CN114577897A - Nonlinear ultrasonic detection device and test method for pipeline grouting quality - Google Patents
Nonlinear ultrasonic detection device and test method for pipeline grouting quality Download PDFInfo
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- CN114577897A CN114577897A CN202210384111.1A CN202210384111A CN114577897A CN 114577897 A CN114577897 A CN 114577897A CN 202210384111 A CN202210384111 A CN 202210384111A CN 114577897 A CN114577897 A CN 114577897A
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Abstract
The invention relates to the technical field of ultrasonic detection, in particular to a nonlinear ultrasonic detection device and a test method for tunnel grouting quality, wherein the nonlinear ultrasonic detection device for tunnel grouting quality comprises a signal generator, an amplifier, an oscilloscope, a transmitting transducer and a receiving transducer, wherein the signal amplifier amplifies an ultrasonic signal of the signal generator to form an ultrasonic digital signal, the transmitting transducer converts the ultrasonic digital signal into an ultrasonic vibration signal and transmits the ultrasonic vibration signal to a test piece, and the receiving transducer converts the ultrasonic vibration signal passing through the test piece into a digital signal and transmits the digital signal to the oscilloscope; by designing a test piece and simulating the grouting damage condition of the pore channel, the nonlinear ultrasonic method is used for detecting the grouting damage condition of the pore channel, the high-precision detection effect can be achieved, and compared with other grouting detection methods, the method is more sensitive to damage and has less influence on a detected object.
Description
Technical Field
The invention relates to the technical field of ultrasonic detection, in particular to a nonlinear ultrasonic detection device and a test method for the grouting quality of a pore passage.
Background
The prestressed concrete structure is widely applied to civil engineering and water conservancy engineering, wherein prestressed tension control and sealing grouting are key steps of a prestressed post-tensioning method. The parameter used in the sealing grouting process is compactness, and the compactness is one of key parameters for evaluating the grouting quality of the prestressed concrete structure. When grouting in the pore channel is not compact enough, pores exist after grouting is finished in the pore channel, water molecules, carbon dioxide and the like in the air penetrate into the pores to react with the loaded steel strand mutually to generate corrosion and the like, so that the prestress of the whole structure is reduced, the steel strand is more easy to crack and break, and the service life and the normal use limit of the structure are greatly reduced.
The grouting detection of the pore canal belongs to damage detection according to the traditional method, and the damage of the pore canal during grouting or in the detection process can cause damage to the pore canal, thereby causing great inconvenience in practical engineering application
Disclosure of Invention
The invention aims to provide a nonlinear ultrasonic detection device and a test method for the grouting quality of a pore passage, and aims to solve the technical problems that the grouting detection of the pore passage in the prior art belongs to damage detection according to the traditional method, the damage is caused in the grouting of the pore passage or the detection process, and the great inconvenience is caused in the practical application of engineering.
In order to achieve the purpose, the invention provides a nonlinear ultrasonic detection device for the grouting quality of a pore passage, which comprises a signal generator, an amplifier, an oscilloscope, a transmitting transducer and a receiving transducer, wherein the signal generator is connected with the amplifier; the signal amplifier amplifies the ultrasonic signals of the signal generator to form ultrasonic digital signals, the transmitting transducer converts the ultrasonic digital signals into ultrasonic vibration signals and transmits the ultrasonic vibration signals to the test piece, and the receiving transducer converts the ultrasonic vibration signals penetrating through the test piece into digital signals and transmits the digital signals to the oscilloscope.
The invention also provides a nonlinear test method for the grouting quality of the duct, which adopts the nonlinear ultrasonic detection device for the grouting quality of the duct and comprises the following steps:
preparing a test piece, cleaning the surface to be tested of the test piece, determining the central axis of a pore passage, and arranging a test line and a test point;
a nonlinear ultrasonic testing system is set up, instrument parameters are set, a direct measurement method is carried out on a test piece, measurement is repeatedly carried out on a measuring point for many times until the waveform is stable, and then the next measuring point test is carried out after data are recorded and stored;
storing the test data in the USB flash disk, and storing after the test is finished;
and (3) sorting and analyzing the acquired data results, performing time-frequency conversion by using mathematical analysis software, drawing a frequency domain graph, reading corresponding frequency values from the graph, and substituting the frequency values into a nonlinear coefficient expression of a higher harmonic method to obtain a detection result.
