CN101446572A - Device for detecting cavity beneath structure panel by instantaneous impulsion method and detection method thereof - Google Patents
Device for detecting cavity beneath structure panel by instantaneous impulsion method and detection method thereof Download PDFInfo
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- CN101446572A CN101446572A CNA2008102333916A CN200810233391A CN101446572A CN 101446572 A CN101446572 A CN 101446572A CN A2008102333916 A CNA2008102333916 A CN A2008102333916A CN 200810233391 A CN200810233391 A CN 200810233391A CN 101446572 A CN101446572 A CN 101446572A
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Abstract
The invention discloses a device for detecting cavity beneath a structure panel by the instantaneous impulsion method and a detection method thereof. The device comprises a vibration device, an acceleration sensor, a signal amplifier, a data acquisition instrument and a computer; the acceleration sensor is arranged on a structure panel to be detected; and when the structure panel to be detected is vibrated by the vibration device, the acceleration sensor and the structure panel to be detected vibrate synchronously; and the vibration response signal output terminal of the acceleration sensor is input to the computer after passing through the signal amplifier and the data acquisition instrument sequentially. By utilizing difference between a dense surface layer and a basal body cavity surface layer in the response frequency and the response frequency or amplitude under instantaneous impulsion, the detection device provided by the invention is able to quickly and accurately obtain the results of detection of whether cavity is formed beneath the structure panel, is capable of preventing the detection results from being disturbed by outside noise, is convenient and simple to be operated, provides a accurate reference for early discovery and treatment of cavity beneath the structure panel. The device has the advantages of simple structure and low manufacture cost.
Description
Technical field
The present invention relates to the pick-up unit and the detection method of coming to nothing under a kind of structural panel, the transient impact method pick-up unit and the detection method of coming to nothing under particularly a kind of structural panel.
Background technology
Come to nothing under the structural panel be owing to separate between inborn panel and basic unit or the day after tomorrow surface layer plasticity flexure recover that the back forms.After the appearance of coming to nothing under the concrete flag, because road maintenance and environment reason, the zone of coming to nothing can the development gradually along with the prolongation of life cycle.Because the existence of coming to nothing, variation has taken place in the load that causes carload to produce maximum flexural tensile stress in the plate body of road surface, produce maximum flexural tensile stress value and sharply increase, and along with the increase of the region area that comes to nothing, the load transfer ability drop of road is very fast with the expanded range in the district of coming to nothing, if not early detection and improvement, will make the road deck early fracture, reduce road deck serviceable life, simultaneously, also increase the danger of driving vehicle, reduced comfortableness.Other structure for another example, coming to nothing as body of wall also exists similar problem.
For solving the problem of the early detection of coming to nothing under the structural panel, application number is that 200710027724.5 patented claim discloses sound shake empty detection method of method cement pavement panel collet and detector, obtain to knock the voice signal of road deck by the direct sound sensor, through the conclusion of whether being come to nothing after the Computer Analysis; Though this method early detection road surface is to a certain extent gone to a grassroots level and come to nothing, it is apparent in view to be subjected to external interference, when ambient noise is big, and the accuracy that detects of influence then; Simultaneously, knock road surface itself and produce sound, also can make testing result produce error, in addition, utilize gravity owing to knock, therefore, the method can't detect the phenomenon of coming to nothing of vertical planes such as body of wall.
Therefore, the transient impact method pick-up unit that comes to nothing under a kind of structural panel of needs can be got rid of the interference of outside noise to testing result, and is simple to operation, can obtain testing result fast and accurately, provide accurate foundation for coming to nothing under early detection and the administration structure panel.
Summary of the invention
In view of this, the purpose of this invention is to provide the transient impact method pick-up unit and the detection method of coming to nothing under a kind of structural panel, can get rid of the interference of outside noise to testing result, simple to operation, can obtain testing result fast and accurately, provide accurate foundation for coming to nothing under early detection and the administration structure panel, apparatus structure is simple, and cost is low.
The transient impact method pick-up unit that comes to nothing under the structural panel of the present invention, comprise exciting device, acceleration transducer, signal amplifier, data collecting instrument and computing machine, described acceleration transducer is arranged on the structural panel to be detected, when structural panel to be detected is subjected to the exciting device exciting, guarantee acceleration transducer and structural panel synchronous vibration to be detected; The vibration response signal output terminal of acceleration transducer is successively by signal amplifier and data collecting instrument input computing machine.
Further, described exciting device is provided with force transducer, and the signal output part of described force transducer is successively by pressure signal amplifier and data collecting instrument input computing machine;
Further, described exciting device is the driver of exciting force quantification, comprise support, shell, pull bar, guide pole and tup, described shell is arranged on the support, shell is provided with upper end cover and bottom end cover, described guide pole is provided with in the enclosure in mode moving up and down, and pull bar passes upper end cover fixedlys connected with the guide pole upper end, and tup passes bottom end cover fixedlys connected with the guide pole lower end; Between guide pole upper end and the upper end cover force application spring is set, between guide pole lower end and the bottom end cover return spring is set; Described force transducer is arranged on the tup lower end;
Further, described acceleration transducer is close on the structural panel to be detected;
Further, described tup lower end is provided with the tup pad, and described force transducer is arranged between tup pad and the tup lower end.
