CN109635497A - A kind of girder steel bridge longevity and reliability analyzing method based on nonlinear impairments theory - Google Patents
A kind of girder steel bridge longevity and reliability analyzing method based on nonlinear impairments theory Download PDFInfo
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Abstract
The present invention relates to a kind of girder steel bridge longevity and reliability analyzing method based on nonlinear impairments theory, the analysis method is the following steps are included: S1, modeling layout: carrying out modeling according to each dangerous point of truss bridge and random point and layouts, layouted frequency-distributed sample is measured, layouted sign frequency discrete sample is calculated；S2, the truss bridge structural damage factor is calculated according to sign frequency discrete sample；S3, truss bridge structural damage amount and damage safety angle value are calculated according to the truss bridge structural damage factor；S4, truss bridge dynamic load is calculated, obtains the total stress of truss bridge in a monitoring cycle；S5, truss bridge service life and reliability are calculated according to the total stress of truss bridge.
Description
Technical field
The invention belongs to safety appraisement of structure fields, relate generally to a kind of truss bridge use based on nonlinear impairments theory
Service life and reliability analyzing method.
Technical background
The fatigue damage of bridge mostlys come from the alternative cycle stress under the dynamic loadings such as vehicle and wind, and bridge knot
The fatigue damage accumulation of structure and main member reduces the degeneration for causing bridge structure and safety.Since bridge member is used
Material be not it is uniform continuous, there are in fact many small defects, with the extension of active time, in load and
Under such environmental effects, these fine defects can gradually develop, merge formation damage, and gradually form macroscopic view in the material and split
Line.On the one hand these damages affect the durability of structure, shorten bridge structure service life；On the other hand structure can be caused
The reduction of strength and stiffness has buried security risk for road operation.
Although existing minority bridge is equipped with health monitoring systems, real-time monitoring, its all kinds of prison are carried out to operation state
Measured data correlation degree is very low, it is difficult to be directly used in safe condition when evaluation bridge operation, can not effectively serve in bridge
Maintenance pipe support.And when actual operation, bridge and driving vehicle are a coupled systems, are responded by such environmental effects.
Engineering circles are mostly used mode class method to study the Bridge Structural Damage assessment based on vibration at present.But mode class method is in practice
The change for being difficult to differentiate between mode observation is as caused by structural damage or since the change of operating status or environmental factor is made
At.This is because even if configuration state is not degenerated, also due to environmental factor (noise, temperature, humidity etc.) and fortune
The change of row state makes power observed responses change.Existing Study on Structural Damage Identification based on probability also spininess to determination
Property excitation, the load forms such as white noise and environmental excitation, it is very sensitive to dynamic load parameter stochastic property, can not effectively identify damage
Wound.
Due to the bridge complexing action by the dynamic loads such as vehicle and wind and environment multimedium in actual operations, close at present
It is also seldom that the quantitative study that influences on its long term life is damaged under discontinuous luffing pulsating stress in bridge.A small amount of bridge longevity
Quantity research determined by fate is also based only on linear damage theory, and the analysis of linear damage theory loading conditions discontinuous for bridge is ground
Study carefully that there are inadequate natural endowments, therefore it is larger to the quantitative analysis error of bridge life.And conventional linear defect theory can not solve
The problem of " after load, environment change, how bridge damnification and remaining life change ".
Summary of the invention
The present invention uses the Uncertainty Method based on performance function Damage Assessment Method after improvement, joins to dynamic load
Number randomness is insensitive；Simultaneously according to the loading conditions of bridge actual complex, existing nonlinear impairments theory is corrected, to vehicle
, the bridge service life after the discontinuous variable amplitude loading such as wind, rain or incident carries out quantitative analysis, and calculates its safety and make
Use reliability.To achieve the above object, the invention provides the following technical scheme:
A kind of girder steel bridge longevity and reliability analyzing method based on nonlinear impairments theory, this method includes following step
It is rapid:
S1, modeling are layouted: modeling is carried out according to each dangerous point of truss bridge and random point and is layouted, measure layouted frequency from
Sample is dissipated, layouted sign frequency discrete sample is calculated；
S2, the truss bridge structural damage factor is calculated according to sign frequency discrete sample；
S3, truss bridge structural damage amount and damage safety angle value are calculated according to the truss bridge structural damage factor；
S4, truss bridge dynamic load is calculated, obtains the total stress of truss bridge in a monitoring cycle；
S5, truss bridge service life and reliability are calculated according to the total stress of truss bridge.
Wherein, specific step is as follows by step S1:
(1) modeling is layouted: being analyzed according to truss bridge structure and preliminary static load, is utilized finite element analysis software or reason
It by each dangerous point on truss bridge main structure and key member is calculated, then layouts, measures to each dangerous point and random point
Its structural dynamic characteristic；
(2) measure layouted frequency-distributed sample: car load is continuously to divide in time to the power excitation of truss bridge
The random load of cloth, spatially continuous moving, discrete to the progress of this random load, each Discrete Stochastic pulse duration is set as
1/t seconds；If the truss bridge is L meters long, the primary travelling gantry frame of crossing of vehicle is then separated into Lt/V random pulses load by speed limit V meter per second
Lotus；Spectrum analysis is made micro- section to each 1/t seconds time, obtains spectrogram；N frequency before being extracted to each micro- section of frequency spectrum by amplitude size
Rate value, then collected layouted frequency values have nLt/V under the primary excitation of travelling gantry frame excessively, by these frequency values IiAs one
Discrete sample of institute's cloth dot frequency；
(3) calculate layouted sign frequency discrete sample: the appearance of truss bridge structure damages its intrinsic frequency and can reduce, and frequency
Spectrum embody be structure self-vibration characteristic, structure it is not damaged or damage the geometry physical characteristic without development under remain unchanged；One
The frequency values repeatedly occurred in secondary discrete sample, i.e. frequency stabilization point, it is insensitive to environmental parameter；It will be in a discrete sample
The frequency of these instruction structure degree of impairment is weighted and averaged, and obtains sign frequency IC, have:
K in formulaiFor the repetition probability of Frequency point, n in a cycle by, to the measurement for carrying out continuous several times of layouting, obtaining
The sign frequency discrete sample layouted in one cycle, quantity are set as NCIt is a.
Wherein, the truss bridge structural damage factor is calculated according to sign frequency discrete sample in step S2, the specific steps are as follows:
According to aforementioned layouted sign frequency discrete sample, if ICiFor the sign frequency of certain spatial structure faulted condition；If
JCBy the sign frequency I in one cycle that layoutedCiAverage value, i.e.,
For consider the various media of environment uncertain condition, if QCBy the sign frequency I in one cycle that layoutedCiMark
It is quasi- poor, i.e.,
Using Gaussian function, truss bridge structural damage factor P is calculated, is hadWherein, f (x) is Gaussian function
Number, I0For the not damaged state sign frequency of structure, JCFor sign frequency average value, QCFor sign frequency standard deviation；Consider that environment is more
Medium introduces parameter lambda related with elasticity modulus of materials E and temperature T, Gaussian function is corrected to bridge beam action are as follows:
λ in formula has:
E in formula0=2.0 × 105MPa, T0=298 DEG C (absolute temperature).
Wherein, step S3 calculates truss bridge structural damage amount D according to the truss bridge structural damage factor0With damage safety degree R0
Value, the specific steps are as follows:
To truss bridge structural damage amount D0, have:
D0=2P-1
To truss bridge structural damage degree of safety R0, have:
R0=2-2P
P is the truss bridge structural damage factor in formula.
Wherein, it includes traffic load, wind load and rain load that step S4, which calculates truss bridge dynamic load,.
Wherein, the traffic load is calculated by following steps:
(1) the average traffic load F that truss bridge a cycle is subject to is calculatedcars, thenFormula
In,For average vehicle weight；For average spacing；Truss bridge is L meters long, speed limit V meter per second, and g is gravity constant, dynamic vehicle load lotus
COEFFICIENT KdCalculation formula are as follows:
In formula, pavement grade Q points are 1~8 grade by country, △ Q=Q-1；Vehicle velocity V, △ V=V-60km/h.
Wherein, the wind load is calculated by following steps:
(1) the average wind load F that truss bridge a cycle is subject to is calculatedwind, then Fwind=β μh·μs·Pwind·A；
In formula, β is the wind pulse for characterizing wind load impulse excitation；μhFor height variation coefficient of wind pressure；μsFor wind load body
Type coefficient；PwindFor fundamental wind pressure；A is front face area；
To wind pulse β, calculating formula are as follows:
Wherein, μ is the peak value value preserving factor；S is that deflection of bridge span caused by wind load changes, wherein S1Position is measured to be layouted
Move average value, S2By measurement displacement mean square deviation of being layouted；
To fundamental wind pressure Pwind, calculating formula are as follows:
Pwind=kU2
Wherein, k is constant；U is wind speed.
Wherein, the rain load is calculated by following steps:
(1) the average rain load F that truss bridge a cycle is subject to is calculatedrain, then Frain=Prain·A；In formula, rain pressure
Prain；Bridge floor area A；Prain=g ρ1H, wherein g is gravity constant, ρ1For rainwater density, unit area when h is torrential rain
Average depth of accumulated water.
Wherein, according to traffic load, wind load, rain LOAD FOR truss bridge structure total stress, calculate monitoring week
In phase, equivalent stress width σ of the truss bridge under multi-load effectEValue:
In formula, k is variable-amplitude fatigue curve coefficients；σiFor a certain period truss bridge stress amplitude；niFor corresponding σiSteel when stress amplitude
Beam bridge loaded fatigue life cycle in one cycle.
Wherein, specific step is as follows for step S5 calculating truss bridge service life and reliability:
(1) truss bridge service life NfAre as follows:
Nfi=9.384K (1.01 σ0-σi)1-A·Ri-1
(2) its use reliability of truss bridge R are as follows:
In formula, Ri-1Its structure existing damage safety degree when starting for a cycle；σiIt is acted on for multi-load in a cycle
Flowering structure stress amplitude；σ0For fatigue limit；A, K is constant；niFor corresponding σiTruss bridge is loaded in one cycle when stress amplitude
Fatigue life cycle.
Specifically, total stress when being acted on about truss bridge in one monitoring cycle of calculating by multimedium, by above-mentioned point
Obtained traffic load, wind load, rain load the input existing model of finite element software is analysed to be analyzed, by fourth strength theory,
Calculate the total stress (i.e. Fatigue Stress Amplitude) of truss bridge structure.To equivalent stress width σEHave:
In formula, k is variable-amplitude fatigue curve coefficients；σiFor a certain period component stress width；niFor corresponding σiComponent when stress amplitude
Cycle-index.
Specifically, about truss bridge service life and reliability is calculated, it is non-in receiving vehicle, wind, rain etc. according to truss bridge
The actual conditions of the complexity such as continuous amplitude transforming load etc., to the CHABOCHE nonlinear damage constitutive model dD=f of international mainstream now (D,
σ) dn is modified, and application is as follows:
(1) truss bridge service life NfAre as follows:
Nfi=9.384K (1.01 σ0-σi)1-A·Ri-1
(2) its use reliability of truss bridge R are as follows:
A, K value is material properties.After obtaining preliminary data by its fatigue test, above-mentioned formula is brought into, it is soft with Origin etc.
Part carries out Function Fitting and obtains its A, K value.
Compared with prior art, the beneficial effects of the present invention are: the present invention is fully considering various actual complex load
Discontinuous effect with surrounding medium to bridge, based on modified nonlinear damage constitutive model to normal operation or incident after
Bridge service life carries out more accurate quantitative analysis and reliability calculating；And friendship will not be interrupted and be interfered to the method for the present invention
It is logical, the time of day of non-destructive tests and durability analysis result more close to bridge structure under operation state.
Detailed description of the invention
Fig. 1 is the flow chart of present invention prediction truss bridge service life and its safety reliability；
Fig. 2 is reliability data of the truss bridge under different equivalent stress amplitude, heterogeneous expectations Years Of Service.
Specific embodiment
In the following with reference to the drawings and specific embodiments, technical solution that the present invention is furture elucidated, it should be understood that embodiment is only used for
Illustrate the present invention rather than limit the scope of the invention, after the present invention has been read, those skilled in the art are to the present invention
The modifications of various equivalent forms fall within the application range as defined in the appended claims.
A kind of girder steel bridge longevity and reliability analyzing method based on nonlinear impairments theory, this method includes following step
It is rapid:
S1, modeling are layouted: modeling is carried out according to each dangerous point of truss bridge and random point and is layouted, measure layouted frequency from
Sample is dissipated, layouted sign frequency discrete sample is calculated；
S2, the truss bridge structural damage factor is calculated according to sign frequency discrete sample；
S3, truss bridge structural damage amount and damage safety angle value are calculated according to the truss bridge structural damage factor；
S4, truss bridge dynamic load is calculated, obtains the total stress of truss bridge in a monitoring cycle；
S5, truss bridge service life and reliability are calculated according to the total stress of truss bridge.
Wherein, specific step is as follows by step S1:
(1) modeling is layouted: being analyzed according to truss bridge structure and preliminary static load, is utilized finite element analysis software or reason
It by each dangerous point on truss bridge main structure and key member is calculated, then layouts, installs to each dangerous point and random point
Monitoring device measures its structural dynamic characteristic；
(2) measure layouted frequency-distributed sample: car load is continuously to divide in time to the power excitation of truss bridge
The random load of cloth, spatially continuous moving, discrete to the progress of this random load, each Discrete Stochastic pulse duration is set as
1/t seconds；If the truss bridge is L meters long, the primary travelling gantry frame of crossing of vehicle is then separated into Lt/V random pulses load by speed limit V meter per second
Lotus；Spectrum analysis is made micro- section to each 1/t seconds time, obtains spectrogram；N frequency before being extracted to each micro- section of frequency spectrum by amplitude size
Rate value, then collected layouted frequency values have nLt/V under the primary excitation of travelling gantry frame excessively, by these frequency values IiAs one
Discrete sample of institute's cloth dot frequency；
(3) calculate layouted sign frequency discrete sample: the appearance of truss bridge structure damages its intrinsic frequency and can reduce, and frequency
Spectrum embody be structure self-vibration characteristic, structure it is not damaged or damage the geometry physical characteristic without development under remain unchanged；One
The frequency values repeatedly occurred in secondary discrete sample, i.e. frequency stabilization point, it is insensitive to environmental parameter；It will be in a discrete sample
The frequency of these instruction structure degree of impairment is weighted and averaged, and obtains sign frequency IC, have:
K in formulaiFor the repetition probability of Frequency point, n in a cycle by, to the measurement for carrying out continuous several times of layouting, obtaining
The sign frequency discrete sample layouted in one cycle, quantity are set as NCIt is a.
Wherein, the truss bridge structural damage factor is calculated according to sign frequency discrete sample in step S2, the specific steps are as follows:
According to aforementioned layouted sign frequency discrete sample, if ICiFor the sign frequency of certain spatial structure faulted condition；If
JCBy the sign frequency I in one cycle that layoutedCiAverage value, i.e.,
For consider the various media of environment uncertain condition, if QCBy the sign frequency I in one cycle that layoutedCiMark
It is quasi- poor, i.e.,
Using Gaussian function, truss bridge structural damage factor P is calculated, is hadWherein, f (x) is Gaussian function
Number, I0For the not damaged state sign frequency of structure, JCFor sign frequency average value, QCFor sign frequency standard deviation；Consider that environment is more
Medium introduces parameter lambda related with elasticity modulus of materials E and temperature T, Gaussian function is corrected to bridge beam action are as follows:
λ in formula has:
E in formula0=2.0 × 105MPa, T0=298 DEG C (absolute temperature).
Wherein, step S3 calculates truss bridge structural damage amount D according to the truss bridge structural damage factor0With damage safety degree R0
Value, the specific steps are as follows:
To truss bridge structural damage amount D0, have:
D0=2P-1
To truss bridge structural damage degree of safety R0, have:
R0=2-2P
P is the truss bridge structural damage factor in formula.
Wherein, it includes traffic load, wind load and rain load that step S4, which calculates truss bridge dynamic load,.
Wherein, the traffic load is calculated by following steps:
(1) the average traffic load F that truss bridge a cycle is subject to is calculatedcars, thenFormula
In,For average vehicle weight；For average spacing；Truss bridge is L meters long, speed limit V meter per second, and g is gravity constant, dynamic vehicle load lotus
COEFFICIENT KdCalculation formula are as follows:
In formula, pavement grade Q points are 1~8 grade by country, △ Q=Q-1；Vehicle velocity V, △ V=V-60km/h.
Wherein, the wind load is calculated by following steps:
(1) the average wind load F that truss bridge a cycle is subject to is calculatedwind, then Fwind=β μh·μs·Pwind·A；
In formula, β is the wind pulse for characterizing wind load impulse excitation；μhFor height variation coefficient of wind pressure；μsFor wind load body
Type coefficient；PwindFor fundamental wind pressure；A is front face area；
To wind pulse β, calculating formula are as follows:
Wherein, μ is the peak value value preserving factor；S is that deflection of bridge span caused by wind load changes, wherein S1Position is measured to be layouted
Move average value, S2By measurement displacement mean square deviation of being layouted；
To fundamental wind pressure Pwind, calculating formula are as follows:
Pwind=kU2
Wherein, k is constant；U is wind speed.
Wherein, the rain load is calculated by following steps:
(1) the average rain load F that truss bridge a cycle is subject to is calculatedrain, then Frain=Prain·A；In formula, rain pressure
Prain；Bridge floor area A；Prain=g ρ1H, wherein g is gravity constant, ρ1For rainwater density, unit area when h is torrential rain
Average depth of accumulated water.
Wherein, according to traffic load, wind load, rain LOAD FOR truss bridge structure total stress, calculate monitoring week
In phase, equivalent stress width σ of the truss bridge under multi-load effectEValue:
In formula, k is variable-amplitude fatigue curve coefficients；σiFor a certain period truss bridge stress amplitude；niFor corresponding σiSteel when stress amplitude
Beam bridge loaded fatigue life cycle in one cycle.
Wherein, specific step is as follows for step S5 calculating truss bridge service life and reliability:
(1) truss bridge service life NfAre as follows:
Nfi=9.384K (1.01 σ0-σi)1-A·Ri-1
(2) its use reliability of truss bridge R are as follows:
In formula, Ri-1Its structure existing damage safety degree when starting for a cycle；σiIt is acted on for multi-load in a cycle
Flowering structure stress amplitude；σ0For fatigue limit；A, K is constant；niFor corresponding σiTruss bridge is loaded in one cycle when stress amplitude
Fatigue life cycle.
In order to illustrate technical effect of the invention, the present invention is analysis object with Xiamen Haicang bridge.Xiamen Haicang bridge
It is the full floating steel box beam suspension bridge of three stride continuous of a two-way six-lane, has both Urban Bridge function, it is about 6000 meters of overall length, eastern
Channel Bridge is that the main bridge of suspension cable is 1108 meters long, and 648 meters of main span, 36.6 meters of bridge deck width, design capacity is 50000/day, row
Vehicle speed per hour is 80 km/h, is broken ground within 1997, completion in 1999 is open to traffic.Steel box-girder material is Q345 steel, and steel box-girder is net with sea
It is 55 meters high.Bridge has 140 meters of high double towers, and two main push-towing ropes of restocking hold main push-towing rope and steel box-girder by sunpender.Locating regional climate
Mildly, abundant rainfall, about 3.4 meter per second of average of the whole year wind speed are subtropical zone monsoon marine climate.October pair in May, 2017-
Marine gastropod has carried out segmentation Centralizing inspection, 24 × 7 hours every time, detects six periods.
As shown in Figure 1, a kind of girder steel bridge longevity and reliability analyzing method based on nonlinear impairments theory of the invention
Main includes following several steps:
Modeling is carried out according to the finite element preliminary analysis of marine gastropod structure and load to layout to monitor and obtain truss bridge institute
It layouts sign frequency discrete sample.The layouted sign frequency discrete sample of truss bridge is calculated, its structural damage factor P value is obtained
(0.50139)。
Truss bridge structural damage amount D is calculated by formula0It is worth (0.278%) and structural damage degree of safety R0It is worth (99.722%).
Calculate traffic load.It is obtained by the monitoring magnitude of traffic flow in the peak period period in each period, by truss bridge institute
There is the average spacing S of automobile, taking multiple averaging to obtain S is 58.374 meters；It obtains owning in each period by truss bridge by detection
Automotive average weight m is 4.217 tons.Relevant parameter is substituted into vehicle dynamics loading coefficient Kd formula, such as following formula:
Kd=(1.026+0.236 × 1) × (1.022+0.0076 × 20) × [1+0.52exp (- 4.217/5.47)]
K is calculateddValue is 1.838.Above-mentioned parameter is substituted into traffic load formula,?
Average traffic load of the truss bridge in the peak period period is 1442kN.
