CN103076397B - The fine motion method of testing of civil engineering work panel structure damage check and system - Google Patents

The fine motion method of testing of civil engineering work panel structure damage check and system Download PDF

Info

Publication number
CN103076397B
CN103076397B CN201210567531.XA CN201210567531A CN103076397B CN 103076397 B CN103076397 B CN 103076397B CN 201210567531 A CN201210567531 A CN 201210567531A CN 103076397 B CN103076397 B CN 103076397B
Authority
CN
China
Prior art keywords
wave detector
damage
mode
civil engineering
vibration
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.)
Expired - Fee Related
Application number
CN201210567531.XA
Other languages
Chinese (zh)
Other versions
CN103076397A (en
Inventor
车爱兰
程成
陈梦
刘超
冯少孔
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shanghai Jiaotong University
Original Assignee
Shanghai Jiaotong University
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Shanghai Jiaotong University filed Critical Shanghai Jiaotong University
Priority to CN201210567531.XA priority Critical patent/CN103076397B/en
Publication of CN103076397A publication Critical patent/CN103076397A/en
Application granted granted Critical
Publication of CN103076397B publication Critical patent/CN103076397B/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Abstract

The present invention discloses a kind of fine motion method of testing of civil engineering work panel structure damage check, first according to structure build by laying bricks or stones and the feature such as damage arranges multiple wave detector in surfaces of wall, gather micro-tremor signal by wave detector and recording unit.Natural frequency and the natural mode of vibration of structure is obtained by mathematical analysis.According to the data such as original design and construction, establish and improve structural finite element model (finite difference simulator), carry out eigenwert calculating, obtain its dynamic response such as natural frequency and natural mode of vibration parameter.Relatively the natural frequency of computation model and actual measurement structure and natural mode of vibration, evaluate mutated site and the Sudden Changing Rate (loss of rigidity) of response, positions and quantitatively to damage.Corresponding system is also provided.Present device is simple, efficiency is high, on structure not damaged, analysis theories is rigorous, analytical approach precision is high, not by the impact of structural damage degree and complicacy, for civil engineering structure damage check provides a kind of brand-new method.