The method comprises the following steps of preparing a test piece, cleaning the surface to be tested of the test piece, determining the central axis of a pore passage, and arranging a measuring line and a measuring point:
the plastic corrugated pipe is embedded in the preparation process of the test piece, another conventional PVC pipe with a smooth inner wall is taken as a grouting pipe of the grout, the grouting pipe is immediately sealed after the grouting is finished, the test piece is horizontally placed, and 5g of grout needs to be added when being weighed so as to prevent the actual grouting quality from being influenced.
The method comprises the following steps of constructing a nonlinear ultrasonic testing system, setting instrument parameters, carrying out direct butt-test on a test piece, repeatedly measuring at a measuring point for many times until a waveform is stable, recording and storing data, and then carrying out next measuring point test:
and coating coupling agent vaseline on two surfaces of a measuring point of the measured section, and respectively fixing the transmitting transducer and the receiving transducer to ensure that no hole is left between the two transducers and the surface to be measured of the test piece as much as possible.
The method comprises the following steps of constructing a nonlinear ultrasonic testing system, setting instrument parameters, carrying out direct butt-test on a test piece, repeatedly measuring at a measuring point for many times until a waveform is stable, recording and storing data, and then carrying out next measuring point test:
when some local measuring points have abnormal data, the encryption points are retested to determine the range, and the test is carried out in the surrounding area of the range to obtain more sufficient and effective data for later analysis.
According to the nonlinear ultrasonic detection device and the test method for the grouting quality of the pore channel, disclosed by the invention, the damage condition of the grouting of the pore channel can be effectively detected by designing a test piece and simulating the grouting damage working condition of the pore channel and detecting by using a nonlinear ultrasonic method, the high-precision detection effect can be achieved, and compared with other methods for detecting the grouting of the pore channel, the nonlinear ultrasonic detection device and the test method are more sensitive to damage and have less influence on a detected object.
Drawings
In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings used in the embodiments or the prior art descriptions will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative efforts.
Fig. 1 is a schematic block diagram of a nonlinear ultrasonic detection device for the grouting quality of a duct provided by the invention.
Fig. 2 is an installation schematic diagram of the non-linear ultrasonic testing device for tunnel grouting quality provided by the invention.
FIG. 3 is a graph of the amplitude of a second harmonic at an input frequency of 45kHz as provided by the present invention.
Fig. 4 is a perspective view of a concrete beam test piece provided by the present invention.
Fig. 5 is a front view of a concrete beam test piece provided by the present invention.
Fig. 6 is a plan view of a concrete beam test piece provided by the present invention.
FIG. 7 is a measuring point layout diagram of the non-linear testing method for grouting quality of a pore path provided by the invention.
FIG. 8 is a frequency domain plot for reading first order harmonic amplitudes, second order harmonic amplitudes, as provided by the present invention.
FIG. 9 is a flowchart illustrating the steps of a method for non-linear testing of grouting quality of a duct according to the present invention.
Detailed Description
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention. Further, in the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.
Referring to fig. 1 to 2, the present invention provides a nonlinear ultrasonic testing apparatus for pore grouting quality, including a signal generator, an amplifier, an oscilloscope, a transmitting transducer and a receiving transducer, wherein the signal generator is connected to the amplifier, the amplifier is electrically connected to the transmitting transducer, the receiving transducer is connected to the oscilloscope, and two ends of a test piece are respectively connected to the transmitting transducer and the receiving transducer.
In this embodiment, the signal amplifier amplifies the ultrasonic signal of the signal generator to form an ultrasonic digital signal, the transmitting transducer converts the ultrasonic digital signal into an ultrasonic vibration signal and transmits the ultrasonic vibration signal to the test piece, and the receiving transducer converts the ultrasonic vibration signal passing through the test piece into a digital signal and transmits the digital signal to the oscilloscope.
Referring to fig. 3 to 9, the present invention further provides a nonlinear testing method for grouting quality of a duct, which uses the nonlinear ultrasonic testing apparatus for grouting quality of a duct, and comprises the following steps:
s1: preparing a test piece, cleaning the surface to be tested of the test piece, determining the central axis of a pore passage, and arranging a test line and a test point;
s2: a nonlinear ultrasonic testing system is set up, instrument parameters are set, a direct measurement method is carried out on a test piece, measurement is repeatedly carried out on a measuring point for many times until the waveform is stable, and then the next measuring point test is carried out after data are recorded and stored;
s3: storing the test data in the USB flash disk, and storing after the test is finished;
s4: and (3) sorting and analyzing the acquired data results, performing time-frequency conversion by using mathematical analysis software, drawing a frequency domain graph, reading corresponding frequency values from the graph, and substituting the frequency values into a nonlinear coefficient expression of a higher harmonic method to obtain a detection result.