The invention also discloses a kind of method of coming to nothing under the transient impact method pick-up unit detection architecture panel that comes to nothing under the structural panel of utilizing, may further comprise the steps:
A. degree of will speed up sensor is close on the structural panel to be detected, utilizes exciting device to knock structural panel to be detected, records compact structure panel natural frequency or/and amplitude, and with natural frequency or/and amplitude value is stored to computing machine;
B. select sensing range and at least one check point is set at structural panel to be detected, to acceleration transducer be set on the check point, utilize exciting device moment impact structural panel to be detected, record the check point vibration frequency or/and amplitude, and with natural frequency or/and amplitude ratio.
Further, among the step a, described exciting device is the driver of exciting force quantification, and the force application spring of the driver of adjustment exciting force quantification and the rigidity of return spring make the maximum elastic force situation of force application spring lower ram only impact once check point;
Further, among the step b, described check point evenly distributes on structural panel;
Further, exciting device is provided with force transducer, among step a and the step b, in moment impact structural panel to be detected, utilizes force transducer to record impulsive force numerical value, makes the impulsive force quantification;
Further, among step a and the step b, described acceleration transducer adopts the mode of being close to be arranged on the structural panel to be detected.
The invention has the beneficial effects as follows: the transient impact method pick-up unit and the detection method of coming to nothing under the structural panel of the present invention, utilize close-knit surface and matrix to come to nothing the response frequency of surface layer under transient impact or/and amplitude is different, can obtain the testing result of whether coming to nothing under the structural panel fast and accurately, can get rid of the interference of outside noise to testing result, simple to operation, provide accurate foundation for coming to nothing under early detection and the administration structure panel, apparatus structure is simple, low cost of manufacture; Exciting device is provided with force transducer, can with the big or small quantification of transient impact power or according to transient impact power and panel vibration frequency or/and the corresponding relation between the amplitude is analyzed testing result, make testing result more accurate; Adopt the driver of exciting force quantification, further guarantee the accuracy of testing result; Exciter structure is simple, utilizes the excitation spring to knock, and therefore can be used for the empty detection of body of wall holder; Acceleration transducer closely sticks on the structural panel to be detected, and assurance acceleration transducer and check point vibration are carried out synchronously, make testing result more accurate.
Description of drawings
Below in conjunction with drawings and Examples the present invention is further described.
Fig. 1 is a structural principle synoptic diagram of the present invention;
Fig. 2 is the exciter structure synoptic diagram.
Embodiment
Structural panel to be detected is a concrete road surface structure in the present embodiment.
The transient impact method pick-up unit that comes to nothing under the structural panel of present embodiment, comprise exciting device 2, acceleration transducer 1, signal amplifier 4, data collecting instrument 5 and computing machine 6, acceleration transducer 1 is arranged on the structural panel 7 to be detected, when structural panel 7 to be detected is subjected to exciting device 2 excitings, guarantee acceleration transducer 1 and structural panel 7 synchronous vibrations to be detected, in the present embodiment, acceleration transducer 1 is close on the structural panel 7 to be detected, and the vibration response signal output terminal of acceleration transducer 1 is successively by signal amplifier 4 and data collecting instrument 5 input computing machines 6;
Certainly, exciting device 2 is not limited to the structure of present embodiment, also can be other force application apparatus such as weight, can both reach goal of the invention; Acceleration transducer 1 is not limited to be close on the structural panel 7 to be detected, also can be arranged on the structural panel 7 to be detected by other rigid member, can realize goal of the invention equally.
The method of coming to nothing under the transient impact method pick-up unit detection architecture panel that comes to nothing under the structural panel of the present invention may further comprise the steps:
A. degree of will speed up sensor 1 is close on the structural panel 7 to be detected, with exciting device 2 moment impacts structural panel 7 to be detected, the force application spring of the driver of adjustment exciting force quantification and the rigidity of return spring make the maximum elastic force situation of force application spring lower ram only impact once check point; Record compact structure panel natural frequency and amplitude, and natural frequency and amplitude value are stored to computing machine 6; Exciting device 2 is the driver of aforementioned exciting force quantification; Simultaneously, utilize force transducer 8 to record impulsive force numerical value, make the impulsive force quantification.
