection device and method for the corrosion of a steel wire of a guy cable, so as to realize a technical scheme that the corrosion of the steel wire of the guy cable can be quickly detected by single-point excitation, and the technical scheme has the advantages of low manufacturing cost and convenience in operation.
The purpose of the invention can be realized by the following technical scheme: an ultrasonic detection device for corrosion of a steel wire of a guy cable comprises an upper computer, an ultrasonic transceiver and a dry coupling ultrasonic probe which are sequentially connected with each other, wherein the dry coupling ultrasonic probe is assembled and installed in a limiting packaging structure, the limiting packaging structure is connected with a measured steel wire, the measured steel wire is abutted against the end part of the dry coupling ultrasonic probe, and the upper computer is connected with the ultrasonic transceiver and used for transmitting a control instruction and processing received data information to obtain a corrosion detection result of the measured steel wire;
the ultrasonic transceiver is connected with the dry coupling ultrasonic probe and used for outputting an excitation signal in the form of an instantaneous high-voltage pulse to the dry coupling ultrasonic probe and acquiring data information returned by the dry coupling ultrasonic probe;
the dry coupling ultrasonic probe is assembled with the limiting packaging structure and used for selecting an excitation mode and fixedly connecting with a measured steel wire.
Further, spacing packaging structure includes location buckle and direction shell, location buckle and dry coupling ultrasonic probe be assembled between/be connected between, the location buckle is installed in the direction shell, the direction shell is connected with the measured steel wire.
Further, the location buckle includes the tight rubber ring that detains, the tight rubber ring cover of detaining is located and is done the coupling ultrasonic probe outside, install four perpendicular reset buttons that are used for being connected with direction shell block on the tight rubber ring, be 90 circumference array around the centre of a circle of the tight rubber ring between four perpendicular reset buttons and arrange, be provided with one in four perpendicular reset buttons and be used for arousing 0 perpendicular reset button of mode selection operation.
Furthermore, the dry coupling ultrasonic probe is rotatably assembled in a fastening rubber ring, and a raised thread is arranged in the fastening rubber ring and used for increasing the friction damping coefficient of the metal outer wall of the dry coupling ultrasonic probe and the inner wall of the fastening rubber ring so as to prevent the probe from falling off.
Further, the direction shell includes the main casing body and external fixation frame, the main casing body includes probe guide way and steel wire spacing groove, the lock ring is installed in the probe guide way, the probe guide way outside is located to the external fixation frame cover, the external fixation frame outside is provided with the screw hole, the external fixation frame passes through the bolt assembly in order to realize the fastening of doing coupling ultrasonic probe and vertically spacing to doing coupling ultrasonic probe, the steel wire spacing inslot joint has the quilt to be surveyed the steel wire.
Furthermore, four rectangular through holes used for being connected with the vertical reset button in a clamping mode are formed in the probe guide groove, the width of each rectangular through hole is matched with that of the corresponding vertical reset button to achieve transverse limiting, and the length of each rectangular through hole is larger than that of the corresponding vertical reset button to adjust and guide the longitudinal position of the dry coupling ultrasonic probe.
An ultrasonic detection method for corrosion of a steel wire of a guy cable comprises the following steps:
s1, determining detection frequency: the diameter and material parameters of a tested inhaul cable steel wire are obtained, a group velocity dispersion curve is obtained by solving a dispersion equation, and then the center frequency f of the dry coupling ultrasonic probe is determined according to the group velocity dispersion curve;
s2, selecting an excitation mode: assembling a dry coupling ultrasonic probe with the center frequency f with a limiting packaging structure in a required excitation mode, and connecting the dry coupling ultrasonic probe with an ultrasonic transceiver, wherein the ultrasonic transceiver gives instantaneous high-voltage pulses to the dry coupling ultrasonic probe as an excitation signal;
s3, calibrating an attenuation coefficient and a mode propagation speed: selecting one steel wire with the known length and the same parameters as those of the steel wire of the stay cable to be tested, testing in a required excitation mode, acquiring a guided wave signal propagated in the steel wire by using an ultrasonic transceiver, and processing the guided wave signal by using an upper computer to obtain an ultrasonic attenuation coefficient and a mode propagation speed;
s4, signal post-processing: the method comprises the following steps that an ultrasonic transceiver acquires a no-load signal of a dry coupling ultrasonic probe and a guided wave signal propagated by the dry coupling ultrasonic probe in a tested stay cable steel wire, and an upper computer performs post-processing on the no-load signal and the guided wave signal by combining an ultrasonic attenuation coefficient and a mode propagation speed to obtain a detection result;
s5, imaging of detection results: and imaging the detection result, and judging the corrosion degree of the stay cable steel wire according to the imaging result.
Further, the specific process of step S3 is as follows:
selecting one steel wire with the known length and the same parameters as those of the steel wire of the tested stay cable, and testing in a required excitation mode;
the guided wave returns to an excitation point after 2 times of steel wire length calibration, the ultrasonic transceiver collects guided wave signals S0 propagated in the steel wire by the probe, and performs band-pass filtering and continuous wavelet transformation on the signals S0 on an upper computer, and selects signals S0' corresponding to the frequency f;
extracting the maximum value Mi and the corresponding propagation time Ti of each echo in the signal S0';
carrying out linear fitting on the propagation time Ti and the corresponding propagation distance Di in the upper computer to obtain the group velocity of the propagation of the used mode in the stay cable steel wire:
wherein, CgThe group velocity obtained for fitting;
and simultaneously performing exponential fitting on the arrays Mi and Ti to obtain an ultrasonic attenuation formula:
wherein, alpha is the attenuation coefficient obtained by fitting, M0To fit the resulting initial echo amplitude.