In step S1, a beam test piece is designed according to the design Specification for reinforced concrete and prestressed concrete bridges and culverts for highways (JTG3362-2018), wherein the length of the beam test piece is 300mm, the width of the beam test piece is 200mm, and the height of the beam test piece is 600 mm; the concrete compressive strength grade is designed to be C40; in the test beam test piece preparation process, a plastic corrugated pipe with the outer diameter of 85mm and the inner diameter of 80mm is adopted; in addition, the grouting pipe of the grout adopts a conventional PVC pipe with smooth inner wall, the inner diameter is 30mm, the outer diameter is 33mm, and the reference is made to FIG. 4; the working condition design is divided into setting PVC bellows and not setting PVC bellows in the grout pore, in addition, adopts classic grout mode gravity grouting, carries out defect control with the unsaturation index in the grout in-process, seals immediately after the grout is accomplished, and the level is placed. Specifically, the mode of taking the operating mode contrast prepares experimental roof beam test piece, has prepared 6 experimental roof beam test pieces under this type of operating mode that the thick liquid is not enough, and experimental roof beam test piece sets up the microdefect difference that the thick liquid is not enough in the pore except, and other conditions are all the same, and concrete operating mode design and implementation are as follows:
type N working conditions: the PVC corrugated pipe is not arranged in the hole channel of the type working condition, the gravity grouting is carried out in a classical grouting mode, the defect control is carried out according to the index of the degree of unsaturation in the grouting process, the sealing is immediately carried out after the grouting is finished, and the horizontal placement is carried out. This type of working condition sets up on three roof beam test pieces, numbers every corrugated pipe of every roof beam, is respectively: NZE0, NBZ1, NBZ2, NBZ 3; NBZ4, NBZ5, NBZ 6; NBZ7, NBZ8, see Table 1 for the degree of unsaturation associated with each channel. (in the table, the letters mean that the initial letter "N" represents the N-type working condition, "BZ" is the initial letter of the Chinese character phrase "deficiency," ZE "is the initial letter of" full amount, "wherein the working condition" NZE0 "has 0% unsaturation degree indicating that the grout is fully filled.)
TABLE 1 unsaturation degree corresponding to different channels under N-type working conditions
Y-type working condition: set up the PVC bellows under this type of condition, carry out the operating mode simulation on three roof beams, number every corrugated pipe of every roof beam, do respectively: YBZ1, YBZ2, YBZ3, YBZ4, YBZ5, YBZ 6; YBZ7, YBZ8, YZE 9. The defect type design was the same as the N-type case, and the unsaturation levels corresponding to each channel are shown in table 2 below. The first letter "Y" in the table represents Y-type working condition, other letters have the same meaning as above, and YBZ 1-YBZ 8 are pipelines containing different micro defects.
TABLE 2 unsaturation degree corresponding to different channels under Y-type working condition
In actual manufacturing, the initial mass of each beam is weighed, the corresponding pipeline is selected for full grouting with sufficient mass, weighing is carried out after the pipeline is completely filled, and the difference value of the two masses is the actual grouting mass. In consideration of possible residue of the grout after grouting, a plastic vessel with a smooth inner wall is adopted for grouting, and the residual mass is tested to be 5g, so that 5g is required to be added when the grout is weighed to prevent the actual grouting quality from being influenced.
In step S2, the incident frequency of the signal generator is selected to be 45kHz, fig. 3 is a graph of the amplitude of the second harmonic with an input frequency of 45kHz, and the gain voltages used during the test are 7V, 8V, 9V, 10V, and 11V, respectively. In the test process, the transmitting transducer and the receiving transducer are fixed on two corresponding sides of a concrete test piece after being knotted through the elastic bandage, preliminary polishing treatment is needed before the test, then after coupling agent vaseline is coated on the contact surfaces of the transmitting transducer and the receiving transducer, air between the two contact surfaces is removed, and the test can be carried out after the two contact surfaces are highly coupled.
In step S3, the test data are stored in the usb disk, and are stored after the test is completed, so as to facilitate the later analysis of the test data. The test data comprises the relation between the propagation time and the amplitude of the ultrasonic wave, and a time domain graph can be drawn at the later stage; after test data acquisition is completed, the coupling agent vaseline on the test block and the probe is cleaned up, so that the test block and the probe are convenient to use next time, and the surrounding environment is prevented from being polluted.