B. select sensing ranges and be arranged on equally distributed a plurality of check points on the structural panel at structural panel 7 to be detected, acceleration transducer 1 will closely be pasted on each check point, utilize exciting device 2 moment impacts structural panel 7 to be detected, record check point vibration frequency and amplitude, and with natural frequency and amplitude ratio, simultaneously, utilize force transducer 8 to record impulsive force numerical value, make the impulsive force quantification, guarantee that the numerical value of each transient impact power of impacting is constant or keep within the specific limits;
Under the prerequisite of impulsive force quantification, if there is the check point vibration frequency to be significantly less than natural frequency, or the check point amplitude then has the phenomenon of coming to nothing obviously greater than intrinsic amplitude, detects otherwise reselect check point; This detection mode has been eliminated the influence of other disturbing factors such as noise, and testing result is objective, accurate.
Detect frequency and amplitude simultaneously, can obtain multinomial data, guarantee result's accuracy.
Certainly, in the testing process, also natural frequency or amplitude can be only detected, equally also goal of the invention can be reached.
Explanation is at last, above embodiment is only unrestricted in order to technical scheme of the present invention to be described, although the present invention is had been described in detail with reference to preferred embodiment, those of ordinary skill in the art is to be understood that, can make amendment or be equal to replacement technical scheme of the present invention, and not breaking away from the aim and the scope of technical solution of the present invention, it all should be encompassed in the middle of the claim scope of the present invention.
Claims (10)
1. the transient impact method pick-up unit that comes to nothing under the structural panel, it is characterized in that: comprise exciting device (2), acceleration transducer (1), signal amplifier (4), data collecting instrument (5) and computing machine (6), described acceleration transducer (1) is arranged on the structural panel to be detected (7), when structural panel to be detected (7) is subjected to exciting device (2) exciting, guarantee acceleration transducer (1) and structural panel to be detected (7) synchronous vibration; The vibration response signal output terminal of acceleration transducer (1) is successively by signal amplifier (4) and data collecting instrument (5) input computing machine (6).
2. the transient impact method pick-up unit that comes to nothing under the structural panel according to claim 1, it is characterized in that: described exciting device (2) is provided with force transducer (8), and the signal output part of described force transducer (8) is successively by pressure signal amplifier (3) and data collecting instrument (5) input computing machine (6).
3. the transient impact method pick-up unit that comes to nothing under the structural panel according to claim 2, it is characterized in that: described exciting device (2) is the driver of exciting force quantification, comprise support (27), shell (21), pull bar (20), guide pole (25) and tup (28), described shell (21) is arranged on the support (27), shell (21) is provided with upper end cover (22) and bottom end cover (23), described guide pole (25) is arranged in the shell (21) in mode moving up and down, pull bar (20) passes upper end cover (22) fixedlys connected with guide pole (25) upper end, and tup (28) passes bottom end cover (23) fixedlys connected with guide pole (25) lower end; Between guide pole (25) upper end and the upper end cover (22) force application spring (24) is set, between guide pole (25) lower end and the bottom end cover (23) return spring (26) is set; Described force transducer (8) is arranged on tup (28) lower end.
4. the transient impact method pick-up unit that comes to nothing under the structural panel according to claim 3 is characterized in that: described acceleration transducer (1) is close on the structural panel to be detected (7).
5. the transient impact method pick-up unit that comes to nothing under the structural panel according to claim 4 is characterized in that: described tup (28) lower end is provided with tup pad (29), and described force transducer (8) is arranged between tup pad (29) and tup (28) lower end.
6. one kind is utilized the method for coming to nothing under the transient impact method pick-up unit detection architecture panel that comes to nothing under the described structural panel of claim 1, it is characterized in that:
May further comprise the steps:
A. degree of will speed up sensor (1) is arranged on the structural panel to be detected (7), with exciting device (2) moment impact structural panel to be detected (7), record compact structure panel natural frequency or/and amplitude, and with natural frequency or/and amplitude value is stored to computing machine (6);
B. select sensing range and at least one check point is set at structural panel to be detected (7), to acceleration transducer (1) be set on the check point, utilize exciting device (2) moment impact structural panel to be detected (7), record the check point vibration frequency or/and amplitude, and with the natural frequency of compact structure or/and amplitude ratio.
7. the method for coming to nothing under the detection architecture panel according to claim 6, it is characterized in that: among the step a, described exciting device (2) is the driver of exciting force quantification, the force application spring of the driver of adjustment exciting force quantification and the rigidity of return spring make the maximum elastic force situation of force application spring lower ram only impact once check point.
8. the method for coming to nothing under the detection architecture panel according to claim 7 is characterized in that: among the step b, described check point evenly distributes on structural panel.
9. according to the method for coming to nothing under claim 6, the 7 or 8 described detection architecture panels, it is characterized in that: exciting device (2) is provided with force transducer (8), among step a and the step b, in moment impact structural panel to be detected (7), utilize force transducer (8) to record impulsive force numerical value, make the impulsive force quantification.
10. the method for coming to nothing under the detection architecture panel according to claim 7 is characterized in that: among step a and the step b, described acceleration transducer (1) adopts the mode of being close to be arranged on the structural panel to be detected (7).
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