Further, the specific process of step S4 is as follows:
the method comprises the steps that an ultrasonic transceiver collects a signal S1 when a dry-coupled ultrasonic probe is idle, band-pass filtering and continuous wavelet transformation are carried out on the signal S1, a signal corresponding to the frequency f is selected, Hilbert transformation is carried out on the signal to obtain a signal S1', and the maximum value A1 of signal noise outside a dead zone of the probe is recorded;
fixing a limiting packaging structure on the side surface of a tested stay cable, collecting a guided wave signal S2 propagated in a steel wire of the stay cable by a probe through ultrasonic transceiving equipment, carrying out band-pass filtering and continuous wavelet transformation on the signal, selecting a signal S2' corresponding to the frequency f, recording a signal amplitude DAi of a signal outside a dead zone of the probe, which is greater than A1, and simultaneously recording time Dti corresponding to the DAi after carrying out Hilbert transformation on the signal;
depth compensation is performed by the following formula:
the DAi 'is a signal amplitude value after depth compensation, so that a matrix Tij after depth compensation can be obtained, one row of data in the matrix is DAi', the other row of data is Dti, and the two rows of data are in one-to-one correspondence;
obtaining the maximum value Max _ DA 'in the array DAi' and the corresponding time Ti 'in Tij, substituting Ti' into the ultrasonic attenuation formula to obtain the corresponding signal amplitude M when the wire is brokenBreak-offWhen Max _ DA' and M are usedBreak-offWhen the relative difference is less than or equal to a preset threshold value, judging that the steel wire of the inhaul cable is broken;
further, the specific process of step S5 is as follows:
determining the position of the corrosion damage according to the following distance calculation formula:
and l is a distance, t is data in the array Dti collected in the step S4, the matrix Tij is converted into a distance-amplitude diagram, DAi' is mapped into a color diagram for display, and the corrosion degree of the stay wire is judged according to the corresponding amplitude of the color icon.
Compared with the prior art, the invention has the following advantages:
the corrosion detection method comprises the steps that an upper computer, an ultrasonic transceiver and a dry coupling ultrasonic probe which are sequentially connected with one another are arranged, the dry coupling ultrasonic probe is assembled and installed in a limiting packaging structure, the limiting packaging structure is connected with a measured steel wire, the measured steel wire is abutted against the end part of the dry coupling ultrasonic probe, and the upper computer is used for transmitting a control instruction and processing received data information to obtain a corrosion detection result of the measured steel wire; outputting an excitation signal to the dry coupling ultrasonic probe by utilizing the ultrasonic transceiver, and acquiring data information returned by the dry coupling ultrasonic probe; based on the assembly of the dry coupling ultrasonic probe and the limiting packaging structure, the selection operation of an excitation mode is carried out, so that a nondestructive testing mode with low cost and convenient operation is realized, and meanwhile, the on-site rapid detection can be carried out on the stay wire by single-point excitation.
Secondly, the invention adopts a dry coupling ultrasonic probe to match with a limiting packaging structure, on one hand, compared with the traditional ultrasonic detection mode, the invention does not need to use a coupling agent, does not cause additional damage and pollution to the stay cable body, on the other hand, can carry out the selective assembly of an excitation mode according to the requirement, and can ensure the reliable connection and fixation with the steel wire of the tested stay cable, thereby improving the reliability of the detection result.
The upper computer is connected with the ultrasonic transceiver, the upper computer processes and calculates probe signals acquired by the ultrasonic transceiver, the mode propagation speed can be calculated through linear fitting, the ultrasonic attenuation coefficient can be calculated through exponential fitting, whether the stay cable steel wire is broken or not can be judged through depth compensation, and the corrosion damage position and the corrosion degree can be determined through distance calculation and imaging processing, so that the broken wire condition of the stay cable steel wire can be detected, and the corrosion condition of the steel wire can be positioned and evaluated.
Drawings
FIG. 1 is a schematic diagram of the apparatus of the present invention;
FIG. 2 is a schematic view of a positioning buckle structure according to the present invention;
FIG. 3 is a schematic view of the structure of the guide housing of the present invention;
FIG. 4 is a schematic flow chart of the method of the present invention;
FIG. 5 is a dispersion curve of the steel wire of the stay cable in the embodiment;
FIG. 6 is a graph of the fitting of the calibrated steel wire guided wave signal S0' and the attenuation coefficient in the embodiment
FIG. 7 is a schematic diagram of the probe no-load signal S1' collected in the embodiment
FIG. 8 is a schematic diagram of a corroded steel wire signal S2' received by the probe of the embodiment;
FIG. 9 is an imaging result of the corrosion wire signal after color mapping processing in the example;
the notation in the figure is: 1. host computer, 2, supersound transceiver, 3, dry coupling ultrasonic probe, 4, spacing packaging structure, 5, surveyed steel wire, 401, location buckle, 402, direction shell.