Description

The fine motion method of testing of civil engineering work panel structure damage check and system
Technical field
What the present invention relates to is that a kind of Structural Engineering detects, and the particularly Non-Destructive Testing of panel structure, belongs to Structural Engineering field.
Background technology
Structure, in the Service Environment of complexity, by being subject to the impact of all effects in load, naturally weathering and various sudden external factor, is faced with damage and damage accumulation problem.The usability of structure will certainly be caused to reduce for the accumulation of these damages or recurring structure destroys.Therefore, be ensure the safety of structure, need the method setting up detecting and identifying structural damage, so as can detecting structure damage as soon as possible appearance, there is the position of damage and the degree of damage, structure is repaired in real time, the sexual behavior that averts a calamity thus generation.In recent years along with the expansion that China's large-scale basis is built, the complicated civil engineering structure that maximizes constantly increases, and accident resulting from poor quality of projects also happens occasionally.In addition, the model of Chinese ancient architecture not still our east ancient architectural art, and be the historical and cultural heritage of whole mankind's preciousness.Therefore there is complicated lesion for large and complex structure and structure body, the intricate and roundabout civil engineering structure of display form, need to set up the method avoided structure generation harmful effect itself and detection and Identification structural damage quickly and easily.
Nearly two during the last ten years, utilizes non-destructive method to carry out detection architecture and whether there is damage, and to damage position with assess become domestic and international academia, engineering circles very pay close attention to and study enliven field.Wherein utilize the change of structural dynamic characteristic to carry out the technique and method of the overall damage check of structure, have signal to be easy to extract, detector can be installed to the advantages such as the unsuitable close position of people.Fine motion test does not need artificially to apply focus, and its disturbance source is the small vibrations of the earth depths, on structure itself almost without impact; Fine motion testing apparatus is in addition light and handy, simple to operate, is convenient to apply in large and complex structure.The vibration characteristics (eigenwert, ratio of damping, mode of oscillation etc.) of building structure can be inferred well by certain analysis means.Therefore, in theory, by do not damage model and actual measurement damaged structure kinetic parameter with can detection architecture mechanical property and whether have damage exist.The civil engineering work panel structure damage detecting method of fine motion measuring technology and system is utilized to invent based on above characteristic and a large amount of experiments just.The research and development of this technology are that civil structure damage check provides that a kind of precision is good, efficiency is high, means quickly and easily, significant.
Summary of the invention
The invention provides a kind of fine motion method of testing and system of civil engineering structure damage check, be mainly used in the panel structure internal injury state Non-Destructive Testings such as brick, concrete.It will be appreciated by those skilled in the art that fine motion method of testing and the system of damage check provided by the present invention not only can be applicable to civil engineering work panel structure, other structure can also be applicable to, belong to protection scope of the present invention equally.
According to an aspect of the present invention, a kind of fine motion method of testing of civil engineering work panel structure damage check is provided, comprises the steps:
Step 1: building by laying bricks or stones and injury characteristic according to structure, lays wave detector comprehensively, and wave detector position is referred to as check point;
Step 2: after being connected with recording unit by wave detector, records the collection waveform of half an hour more than;
Step 3: by Fast Fourier Transform (FFT) (FastFourierTransform-FFT) extract recorded in frequency characteristic;
Step 4: directly utilize FFT spectral characteristic curve, the amplitude extracting remarkable peak value and its correspondence is as each rank natural frequency of structure and natural mode of vibration;
Step 5: according to structure original design and construction information, establish and improve structural computational model, carries out eigenwert calculating, the dynamic response parameters such as the natural frequency of acquisition structure and natural mode of vibration.
Step 6: to fine motion test natural mode of vibration and compute mode distribution carry out unified physics amount data normalization process or without the process of guiding principle amount;
Step 7: compare computation model and natural frequency and the natural mode of vibration of surveying structure, evaluate response mutated site, damage is positioned.
Preferably, also to occur a lot of preferred after also comprising the steps:, what meaning? Essential Terms?
