A kind of bridge deflection test method and its system based on inclinator
Technical field
The present invention relates to a kind of test method of deflection of bridge span, the amount of deflection suitable for any spanning length any position is surveyed
Examination, belongs to Bridge Inspection field, concretely relates to one of bridge machinery process high-precision and efficient bridge
Beam deflection test method.
Background technique
In Bridge Detection Experiment, deflection of bridge span need to be measured, the accuracy direct relation bridge of deflection metrology data
The evaluation of beam-like state, meanwhile, the timeliness of bridge machinery requires high.Therefore, during bridge machinery, high-precision and high efficiency
Deflection of bridge span test macro seem most important.In the prior art, the on-the-spot test of deflection of bridge span is generally with the following method:
1, deflection of bridge span is measured using optical gauges such as levels, although easy to operate, measurement accuracy is low, and measurement result is by people
It is larger to influence interference, the test of bridge dynamic deflection can not be suitable for, error is larger.2, using dial gauge, amesdial equipotential
Measurement examination deflection of bridge span is moved, scaffold need to be set up below beam body, to install deflection test instrument on scaffold, but in bridge
Under when setting up scaffold, there are complex procedures, time-consuming and laborious, and higher scaffold is there are biggish security risk,
The shaking of body and bottom differential settlement also will affect the test result of deflection of bridge span.3, with photoelectric image principle, by adopting
The picture signal of collection obtains the deflection value of bridge using data processing method, such as application No. is 200710103777.0, openly
Number for CN101055218, entitled " monitoring device and monitoring method of deflection of bridge span and displacement " Chinese invention patent application,
Its working principle is complicated, and image data acquiring is limited by specified conditions such as weather, light, data processing complex, and cost
Higher, precision is lower, practical poor operability.4, it is based on connecting pipe principle, according to the variation of the liquid level in open communicating pipe
Directly measure deflection of bridge span, the method principle is simple, but due between liquid and tube wall viscosity resistance and water and tube wall between
Capillarity, cause measuring accuracy not high, and can not be suitable for bridge dynamic deflection test.5, it is based on connecting pipe principle,
It directly converts amount of deflection to the pressure of liquid in pipe, pressure change is changed into the change of amount of deflection, such as patent using pressure transmitter
Number for 200310108447.2, Authorization Notice No. CN100385201C, entitled " Large Span Bridges deflection monitoring method "
Chinese invention patent has feasibility on theoretical method, but especially bridge span is larger or measuring point in actual mechanical process
When more, viscosity resistance is generated due to the relative flow between liquid in pipe and tube wall, the pressure of liquid has to a certain degree
Loss, lead to low measurement accuracy, while the test of bridge dynamic deflection can not be suitable for.
Therefore, there are following defects for existing highway bridge deflection test device:1, measuring accuracy is low, and error is larger;2, test dress
It is complicated to set installation, data acquire more complex, high labor cost, and working efficiency is low;3, can not be suitable for bridge dynamic deflection and across
The more detection of the deflection of bridge span such as great river and Grand Canyon.
Summary of the invention
The purpose of the present invention is to provide a kind of bridge deflection test method and its system based on inclinator, it is existing to solve
There is technology Bridge deflection test precision low, error is big, and test device installation is complicated, the low problem of data acquisition efficiency.
In order to achieve the above object, the invention proposes a kind of bridge deflection test methods based on inclinator, including:
Inclination angle measuring process:By the way that inclinator is arranged in multiple sectional positions of test bridge, the section for carrying out bridge turns
The measurement at angle obtains the corner numerical value of the inclinator;
Deflection test step:Described inclined in the collected corner numerical value of synchronization with each based on each inclinator
The difference of the initial corner value of angle instrument obtains the combination coefficient of a n first order mode, and is calculated based on the combination coefficient and obtain bridge
Amount of deflection.
The above-mentioned bridge deflection test method based on inclinator, the multiple sectional position are:Beam-ends, 1/4 across, span centre and
3/4 across.
The above-mentioned bridge deflection test method based on inclinator, the deflection of bridge span are calculate by the following formula acquisition:
Wherein, AiFor the combination coefficient,For the i-th first order mode.
The above-mentioned bridge deflection test method based on inclinator, the combination coefficient AiIt is calculate by the following formula acquisition:
Wherein, the PiAnd MiRespectively the i-th first order mode power and vibration shape quality, the ωiFor bridge structure the i-th rank from
Vibration frequency;
The PiCalculation formula be:
The MiCalculation formula be:
Wherein, the p (x) is evenly load, and the m (x) is modal mass,For the i-th first order mode.
The above-mentioned bridge deflection test method based on inclinator, i-th first order modeCan be by trigonometric series:
Wherein, the bnFor constant coefficient, L is bridge span, and variable n is the maximum order of the i-th first order mode.
The above-mentioned bridge deflection test method based on inclinator is based on the combination coefficient AiWith i-th first order modeCalculation formula away from amount of deflection described in the bridge at beam-ends x is:
The ciCalculation formula be:Wherein, the θi(i=1,2,3 ...
It 5) is the difference of the inclination value and initial reading surveyed by the inclinator.
The deflection of bridge span test macro based on inclinator that the present invention also provides a kind of, using such as described bridge based on inclinator
Beam deflection test method, including:
Inclination angle measurement module:By the way that inclinator is arranged in multiple sectional positions of test bridge, the section for carrying out bridge turns
The measurement at angle obtains the corner numerical value of the inclinator;
Deflection test module:Described inclined in the collected corner numerical value of synchronization with each based on each inclinator
The difference of the initial corner value of angle instrument obtains the combination coefficient of a n first order mode, and is calculated based on the combination coefficient and obtain bridge
Amount of deflection.
The above-mentioned deflection of bridge span test macro based on inclinator, the multiple sectional position is:Beam-ends, 1/4 across, span centre and
3/4 across.
The above-mentioned deflection of bridge span test macro based on inclinator, the deflection of bridge span are calculate by the following formula acquisition:
Wherein, AiFor the combination coefficient,For the i-th first order mode.
The above-mentioned deflection of bridge span test macro based on inclinator, the combination coefficient AiIt is calculate by the following formula acquisition:
Wherein, the PiAnd MiRespectively the i-th first order mode power and vibration shape quality, the ωiFor bridge structure the i-th rank from
Vibration frequency;
The PiCalculation formula be:
The MiCalculation formula be:
Wherein, the p (x) is evenly load, and the m (x) is modal mass,For the i-th first order mode.
The above-mentioned deflection of bridge span test macro based on inclinator, i-th first order modeCan be by trigonometric series:
Wherein, the bnFor constant coefficient, L is bridge span, and variable n is the maximum order of the i-th first order mode.
The above-mentioned deflection of bridge span test macro based on inclinator is based on the combination coefficient AiWith i-th first order modeCalculation formula away from amount of deflection described in the bridge at beam-ends x is:
The ciCalculation formula be:Wherein, the θi(i=1,2,
3 ... 5) it is the difference of the inclination value and initial reading by the inclinator surveyed.
Method in compared with the prior art, the main beneficial effect of the present invention are:
1, working principle is simple, and theoretical basis is reliable, is not influenced by bridge structure form and bridge changes of section, is applicable in
In the deflection test of any span bridge's any position.
2, easy to use, test macro each section forms in-site installation conveniently, and test job is high-efficient, measuring accuracy
Height, data acquisition are convenient.
3, test macro is not limited by span and field working conditions, can be suitable for crossing over the bridges such as great river and Grand Canyon
The test of beam deflection.
Detailed description of the invention
Fig. 1 is that the present invention is based on the bridge deflection test method step schematic diagrams of inclinator;
Fig. 2 is that the present invention is based on the deflection of bridge span test system structure block diagrams of inclinator;
Fig. 3 is that the present invention is based on the deflection of bridge span test macro application schematic diagrams of inclinator.
Wherein, appended drawing reference:
1 inclination angle measurement module, 2 deflection test module
S1~S2:The administration step of various embodiments of the present invention
Specific embodiment
Below in conjunction with the drawings and specific embodiments, the present invention will be described in detail, but not as a limitation of the invention.
The present invention provides a kind of bridge deflection test method based on corner, is bridge by the corner change transitions in bridge section
The variation of beam deflection, i.e., in 5 sections of bridge, arrangement inclinator measures sectional twisting angle, and (electricity) signal of change of pitch angle passes through letter
Number cable is sent to acquisition system in time, and the mathematical relationship formula of deflection of bridge span and corner is extrapolated using section inclination value, into
And extrapolate the amount of deflection at any position.Easily operated and test data of the invention is accurate, and measurement efficiency is high, and performance stabilization can
It leans on, is not influenced by bridge structure form and bridge changes of section, can solve and tested across the deflection of bridge span such as great river and Grand Canyon
Difficult, the problems such as measure data precision is poor.
The side that the method for the present invention is made of by solving synchronization the difference of different location inclinator reading and initial reading
Journey group obtains the combination coefficient of 4 first order modes, then calculates deflection of bridge span equation, the final amount of deflection for determining spanning any position
Value.
In order to eliminate the influence of bridge structure form and bridge changes of section, using the bridge vibration shape side in Structural Dynamics
Journey is simplified and is changed using bridge sectional twisting angle to solve the formula of deflection equation.
As shown in Figure 1, a kind of bridge deflection test method based on inclinator provided by the invention, including:
Inclination angle measuring process S1:By the way that inclinator is arranged in multiple sectional positions of test bridge, the section of bridge is carried out
The measurement of corner obtains the corner numerical value of inclinator;Deflection test step S2:It is collected based on each inclinator in synchronization
Corner numerical value and each inclinator initial corner value difference obtain a n first order mode combination coefficient, and be based on combination system
Number, which calculates, obtains deflection of bridge span.
With reference to the accompanying drawings and detailed description, the specific embodiment of the invention is described in further detail:
The range of inclinator sensor is -3.00 × 10 in specific embodiment4Rad~3.00 × 104Rad, the survey of inclinator
It tries precision and chooses 106Rad can meet actual test requirement, and corresponding displacement measurement precision is 0.01mm.
In inclinator bridge deflection test method, in test bridge beam end, 1/4 across, span centre and 3/4 across sectional position installation
Inclinator, and it is connected to deflection of bridge span test macro.
In inclinator bridge deflection test method, test bridge sectional twisting angle change transitions are the mechanism of deflection of bridge span variation
For:For beam-ends, 1/4 across, span centre and 3/4 across inclinator initial reading, u (x) is to scratch away from the bridge at beam-ends x
Degree,Be after bridge is acted on by external load deflection deformation occurs, beam-ends, 1/4 across, span centre and 3/4 across inclination angle
Instrument reading.When by external load deflection deformation is occurred for bridge, obtain:
In above formula, θi(i=1,2,3 ... 5) be deformation front and back beam-ends, 1/4 across, span centre and 3/4 across inclinator reading
Difference.
By Structural Dynamics it is found that under evenly load p (x) effect, bridge deflection curve is represented by the folded of the multistage vibration shape
Add, i.e.,:
In above formula,And AiRespectively the i-th first order mode and a combination thereof coefficient.AiIt is represented by:
In above formula, L is bridge span, and m (x) is modal mass, ωiFor the i-th rank natural frequency of vibration of structure;PiAnd MiRespectively
For the i-th first order mode power and vibration shape quality.
The trigonometrical number form that the natural mode of vibration of beam body can be written as follow:
In above formula, bnFor constant coefficient, L is bridge span, and variable n is the maximum order of the i-th first order mode.
It will be in formula (6)Substitution formula can obtain in (4):
Within the unit time, the expression formula of p (x) be it is fixed, do not change at any time with the position of active force, therefore,
Formula (7) can be reduced to:
In above formula,For the concentrated force equivalence value for acting on beam body in the unit time, L is bridge span.
Each rank circular frequency ω of bridge structureiGenerally constant, will be in formula (6)Substitution formula can obtain in (5):
Modal mass is simplified, therefore, formula (9) can be reduced to:
In above formula,For beam body linear mass.
By formula (6), formula (8), formula (10) and ωiIn substitution formula (2), it can obtain:
In above formula, removeOutside for x function, remaining is constant, with ciInstead of therefore, formula (11) can be reduced to:
The inclination angle equation in beam body section can differentiate to obtain by formula (12) to x:
Specific embodiments of the present invention only consider 4 rank mode, that is, take n=4, invention is not limited thereto.According to actual measurement
The difference θ of inclination value and initial readingi(i=1,2,3 ... 4), can establish the equation group of 4 equations composition;
Solve system of equation can obtain ci(i=1,2 ... 4), by ci(i=1,2 ... 4) it substitutes into formula (12), can obtain away from beam
Hold the deflection of bridge span equation at x.
The above process shows during the test, to utilize the sectional twisting angle of deflection testing system record different moments
It is found out by solve system of equation away from the deflection of bridge span equation at beam-ends x.
The deflection test and bridge health monitoring process Bridge that this test method can be used in bridge machinery are long-term to scratch
Degree and linear monitoring and test.The present invention can also have other embodiment, all skills formed using same replacement or equivalent transformation
Art scheme, all falls within the scope of protection of present invention.
The deflection of bridge span test macro based on inclinator that the present invention also provides a kind of, using such as described bridge based on inclinator
Beam deflection test method, as shown in Fig. 2, including:
Inclination angle measurement module 10:Inclinator is set in multiple sectional positions of test bridge, carries out the sectional twisting angle of bridge
Measurement, obtain the corner numerical value of inclinator;
Deflection test module 20:Based on each inclinator in the collected corner numerical value of synchronization and each inclinator
The difference of initial corner value obtains the combination coefficient of a n first order mode, obtains deflection of bridge span based on combination coefficient.
Specific embodiment of the invention systematic difference is as shown in figure 3, include that multiple inclinators 1, connecting wire 2 and bridge are scratched
Degree test 3.Plurality of inclinator 1 is set to the beam-ends a1 of bridge, 1/4 across b, span centre c and 3/4 cross-location d, beam-ends a2, when
When deflection deformation occurs for bridge, the variation of bridge sectional twisting angle is reflected in the reading variation of inclinator 1, and is input to by conducting wire 2
In deflection of bridge span test macro 3.It is made of by solving synchronization the difference of different location inclinator reading and initial reading
Equation group obtains the combination coefficient of 4 first order modes, and then calculates deflection of bridge span equation.
In conclusion the object of the present invention is to provide a kind of tests of the deflection of bridge span of high-precision, high efficiency and strong applicability
Method and its system, the method overcome existing deflection test methods can not be suitable for across deflection of bridge span such as great river and Grand Canyons
The deficiency of detection is passed through the electric signal that inclinator acquires by arranging that inclinator measures sectional twisting angle in 5 sections of bridge
Signal cable is sent to deflection testing system in time, is closed using the mathematics that deflection of bridge span and corner are extrapolated in inclination value variation in section
It is formula, and then extrapolates the amount of deflection at different location.Not only measuring accuracy is high for this method, and strong applicability, easy to operate,
It is not influenced by bridge structure form and bridge changes of section, practical value with higher.
Certainly, the present invention can also have other various embodiments, without deviating from the spirit and substance of the present invention, ripe
It knows those skilled in the art and makes various corresponding changes and modifications, but these corresponding changes and change in accordance with the present invention
Shape all should fall within the scope of protection of the appended claims of the present invention.