Detailed Description
The invention is described in detail below with reference to the figures and specific embodiments.
Examples
As shown in fig. 1 to 3, an ultrasonic detection device for detecting corrosion of a steel wire of a cable comprises an upper computer 1, an ultrasonic transceiver 2 and a dry coupling ultrasonic probe 3 which are sequentially connected with each other, wherein the dry coupling ultrasonic probe 3 is assembled in a limiting encapsulation structure 4, the limiting encapsulation structure 4 is connected with a measured steel wire 5, the measured steel wire 5 is abutted against the end part of the dry coupling ultrasonic probe 3, and the upper computer 1 is connected with the ultrasonic transceiver 2 and is used for transmitting a control instruction and processing received data information to obtain a corrosion detection result of the measured steel wire 5;
the ultrasonic transceiver 2 is connected with the dry coupling ultrasonic probe 3 and is used for outputting an excitation signal in the form of an instantaneous high-voltage pulse to the dry coupling ultrasonic probe 3 and acquiring data information returned by the dry coupling ultrasonic probe 3;
the dry coupling ultrasonic probe 3 is assembled with the limit packaging structure 4 and is used for selecting an excitation mode and fixedly connecting with the tested steel wire 5.
The limiting packaging structure comprises a positioning buckle 401 and a guide shell 402, the positioning buckle 401 is connected with the dry coupling ultrasonic probe 3 in an assembling mode, the positioning buckle 401 is installed in the guide shell 402, and the guide shell 402 is connected with a measured steel wire 5. Specifically, the positioning buckle 401 includes a fastening rubber ring, the fastening rubber ring is sleeved outside the dry coupling ultrasonic probe 3, four vertical reset buttons for being clamped and connected with the guide shell 402 are mounted on the fastening rubber ring, the four vertical reset buttons are arranged in a 90-degree circumferential array around the center of the fastening rubber ring, one of the four vertical reset buttons is provided with a 0-degree vertical reset button for performing excitation mode selection operation, the dry coupling ultrasonic probe 3 is rotatably assembled in the fastening rubber ring, and a raised thread is arranged in the fastening rubber ring and is used for increasing the friction damping coefficient between the metal outer wall of the dry coupling ultrasonic probe 3 and the inner wall of the fastening rubber ring to prevent the probe from falling off;
the direction shell 402 includes the main casing body and the external fixation frame, the main casing body includes probe guide way and steel wire spacing groove, the tight rubber ring of detaining is installed in the probe guide way, the probe guide way outside is located to the external fixation frame cover, the external fixation frame outside is provided with the screw hole, the external fixation frame passes through the bolt assembly in order to realize the fastening of doing coupling ultrasonic probe 3, and to doing coupling ultrasonic probe 3 vertically spacing, steel wire spacing inslot joint has surveyed steel wire 5, set up four rectangle through-holes that are used for the block to connect the vertical reset button on the probe guide way, the width of rectangle through-hole matches with the width of vertical reset button in order to realize horizontal spacing, the length of rectangle through-hole is greater than the length of vertical reset button, adjust the direction with the longitudinal position to doing coupling ultrasonic probe 3.
In this embodiment, the whole ultrasonic detection device includes an upper computer 1, an ultrasonic transceiver 2, a dry-coupled ultrasonic probe 3, and a limit packaging structure 4. The upper computer 1 is connected with the ultrasonic transceiver 2 and is used for transmitting instructions and post-processing waveform data; the ultrasonic transceiver 2 is connected with the dry coupling ultrasonic probe 3 and is used for exciting and receiving ultrasonic waves; the dry coupling ultrasonic probe 3 is assembled with the limit packaging structure 4, is used for selecting an excitation mode, and is fixedly connected with the measured steel wire 5.
Spacing packaging structure 4 comprises two parts of location buckle 401 and direction shell 402, and wherein location buckle 401 contains perpendicular reset button and the rubber ring of fastening, and direction shell 402 contains main casing body and external fixation frame:
the fastening rubber ring is in a hollow cylindrical shape, the inner diameter length of the fastening rubber ring is matched with the outer diameter of the dry coupling ultrasonic probe 3, and the probe can be ensured to be rotatably assembled into the rubber ring; the inner wall of the rubber ring is provided with a convex thread line for increasing the friction damping coefficient between the metal outer wall of the probe and the inner wall of the rubber ring and preventing the probe from falling off; the rubber ring is provided with 4 rectangular through holes in a 90-degree circumferential array around the column shaft and used for assembling a vertical reset button, the vertical reset button is rectangular, and the size of the rectangular through holes is matched with the external size of the reset button;
the main casing comprises probe guide way and steel wire spacing groove two parts: the probe guide groove is of a cylindrical thin-wall structure, 4 rectangular through holes are formed in the structure around a cylindrical shaft according to a 90-degree circumferential array, the width of each rectangular through hole is matched with the width of a reset button to realize transverse limiting, the positioning buckle 401 is ensured to be coaxial with the center of the main shell, the length of each rectangular through hole is greater than that of the reset button, and the probe guide groove can be used for adjusting the longitudinal position of a probe to realize guide; the steel wire limiting groove is in a circular truncated cone shape, a groove is formed inwards from the center of the end face of the circular truncated cone to the position near the guide groove, the groove is in a trapezoidal shape and is not communicated with the guide groove to form a limiting clamping groove, convex grains are arranged on the inner wall of the groove to enhance the friction coefficient between the limiting groove and the steel wire, the grooving width of the end face of the circular truncated cone is not larger than the diameter of the measured steel wire so as to ensure that the measured steel wire can be well clamped and fixed, in addition, the steel bar limiting groove part is made of a plastic material with higher stiffness coefficient, and the limiting effect on the steel bar can be further enhanced;
the external fixing frame is sleeved outside the probe guide groove in a columnar ring shape, and threaded holes are periodically arranged outside the frame and used for assembling bolts after the longitudinal position of the probe is adjusted, so that the fastening effect of the probe is realized, and the longitudinal limit is performed on the probe.