Step 8: system on-the-spot test object being reduced to a n degree of freedom, calculates damage stiffness K by following formula one obvand to be calculated by formula two and do not damage stiffness K cal, definition loss of rigidity is be deployed in the distribution plan of structural plan, the degree of injury distribution of structure can be obtained,
[ K obv ] - [ φ obv ] - T diag [ ω 1 2 , ω 2 2 , . . . , ω n 2 ] [ φ obv ] - 1 Formula one
[ K cal ] - [ φ cal ] - T diag [ ω 1 2 , ω 2 2 , . . . , ω n 2 ] [ φ cal ] - 1 Formula two
Wherein, ω ithe i-th rank eigenwert, i=1,2 ..., n, ω iby testing the damaged structure proper vector obtained, ω iby the non-damaged structure proper vector calculated.
Preferably, described computation model is finite element model, and described compute mode is FEM (finite element) calculation mode.
Preferably, described computation model is finite difference simulator, and described compute mode is finite difference formulations mode.
Preferably, described wave detector comprises simple component wave detector and/or three-component seismometer, and simple component wave detector is for gathering the response wave shape of a direction, and three-component seismometer is for gathering the response wave shape in three directions.
Preferably, described wave detector is the moving-coil speed-type elastic wave exploration wave detector of natural frequency 1.0 ~ 100Hz.
According to another aspect of the present invention, a kind of fine motion test macro of civil engineering work panel structure damage check is also provided, comprise the data acquisition module, data analysis module, Numerical Simulation Module and the data visualization processing module that are connected successively, Numerical Simulation Module is connection data acquisition module also, data visualization processing module is connection data analysis module also, wherein:
Described data acquisition module comprises several wave detector and registering instrument;
Described data analysis module is used for waveform processing, Fast Fourier Transform (FFT) and natural frequency and natural mode of vibration analysis;
Described Numerical Simulation Module calculates data for adopting finite element or finite difference method;
Described data visualization processing module is used for generating and display original waveform figure, various intermediate processing results figure and final process result figure.
Preferably, described wave detector is the moving-coil speed-type elastic wave exploration wave detector of natural frequency 1.0 ~ 100Hz, described wave detector comprises simple component wave detector and/or three-component seismometer, simple component wave detector is for gathering the response wave shape of a direction, and three-component seismometer is for gathering the response wave shape in three directions.
Preferably, the low cut-off frequency of described registering instrument is lower than 1.0Hz, and high cut-off frequency, higher than 5kHz, is elastic wave exploration digital seismograph.
Preferably, the set-up mode of described wave detector is for be fixed on surfaces of wall with equipment wave detector; First being characterised in that of Analysis of Spectrum of described data analysis module be converted to frequency domain signal the clock signal of record by fast fourier transform, then directly reads each excellent frequency and amplitude; Then the direct amplitude corresponding by each excellent frequency is converted to structure height-amplitude curve, then carries out without the process of guiding principle amount to amplitude, obtains each rank natural mode of vibration of structure height-amplitude ratio curve as structure; Described Numerical Simulation Module adopts the eigenwert theory of computation, the eigenwert of carrying out two dimension and/or three-dimensional structure calculates, obtain natural frequency and the natural mode of vibration of non-damage structure, carry out without the process of guiding principle amount to natural mode of vibration, obtain each rank natural mode of vibration of non-damage structure height-amplitude ratio curve as structure.
The present invention utilizes the change of structural dynamic characteristic to contain more damage information to the location and the natural mode of vibration of quantitative evaluation, particularly structure of carrying out the damage of structure entirety, utilize natural mode of vibration to position structural damage and quantitative evaluation more accurate.By comparing the natural mode of vibration of actual measurement structure and not damaging the natural mode of vibration evaluation structure internal injury degree of model, there is the features such as method simple, intuitive, precision is good, efficiency is high, cost is low.
Compared with prior art, the present invention at least comprises following beneficial effect:
(1) use multiple wave detector to form geophone group, fully hold the overall damage status of structure.
(2) need not explosive source, directly gather the small vibrations of the earth, structure is had no adverse effects.
(3) frequency characteristic of record data is obtained by Fast Fourier Transform (FFT) (FFT).
(4) by definition loss of rigidity, damage quantitative evaluation is carried out to one-piece construction.
Accompanying drawing explanation
By reading the detailed description done non-limiting example with reference to the following drawings, other features, objects and advantages of the present invention will become more obvious:
Fig. 1 is civil engineering work panel structure damage check fine motion method schematic diagram;
Fig. 2 is wave detector scheme of installation
