CN102967263B - A kind of deflection of bridge span-corner integral measurement method - Google Patents

Abstract

The present invention relates to a kind of deflection of bridge span-corner integral measurement method, at bridge structural deflection measuring point to be measured place fixed signal transmitter A, guarantee that the light path of two generating lasers of signal transmitter A is in alignment and longitudinally oppositely launch along bridge; At each fixing a set of signal collecting device B of bridge two sides stationary reference point, and the laser that signal transmitter A is sent can be received by the receiving screen of signal collecting device B; Two signal collecting device B are connected with computing machine C; Computing machine C carries out the computing of spot displacement according to fixed frequency synchronous acquisition hot spot data.Measuring method of the present invention, generating laser is arranged symmetrically in structural deflection measuring point place to be measured, solve the problem that laser corner brings error, and recorded amount of deflection and corner at a measuring point simultaneously, generating laser is fixedly connected with detected part, there is no degree of freedom, when image capture device gathers representation of laser facula by fixed frequency, can kinetic measurement be carried out.

Description

A kind of deflection of bridge span-corner integral measurement method

Technical field

The present invention relates to bridge machinery and monitoring technical field, is a kind of deflection of bridge span-corner integral measurement method specifically.Espespecially deflection of bridge span-corner (amount of deflection and corner) integrated dynamic measurement method.

Background technology

Amount of deflection is the important parameter that bridge structure is all paid special attention in intensity, rigidity, the large key issue of stability three, whether direct reflection bridge structure exceeds risk range in operation state, so when the safety case of assessment one bridge block, amount of deflection is most important.Under the demand of deflection metrology, domestic and international researchist has developed many deflection metrology methods, and laser measurement is exactly wherein a kind of.The collimation of laser is high, not easily disperses, can realize remote measurement, and many software engineering researchers invent are based on the bridge structure displacement test system of laser facula identification.But the problem that laser brings is exactly its sensitivity to corner, no matter generating laser is fixed in bridge structure or is fixed on the stationary reference point away from structure, even if generating laser has a faint rotation, after distance is amplified, also can bring very large error.

The patent No. is ZL200510020375.5, grant number is the adaptive damping hinge arrangement that CN1297798C disclosed " two dimension, large range laser amount of deflection/displacement measurement method and device " proposes a kind of fixed laser, when making bridge generation corner, laser still keeps fixed pose, and when only having bridge to have an amount of deflection, generating laser just moves up and down.In the static state of carrying out loading test at bridge or quasistatic process, this laser fixed form can realize, to the avoidance of corner, accurately measuring amount of deflection.But, the bridge operation phase can be born various types of vehicles for a long time and be impacted, be in a transient equilibrium for a long time, the upper pendulum bar of hinge can be subject to the impact from bridge, and the system of upper draft link and ball pivot composition is a free state, after such words upper pendulum bar is subject to the impulsive force from bridge, laser self will produce a random vibration, causes measuring and loses efficacy.

The patent No. is ZL0810070076.6, grant number is that CN101339003B disclosed " great structure horizontal two-dimensional displacement automatic measuring equipment and method " proposes and utilizes Action of Gravity Field that the sensitivity of generating laser to corner is avoided in the suspention of laser instrument rope, this mode can realize static measurement to the two-dimension displacement of the bridge tower of guy system in surface level, but cannot measure deflection of bridge span.The method is make laser be in a free state equally, and the dynamic displacement of bridge tower is difficult to transmit.

The patent No. is ZL200920126826.7, the patent No. for ZL200920126829.0 and patent No. content disclosed in ZL201020226330.X be also utilize Laser Measuring amount of deflection, institute's employing way to connect with spring or the mode such as suspension avoids the sensitivity of laser to corner.This mode is also to meet static measurement.

What require along with detection technique improves constantly, and for carrying out some spectrum analyses or non-destructive tests, scientific research and detection unit often pay close attention to the dynamic parameter of bridge more.Bridge operation phase on-line checkingi or long-term dynamics monitoring all need to carry out kinetic measurement to its amount of deflection.Sum up existing patented technology above, the maximum problem of laser deflection metrology is the sensitivity of linear laser to corner, and the laser fixed sturcture after improving can be avoided the impact of corner but be difficult to realize kinetic measurement.