In practical application, the diameter of the dry coupling ultrasonic probe 3 is not more than 20mm, and the dominant frequency is not more than 200 kHz.
The ultrasonic detection device is applied to practice to realize nondestructive detection of the corrosion of the steel wire of the stay cable, and the process is shown in figure 4 and comprises the following steps:
1. determining the detection frequency: and (3) acquiring the diameter and material parameters (density, Young modulus and Poisson ratio) of the steel wire of the tested stay cable, and solving a frequency dispersion equation to obtain a group velocity frequency dispersion curve. And selecting a proper frequency f according to the frequency section with slow change rate and less modes on the group velocity frequency dispersion curve to determine the center frequency of the dry coupling ultrasonic probe.
2. Selecting an excitation mode: and assembling the dry coupling ultrasonic probe with the center frequency f with a limiting packaging structure in a required excitation mode, and connecting the dry coupling ultrasonic probe with ultrasonic transceiver equipment. The ultrasound transceiver gives a momentary high voltage pulse to the probe as an excitation signal.
3. Calibrating attenuation coefficient and mode propagation speed: and selecting one steel wire with the known length and the same parameters as those of the steel wire of the tested stay cable, and testing in a required excitation mode. The guided wave returns to an excitation point after 2 times of the length of the steel wire is calibrated, the ultrasonic transceiver acquires a guided wave signal S0 transmitted by the probe in the inhaul cable, and performs band-pass filtering and continuous wavelet transformation on the signal S0 on the upper computer to select a signal S0' corresponding to the frequency f. The maximum Mi of each echo in the signal S0' and the corresponding propagation time Ti are then extracted. And performing linear fitting on the propagation time Ti (unit ms) and the corresponding propagation distance Di (unit mm) in the upper computer to obtain a group velocity formula:
i.e. the group velocity at which the mode used propagates within the cable wire.
And simultaneously carrying out exponential fitting on the arrays Mi (unit V) and Ti (unit ms) to obtain an ultrasonic attenuation formula:
wherein alpha is an attenuation coefficient obtained by fitting and has a unit of db/mm; m0The initial echo amplitude obtained by fitting is in a unit of V; cgThe group velocity obtained for the fit is in m/s.
4. Signal processing: the ultrasonic transceiver collects signals S1 when the probe is idle, band-pass filtering and continuous wavelet transformation are carried out on the signals, signals corresponding to the frequency f are selected, Hilbert transformation is carried out on the signals to obtain signals S1', and the maximum value A1 of signal noise outside the dead zone of the probe is recorded. The detection device is fixed on the side surface of a tested inhaul cable, the ultrasonic transceiver acquires guided wave signals S2 transmitted by a probe in the inhaul cable, band-pass filtering and continuous wavelet transformation are carried out on the signals, a signal S2' corresponding to the frequency f is selected, after Hilbert transformation is carried out on the signals, the signal amplitude DAi of the signals outside a dead zone of the probe, which are greater than the value A1, is recorded, and meanwhile, the time Dti corresponding to the DAi is recorded. Depth compensation is performed by the following formula:
wherein alpha is the attenuation coefficient obtained by calibration in the step 3, CgAnd obtaining a matrix Tij after depth compensation for the mode corresponding group velocity, wherein one column of the matrix is the compensated signal amplitude DAi' and the other column is Dti, and the two columns are in one-to-one correspondence.
In step 4, the maximum value Max _ DA ' in the array DAi ' and its corresponding time Ti ' in Tij are obtained. Since the ultrasonic attenuation formula is already obtained in step 3
Substituting Ti' into the signal amplitude M of the corresponding broken wireBreak-off. When Max _ DA' and MBreak-offWhen the relative difference value of the two-dimensional tension is within 10% of the threshold value set in the embodiment, the steel wire of the inhaul cable is judged to be broken.
5. And (4) imaging: according to the distance calculation formula
Determining the position of the corrosion damage, wherein l is the distance, CgAnd (3) for the mode corresponding to the group velocity, t is data in the array Dti collected in the step (3), so that the matrix Tij is converted into a distance-amplitude diagram, DAi' is mapped into a color diagram for display, and the corrosion degree of the stay wire steel wire is judged according to the amplitude corresponding to the color icon.
