CN204177715U - Based on the steel rust in concrete monitoring sensor of Lamb wave principle - Google Patents
Based on the steel rust in concrete monitoring sensor of Lamb wave principle Download PDFInfo
- Publication number
- CN204177715U CN204177715U CN201420659718.7U CN201420659718U CN204177715U CN 204177715 U CN204177715 U CN 204177715U CN 201420659718 U CN201420659718 U CN 201420659718U CN 204177715 U CN204177715 U CN 204177715U
- Authority
- CN
- China
- Prior art keywords
- piezoelectric ceramic
- lamb wave
- rectangular piezoelectric
- stalloy
- 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.)
- Active
Links
Landscapes
- Testing Resistance To Weather, Investigating Materials By Mechanical Methods (AREA)
Abstract
The utility model discloses a kind of steel rust in concrete monitoring sensor based on Lamb wave principle, comprise strip stalloy, four rectangular piezoelectric ceramic sheets and wire, the positive and negative two sides of often holding of strip stalloy is closely pasted with two rectangular piezoelectric ceramic sheets respectively, wherein two rectangular piezoelectric ceramic sheets of one end are as driver, when applying high-frequency narrow-band pulse voltage on rectangular piezoelectric ceramic sheet thickness direction, it produces Lamb wave and propagates in stalloy; Two rectangular piezoelectric ceramic sheets of one end are as sensor in addition, receive the Lamb wave transmitted from strip stalloy, judge steel disc corrosion situation according to Lamb wave signal characteristic, thus judge the corrosion situation of surrounding environment, structure or other objects.The utility model solves and is not destroying the monitoring realizing concrete reinforcing steel initial corrosion time and corrosion degree under the microenvironment of concrete reinforcing steel surface, and the signal that sensor receives is simple and easy to process.
Description
Technical field
The utility model belongs to civil engineering works structure health monitoring, reinforced concrete structure durability field, is specifically related to a kind of steel rust in concrete monitoring sensor based on Lamb wave principle.
Background technology
One of the corrosion of Steel Bars in Concrete Structure is the normal use and the permanance that affect engineering structure, and then the key factor causing structural failure.Therefore, people wish can the corrosion ambient conditions of solution structure, or before structure havoc, just monitor the corrosion state of concrete reinforcing steel, and carries out early warning, makes to lose and is down to minimum or carried out necessary remedial measures before destroying.
The method of monitoring corrosion has a variety of, and the method such as monitoring steel bar corrosion can be divided into physical method and chemical method.Physical has resistance probe method and optical fiber sensing method, and the former adopts a probe identical with structural reinforcement material, is embedded to by probe in xoncrete structure, the change of Real-Time Monitoring probe resistance, infers the speed of steel bar corrosion and the degree of corrosion.And reinforcement in concrete can directly directly use as probe by the method, carries out Real-Time Monitoring, determine its corrosion rate to reinforcing bar.Optical fiber sensing method mainly produces strain due to optical fiber affected by force, and interface also changes thereupon, and wavelength, phase place, frequency, polarization that at this moment photon is propagated in a fiber all can change.Fibre Optical Sensor corrosion resistant and good endurance, antijamming capability are strong, and Fibre Optical Sensor can carry out space continuity monitoring.But optical fiber sensing technology due to technological requirement very high, cost is high, and the theoretical shortcoming such as immature of its relevant monitoring significantly limit the application of optical fiber sensing technology.Chemical method has cell potential method, linear polarization method and AC impedance method etc.The technical know-how of half-cell prtential method is the most ripe; by monitoring the change of the electromotive force of rebar surface; compare the state that just can judge corrosion; and this process is just equivalent to a chemical cell; so be called half-cell prtential method; but the method can not obtain the corrosion rate of reinforcing bar, and when cover to reinforcement is thicker, potential diagram is inaccurate.Linear polarization method can rusting rate near Quick Measurement metal, utilizes the relation that there is approximately linear between the polarization current of additional electrodes near corrosion of metal point and the polarized potential of metal, measures transient state rusting rate.The method not easily realizes long-time embedded on-line monitoring, and is subject to many factors disturbance due to polarization resistance and current potential, can not judge the corrosion state that reinforcing bar is definite.AC impedence method sends one section of small electric current to complex, measurement target system is to the reaction of this section of Weak current, by the exchange current spectrum measured, then compare exchange current spectrum and obtain concrete corrosion parameter, although the method is a kind of dynamic measuring method, but because its surveying instrument is very expensive, do not meet and save economic condition.And measure and can not complete in a short time, time span is of a specified duration, measures the data obtained amount large, comparatively large by ectocine, late time data process is quite difficult, is not suitable for field survey etc. shortcoming.