Fig. 3 is measured waveform figure;
Fig. 4 is Fast Fourier Transform (FFT) result figure;
Fig. 5 is structure height-amplitude curve;
Fig. 6 is structure height-amplitude ratio curve;
Fig. 7 is three-dimensional finite element model figure;
Fig. 8 is not for damage model modal graph;
Fig. 9 is damage reason location sectional view;
Figure 10 is damage quantitative sectional view.
Embodiment
Below embodiments of the invention are elaborated.The present embodiment is implemented premised on technical solution of the present invention, give detailed embodiment and concrete operating process, but protection scope of the present invention is not limited to following embodiment.
In the present embodiment, detected object is the brick wall body structure that thickness is about 0.75m, and its building method edge is highly different and existing faulted condition is complicated, the overall damage position of main detection architecture and degree of injury.As depicted in figs. 1 and 2, specifically implement as follows:
First build feature and degree of impairment by laying bricks or stones according to structure and from the teeth outwards multiple wave detector (two components, perpendicular to body of wall and be parallel to body of wall) is set in differing heights varying level position.Wave detector uses the moving-coil speed-type wave detector (elastic wave exploration wave detector) of natural frequency 4.5Hz; Method to set up adopts and is fixed on surface of wall by equipment; Registering instrument adopts common exploration seismograph and turns off high cut-off frequency wave filter.
After wave detector is connected with registering instrument, get rid of the interference of human activity near test point, various power source as far as possible.Sampling interval 0.004s is set, continuous acquisition 150min.The oscillogram of the data collected as shown in Figure 3.
First filter the radio-frequency component of more than 10Hz to eliminate various artificial and dynamic interference around with digital filtering during data processing, from 150min microtremor observation data, then choose the stable 10 groups of data of waveform, often organize data time band 60s.
First clock signal, frequency domain signal is transformed to by fast fourier transform to the often group data chosen during spectrum analysis, calculate the fourier spectra of measured data, Hanning window is added 10 times to fourier spectra, after smoothingization (Band=is about 0.1Hz), be weighted on average to the fourier spectra of 10 groups of data, just obtain the fourier spectra curve shown in Fig. 4.The amplitude reading peak value in curve and correspondence, as the excellent frequency of measured data and amplitude, is directly converted to amplitude corresponding for each excellent frequency the corresponding relation of the structure height shown in Fig. 5 and amplitude.Each height amplitude and foot observation station amplitude are divided by and after minimum portion measuring point transverse axis is moved at 0, obtain the corresponding relation of the structure height shown in Fig. 6 and amplitude ratio.
Set up the non-damage structure three-dimensional model shown in Fig. 7 according to data such as design and constructions, carry out eigenwert calculating, obtain the non-damage structure natural mode of vibration distribution plan shown in accompanying drawing 8.
First contrast test result and 1,2,3 rank modal distribution of corresponding result of calculation, obtain modal distribution change location and variable quantity, be deployed in the distribution plan of structural plan, obtains the damage position distribution of the structure shown in Fig. 9.
Each for structure test zone is reduced to the system of 3 degree of freedom by this test.Rigidity k1 in system, k2, k3 are unknown quantity, and quality m1, m2, m3 are known constant, and eigenwert ω and vibration shape Y is known test result, by eigenwert calculate ( k 1 = s 1 Y 11 + s 3 Y 31 + s 2 Y 21 Y 11 k 2 = s 3 Y 31 + s 2 Y 21 Y 31 - Y 11 k 3 = s 3 Y 31 Y 31 - Y 21 ) rigidity k1, k2, k3 can be obtained, wherein s 1 0 0 0 s 2 0 0 0 s 3 = ω 2 [ M ] , [M] is mass matrix m 1 0 0 0 m 2 0 0 0 m 3 , Y is the amplitude ratio of structure, Y = Y 11 Y 21 Y 31 .
For the fine motion test natural mode of vibration after normalized and dimensional Finite Element modal distribution, calculate damage stiffness K by following formula one obv, calculated by formula two and do not damage stiffness K cal, definition loss of rigidity is be deployed in the distribution plan of structural plan, obtain the structural damage degree distribution shown in Figure 10.
[ K ubv ] = [ φ ubv ] - T diag [ ω 1 2 , ω 2 2 , . . . , ω n 2 ] [ φ ubv ] - 1 Formula one
[ K cul ] = [ φ cul ] - T diag [ ω 1 2 , ω 2 2 , . . . , ω n 2 ] [ φ cul ] - 1 Formula two
Wherein, ω ithe i-th rank eigenwert, i=1,2 ..., n, ω iby testing the damaged structure proper vector obtained, ω iby the non-damaged structure proper vector calculated.
Data visualization process mainly generates and shows structure height-amplitude curve, structure height-amplitude ratio curve, construction damage positioning sectional view and the quantitative sectional view of structural damage (Fig. 5 ~ 6,9 ~ 10).
Above specific embodiments of the invention are described.It is to be appreciated that the present invention is not limited to above-mentioned particular implementation, those skilled in the art can make various distortion or amendment within the scope of the claims, and this does not affect flesh and blood of the present invention.

Claims (8)

1. a fine motion method of testing for civil engineering work panel structure damage check, is characterized in that, comprise the steps:
Step 1: building by laying bricks or stones and injury characteristic according to structure, lays wave detector comprehensively, and wave detector position is referred to as check point; Particularly, in civil engineering work surfaces of wall, differing heights varying level position arranges multiple wave detector, and set-up mode adopts two componentwises, perpendicular to body of wall and be parallel to body of wall;
Step 2: after being connected with recording unit by wave detector, records the collection waveform of half an hour more than; Sampling interval 0.004s is set, continuous acquisition 150min;
Step 3: first filter the radio-frequency component of more than 10Hz to eliminate various artificial and dynamic interference around with digital filtering during data processing, then choose the stable 10 groups of data of waveform from 150min microtremor observation data, often organize data time band 60s; By Fast Fourier Transform (FFT) extract recorded in frequency characteristic;
Step 4: directly utilize FFT spectral characteristic curve, the amplitude extracting remarkable peak value and its correspondence is as each rank natural frequency of structure and natural mode of vibration;
Step 5: according to structure original design and construction information, establish and improve structural computational model, carries out eigenwert calculating, obtains natural frequency and these dynamic response parameters of natural mode of vibration of structure;
Step 6: to fine motion test natural mode of vibration and compute mode distribution carry out unified physics amount data normalization process or without the process of guiding principle amount;
Step 7: compare computation model and natural frequency and the natural mode of vibration of surveying structure, evaluate response mutated site, damage is positioned;
Step 8: system on-the-spot test object being reduced to a n degree of freedom, calculates damage stiffness K by following formula one obvand to be calculated by formula two and do not damage stiffness K cal, definition loss of rigidity is be deployed in the distribution plan of structural plan, the degree of injury distribution of structure can be obtained,
Wherein, ω ithe i-th rank eigenwert, i=1,2 ..., n, ω iby testing the damaged structure proper vector obtained, ω iby the non-damaged structure proper vector calculated.
2. the fine motion method of testing of civil engineering work panel structure damage check according to claim 1, is characterized in that, described computation model is finite element model, and compute mode is FEM (finite element) calculation mode.
3. the fine motion method of testing of civil engineering work panel structure damage check according to claim 1, is characterized in that, described computation model is finite difference simulator, and compute mode is finite difference formulations mode.
4. the fine motion method of testing of civil engineering work panel structure damage check according to claim 1, it is characterized in that, described wave detector comprises simple component wave detector and/or three-component seismometer, simple component wave detector is for gathering the response wave shape of a direction, and three-component seismometer is for gathering the response wave shape in three directions.
5. the fine motion method of testing of civil engineering work panel structure damage check according to claim 1, is characterized in that, described wave detector is the moving-coil speed-type elastic wave exploration wave detector of natural frequency 1.0 ~ 100Hz.
6. the fine motion test macro of a civil engineering work panel structure damage check, it is characterized in that, comprise the data acquisition module, data analysis module, Numerical Simulation Module and the data visualization processing module that are connected successively, Numerical Simulation Module is connection data acquisition module also, data visualization processing module is connection data analysis module also, wherein:
Described data acquisition module comprises several wave detector and registering instrument;
Described data analysis module is used for waveform processing, Fast Fourier Transform (FFT) and natural frequency and natural mode of vibration analysis;
Described Numerical Simulation Module calculates data for adopting finite element or finite difference method;
Described data visualization processing module is used for generating and display original waveform figure, various intermediate processing results figure and final process result figure;
The set-up mode of described wave detector is for be fixed on surfaces of wall with equipment wave detector, particularly, in civil engineering work surfaces of wall, differing heights varying level position arranges multiple wave detector, and set-up mode adopts two componentwises, perpendicular to body of wall and be parallel to body of wall; First being characterised in that of Analysis of Spectrum of described data analysis module be converted to frequency domain signal the clock signal of record by fast fourier transform, then directly reads each excellent frequency and amplitude; Then the direct amplitude corresponding by each excellent frequency is converted to structure height-amplitude curve, then carries out without the process of guiding principle amount to amplitude, obtains each rank natural mode of vibration of structure height-amplitude ratio curve as structure; Described Numerical Simulation Module adopts the eigenwert theory of computation, the eigenwert of carrying out two dimension and/or three-dimensional structure calculates, obtain natural frequency and the natural mode of vibration of non-damage structure, carry out without the process of guiding principle amount to natural mode of vibration, obtain each rank natural mode of vibration of non-damage structure height-amplitude ratio curve as structure.
7. the fine motion test macro of civil engineering work panel structure damage check according to claim 6, it is characterized in that, described wave detector is the moving-coil speed-type elastic wave exploration wave detector of natural frequency 1.0 ~ 100Hz, described wave detector comprises simple component wave detector and/or three-component seismometer, simple component wave detector is for gathering the response wave shape of a direction, and three-component seismometer is for gathering the response wave shape in three directions.
8. the fine motion test macro of civil engineering work panel structure damage check according to claim 6, is characterized in that, the low cut-off frequency of described registering instrument is lower than 1.0Hz, and high cut-off frequency, higher than 5kHz, is elastic wave exploration digital seismograph.
CN201210567531.XA 2012-12-24 2012-12-24 The fine motion method of testing of civil engineering work panel structure damage check and system Expired - Fee Related CN103076397B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201210567531.XA CN103076397B (en) 2012-12-24 2012-12-24 The fine motion method of testing of civil engineering work panel structure damage check and system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201210567531.XA CN103076397B (en) 2012-12-24 2012-12-24 The fine motion method of testing of civil engineering work panel structure damage check and system

Publications (2)

Publication Number Publication Date
CN103076397A CN103076397A (en) 2013-05-01
CN103076397B true CN103076397B (en) 2016-04-13

Family

ID=48152996

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201210567531.XA Expired - Fee Related CN103076397B (en) 2012-12-24 2012-12-24 The fine motion method of testing of civil engineering work panel structure damage check and system

Country Status (1)

Country Link
CN (1) CN103076397B (en)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103971018B (en) * 2014-05-23 2016-09-07 福州大学 Connection stiffness Forecasting Methodology based on vibration-testing
CN105738480A (en) * 2016-02-05 2016-07-06 武汉大学 Concrete gravity dam strong shock damaged part quick identification method based on frequency errors
CN106404914B (en) * 2016-08-26 2019-08-06 四川省建筑科学研究院 The structural damage of a kind of pair of Wooden Pagoda at Yingxian County and the test method of safe condition
CN108226399B (en) * 2018-01-23 2019-03-19 中冶建筑研究总院有限公司 A kind of beam-string structure damage combined recognising method based on modal parameter
CN108802203B (en) * 2018-06-20 2019-12-17 中国科学院声学研究所 rod-shaped member internal defect positioning method based on multi-mode technology

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20050072234A1 (en) * 2003-05-20 2005-04-07 Weidong Zhu System and method for detecting structural damage
CN101034053A (en) * 2007-02-13 2007-09-12 中国海洋大学 Structure damage diagnosis method based on modality information
CN102034021A (en) * 2010-11-29 2011-04-27 李惠 Integral and local information fusing method of structure health diagnosis

Also Published As

Publication number Publication date
CN103076397A (en) 2013-05-01

Similar Documents

Publication Publication Date Title
CN103076397B (en) The fine motion method of testing of civil engineering work panel structure damage check and system
Brownjohn et al. Ambient vibration re-testing and operational modal analysis of the Humber Bridge
CN104239736A (en) Structure damage diagnosis method based on power spectrum and intelligent algorithms
CN102506986B (en) Test system and method for mode and vibration of self-supporting tower and large-span power transmission tower
CN102004267B (en) Precision measurement system and method of seismic detector
CN106092479B (en) Slab and girder load identifies and the multi-function test stand of non-destructive tests
CN109357822A (en) A kind of quick test and evaluation method of bridge changed based on Vehicle-Bridge Coupling System time-varying dynamic characteristic
CN104537251A (en) Fan blade impulse load recognition method
Belfi et al. Horizontal rotation signals detected by “G-Pisa” ring laser for the M w= 9.0, March 2011, Japan earthquake
CN102661782B (en) Rapid measurement method and device of super-low-frequency vibration parameter quantity value
CN101701882B (en) Fast identification method of tower structure stiffness
Fu et al. Time-frequency analysis of seismic wave propagation across a rock mass using the discontinuous deformation analysis method
Ghayamghamian et al. On the characteristics of ground motion rotational components using Chiba dense array data
Calcina et al. Ambient vibration tests of an arch dam with different reservoir water levels: experimental results and comparison with finite element modelling
CN205843918U (en) Slab and girder load identification and the multi-function test stand of non-destructive tests
Kuang et al. Wind-induced response characteristics of a tall building from GPS and accelerometer measurements
CN203299172U (en) Fretting damage detection system for civil engineering wallboard structure
Budde et al. Impact Detection for a Fiberglass Composite Rotor Blade
CN103698088A (en) Testing method for asymmetric rigidity of turbonator rotating shaft
CN201859225U (en) Precision measuring system of seismic detector
Calcina et al. Vibration analysis of historic bell towers by means of contact and remote sensing measurements
Lin et al. 836. Bridge scour evaluation based on ambient vibration
Sözüer EFFECTS OF CURTAIN WALL FAÇADE ON THE DYNAMIC PROPERTIES OF A BUILDING
CN105911138A (en) Impact imaging method and system based on average response energy
Kawashima et al. Measurements of Unsteady Force Response on Airfoils with Arbitrarily Shaped Thickness due to Incident Large-Scale Turbulence

Legal Events

Date Code Title Description
PB01 Publication
C06 Publication
SE01 Entry into force of request for substantive examination
C10 Entry into substantive examination
GR01 Patent grant
C14 Grant of patent or utility model
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20160413

Termination date: 20181224

CF01 Termination of patent right due to non-payment of annual fee