In this embodiment, the above technical solution is applied, and the assembling process includes:
firstly, a dry coupling ultrasonic probe with the diameter of 14mm is assembled with a positioning buckle in a limiting packaging structure. During assembly, the 0-degree vertical reset button on the rubber ring and the piezoelectric piece of the probe are in the same direction of vibration. The probe assembled with the positioning buckle is connected with the guide shell, the vertical reset button is pressed during connection until the probe is assembled with the rectangular through hole, and an excitation mode is selected during the step, wherein the probe excites a longitudinal mode in the steel wire when the probe is in the same direction with the slotting direction of the end face of the circular truncated cone in the direction of 0 degree, and excites a torsional mode when the probe is vertical. And after the measured stay cable steel wire is deeply inserted into the groove from the groove until the measured stay cable steel wire is contacted with the end part of the probe, assembling bolts on an external fixing frame to realize the fastening effect of the probe and longitudinally limit the probe.
Finally, the upper computer is connected with the ultrasonic transceiver and used for transmitting instructions and post-processing waveform data; and connecting the ultrasonic transceiver with the dry coupling ultrasonic probe for exciting and receiving ultrasonic waves.
The detection process comprises the following steps:
1. using a dry coupling probe system to measure the diameter of 7mm and the density of 7850kg/mm3And the Young's modulus of 200GPa and the Poisson ratio of 0.29. Firstly, the dispersion curve of the guided waves in the steel wire is solved, as shown in figure 5, only three guided wave modes exist in the frequency band with the frequency of 0-100kHz, and the group velocity difference between the modes is obvious, so that the dry coupling ultrasonic probe with the center frequency of 50kHz is selected.
2. In this embodiment, the torsional mode is selected for detection. And assembling the probe and the limiting packaging structure, wherein a torsion mode is selected during assembly. And simultaneously connecting the probe with the ultrasonic transceiver. The ultrasound transceiver device gives it a momentary high voltage pulse of 40V as an excitation signal.
3. And selecting a steel wire with the same parameters as the steel wire of the tested inhaul cable and the length of 600mm to calibrate the attenuation coefficient, and testing in a torsional excitation mode. The guided wave returns to the excitation point after 2 times of the calibrated steel wire length, the ultrasonic transceiver acquires a guided wave signal S0 propagated by the probe in the inhaul cable, and performs band-pass filtering and continuous wavelet transformation on the signal S0 on the upper computer, and selects a signal S0' corresponding to the frequency f, as shown in FIG. 6. The maximum value Mi of each echo in the signal S0' and the corresponding propagation time Ti are extracted. Linearly fitting the propagation time Ti and the corresponding propagation distance Di in the upper computer to obtain a velocity formula
I.e. the group velocity at which the mode used propagates within the stay wire, this example wire is 3241 m/s. Meanwhile, carrying out exponential fitting on the arrays Mi and Ti to obtain an ultrasonic attenuation formula
Where α is the attenuation coefficient obtained by fitting, 2.03 × 10 in this example-4db/mm。
4. Collecting the idle time of the dry coupling ultrasonic probeThe dead zone of the probe is 0.26ms, signal S1. After the signal is subjected to band-pass filtering of 20-100kHz, continuous wavelet transform with Morlet wavelet as a basis function is performed, a signal corresponding to the frequency of 50kHz is selected, Hilbert transform is performed on the signal to obtain a signal S1', and as shown in FIG. 7, the maximum value A0 of signal noise outside the dead zone of the probe is recorded to be 0.0054. The steel wire to be tested is clamped into the fixing device until the head of the probe is contacted with the steel wire, a guided wave signal S2 transmitted by the probe in the inhaul cable is collected, band-pass filtering is carried out on the signal at 20-100kHz, continuous wavelet transformation with Morlet wavelet as a basis function is carried out, a signal corresponding to the frequency of 50kHz is selected, Hilbert transformation is carried out on the signal to obtain a signal S2', as shown in figure 8, the amplitude DAi of the signal outside the dead zone of the probe, which is greater than the value A1, is recorded, and the time Dti corresponding to the DAi is recorded. By the formula
Depth compensation is carried out, wherein alpha is the attenuation coefficient obtained by calibration in the step 3, CgAnd obtaining a matrix Tij after depth compensation for the mode corresponding group velocity, wherein one column of the matrix is DAi', one column is Dti, and the two columns are in one-to-one correspondence.
5. According to the distance calculation formula
And determining the corrosion damage position, converting the matrix Tij into a distance-amplitude map, and mapping the distance-amplitude map into a color map for display, as shown in FIG. 9. It can be seen from the figure that corrosion damage starts at 740mm and is most severe at about 1000 mm.
In conclusion, the invention has low realization cost and lower manufacturing cost compared with the detection equipment of other nondestructive detection methods; the invention has convenient operation, the device can be portable and fixed, and single-point excitation can quickly carry out on-site operation on a single stay cable steel wire; compared with the traditional ultrasonic detection method, the dry coupling ultrasonic probe is used, a coupling agent is not needed, no additional damage or pollution is caused to the cable body, the corrosion degree can be positioned and evaluated, and the broken wire condition can be detected.