Lamb wave belongs to the supersonic guide-wave propagated in thin-slab construction, domestic at present also have research based on the monitoring steel bar corrosion method of ultrasonic guided wave technique, but the method is the reinforcing bar for full-scale length, it is not a kind of product sensor, time in for concrete, there is guided wave signals to leak, the weak point that the guided wave signals that sensor receives is faint and complicated, is difficult to be applied in Practical Project.In addition, reinforcing bar is solid cylinder, and the guided wave propagated in reinforcing bar is in available frequency range mode very many (nearly more than ten mode), and signal can be more complicated." prestressing technique " (2014, No.2) publish an article " steel reinforced concrete erosion damage ultrasonic guided wave signals wavelet analysis and evaluation " relate to and a kind ofly directly on reinforcing bar, excite guided wave and carry out the method for defects detection, because the length of reinforcing bar in engineering structure is very long, and guided wave modal is complicated in reinforcing bar, the signal that concrete existence also can make sensor receive is more complicated, and therefore distance practical engineering application still has certain gap.
Summary of the invention
For overcoming above-mentioned the deficiencies in the prior art, the purpose of this utility model is to provide a kind of steel rust in concrete monitoring sensor based on Lamb wave principle.
The technology that the utility model adopts is as follows: a kind of steel rust in concrete monitoring sensor based on Lamb wave principle, comprise strip stalloy and four rectangular piezoelectric ceramic sheets, the positive and negative two sides of often holding of strip stalloy is closely pasted with two rectangular piezoelectric ceramic sheets respectively, and the positive and negative electrode wire of each rectangular piezoelectric ceramic sheet picks out; Wherein two rectangular piezoelectric ceramic sheets of one end are as driver, and when at rectangular piezoelectric ceramic sheet thickness direction, i.e., when two wide area surface up and down of rectangular piezoelectric ceramic sheet apply high-frequency narrow-band pulse voltage, it produces Lamb wave and propagates in stalloy; Two rectangular piezoelectric ceramic sheets of one end are as sensor in addition, receive the Lamb wave transmitted from strip stalloy, judge steel disc corrosion situation according to Lamb wave signal characteristic, thus judge the corrosion situation of surrounding environment, structure or other objects.Wherein piezoelectric patches electrode surface be connected wire etc. before burying underground, need to do preservative treatment, prevent corrosion.
The utility model also has following technical characteristic: two, same one end piezoelectric actuator of described strip stalloy is when carrying out high-frequency narrow-band pulse excitation, the voltage applied is antisymmetry, namely respectively using the one side being pasted on steel disc of these two piezoelectric patches as negative pole, simultaneously apply positive voltage at another side.
The stalloy that the utility model adopts is more responsive to corrosion, and corrosion more easily makes stalloy produce the defects such as hole, thus the guided wave signals that the piezoelectric ceramic piece of other one end is received change is more obvious.Identical with stalloy as two of driver piezoelectric ceramic piece width in the utility model, be pasted on the tow sides of strip stalloy with one end respectively.During excitation, the voltage applied two piezoelectric patches is antisymmetry, and such two piezoelectric patches can produce antisymmetric acting force to stalloy simultaneously.Under antisymmetry acting force, the symmetrical mode (S mode) of Lamb wave is not energized, and only has antisymmetry mode (A mode) to be energized.Receive only the guided wave signals of an antisymmetry mode like this as the piezoelectric ceramic piece of sensor, be simple and easy to analyze.The utility model can judge the corrosion situation of strip stalloy according to the Lamb wave signal that piezoelectric ceramic piece receives, and analyzes further and judges that environment residing for it can cause the situation of structure corrosion.As being placed in concrete, the corrosion situation of reinforcement in concrete can be judged; It is made by material identical with hardware, and puts together with hardware, the corrosion situation of hardware can be judged.