Summary of the invention

For the defect existed in prior art, the object of the present invention is to provide a kind of deflection of bridge span-corner integral measurement method, generating laser is arranged symmetrically with (symmetrical reverse layout) at structural deflection measuring point place to be measured, solve the problem that laser corner brings error, and recorded amount of deflection and corner at a measuring point simultaneously, generating laser is fixedly connected with detected part, does not have degree of freedom, can carry out kinetic measurement when image capture device gathers representation of laser facula by fixed frequency.

For reaching above object, the technical scheme that the present invention takes is:

A kind of deflection of bridge span-corner integral measurement method, is characterized in that, comprise the following steps:

At bridge structural deflection measuring point to be measured, place is fixedly installed signal transmitter A, described signal transmitter A comprises: two generating lasers 2, two generating lasers 2 are arranged by clamper 1 symmetrical reverse, be fixed on bridge detected part by clamper 1, adjustment clamper 1 is guaranteed that the light path of two generating lasers 2 is in alignment and is longitudinally oppositely launched along bridge;

At each fixing a set of signal collecting device B for gathering laser facula of bridge two sides stationary reference point, described signal collecting device B comprises: guard shield 4, its front end is provided with receiving screen 3, its rear end is provided with the video camera 5 as image capture device, its underpart is provided with support 6, and the laser regulating support 6 that signal transmitter A is sent can be received screen 3 and receive;

Two signal collecting device B are connected with computing machine C and are controlled by computing machine C simultaneously;

Computing machine C is according to certain fixed frequency synchronous acquisition and store the representation of laser facula data that two signal collecting device B gather, and carries out the computing of laser facula displacement.

On the basis of technique scheme, described receiving screen 3 is made by translucent frosted glass.

On the basis of technique scheme, the center line of the camera lens of video camera 5 keeps vertical with receiving screen 3.

On the basis of technique scheme, the computing of described laser facula displacement comprises the following steps:

If bridge there occurs amount of deflection w and rotational angle theta at amount of deflection measuring point simultaneously, through computing machine C process, it is y that First signal collecting device B records the vertical displacement of hot spot ₁, it is y that second signal collecting device B records the vertical displacement of hot spot ₁, amount of deflection measuring point is l from the distance of First signal collecting device B ₁, the distance from second signal collecting device B is l ₂,

Then press the value θ that relation of plane tries to achieve amount of deflection w and corner:

$w=\frac{y_1{l}_2+y_2{l}_1}{l_1+l_2}$

$\mathrm{\θ}\≈\tan \mathrm{\θ}=\frac{y_2-y_1}{l_1+l_2}.$

On the basis of technique scheme, computing machine C calculates the vertical displacement y of laser facula on receiving screen 3 by gravity model appoach, is the video camera of M × N for a pixel, and corresponding hot spot is gathering the location of pixels value Y in picture, is determined by following formula:

$Y=\frac{\underset{i=1}{\overset{M}{\mathrm{\Σ}}}\underset{j=1}{\overset{N}{\mathrm{\Σ}}}f(i,j)\×j}{\underset{i=1}{\overset{M}{\mathrm{\Σ}}}\underset{j=1}{\overset{N}{\mathrm{\Σ}}}f(i,j)}$

Wherein, f (i, j) represents the gray-scale value of this pixel, and i represents lateral coordinates value, and j represents longitudinal coordinate value;

In order to accurately reflect that the actual displacement of hot spot also needs to have demarcated the actual range representated by each pixel in advance, two signal collecting device B are the same, and in picture, pixel and actual range reduction coefficient k value are constant, k=h _mark/ H _mark, h _markrepresent the true altitude value of receiving screen 3, H _markrepresent receiving screen height in the picture;

Under structure does not have bearing load stationary state, First signal collecting device B and second location of pixels that signal collecting device B calculates spot center vertical direction by gravity model appoach is respectively Y ₁₀, Y ₂₀, then press formula y ₁=(Y ₁-Y ₁₀) × k and y ₂=(Y ₂-Y ₂₀) × k calculates the shift value of hot spot, Y ₁, Y ₂represent the location of pixels of First and second signal collecting device B current state spot center vertical direction respectively.

Deflection of bridge span of the present invention-corner integral measurement method, by fixing two generating lasers in structural deflection measuring point place to be measured symmetrical reverse, at each fixing a set of image capture device for gathering laser facula of bridge two sides stationary reference point, control two cover image capture devices with a computing machine simultaneously, two cover image capture devices are made to keep synchronously gathering representation of laser facula by certain fixed frequency, the positional value of laser facula on receiving screen is calculated by Computer, and then extrapolate amount of deflection and the corner value of system point to be measured with the position of two laser faculas simultaneously, realize deflection of bridge span-corner integration kinetic measurement.

The present invention compared with prior art, has the following advantages and high-lighting effect:

Employing generating laser is arranged symmetrically with, and not only solves the problem that laser corner brings error, and has recorded amount of deflection and corner at a measuring point simultaneously;

Generating laser is fixedly connected with detected part, does not have degree of freedom, can carry out kinetic measurement when image capture device gathers representation of laser facula by fixed frequency.

Accompanying drawing explanation

The present invention has following accompanying drawing:

Fig. 1 is the schematic diagram of deflection of bridge span-corner integrated measurer.

Fig. 2 is signal transmitter A schematic diagram.

Fig. 3 is signal collecting device B schematic diagram.

Fig. 4 is the principle schematic of integral measurement method of the present invention, wherein, Fig. 4 a represent measuring point occur simultaneously amount of deflection and corner change after laser optical path situation, Fig. 4 b represent the laser optical path situation that measuring point generation corner change, Fig. 4 c represent occur amount of deflection change laser optical path situation.

Test curve when Fig. 5 is bridge 60km/h preventing test measured by the embodiment of the present invention, wherein, Fig. 5 a is span centre measuring point dynamic deflection curve, and Fig. 5 b is span centre measuring point dynamic rotational angle curve.

Embodiment

Below in conjunction with accompanying drawing, the present invention is described in further detail.

As shown in Figure 1, deflection of bridge span of the present invention-corner integral measurement method, comprises the following steps:

At bridge structural deflection measuring point to be measured, place is fixedly installed signal transmitter A, as shown in Figure 2, described signal transmitter A comprises: two generating lasers 2, two generating lasers 2 are arranged by clamper 1 symmetrical reverse, be fixed on bridge detected part by clamper 1, adjustment clamper 1 is guaranteed that the light path of two generating lasers 2 is in alignment and is longitudinally oppositely launched along bridge;

At each fixing a set of signal collecting device B for gathering laser facula of bridge two sides stationary reference point, such as respectively be provided with a signal collecting device B at bridge two pier stationary reference point, as shown in Figure 3, described signal collecting device B comprises: guard shield 4, its front end is provided with receiving screen 3, its rear end is provided with the video camera 5 as image capture device, and its underpart is provided with support 6, and the laser regulating support 6 that signal transmitter A is sent can be received screen 3 and receive;

Described receiving screen 3 is made by translucent frosted glass, is used for receiving the hot spot of generating laser 2;

Described guard shield 4 for the relative position of fixed cameras 5 and receiving screen 3, and shields to video camera 5;

Described video camera 5 gathers the picture of hot spot on receiving screen 3 after imaging that generating laser 2 projects, and the center line of the camera lens of video camera 5 keeps vertical with receiving screen 3;

Described support 6 is used for fixing guard shield 4;

Be connected with computing machine C by two signal collecting device B and controlled by computing machine C simultaneously, computing machine C is connected with two signal collecting device B by data line simultaneously, processes the view data that signal collecting device B transmits;

Computing machine C is according to certain fixed frequency synchronous acquisition and store the representation of laser facula data that two signal collecting device B gather, and carries out the computing of laser facula displacement.

On the basis of technique scheme, the computing of described laser facula displacement comprises the following steps:

If bridge there occurs amount of deflection w and rotational angle theta at amount of deflection measuring point simultaneously, through computing machine C process, it is y that First signal collecting device B records the vertical displacement of hot spot ₁, it is y that second signal collecting device B records the vertical displacement of hot spot ₂, amount of deflection measuring point is l from the distance of First signal collecting device B ₁, the distance from second signal collecting device B is l ₂,

Then press the value θ that relation of plane tries to achieve amount of deflection w and corner:

$w=\frac{y_1{l}_2+y_2{l}_1}{l_1+l_2}$

$\mathrm{\θ}\≈\tan \mathrm{\θ}=\frac{y_2-y_1}{l_1+l_2}.$

On the basis of technique scheme, computing machine C calculates the laser facula vertical displacement on receiving screen 3 (vertical displacement value) y by gravity model appoach, be the video camera of M × N for a pixel, corresponding hot spot is gathering the location of pixels value Y in picture, is determined by following formula:

$Y=\frac{\underset{i=1}{\overset{M}{\mathrm{\Σ}}}\underset{j=1}{\overset{N}{\mathrm{\Σ}}}f(i,j)\×j}{\underset{i=1}{\overset{M}{\mathrm{\Σ}}}\underset{j=1}{\overset{N}{\mathrm{\Σ}}}f(i,j)}$

Wherein, f (i, j) represents the gray-scale value of this pixel, and i represents lateral coordinates value, and j represents longitudinal coordinate value;

In order to accurately reflect that the actual displacement of hot spot also needs to have demarcated the actual range representated by each pixel in advance, two signal collecting device B are the same, and in picture, pixel and actual range reduction coefficient k value are constant, k=h _mark/ H _mark, h _markrepresent the true altitude value of receiving screen 3, H _markrepresent receiving screen height in the picture;

Under structure does not have bearing load stationary state, First signal collecting device B and second location of pixels that signal collecting device B calculates spot center vertical direction by gravity model appoach is respectively Y ₁₀, Y ₂₀, then press formula y ₁=(Y ₁-Y ₁₀) × k and y ₂=(Y ₂-Y ₂₀) × k calculates the shift value of hot spot, Y ₁, Y ₂represent the location of pixels of First and second signal collecting device B current state spot center vertical direction respectively.

It is below an embodiment.

The present embodiment with a certain prestressed concrete in certain city across Jiang Qiaowei example (main span is for 80m).

Fixed signal transmitter A on measuring point between this bridge main span centre, debugging clamper 1 makes that the light path of two generating lasers 2 is in alignment longitudinally launches towards two sides along bridge; At bridge two, pier stationary reference point is respectively provided with a signal collecting device B, and the laser regulating support 6 that signal transmitter A is sent can be received screen 3 and receive; Two signal collecting device B are connected with computing machine C and are controlled by computing machine C simultaneously; Computing machine C can store according to fixed frequency 8Hz synchronous acquisition the light spot image data that two signal collecting device B gather;

The vertical displacement value y of laser facula on receiving screen 3 is calculated by gravity model appoach.Video camera 5 pixel is 1280 × 1024 pixels, in order to accurately reflect that the actual displacement of hot spot needs to have demarcated the actual range representated by each pixel in advance.Two signal collecting device B are the same, and in picture, pixel and actual range reduction coefficient k value are constant.K=h _mark/ H _mark, h mark represents the true altitude value of receiving screen 3, and h=800mm, H mark represents receiving screen height in the picture, and H=1024pixels, so k=0.78mm/pixel.Under structure does not have bearing load stationary state, First signal collecting device B and second location of pixels that signal collecting device B calculates spot center vertical direction by gravity model appoach is respectively Y ₁₀=500.34, Y ₂₀=509.78.By formula y ₁=(Y ₁-Y ₁₀) × k and y ₂=(Y ₂-Y ₂₀) × k calculates the shift value of hot spot, Y ₁, Y ₂represent the location of pixels of First and second signal collecting device B current state spot center vertical direction respectively.

Principle of the present invention as shown in Figure 4, Fig. 4 a represent measuring point there is corner simultaneously after laser optical path situation, it be by measuring point generation corner (Fig. 4 b) and occur amount of deflection (4c) result be coupled to form.Suppose that bridge there occurs amount of deflection w and rotational angle theta at amount of deflection measuring point simultaneously, through computing machine C process, it is y that First signal collecting device B records the vertical displacement of hot spot ₁, it is y that second signal collecting device B records the vertical displacement of hot spot ₂, amount of deflection measuring point is l from the distance of First signal collecting device B ₁, the distance from second signal collecting device B is l ₂, so amount of deflection w and rotational angle theta meet following relation:

y ₁=w-l ₁tanθ y ₂=w+l ₂tanθ

Through conversion can be in the hope of amount of deflection w and rotational angle theta:

$w=\frac{y_1{l}_2+y_2{l}_1}{l_1+l_2}$

$\mathrm{\θ}\≈\tan \mathrm{\θ}=\frac{y_2-y_1}{l_1+l_2}.$

Fig. 5 is that this bridge passes through this bridge with 60km/h, the dynamic deflection curve (5a) of the span centre measuring point recorded by the method and dynamic rotational angle curve (5b) side by side at the vehicle that two 30t are heavy.