Claims (10)
1. The ultrasonic detection device for the corrosion of the steel wire of the inhaul cable is characterized by comprising an upper computer (1), an ultrasonic transceiver (2) and a dry coupling ultrasonic probe (3), wherein the upper computer, the ultrasonic transceiver (2) and the dry coupling ultrasonic probe (3) are sequentially connected with one another, the dry coupling ultrasonic probe (3) is assembled and installed in a limiting packaging structure (4), the limiting packaging structure (4) is connected with a measured steel wire (5), the measured steel wire (5) is abutted to the end part of the dry coupling ultrasonic probe (3), and the upper computer (1) is connected with the ultrasonic transceiver (2) and used for transmitting a control instruction and processing received data information to obtain a corrosion detection result of the measured steel wire (5);
the ultrasonic transceiver (2) is connected with the dry coupling ultrasonic probe (3) and is used for outputting an excitation signal in the form of instantaneous high-voltage pulse to the dry coupling ultrasonic probe (3) and acquiring data information returned by the dry coupling ultrasonic probe (3);
the dry coupling ultrasonic probe (3) is assembled with the limiting packaging structure (4) and used for selecting an excitation mode and fixedly connecting with a measured steel wire (5).
2. The ultrasonic detection device for detecting the corrosion of the steel wire of the inhaul cable according to claim 1, wherein the limiting packaging structure (4) comprises a positioning buckle (401) and a guide outer shell (402), the positioning buckle (401) is assembled and connected with the dry coupling ultrasonic probe (3), the positioning buckle (401) is installed in the guide outer shell (402), and the guide outer shell (402) is connected with the steel wire (5) to be detected.
3. The ultrasonic detection device for detecting the corrosion of the steel wire of the inhaul cable according to claim 2, wherein the positioning buckle (401) comprises a fastening rubber ring, the fastening rubber ring is sleeved outside the dry coupling ultrasonic probe (3), four vertical reset buttons used for being connected with the guide shell (402) in a clamping mode are mounted on the fastening rubber ring, the four vertical reset buttons are arranged in a 90-degree circumferential array around the center of the fastening rubber ring, and one 0-degree vertical reset button used for carrying out excitation mode selection operation is arranged in each vertical reset button.
4. The ultrasonic detection device for detecting the corrosion of the steel wire of the inhaul cable according to claim 3, wherein the dry coupling ultrasonic probe (3) is rotatably assembled in a fastening rubber ring, and a raised thread is arranged in the fastening rubber ring and is used for increasing the friction damping coefficient of the metal outer wall of the dry coupling ultrasonic probe (3) and the inner wall of the fastening rubber ring so as to prevent the probe from falling off.
5. The ultrasonic detection device for detecting the corrosion of the steel wire of the inhaul cable according to claim 3, wherein the guide outer shell (402) comprises a main shell and an external fixing frame, the main shell comprises a probe guide groove and a steel wire limiting groove, the fastening rubber ring is installed in the probe guide groove, the external fixing frame is sleeved outside the probe guide groove, a threaded hole is formed in the external fixing frame, the external fixing frame is assembled through bolts to achieve the fastening of the dry coupling ultrasonic probe (3) and longitudinally limit the dry coupling ultrasonic probe (3), and the steel wire (5) to be detected is clamped in the steel wire limiting groove.
6. The ultrasonic detection device for detecting the corrosion of the steel wire of the inhaul cable according to claim 5, wherein four rectangular through holes for clamping and connecting the vertical reset button are formed in the probe guide groove, the width of each rectangular through hole is matched with that of the vertical reset button so as to realize transverse limiting, and the length of each rectangular through hole is greater than that of the vertical reset button so as to adjust and guide the longitudinal position of the dry coupling ultrasonic probe (3).
7. An ultrasonic testing method for the corrosion of a steel wire of a guy cable by using the ultrasonic testing device as claimed in claim 1, which is characterized by comprising the following steps:
s1, determining detection frequency: the diameter and material parameters of a tested inhaul cable steel wire are obtained, a group velocity dispersion curve is obtained by solving a dispersion equation, and then the center frequency f of the dry coupling ultrasonic probe is determined according to the group velocity dispersion curve;
s2, selecting an excitation mode: assembling a dry coupling ultrasonic probe with the center frequency f with a limiting packaging structure in a required excitation mode, and connecting the dry coupling ultrasonic probe with an ultrasonic transceiver, wherein the ultrasonic transceiver gives instantaneous high-voltage pulses to the dry coupling ultrasonic probe as an excitation signal;
s3, calibrating an attenuation coefficient and a mode propagation speed: selecting one steel wire with the known length and the same parameters as those of the steel wire of the stay cable to be tested, testing in a required excitation mode, acquiring a guided wave signal propagated in the steel wire by using an ultrasonic transceiver, and processing the guided wave signal by using an upper computer to obtain an ultrasonic attenuation coefficient and a mode propagation speed;
s4, signal post-processing: the method comprises the following steps that an ultrasonic transceiver acquires a no-load signal of a dry coupling ultrasonic probe and a guided wave signal propagated by the dry coupling ultrasonic probe in a tested stay cable steel wire, and an upper computer performs post-processing on the no-load signal and the guided wave signal by combining an ultrasonic attenuation coefficient and a mode propagation speed to obtain a detection result;
s5, imaging of detection results: and imaging the detection result, and judging the corrosion degree of the stay cable steel wire according to the imaging result.
8. The ultrasonic testing method for the corrosion of the steel wire of the inhaul cable according to claim 7, wherein the specific process of the step S3 is as follows:
selecting one steel wire with the known length and the same parameters as those of the steel wire of the tested stay cable, and testing in a required excitation mode;
the guided wave returns to an excitation point after 2 times of steel wire length calibration, the ultrasonic transceiver collects guided wave signals S0 propagated in the steel wire by the probe, and performs band-pass filtering and continuous wavelet transformation on the signals S0 on an upper computer, and selects signals S0' corresponding to the frequency f;
extracting the maximum value Mi and the corresponding propagation time Ti of each echo in the signal S0';
carrying out linear fitting on the propagation time Ti and the corresponding propagation distance Di in the upper computer to obtain the group velocity of the propagation of the used mode in the stay cable steel wire:
wherein, CgThe group velocity obtained for fitting;
and simultaneously performing exponential fitting on the arrays Mi and Ti to obtain an ultrasonic attenuation formula:
wherein, alpha is the attenuation coefficient obtained by fitting, M0To fit the resulting initial echo amplitude.
9. The ultrasonic testing method for the corrosion of the steel wire of the inhaul cable according to claim 8, wherein the specific process of the step S4 is as follows:
the method comprises the steps that an ultrasonic transceiver collects a signal S1 when a dry-coupled ultrasonic probe is idle, band-pass filtering and continuous wavelet transformation are carried out on the signal S1, a signal corresponding to the frequency f is selected, Hilbert transformation is carried out on the signal to obtain a signal S1', and the maximum value A1 of signal noise outside a dead zone of the probe is recorded;
fixing a limiting packaging structure on the side surface of a tested stay cable, collecting a guided wave signal S2 propagated in a steel wire of the stay cable by a probe through ultrasonic transceiving equipment, carrying out band-pass filtering and continuous wavelet transformation on the signal, selecting a signal S2' corresponding to the frequency f, recording a signal amplitude DAi of a signal outside a dead zone of the probe, which is greater than A1, and simultaneously recording time Dti corresponding to the DAi after carrying out Hilbert transformation on the signal;
depth compensation is performed by the following formula:
the DAi 'is a signal amplitude value after depth compensation, so that a matrix Tij after depth compensation can be obtained, one row of data in the matrix is DAi', the other row of data is Dti, and the two rows of data are in one-to-one correspondence;
number of acquisitionsThe maximum value Max _ DA ' in the group DAi ' and the corresponding time Ti ' in the group Tij are substituted into the ultrasonic attenuation formula, and the corresponding signal amplitude M in the case of wire breakage can be obtainedBreak-offWhen Max _ DA' and M are usedBreak-offWhen the relative difference is smaller than or equal to a preset threshold value, the steel wire of the inhaul cable is judged to be broken.
10. The ultrasonic testing method for the corrosion of the steel wire of the inhaul cable according to claim 9, wherein the specific process of the step S5 is as follows:
determining the position of the corrosion damage according to the following distance calculation formula:
and l is a distance, t is data in the array Dti collected in the step S4, the matrix Tij is converted into a distance-amplitude diagram, DAi' is mapped into a color diagram for display, and the corrosion degree of the stay wire is judged according to the corresponding amplitude of the color icon.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110849337.XA CN113567559B (en) | 2021-07-27 | 2021-07-27 | Ultrasonic detection device and method for corrosion of inhaul cable steel wire |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110849337.XA CN113567559B (en) | 2021-07-27 | 2021-07-27 | Ultrasonic detection device and method for corrosion of inhaul cable steel wire |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113567559A true CN113567559A (en) | 2021-10-29 |
| CN113567559B CN113567559B (en) | 2022-11-18 |
Family
ID=78167840
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110849337.XA Active CN113567559B (en) | 2021-07-27 | 2021-07-27 | Ultrasonic detection device and method for corrosion of inhaul cable steel wire |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113567559B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US11733090B1 (en) * | 2022-02-08 | 2023-08-22 | Halliburton Energy Services, Inc. | Marine animal monitoring during seismic surveying using distributed acoustic sensing |
Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2908516A1 (en) * | 2006-11-09 | 2008-05-16 | Commissariat Energie Atomique | Ultrasonic waves transmitting and/or receiving method for controlling e.g. preconstraint cable, involves using probe for reception of waves, where probe has characteristics permitting to create reproduced distribution for emission |
| CN101943681A (en) * | 2010-08-24 | 2011-01-12 | 浙江大学 | Method for judging and positioning bridge cable corrosion |
| CN102841143A (en) * | 2012-08-29 | 2012-12-26 | 广东电网公司电力科学研究院 | Method for detecting corrosion of grounded grid circular steel bar based on lateral loading of piezoelectric sensors |
| CN103940911A (en) * | 2014-04-30 | 2014-07-23 | 武汉理工大学 | Detection device and method for service bridge inhaul cable/suspension cable anchor system |
| CN104634873A (en) * | 2015-01-28 | 2015-05-20 | 同济大学 | Ultrasonic detection system and method for damage of steel wires in bridge-cable anchoring area |
| CN104865317A (en) * | 2015-04-23 | 2015-08-26 | 同济大学 | Transmission type air coupling ultrasonic scanning imaging method |
| CN105548360A (en) * | 2016-01-18 | 2016-05-04 | 北京科技大学 | Stress concentration and ultrasonic guided wave based composite stay cable rusting monitoring method |
| CN107843651A (en) * | 2017-11-28 | 2018-03-27 | 中铁大桥科学研究院有限公司 | A kind of ultrasonic guided wave detecting method and system of the damage of bridge cable steel wire |
| US20190086369A1 (en) * | 2016-04-22 | 2019-03-21 | Mitsubishi Electric Corporation | Rope damage diagnostic testing apparatus |
| CN110554088A (en) * | 2019-09-29 | 2019-12-10 | 中国科学院声学研究所 | Air coupling ultrasonic detection method for defects |
| CN112057105A (en) * | 2020-09-11 | 2020-12-11 | 中国科学院长春光学精密机械与物理研究所 | Ultrasonic probe pressure adjusting device |
-
2021
- 2021-07-27 CN CN202110849337.XA patent/CN113567559B/en active Active
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2908516A1 (en) * | 2006-11-09 | 2008-05-16 | Commissariat Energie Atomique | Ultrasonic waves transmitting and/or receiving method for controlling e.g. preconstraint cable, involves using probe for reception of waves, where probe has characteristics permitting to create reproduced distribution for emission |
| CN101943681A (en) * | 2010-08-24 | 2011-01-12 | 浙江大学 | Method for judging and positioning bridge cable corrosion |
| CN102841143A (en) * | 2012-08-29 | 2012-12-26 | 广东电网公司电力科学研究院 | Method for detecting corrosion of grounded grid circular steel bar based on lateral loading of piezoelectric sensors |
| CN103940911A (en) * | 2014-04-30 | 2014-07-23 | 武汉理工大学 | Detection device and method for service bridge inhaul cable/suspension cable anchor system |
| CN104634873A (en) * | 2015-01-28 | 2015-05-20 | 同济大学 | Ultrasonic detection system and method for damage of steel wires in bridge-cable anchoring area |
| CN104865317A (en) * | 2015-04-23 | 2015-08-26 | 同济大学 | Transmission type air coupling ultrasonic scanning imaging method |
| CN105548360A (en) * | 2016-01-18 | 2016-05-04 | 北京科技大学 | Stress concentration and ultrasonic guided wave based composite stay cable rusting monitoring method |
| US20190086369A1 (en) * | 2016-04-22 | 2019-03-21 | Mitsubishi Electric Corporation | Rope damage diagnostic testing apparatus |
| CN107843651A (en) * | 2017-11-28 | 2018-03-27 | 中铁大桥科学研究院有限公司 | A kind of ultrasonic guided wave detecting method and system of the damage of bridge cable steel wire |
| CN110554088A (en) * | 2019-09-29 | 2019-12-10 | 中国科学院声学研究所 | Air coupling ultrasonic detection method for defects |
| CN112057105A (en) * | 2020-09-11 | 2020-12-11 | 中国科学院长春光学精密机械与物理研究所 | Ultrasonic probe pressure adjusting device |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US11733090B1 (en) * | 2022-02-08 | 2023-08-22 | Halliburton Energy Services, Inc. | Marine animal monitoring during seismic surveying using distributed acoustic sensing |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113567559B (en) | 2022-11-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US9568452B2 (en) | Non-contact signal propagation property evaluation of synthetic fiber rope | |
| CN111678629B (en) | Ultrasonic monitoring probe for internal service stress of ocean structural member | |
| US9127998B1 (en) | Active ultrasonic method of quantifying bolt tightening and loosening | |
| CN101398409B (en) | Automatic detection method for oblique incidence wave technology steel plate and device thereof | |
| CN104807888A (en) | Non-collinear mixing ultrasonic testing method for microcrack length measurement | |
| CN108088913B (en) | Piezoelectric ultrasonic guided wave probe for flaw detection of steel rail bottom and flaw detection method thereof | |
| CN113567559B (en) | Ultrasonic detection device and method for corrosion of inhaul cable steel wire | |
| CN207689438U (en) | Supersonic guide-wave angle probe for rail examination | |
| CN106770683A (en) | Composite T-shaped bonding pad liquid self coupling ultrasound closes transducer and detection method | |
| Cawley | Guided waves in long range nondestructive testing and structural health monitoring: Principles, history of applications and prospects | |
| Rizzo et al. | Effect of frequency on the acoustoelastic response of steel bars | |
| JPH0511895B2 (en) | ||
| JP2005148064A (en) | Device and method for detecting change or damage to pressure vessel during or after pressure test | |
| EP1181545B1 (en) | Method and device for determining the condition of longitudinally stretched connecting elements and for testing the same using ultrasound | |
| CN207689437U (en) | Piezoelectric supersonic guided wave probe for the flaw detection of the rail flange of rail | |
| JP2001074706A (en) | Method for diagnosing ground anchor | |
| JP2006023215A (en) | Ultrasonic inspection method, ultrasonic inspection device and guide wave transducer for the ultrasonic inspection device | |
| Michaels et al. | Self‐Calibrating Ultrasonic Methods for In‐Situ Monitoring of Fatigue Crack Progression | |
| JP4646012B2 (en) | Nondestructive inspection equipment for concrete structures | |
| Xu et al. | Detection of impulsive signals on tendons for hybrid wind turbines using acoustic emission measurements | |
| CN114002331B (en) | Method for detecting damage degree of steel strand | |
| Tse et al. | Guided-waves technique for inspecting the health of wall-covered building risers | |
| JP2002071650A (en) | Method of ultrasonic flaw detection for hollow concrete column | |
| Li et al. | Frequency Shift-Based Debonding Localization of Steel Concrete Composite Structures | |
| CN117686590A (en) | Ultrasonic detection section imaging device and method for concrete quality |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |