CN201731984U - Wireless inclination based bridge structure deflection measurement system - Google Patents

Wireless inclination based bridge structure deflection measurement system Download PDF

Info

Publication number
CN201731984U
CN201731984U CN2010202724109U CN201020272410U CN201731984U CN 201731984 U CN201731984 U CN 201731984U CN 2010202724109 U CN2010202724109 U CN 2010202724109U CN 201020272410 U CN201020272410 U CN 201020272410U CN 201731984 U CN201731984 U CN 201731984U
Authority
CN
China
Prior art keywords
deflection
bridge
wireless
unit
inclination
Prior art date
Application number
CN2010202724109U
Other languages
Chinese (zh)
Inventor
喻言
欧进萍
Original Assignee
大连理工大学
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 大连理工大学 filed Critical 大连理工大学
Priority to CN2010202724109U priority Critical patent/CN201731984U/en
Application granted granted Critical
Publication of CN201731984U publication Critical patent/CN201731984U/en

Links

Abstract

The utility model discloses a wireless inclination based bridge structure deflection measurement system and method and belongs to the technical field of bridge structure measurement. The measurement system is characterized by comprising two wireless inclination sensors and a wireless data unit which are connected with a PC through serial ports, wherein the measurement system consists of an MEMS technology based inclination unit, an inclination collection unit, a wireless transmitting/receiving unit, and an energy module. A bridge deflection curve formula is constructed in consideration of a combined action of the self weight of a bridge structure and external loads; an inclination formula is resulted by differentiating the deflection formula; and unknown parameters of the formula are resulted by calculating an actually measured inclination so as to resulting a deflection value. The system overcomes defects present in conventional wire measurement systems and methods and is featured with high test accuracy, excellent stability, good real-time performance, correct calculation and the like; furthermore, the method is suitable for the measurement of deflection and deformation of a beam-like structure and has a good application prospect.

Description

Deflection of bridge structure measuring system based on wireless tilt
Technical field
The utility model belongs to the bridge structure field of measuring technique, relate to a kind of bridge structure monitoring deflection metrology system and method that is suitable for being applied in based on the wireless tilt acquisition system, specifically a kind of wireless sensor technology that utilizes carries out the structure measurement of dip angle, calculates measuring system and the method that obtains the structural deflection value again.
Background technology
Bridge is an ingredient important in the Modern Traffic transportation network, and it is carried out safety monitoring is very necessary.In the past mostly bridge monitoring was to estimate, now along with science and technology development, increasing monitoring instrument is used for bridge monitoring.By analysis to the bridge monitoring data, can understand the past and present working condition of bridge structure, predict the situation that it is following, and amount of deflection is an important monitoring parameter.Amount of deflection is to judge bridge vertical rigidity, structural bearing capacity and the of paramount importance technical parameter of structural integrity, is the important indicator that rating bridge, unsafe bridge transformation and new bridge are checked and accepted.If deflection of bridge span has surpassed the design margin of regulation, bridge has the danger of collapsing at any time, jeopardizes the people's life security, causes huge property loss.Therefore, the measurement to deflection of bridge span is quite necessary.
The method of measuring deflection of bridge span in recent years has many, the robot measurement method is measured as adopting, communicating pipe the photoelectricity level gauging, utilize the precision positioning technology of GPS to measure, utilize displacement transducer to measure etc.In the said method, the robot measurement method is measured amount of deflection, have characteristics such as high intelligence, rapidity, wide range and high precision, but cost is than higher; Communicating pipe photoelectricity level gauging amount of deflection, though have very high precision, implementation process complexity, implementation cycle are long; And the precision positioning technology of GPS implements, and cost is also expensive.Adopt the measurement of dip angle deflection of bridge span not need the in-site measurement benchmark to reach and not influenced by daylight, rain, mist etc., measurement range is bigger, can realize one dimension/two-dimensional measurement.The obliquity sensor chip is a kind of integrated chip, and its inside has modulation-demodulation circuit, utilizes this circuit that the conversion of signals that collects is become voltage signal, with signal extraction, changes into actual angle value by microprocessing unit.And along with the development of sensing technology, wireless communication technology and MEMS technology, wireless sensor technology has begun to the structure monitoring infiltration and has become the focus of this respect research.
According to material mechanics principle, be example with freely-supported bridge Fig. 1, because the amount of deflection and the load of beam are linear, obey the Hookean elasticity law, coefficient is relevant with the characteristics such as rigidity of material.The deformation effect that each load causes on the beam is incoherent each other, satisfies superposition law.Therefore load can be decomposed, calculate the deflection deformation that causes under the situation of the independent effect of each load.
Do not having under the extraneous load condition, when only considering the loading of bridge self gravitation, load is evenly distributed in the length range of bridge, and establishing the load intensity is q (N/m), and overall length of bridge is 1.Set up coordinate system, the equations of rotating angle that can try to achieve any point on the beam is,
θ = w ' = q 24 EI ( l 3 - 6 l x 2 + 4 x 3 ) - - - ( 1 )
BI is a constant, the bendind rigidity of expression beam, and E is the tension and compression elastic modulus, I is a moment of inertia.By formula 1 can be in the hope of the sag curve equation:
w = qx 24 EI ( l 3 - 2 l x 2 + x 3 ) - - - ( 2 )
Utilize above-mentioned fundamental formular, carry out transform operation and just can obtain deflection value.
Above-mentioned formula has only been considered the effect situation of bridge deadweight, obviously utilizes above-mentioned formula to carry out deflection metrology under the various states of bridge, because of not considering the external loads situation, measures inaccurate.
The utility model content
The utility model provides deflection of bridge structure measuring system and the computational accuracy high deflection of bridge structure measuring method based on wireless tilt of a kind of easy-to-install based on wireless tilt.
The technical solution of the utility model is as follows:
Measure wireless tilt sensor that amount of deflection adopted and acquisition system structure thereof as shown in Figure 2: a kind of deflection of bridge structure measuring system based on wireless tilt, comprise two wireless tilt sensor units, wireless data unit and computer unit, computer unit adopts serial mode to be connected with wireless data unit, and carries out radio communication with the wireless tilt sensor unit.Wherein the wireless tilt sensor unit comprises general inclination angle MEMS chip, inclination angle collecting unit, wireless transmit/receive units and energy module.Wireless data unit adopts the wireless universal module that has serial ports to realize; Computer unit comprises Calculation of Deflection unit and data display unit.Two wireless tilt sensor nodes are pre-loaded embedded capture program.
A kind of method of the deflection of bridge structure measuring system based on wireless tilt, at first measure the inclination data of bridge by the inclination angle collecting unit of wireless tilt sensor unit, the inclination data that the inclination angle collecting unit will be measured gained is converted to can carry out the data layout of serial communication and transfer to computer unit by wireless transmit/receive units, computer unit adopts the Calculation of Deflection formula to calculate amount of deflection, and the Calculation of Deflection formula is as follows:
With the freely-supported bridge is example, and wherein p is an external load, and q is the load intensity, and 1 is the beam total length, and EI is a constant, the bendind rigidity of expression beam, and E is the tension and compression elastic modulus, I is a moment of inertia.
Show as Fig. 1, can get by above-mentioned formula (1), (2):
θ max = ± q l 3 24 EI - - - ( 3 )
w max = w | x = l 2 = 5 ql 4 384 EI (maximal value obtains at the mid point of beam) (4)