In step S4, the measured data is analyzed, time-frequency converted by mathematical analysis software, a frequency domain graph is drawn, the first order harmonic amplitude and the second order harmonic amplitude in the frequency domain graph are read, and as shown in fig. 8, the first order harmonic amplitude and the second order harmonic amplitude are substituted into a nonlinear coefficient expression:
in the formula, A0Is the first harmonic amplitude, A1Is the second order harmonic magnitude, k is the beam, and x is the distance. Since the beam k, the distance x is the same in the specific experiment, the formula is reduced as follows:
and substituting the data obtained by each measuring point into an expression to obtain a series of nonlinear coefficients, and researching the relation between the change of the grouting quality of the pore passage and the change of the nonlinear coefficients. Generally, the larger the nonlinear coefficient is, the more obvious the grouting quality contains defects. Through comparing with the nonlinear coefficient when concrete pore canal grouting is completely full, the numerical value of the pipeline with micro defects caused by insufficient grout can be obviously increased, and the characteristic can be used for identifying that micro defects exist in the grouting pipeline.
While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (5)
1. A nonlinear ultrasonic detection device for the grouting quality of a duct is characterized in that,
the device comprises a signal generator, an amplifier, an oscilloscope, a transmitting transducer and a receiving transducer, wherein the signal generator is connected with the amplifier, the amplifier is electrically connected with the transmitting transducer, the receiving transducer is connected with the oscilloscope, and two ends of a test piece are respectively connected with the transmitting transducer and the receiving transducer; the signal amplifier amplifies the ultrasonic signals of the signal generator to form ultrasonic digital signals, the transmitting transducer converts the ultrasonic digital signals into ultrasonic vibration signals and transmits the ultrasonic vibration signals to the test piece, and the receiving transducer converts the ultrasonic vibration signals penetrating through the test piece into digital signals and transmits the digital signals to the oscilloscope.
2. A nonlinear test method for the grouting quality of a duct, which adopts the nonlinear ultrasonic detection device for the grouting quality of the duct as claimed in claim 1, and is characterized by comprising the following steps:
preparing a test piece, cleaning the surface to be tested of the test piece, determining the central axis of a pore passage, and arranging a test line and a test point;
a nonlinear ultrasonic testing system is set up, instrument parameters are set, a direct measurement method is carried out on a test piece, measurement is repeatedly carried out on a measuring point for many times until the waveform is stable, and then the next measuring point test is carried out after data are recorded and stored;
storing the test data in the USB flash disk, and storing after the test is finished;
and (3) sorting and analyzing the acquired data results, performing time-frequency conversion by using mathematical analysis software, drawing a frequency domain graph, reading corresponding frequency values from the graph, and substituting the frequency values into a nonlinear coefficient expression of a higher harmonic method to obtain a detection result.
3. The method for the nonlinear test of the grouting quality of the pore canal as claimed in claim 2, wherein in the steps of preparing a test piece, cleaning the surface to be tested of the test piece, determining the central axis of the pore canal, arranging a measuring line and a measuring point:
the plastic corrugated pipe is embedded in the preparation process of the test piece, another conventional PVC pipe with a smooth inner wall is taken as a grouting pipe of the grout, the grouting pipe is immediately sealed after the grouting is finished, the test piece is horizontally placed, and 5g of grout needs to be added when being weighed so as to prevent the actual grouting quality from being influenced.
4. The method for the nonlinear test of the grouting quality of the pore passage as claimed in claim 3, wherein in the steps of building a nonlinear ultrasonic test system, setting instrument parameters, carrying out a direct measurement method on a test piece, repeatedly carrying out measurement on a measuring point for a plurality of times until the waveform is stable, recording and storing data, and then carrying out the next measuring point test:
and coating coupling agent vaseline on two surfaces of a measuring point of the measured section, and respectively fixing the transmitting transducer and the receiving transducer to ensure that no hole is left between the two transducers and the surface to be measured of the test piece as much as possible.
5. The method for the nonlinear test of the grouting quality of the pore passage as claimed in claim 4, wherein in the steps of building a nonlinear ultrasonic test system, setting instrument parameters, carrying out a direct measurement method on a test piece, repeatedly carrying out measurement on a measuring point for a plurality of times until the waveform is stable, recording and storing data, and then carrying out the next measuring point test:
when some local measuring points have abnormal data, the encryption points are retested to determine the range, and the test is carried out in the surrounding area of the range to obtain more sufficient and effective data for later analysis.
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| CN112666252A (en) * | 2020-12-03 | 2021-04-16 | 重庆交通大学 | Non-collinear mixing test system and method for nonlinear ultrasound |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN112666252A (en) * | 2020-12-03 | 2021-04-16 | 重庆交通大学 | Non-collinear mixing test system and method for nonlinear ultrasound |
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