The content be not described in detail in this instructions belongs to the known prior art of professional and technical personnel in the field.

Claims (4)

1. deflection of bridge span-corner integral measurement method, is characterized in that, comprise the following steps:

At bridge structural deflection measuring point to be measured, place is fixedly installed signal transmitter A, described signal transmitter A comprises: two generating lasers (2), two generating lasers (2) are arranged by clamper (1) symmetrical reverse, be fixed on bridge detected part by clamper (1), adjustment clamper (1) is guaranteed that the light path of two generating lasers (2) is in alignment and is longitudinally oppositely launched along bridge;

At each fixing a set of signal collecting device B for gathering laser facula of bridge two sides stationary reference point, described signal collecting device B comprises: guard shield (4), its front end is provided with receiving screen (3), its rear end is provided with the video camera (5) as image capture device, its underpart is provided with support (6), and the laser regulating support (6) that signal transmitter A is sent can be received screen (3) and receive;

Two signal collecting device B are connected with computing machine C and are controlled by computing machine C simultaneously;

Computing machine C is according to certain fixed frequency synchronous acquisition and store the representation of laser facula data that two signal collecting device B gather, and carries out the computing of laser facula displacement;

The computing of described laser facula displacement comprises the following steps:

If bridge there occurs amount of deflection w and rotational angle theta at amount of deflection measuring point simultaneously, through computing machine C process, it is y that First signal collecting device B records the vertical displacement of hot spot ₁, it is y that second signal collecting device B records the vertical displacement of hot spot ₂, amount of deflection measuring point is l from the distance of First signal collecting device B ₁, the distance from second signal collecting device B is l ₂,

Then press the value θ that relation of plane tries to achieve amount of deflection w and corner:

$w=\frac{y_1{l}_2+y_2{l}_1}{l_1+l_2}$

$\mathrm{\θ}\≈\tan \mathrm{\θ}=\frac{y_2-y_1}{l_1+l_2}.$

2. deflection of bridge span-corner integral measurement method as claimed in claim 1, is characterized in that: described receiving screen (3) is made by translucent frosted glass.

3. deflection of bridge span-corner integral measurement method as claimed in claim 1, is characterized in that: center line and the receiving screen (3) of the camera lens of video camera (5) keep vertical.

4. deflection of bridge span-corner integral measurement method as claimed in claim 1, it is characterized in that: computing machine C calculates the vertical displacement y of laser facula on receiving screen (3) by gravity model appoach, be the video camera of M × N for a pixel, corresponding hot spot is gathering the location of pixels value Y in picture, is determined by following formula:

$Y=\frac{\underset{i=1}{\overset{M}{\mathrm{\Σ}}}\underset{j=1}{\overset{N}{\mathrm{\Σ}}}f(i,j)\×j}{\underset{i=1}{\overset{M}{\mathrm{\Σ}}}\underset{j=1}{\overset{N}{\mathrm{\Σ}}}f(i,j)}$

Wherein, f (i, j) represents the gray-scale value of this pixel, and i represents lateral coordinates value, and j represents longitudinal coordinate value;

In order to accurately reflect that the actual displacement of hot spot also needs to have demarcated the actual range representated by each pixel in advance, two signal collecting device B are the same, and in picture, pixel and actual range reduction coefficient k value are constant, k=h _mark/ H _mark, h _markrepresent the true altitude value of receiving screen (3), H _markrepresent receiving screen height in the picture;

Under structure does not have bearing load stationary state, First signal collecting device B and second location of pixels that signal collecting device B calculates spot center vertical direction by gravity model appoach is respectively Y ₁₀, Y ₂₀, then press formula y ₁=(Y ₁-Y ₁₀) × k and y ₂=(Y ₂-Y ₂₀) × k calculates the shift value of hot spot, Y ₁, Y ₂represent the location of pixels of First and second signal collecting device B current state spot center vertical direction respectively.