When only considering external load, the distortion amount of deflection of bridge is analyzed.External load generally is that the vehicle that travels on the bridge etc. applies, and is little with respect to the deflection deformation that is caused by the bridge deadweight.Say that with regard to freely-supported beam type bridge the amount of deflection of span centre is a key point.Therefore with model simplification, load concentration to span centre, is calculated.External load P acts on span centre, and promptly during x=1/2, the deflection deformation that is produced by external load is a formula 5,6:
y = - px 12 EI ( 3 l 2 4 - x 2 ) 0 ≤ x ≤ l 2 - - - ( 5 )
y = - p 12 EI ( x 3 + 9 l 2 x 4 - 3 l x 2 - l 3 4 ) l 2 ≤ x ≤ l - - - ( 6 )
By superposition principle, the sag curve that bridge deadweight and external load produce is formula (7), (8):
y = - px 12 EI ( 3 l 2 4 - x 2 ) - qx 24 EI ( l 3 - 2 l x 2 + x 3 ) , Wherein 0 ≤ x ≤ l 2 - - - ( 7 )
y = - p 12 EI ( x 3 + 9 l 2 x 4 - 3 l x 2 - l 3 4 ) - qx 24 EI ( l 3 - 2 l x 2 + x 3 ) , Wherein l 2 ≤ x ≤ l - - - ( 8 )
Maximal value is got at the place at span centre:
y max = - l 3 48 EI ( p + 5 ql 8 ) - - - ( 9 )
Order Differentiate is carried out in formula (7), (8) gets the inclination angle equation,
y ' = ( 3 x 2 - 3 l 2 4 ) a + ( 6 l x 2 - l 3 - 4 x 3 ) b Wherein 0 ≤ x ≤ l 2 - - - ( 10 )
y ' = ( - 3 x 2 - 9 l 2 4 + 6 lx ) a + ( - l 3 + 6 l x 2 - 4 x 3 ) b Wherein l 2 ≤ x ≤ l - - - ( 11 )
Both sides are laid the wireless tilt sensor node respectively in spanning, record 2 inclination angle value.Substitution formula (10), (11), i.e. the equations of rotating angle of span centre both sides, the value that obtains unknown quantity a, b is substitution formula (7), (8) again, thereby obtain the deflection equation of both sides in the spanning, and said method is measured amount of deflection and is called two-point method.Can utilize least square method from this method, expand to multimetering.
The beneficial effects of the utility model are to select for use the sensor chip based on the MEMS technology to come induced signal.Wireless data unit has been reserved serial ports.MEMS chip, inclination data collection and wireless transmit/receive units form the wireless tilt sensor.Wireless data unit and computing machine link and finish the reception of inclination data.Only need to measure 2 angles and just can extrapolate deflection value.Algorithm computation that the computer program utilization the utility model proposes and demonstration amount of deflection.
Based on Calculation of Deflection method that the utility model proposes and wireless tilt sensor measuring system, wireless sensor node is easy to assembling and disassembling, save lays the expense of lead and saves the set-up time, and calculates characteristics such as amount of deflection is accurate and determined its wide prospect and practical value.
Description of drawings
Fig. 1 is the utility model freely-supported bridge mechanical model synoptic diagram.
Fig. 2 is the deflection metrology system based on the wireless tilt sensor of the present utility model.
Fig. 3 is the sag curve under the different loading environments.
Fig. 4 is a wireless tilt sensor construction synoptic diagram of the present utility model.
Embodiment
Be described in detail specific embodiment of the utility model below in conjunction with technical scheme and accompanying drawing.
Wireless tilt sensor construction of the present utility model as shown in Figure 4.The measurement of dip angle unit selects for use the sensor chip based on the MEMS technology to come induced signal, the inclination angle collecting unit is responsible for the inclination data of MEMS chip induction is sent to radio receiving transmitting module with the serial ports pattern, radio receiving transmitting module adopts the wireless universal module that has serial ports to realize, energy module adopts the general lithium battery in market, Ni-MH battery or solar cell to realize.Two wireless tilt sensor nodes are pre-loaded embedded program, the algorithm routine of amount of deflection is calculated at the above-mentioned inclination angle of operation on the computing machine.
Calculating the amount of deflection algorithm implements as follows:
P is an external load, and q is the load intensity, and l is the beam total length, and EI is a constant, the bendind rigidity of expression beam, and E is the tension and compression elastic modulus, I is a moment of inertia, order By superposition principle, the sag curve that bridge deadweight and external load produce is a formula 7,8:
y = - px 12 EI ( 3 l 2 4 - x 2 ) - qx 24 EI ( l 3 - 2 l x 2 + x 3 ) 0 ≤ x ≤ l 2 - - - ( 7 )
y = - p 12 EI ( x 3 + 9 l 2 x 4 - 3 l x 2 - l 3 4 ) - qx 24 EI ( l 3 - 2 l x 2 + x 3 ) l 2 ≤ x ≤ l - - - ( 8 )
Maximal value is got at the place at span centre:
y max = - l 3 48 EI ( p + 5 ql 8 ) - - - ( 9 )
Formula 7,8 is carried out differentiate gets the inclination angle equation:
y ' = ( 3 x 2 - 3 l 2 4 ) a + ( 6 l x 2 - l 3 - 4 x 3 ) b 0 ≤ x ≤ l 2 - - - ( 10 )
y ' = ( - 3 x 2 - 9 l 2 4 + 6 lx ) a + ( - l 3 + 6 l x 2 - 4 x 3 ) b l 2 ≤ x ≤ l - - - ( 11 )
Both sides are laid the wireless tilt sensor node respectively in spanning, record 2 inclination angle value.Substitution (10) or (11) formula, i.e. the equations of rotating angle of span centre both sides, the value that obtains unknown quantity a, b is substitution formula (7), (8) again, thereby obtain the deflection equation of both sides in the spanning.Can utilize least square method from this method, expand to multimetering.For system of the present utility model and algorithm, be to have carried out experiment test on the simple span bridge beam model of 1.44m in length, the wireless tilt sensor is put on the bridge model and powers on then, monitor channel, the computing machine that links to each other with wireless data unit constitutes network.Wireless tilt sensor acquisition data send to computing machine by serial ports with the data that receive by wireless data unit, and computer program reads serial data, after the data processing, show sag curve.Under beam self evenly load effect situation, deflection of bridge span is measured, load 1kg, 2kg, 3kg counterweight in the span centre position of beam, record corresponding deflection of bridge span with the two-point method that proposes respectively.Sag curve under the different loading environments as shown in Figure 3.Use laser displacement gauge to record corresponding amount of deflection simultaneously, the amount of deflection that records with two-point method compares, and is as shown in table 1.A is a two-point method, and B is the laser displacement gauge method.The corresponding amount of deflection that laser displacement gauge is recorded is as approximate true value.
Contrast of table 1 deflection metrology and analysis
A is the wireless tilt method, and B is the laser displacement gauge method.
As can be seen from the above experimental data, the amount of deflection of using the wireless tilt sensor to record has degree of accuracy preferably.In unloaded and loading experiment, the relative error that records amount of deflection is all less than 3%.Can verify deflection metrology system and the algorithm validity that the utility model proposes.

Claims (2)

1. deflection of bridge structure measuring system based on wireless tilt, it is characterized in that, should comprise two wireless tilt sensor units, wireless data unit and computer unit based on deflection of bridge structure measuring system of wireless tilt, computer unit adopts serial mode to be connected with wireless data unit, and carries out radio communication with the wireless tilt sensor unit; Wherein the wireless tilt sensor unit comprises general inclination angle MEMS chip, inclination angle collecting unit, wireless transmit/receive units and energy module; Wireless data unit adopts the wireless universal module that has serial ports; Computer unit comprises Calculation of Deflection unit and data display unit.
2. the deflection of bridge structure measuring system based on wireless tilt according to claim 1 is characterized in that: energy module adopts lithium battery, Ni-MH battery or solar cell.
CN2010202724109U 2010-07-27 2010-07-27 Wireless inclination based bridge structure deflection measurement system CN201731984U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN2010202724109U CN201731984U (en) 2010-07-27 2010-07-27 Wireless inclination based bridge structure deflection measurement system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN2010202724109U CN201731984U (en) 2010-07-27 2010-07-27 Wireless inclination based bridge structure deflection measurement system

Publications (1)

Publication Number Publication Date
CN201731984U true CN201731984U (en) 2011-02-02

Family

ID=43523142

Family Applications (1)

Application Number Title Priority Date Filing Date
CN2010202724109U CN201731984U (en) 2010-07-27 2010-07-27 Wireless inclination based bridge structure deflection measurement system

Country Status (1)

Country Link
CN (1) CN201731984U (en)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101915650A (en) * 2010-07-27 2010-12-15 大连理工大学 System and method for measuring deflection of bridge structure based on wireless tilt
CN103439070A (en) * 2013-08-01 2013-12-11 广州大学 Separation method for long-term deflection effect of bridge
CN105258884A (en) * 2015-10-08 2016-01-20 南京邮电大学 Bridge alignment real-time monitoring system based on high-precision inclination angle sensors
CN106248044A (en) * 2016-07-14 2016-12-21 苏交科集团股份有限公司 A kind of bridge full-bridge Multi-point deflection real-time acquisition and display system
CN107991041A (en) * 2017-11-24 2018-05-04 绍兴文理学院 Elasticity modulus test method based on virtual pure bending material
CN108008011A (en) * 2017-11-24 2018-05-08 绍兴文理学院 A kind of method of test material tensile modulus of elasticity
CN111189427A (en) * 2020-02-13 2020-05-22 桂林理工大学 Real-time monitoring method for bending deformation of simply supported beam

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101915650A (en) * 2010-07-27 2010-12-15 大连理工大学 System and method for measuring deflection of bridge structure based on wireless tilt
CN103439070A (en) * 2013-08-01 2013-12-11 广州大学 Separation method for long-term deflection effect of bridge
CN103439070B (en) * 2013-08-01 2016-07-27 广州大学 A kind of separation method of bridge Long-term Deflection effect
CN105258884A (en) * 2015-10-08 2016-01-20 南京邮电大学 Bridge alignment real-time monitoring system based on high-precision inclination angle sensors
CN106248044A (en) * 2016-07-14 2016-12-21 苏交科集团股份有限公司 A kind of bridge full-bridge Multi-point deflection real-time acquisition and display system
CN106248044B (en) * 2016-07-14 2019-03-15 苏交科集团股份有限公司 A kind of bridge full-bridge Multi-point deflection real-time acquisition and display system
CN107991041A (en) * 2017-11-24 2018-05-04 绍兴文理学院 Elasticity modulus test method based on virtual pure bending material
CN108008011A (en) * 2017-11-24 2018-05-08 绍兴文理学院 A kind of method of test material tensile modulus of elasticity
CN107991041B (en) * 2017-11-24 2019-07-23 绍兴文理学院 Elasticity modulus test method based on virtual pure bending material
CN108008011B (en) * 2017-11-24 2019-10-25 绍兴文理学院 A kind of method of test material tensile modulus of elasticity
CN111189427A (en) * 2020-02-13 2020-05-22 桂林理工大学 Real-time monitoring method for bending deformation of simply supported beam

Similar Documents

Publication Publication Date Title
CN103674114B (en) A kind of green building comprehensive detection device based on Zigbee
CN102818913B (en) Detection device and detection method for hummotion information
CN102636140B (en) Telescopic parallel pull rod type device used for measuring spatial six-degree-of-freedom motion
CN101221104B (en) Structure health monitoring method based on distributed strain dynamic test
CN104794933B (en) A kind of method for improving accuracy of geomagnetic parking stall detector
CN103048102B (en) A kind of state evaluating method of beam bridge
CN103616157B (en) The quiet calibration system of wind-tunnel balance body axle system and method
CN102721479B (en) Online monitoring method for temperature rise of outdoor electrical device
CN103598888B (en) Wearable human body motion state data monitoring system and method
CN104239736A (en) Structure damage diagnosis method based on power spectrum and intelligent algorithms
Spencer Jr et al. Next generation wireless smart sensors toward sustainable civil infrastructure
CN101504324B (en) Intelligent distinguishing method and system for inhaul cable operation state
CN104092308B (en) The electric power pylon on-line monitoring system and method that a kind of stress is measured
CN105842558B (en) A kind of charging pile performance testing device
CN102874665B (en) Method and device for accurately and quickly measuring escalator stopping distance
CN202115547U (en) Track geometry status measuring cart and measuring apparatus
CN104537724A (en) Patrol completion degree evaluation and calculation method
CN201465278U (en) Remote wireless monitoring system
CN103335589B (en) The scaling method of welded rail temperature stress sensing node
CN102159920A (en) Methods for processing measurements from accelerometer
KR100669070B1 (en) Wireless telemetry system for monitoring structure
CN101446517A (en) Method for testing vibration of high-tower structure of transmission line
CN105783694A (en) Tree diameter at breast height automatic measurer
CN104182614A (en) System and method for monitoring attitude of mechanical arm with six degrees of freedom
CN102095574B (en) Joint surface dynamic characteristic parameter testing device of rolling guide rail and testing method thereof

Legal Events

Date Code Title Description
C14 Grant of patent or utility model
GR01 Patent grant
C17 Cessation of patent right
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20110202

Termination date: 20130727