Calculate wind load.It is layouted by displacement monitoring sensor measure and calculation and measures moving average S1, it is displaced mean square deviation
S2, taking wind shake value preserving factor mu is 2.08.Formula is substituted into, calculating its wind pulse β is 1.741.By wind speed wind direction sensor in wind
The data of biggish some cycle monitoring in October of speed, mean wind speed U are 6.796 meter per seconds, and relevant parameter is substituted into formula, is had:
Pwind=0.613 × 6.7962
Fwind=1.741 × 1.22 × 1.08 × 28.312 × 16195；
By calculating to obtain truss bridge wind load FwindFor 1051.8kN.
Calculate rain load.When being rained by instrument monitoring, bridge unit area is averaged depth of accumulated water h as 2.73mm, and rainwater is close
Degree is set as 1kg/m3, calculates bridge when raining and is averaged rain load are as follows:
Frain=g ρ hA=9.8N/kg × 1kg/m3×0.00273m×40553m2
It calculates, obtains rain load FrainFor 1.085kN.Therefore to smoothly bridge is drained, rain loading effect is little, can not
It is included in total stress.
According to fourth strength theory, the traffic load of above-mentioned analysis, wind load, rain load are inputted into finite element analysis software
It is calculated in existing model, obtaining its Fatigue Stress Amplitude (i.e. total stress) σ is 54.203MPa.By all 6 period monitorings
Data, calculate its 5-10 month equivalent stress width σEFor 37.525MPa.
Fatigue and cyclic cycle is calculated with the vehicle number passed through；If because the bad weathers such as storm lead to no vehicle when driving, with
Self excited vibrational frequency of bridge span calculates its fatigue and cyclic cycle.Being calculated the truss bridge natural frequency of vibration average value is 2.13HZ.
It calculates truss bridge both haveing damage, under a variety of Dynamic Loadings and futuristic design Years Of Service, use safely
Reliability R, calculation method are as follows:
In formula, σiFor bridge component mean stress width in one cycle；niFor truss bridge loaded circulation in one cycle
Number；R0For initial damage degree of safety (99.722%).
Calculate truss bridge both have damage and a variety of Dynamic Loadings under service life Nf, calculation method are as follows:
Nfi=682.13 (58.58 × 106-σi)0.9698·Ri-1
Referring to fig. 2, the reliable degree Fig. 2 shows truss bridge under different equivalent stress amplitude, heterogeneous expectations Years Of Service
According to, under initial damage and average annual vehicle flowrate unanimous circumstances, different equivalent stress amplitude under heterogeneous expectations Years Of Service can
Also different by degree data variation, under identical expected Years Of Service, equivalent stress width is bigger, and the speed of reliability decline is got over
Fastly, under identical equivalent stress width, with the increase of expected Years Of Service, reliability is in non-linear decline.
The above description is only an embodiment of the present invention, is not intended to limit the scope of the invention, all to utilize this hair
Equivalent structure or equivalent flow shift made by bright description is applied directly or indirectly in other relevant technology necks
Domain is included within the scope of the present invention.
Claims (10)
1. a kind of girder steel bridge longevity and reliability analyzing method based on nonlinear impairments theory, it is characterised in that: this method packet
Include following steps:
S1, modeling are layouted: being carried out modeling according to each dangerous point of truss bridge and random point and are layouted, measure layouted frequency-distributed sample
This, calculates layouted sign frequency discrete sample；
S2, the truss bridge structural damage factor is calculated according to sign frequency discrete sample；
S3, truss bridge structural damage amount and damage safety angle value are calculated according to the truss bridge structural damage factor；
S4, truss bridge dynamic load is calculated, obtains the total stress of truss bridge in a monitoring cycle；
S5, truss bridge service life and reliability are calculated according to the total stress of truss bridge.
2. a kind of girder steel bridge longevity and reliability analyzing method based on nonlinear impairments theory as described in claim 1,
Be characterized in that: specific step is as follows by step S1:
(1) modeling is layouted: being analyzed according to truss bridge structure and preliminary static load, is utilized finite element analysis software or theoretical meter
Each dangerous point on truss bridge main structure and key member is calculated, then layouts to each dangerous point and random point, measures its knot
Structure dynamic characteristics；
(2) measure layouted frequency-distributed sample: car load is continuously distributed in time, empty to the power excitation of truss bridge
Between upper continuous moving random load, this random load is carried out discrete, each Discrete Stochastic pulse duration is set as 1/t
Second；If the truss bridge is L meters long, the primary travelling gantry frame of crossing of vehicle is then separated into Lt/V random pulses load by speed limit V meter per second；It is right
Micro- of each 1/t seconds time makees spectrum analysis, obtains spectrogram；N frequency values before being extracted to each micro- section of frequency spectrum by amplitude size,
Then collected layouted frequency values have nLt/V under the primary excitation of travelling gantry frame excessively, by these frequency values IiAs institute's cloth
Discrete sample of dot frequency；
(3) calculate layouted sign frequency discrete sample: the appearance of truss bridge structure damages its intrinsic frequency and can reduce, and frequency spectrum body
Existing is structure self-vibration characteristic, structure it is not damaged or damage the geometry physical characteristic without development under remain unchanged；Once from
The frequency values repeatedly occurred in sample, i.e. frequency stabilization point are dissipated, it is insensitive to environmental parameter；By these in a discrete sample
The frequency of instruction structure degree of impairment is weighted and averaged, and obtains sign frequency IC, have:
K in formulaiFor the repetition probability of Frequency point, n is by, to the measurement for carrying out continuous several times of layouting, obtaining institute's cloth in a cycle
The sign frequency discrete sample of point in one cycle, quantity are set as NCIt is a.
3. a kind of girder steel bridge longevity and reliability analyzing method based on nonlinear impairments theory as claimed in claim 2,
It is characterized in that: the truss bridge structural damage factor being calculated according to sign frequency discrete sample in step S2, the specific steps are as follows:
According to layouted sign frequency discrete sample, if ICiFor the sign frequency of certain spatial structure faulted condition；If JCFor institute's cloth
Put sign frequency I in one cycleCiAverage value, i.e.,
For consider the various media of environment uncertain condition, if QCBy the sign frequency I in one cycle that layoutedCiStandard
Difference, i.e.,
Using Gaussian function, truss bridge structural damage factor P is calculated, is hadWherein, f (x) is Gaussian function, I0
For the not damaged state sign frequency of structure, JCFor sign frequency average value, QCFor sign frequency standard deviation；Consider environment multimedium
To bridge beam action, parameter lambda related with elasticity modulus of materials E and temperature T is introduced, Gaussian function is corrected are as follows:
λ in formula has:
E in formula0=2.0 × 105MPa, T0=298 DEG C (absolute temperature).
4. a kind of girder steel bridge longevity and reliability analyzing method based on nonlinear impairments theory as claimed in claim 3,
Be characterized in that: step S3 calculates truss bridge structural damage amount D according to the truss bridge structural damage factor0With damage safety degree R0Value, tool
Steps are as follows for body:
To truss bridge structural damage amount D0, have:
D0=2P-1
To truss bridge structural damage degree of safety R0, have:
R0=2-2P
P is the truss bridge structural damage factor in formula.
5. a kind of girder steel bridge longevity and reliability analyzing method based on nonlinear impairments theory as claimed in claim 4,
Be characterized in that: it includes traffic load, wind load and rain load that step S4, which calculates truss bridge dynamic load,.
6. a kind of girder steel bridge longevity and reliability analyzing method based on nonlinear impairments theory as claimed in claim 5,
Be characterized in that: the traffic load is calculated by following steps:
(1) the average traffic load F that truss bridge a cycle is subject to is calculatedcars, thenIn formula,
For average vehicle weight；For average spacing；Truss bridge is L meters long, speed limit V meter per second, and g is gravity constant, dynamic vehicle load lotus coefficient
KdCalculation formula are as follows:
In formula, pavement grade Q points are 1~8 grade by country, △ Q=Q-1；Vehicle velocity V, △ V=V-60km/h.
7. a kind of girder steel bridge longevity and reliability analyzing method based on nonlinear impairments theory as claimed in claim 6,
Be characterized in that: the wind load is calculated by following steps:
(1) the average wind load F that truss bridge a cycle is subject to is calculatedwind, then Fwind=β μh·μs·Pwind·A；
In formula, β is the wind pulse for characterizing wind load impulse excitation；μhFor height variation coefficient of wind pressure；μsFor wind load figure system
Number；PwindFor fundamental wind pressure；A is front face area；
To wind pulse β, calculating formula are as follows:
Wherein, μ is the peak value value preserving factor；S is that deflection of bridge span caused by wind load changes, wherein S1To be layouted, measurement displacement is flat
Mean value, S2By measurement displacement mean square deviation of being layouted；
To fundamental wind pressure Pwind, calculating formula are as follows:
Pwind=kU2
Wherein, k is constant；U is wind speed.
8. a kind of girder steel bridge longevity and reliability analyzing method based on nonlinear impairments theory as claimed in claim 7,
Be characterized in that: the rain load is calculated by following steps:
(1) the average rain load F that truss bridge a cycle is subject to is calculatedrain, then Frain=Prain·A；In formula, rain presses Prain；Bridge
Face area A；Prain=g ρ1H, wherein g is gravity constant, ρ1For rainwater density, unit area average product when h is torrential rain
Water depth.
9. a kind of girder steel bridge longevity and reliability analyzing method based on nonlinear impairments theory as claimed in claim 8,
Be characterized in that: according to traffic load, wind load, rain LOAD FOR truss bridge structure total stress, calculate in a monitoring cycle,
Equivalent stress width σ of the truss bridge under multi-load effectEValue:
In formula, k is variable-amplitude fatigue curve coefficients；σiFor a certain period truss bridge stress amplitude；niFor corresponding σiTruss bridge when stress amplitude
Loaded fatigue life cycle in one cycle.
10. a kind of girder steel bridge longevity and reliability analyzing method based on nonlinear impairments theory as claimed in claim 9,
Be characterized in that: specific step is as follows for step S5 calculating truss bridge service life and reliability:
(1) truss bridge service life NfAre as follows:
Nfi=9.384K (1.01 σ0-σi)1-A·Ri-1
(2) its use reliability of truss bridge R are as follows:
In formula, Ri-1Its structure existing damage safety degree when starting for a cycle；σiFor the lower knot of multi-load effect in a cycle
Structure stress amplitude；σ0For fatigue limit；A, K is constant；niFor corresponding σiTruss bridge loaded fatigue in one cycle when stress amplitude
Cycle-index.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113128033A (en) * | 2021-04-01 | 2021-07-16 | 河北大学 | High-strength steel fatigue life prediction method based on nonequivalent accumulated damage |
| CN114136264A (en) * | 2021-11-24 | 2022-03-04 | 中国铁道科学研究院集团有限公司铁道建筑研究所 | Method for testing relative corner of beam end of railway bridge |
| CN116311150A (en) * | 2023-01-03 | 2023-06-23 | 中设科欣设计集团有限公司 | Bridge damage assessment and early warning method based on specific vehicle deflection monitoring |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003131559A (en) * | 2001-10-23 | 2003-05-09 | Nkk Corp | Bridge beam design system for steel bridge |
| CN102567632A (en) * | 2011-12-22 | 2012-07-11 | 上海交通大学 | Shore bridge structure wind vibration fatigue life forecasting method based on accumulated damage of probability |
| CN102621220A (en) * | 2012-03-16 | 2012-08-01 | 东南大学 | Method for predicting remaining useful life of steel box girder bridge top plate-longitudinal rib welding detail |
-
2018
- 2018-12-29 CN CN201811639017.6A patent/CN109635497B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003131559A (en) * | 2001-10-23 | 2003-05-09 | Nkk Corp | Bridge beam design system for steel bridge |
| CN102567632A (en) * | 2011-12-22 | 2012-07-11 | 上海交通大学 | Shore bridge structure wind vibration fatigue life forecasting method based on accumulated damage of probability |
| CN102621220A (en) * | 2012-03-16 | 2012-08-01 | 东南大学 | Method for predicting remaining useful life of steel box girder bridge top plate-longitudinal rib welding detail |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113128033A (en) * | 2021-04-01 | 2021-07-16 | 河北大学 | High-strength steel fatigue life prediction method based on nonequivalent accumulated damage |
| CN114136264A (en) * | 2021-11-24 | 2022-03-04 | 中国铁道科学研究院集团有限公司铁道建筑研究所 | Method for testing relative corner of beam end of railway bridge |
| CN114136264B (en) * | 2021-11-24 | 2024-03-12 | 中国铁道科学研究院集团有限公司铁道建筑研究所 | Railway bridge beam end relative rotation angle testing method |
| CN116311150A (en) * | 2023-01-03 | 2023-06-23 | 中设科欣设计集团有限公司 | Bridge damage assessment and early warning method based on specific vehicle deflection monitoring |
| CN116311150B (en) * | 2023-01-03 | 2023-11-14 | 中设科欣设计集团有限公司 | Bridge damage assessment and early warning method based on specific vehicle deflection monitoring |
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