The utility model mainly solves and is not destroying the monitoring realizing concrete reinforcing steel initial corrosion time and corrosion degree under the microenvironment of concrete reinforcing steel surface.The Lamb wave signal of stalloy used only has an antisymmetry mode in available frequency band, and the signal that sensor receives is simple and easy to process.
Accompanying drawing explanation
Fig. 1 is the vertical view of the corrosion sensor structural representation based on Lamb wave principle;
Fig. 2 is the outboard profile of the corrosion sensor structural representation based on Lamb wave principle; Wherein, 1, stalloy, 2, piezoelectric ceramic piece positive electrode, 3, the negative electrode of piezoelectric ceramic piece, 4, piezoelectric ceramic piece.
Fig. 3 is the dispersion curve of the Lamb wave antisymmetry mode (A mode) propagated in corrosion sensor metal foil steel disc used;
Fig. 4 is the signal contrast having non-corroding using this corrosion sensor to record, and corrosion is the square defect of the 0.6mm × 0.6mm of simulation, the narrow band signal of excitation employing five crest, and centre frequency is 800kHz, and maximum voltage is 200V;
Embodiment
Illustrate below and the utility model be described further:
embodiment 1
A kind of corrosion sensor based on Lamb wave principle, comprise strip stalloy (length 100mm, thickness 1mm, width 16mm), two rectangular piezoelectric ceramic sheet (length 6mm, width 16mm, thickness 0.5mm) and electrode cable, two rectangular piezoelectric ceramic sheets are pasted on stalloy two ends respectively, are connected with stalloy is firm with epoxide-resin glue or 502 glue etc.The negative electrode of piezoelectric ceramic piece turns over to the same surface of positive electrode, is picked out by positive and negative electrode, for connecting driving voltage or receiver voltage signal with copper conductor; Wherein two piezoelectric ceramic pieces of one end are as driver, when applying antisymmetric high-frequency narrow-band pulse voltage on the thickness direction of two piezoelectric ceramic pieces simultaneously, its generation zeroth order antisymmetry mode (
a 0) Lamb wave propagate in stalloy, run into corrosion produce defect time, the amplitude of guided wave can reduce.The piezoelectric ceramic piece of one end can receive the guided wave transmitted from stalloy in addition, and guided wave is converted to voltage signal by piezoelectric patches, picks out with electrode, and oscillograph or data acquisition system can be used to arrive.Analyze the time of origin of the difference in magnitude of the guided wave signals recorded before and after corrosion, can judge concrete reinforcing steel or other treat the geodesic structure initial corrosion time, analyze the rate of change of not guided wave signals difference in magnitude in the same time, can judge reinforcing bar or other treat the rusting rate of geodesic structure, analyze guided wave signals difference in magnitude also to compare with test findings, can judge reinforcing bar or other treat the corrosion degree of geodesic structure.
Claims (2)
1. the steel rust in concrete monitoring sensor based on Lamb wave principle, comprise strip stalloy, four rectangular piezoelectric ceramic sheets and wire, it is characterized in that: the positive and negative two sides of often holding of strip stalloy is closely pasted with two rectangular piezoelectric ceramic sheets respectively, and the positive and negative electrode wire of each rectangular piezoelectric ceramic sheet picks out; Wherein two rectangular piezoelectric ceramic sheets of one end are as driver, and when applying high-frequency narrow-band pulse voltage on rectangular piezoelectric ceramic sheet thickness direction, it produces Lamb wave and propagates in stalloy; Two rectangular piezoelectric ceramic sheets of one end are as sensor in addition, receive the Lamb wave transmitted from strip stalloy.
2. a kind of steel rust in concrete monitoring sensor based on Lamb wave principle according to claim 1, it is characterized in that: described strip stalloy with two, one end piezoelectric actuator when carrying out high-frequency narrow-band pulse excitation, the voltage applied is antisymmetry, namely respectively using the one side being pasted on steel disc of these two piezoelectric patches as negative pole, simultaneously apply positive voltage at another side.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420659718.7U CN204177715U (en) | 2014-11-07 | 2014-11-07 | Based on the steel rust in concrete monitoring sensor of Lamb wave principle |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420659718.7U CN204177715U (en) | 2014-11-07 | 2014-11-07 | Based on the steel rust in concrete monitoring sensor of Lamb wave principle |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN204177715U true CN204177715U (en) | 2015-02-25 |
Family
ID=52566520
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201420659718.7U Active CN204177715U (en) | 2014-11-07 | 2014-11-07 | Based on the steel rust in concrete monitoring sensor of Lamb wave principle |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN204177715U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104406901B (en) * | 2014-11-07 | 2017-02-01 | 北京奥科瑞检测技术开发有限公司 | Concrete internal steel bar corrosion monitoring sensor based on Lamb wave principle |
-
2014
- 2014-11-07 CN CN201420659718.7U patent/CN204177715U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104406901B (en) * | 2014-11-07 | 2017-02-01 | 北京奥科瑞检测技术开发有限公司 | Concrete internal steel bar corrosion monitoring sensor based on Lamb wave principle |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104406901B (en) | Concrete internal steel bar corrosion monitoring sensor based on Lamb wave principle | |
| CN103852492B (en) | Pumping of prostressed duct density monitoring method based on piezoelectric ceramics | |
| ElBatanouny et al. | Acoustic emission monitoring for assessment of prestressed concrete beams | |
| Xu et al. | Active interface debonding detection of a concrete-filled steel tube with piezoelectric technologies using wavelet packet analysis | |
| Gonzalez et al. | On-site determination of corrosion rate in reinforced concrete structures by use of galvanostatic pulses | |
| CN103940893B (en) | Device and method for monitoring corrosion defects of anchorage section of stay rope | |
| CN105158582A (en) | Variable-interval interdigitated adjacent capacitive sensor | |
| CN103557973B (en) | Existing structure prestress in situ detection system and method | |
| CN103592529A (en) | Method for evaluating insulation aging of XLPE (cross linked polyethylene) cable based on low-temperature pulse | |
| CN102288533A (en) | Device and method for detecting corrosion of conductor of grounding grid of power system based on SH0 (horizontal shear) wave | |
| US9176108B2 (en) | Method and device for measuring corrosion metal loss | |
| Lei et al. | An automatic extraction algorithm for measurement of installed rock bolt length based on stress wave reflection | |
| CN106855539A (en) | A kind of anchor rod nondestructive testing method and equipment based on stress wave | |
| Rashidi et al. | Assessment of the overall condition of bridge decks using the Jensen-Shannon divergence of NDE data | |
| CN103412056A (en) | Acoustic emission wave mode separation method based on double sensors for plate-like structure | |
| CN110095336A (en) | A kind of online sound emission of tank bottom stress corrosion-electrochemistry Collaborative experiment device | |
| CN102841143A (en) | Method for detecting corrosion of grounded grid circular steel bar based on lateral loading of piezoelectric sensors | |
| CN204177715U (en) | Based on the steel rust in concrete monitoring sensor of Lamb wave principle | |
| CN209961662U (en) | Corrosion on-line monitoring device | |
| CN105548360B (en) | Suspension cable corrosion combined monitoring method based on stress concentration and supersonic guide-wave | |
| CN204154619U (en) | Based on the corrosion sensor of supersonic guide-wave principle | |
| CN201945546U (en) | Portable reinforced concrete corrosion measuring instrument | |
| CN210487468U (en) | Device for monitoring width of concrete tensile crack and automatically positioning area | |
| Fares et al. | Estimation of water content gradient and concrete durability indicators using capacitive and electrical probes | |
| Bayane et al. | Acoustic emission and ultrasonic testing for fatigue damage detection in a RC bridge deck slab |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |