阅读说明：本技术 高速公路桥梁动态计重及监测一体化装置 (Dynamic weighing and monitoring integrated device for highway bridge ) 是由 赵春柳 司召鹏 毛邦宁 徐贲 龚华平 康娟 王兆坤 金尚忠 于 2021-07-07 设计创作，主要内容包括：本发明涉及基于高速公路桥梁动态计重及监测一体化装置,包括一台窄线宽激光器、两个耦合器、一个声光调制器、一个掺铒光纤放大器、一个滤波器、一个环形器、两条减速带、若干条宽带弱反射光纤光栅序列、若干个摄像头、一个平衡探测器、一个数据采集卡、一个工控机；不同的载重车辆经过减速带时会产生不同的振动信号,宽带弱反射光纤光栅序列会很好的感应到这种振动信号,并将感受到的振动信号输送到探测解调装置之中,探测解调装置解调出振动信号的振动频率,由载重车辆重量与振动信号频率的平方成反比得到载重车辆的重量,通过工控机连接到摄像头即实现了高速公路桥梁动态计重及监测一体化。(The invention relates to a dynamic weighing and monitoring integrated device based on a highway bridge, which comprises a narrow linewidth laser, two couplers, an acousto-optic modulator, an erbium-doped fiber amplifier, a filter, a circulator, two deceleration strips, a plurality of broadband weak reflection fiber grating sequences, a plurality of cameras, a balance detector, a data acquisition card and an industrial personal computer; different load-carrying vehicles can produce different vibration signals when passing through the deceleration strip, the broadband weak reflection fiber grating sequence can well sense the vibration signals, the sensed vibration signals are conveyed to the detection demodulation device, the detection demodulation device demodulates the vibration frequency of the vibration signals, the weight of the load-carrying vehicles is obtained by inversely proportional of the weight of the load-carrying vehicles and the square of the frequency of the vibration signals, and the industrial personal computer is connected to the camera, so that the dynamic weighing and monitoring integration of the highway bridge is realized.)

1. Based on highway bridge developments meter heavily and monitoring integrated device, its characterized in that is with the following step:

the method comprises the following steps: selecting an optical pulse generating device which comprises a narrow linewidth laser, a coupler, an acousto-optic modulator, an erbium-doped fiber amplifier, a filter and a detection demodulating device which comprises a circulator, a coupler, a balance detector, a data acquisition card and an industrial personal computer, selecting two deceleration strips, a plurality of broadband weak reflection fiber grating sequences and a plurality of cameras, wherein the two deceleration strips are laid at two ends of a highway weight measuring section or an inlet and an outlet of a bridge, the plurality of broadband weak reflection fiber grating sequences are laid in a highway weight measuring lane or on the bridge, the camera is arranged above the road surface or the bridge, and the detection demodulating device, the narrow linewidth laser and the like are laid at the edge of the highway base or at a bridge guardrail;

step two: the output end of a narrow linewidth laser in an optical pulse generating device is connected with the input end of a first coupler, the splitting ratio of the first coupler is 1:99, 99% of the output end of the first coupler is connected with the input end of an acousto-optic modulator, 1% of the output end of the first coupler is connected with the input end of a second coupler, the output end of the acousto-optic modulator is connected with the input end of a filter through an erbium-doped fiber amplifier, the output end of the filter is connected with a first port of a circulator in a detection demodulation device, a second port of the circulator is connected with a broadband weak reflection fiber grating sequence, a third port of the circulator is connected with an input port of the second coupler, the coupling ratio of the second coupler is 50:50, and the input end of the second coupler respectively receives a narrow linewidth laser beam with the splitting ratio of 1% of the first coupler and a light beam reflected back by the broadband weak reflection fiber grating sequence, in the second coupler, the two signals are coherent and the difference frequency signal is processed by the detecting demodulator, and the output of the detecting demodulator is connected to the input of several cameras. Broadband weak reflection fiber grating sequences are buried between the two deceleration strips, the broadband weak reflection fiber grating sequences are also laid under the deceleration strips, and the number of laid optical fibers is the same as that of lanes of a highway or a bridge;

step three: when a vehicle passes through the first deceleration strip, the deceleration strip enables the vehicle to vibrate, different vibration signals can be generated due to different vehicle weights, the broadband weak reflection fiber bragg grating sequence is very sensitive to vibration information, and the vibration information can be collected and transmitted back to the detection and demodulation device;

wherein the signals received in the demodulation apparatus are:

I_riis a received signal of a probe demodulation apparatus, I_iIs the reflected light of a broadband weak reflection fiber grating sequence, I₀Is the light intensity of the light source, t is the time,the phase difference between the broadband weak reflection fiber grating sequence and the light source is obtained, the delta f is the frequency shift brought by the acousto-optic modulator, and the reflection signal contains the intensity and phase information of each fiber grating;

the frequency shift and time brought by the acousto-optic modulator between the broadband weak reflection fiber grating sequences are fixed, and the difference frequency signal is only the phase difference between the broadband weak reflection fiber grating and the light sourceThe change occurs when it changes, and the relative change in intensity between the i and i +1 th beat signals represents the phase change resulting from the coupling grating between the i and i +1 th fiber gratings, which can be described as:

the phase change along the fiber can therefore be calculated by cross-correlation between the difference frequency signals of the two broadband weak reflection fiber grating sequences;

after the vibration event of the optical fiber among the broadband weak reflection optical fiber grating sequences passes through the detection demodulation device, the amplitude and frequency information of the vibration signal can be obtained;

step four: after the amplitude and frequency information of the vibration signal is demodulated by the detection and demodulation device, the weight of the vehicle passing through the broadband weak reflection fiber grating sequence can be deduced according to the vibration frequency of the vibration signal, the vehicle can be simplified into free vibration when passing through a deceleration strip, and the vibration frequency is irrelevant to the initial condition and is only relevant to the inherent characteristic of the system;

when the vehicle freely vibrates through the deceleration strip, the relationship between the vibration frequency and the mass can be expressed by the following formula:

k is the rigidity of the object and is only related to the attribute of the object, f is the vibration frequency of the vehicle passing through the deceleration strip, the mass obtained by the formula (3) is inversely proportional to the square of the vibration frequency, when the vibration frequency of the passing vehicle is measured by the broadband weak reflection fiber grating sequence, the weight information of the vehicle can be obtained, after the vibration frequency and the weight information of the vehicle are demodulated by the detection and demodulation device, the information is stored in an industrial personal computer, when the weight of the vehicle exceeds the road weight limit or the bridge weight limit, a camera connected with the industrial personal computer takes a picture, and the vehicle information is uploaded to a network system of a traffic police team;

the system can measure the weight of a vehicle in running by utilizing a broadband weak reflection fiber grating sequence, and the industrial personal computer is connected with a camera to photograph an overloaded and overspeed vehicle, so that the integration of dynamic weighing and monitoring of a highway bridge is realized.

2. The highway bridge-based dynamic weight-counting and monitoring integrated device is characterized by comprising an optical pulse generating device, a detection demodulating device, two deceleration strips, a plurality of broadband weak reflection optical fiber grating sequences and a plurality of cameras; the optical pulse generating device comprises a narrow linewidth laser, two couplers, an acousto-optic modulator, an erbium-doped fiber amplifier and a filter; the detection demodulation device comprises a circulator, a balance detector, a data acquisition card and an industrial personal computer; the narrow linewidth laser in the optical pulse generating device is connected into the first coupler through a single-mode optical fiber; the channel with 99 percent of splitting ratio of the first coupler is connected into the erbium-doped fiber amplifier through the acousto-optic modulator, and the channel with 1 percent of splitting ratio is connected into the second coupler; the erbium-doped fiber amplifier is connected with a first port of a circulator in the detection and demodulation device through a filter; a second port of a circulator in the detection demodulation device is connected to a broadband weak reflection fiber grating sequence, and a third port of the circulator is connected with a second coupler; the second coupler is connected to the data acquisition card through a balanced detector; the data acquisition card is connected with the camera through an industrial personal computer; the two deceleration strips are laid at the two ends of the highway weight measuring section or the inlet and the outlet of the bridge; the plurality of broadband weak reflection fiber bragg grating sequences are laid in the high-speed weight measuring lane or on the bridge; the camera is arranged above a road surface or a bridge, and narrow-line-width lasers, an industrial personal computer and the like are laid on the edge of the high-speed roadbed or the bridge guardrail.

Technical Field

The invention belongs to the technical field of optical fiber sensing, and particularly relates to a dynamic weighing and monitoring integrated device based on a highway bridge.

Background

Along with the continuous development of economic society of China, the construction mileage of high-speed bridges in China is continuously refreshed every year, the construction of the major civil engineering causes the freight volume of customs, cement plants, stone plants and the like to be increased, and simultaneously causes the places for trading according to weight to be continuously increased, so that the overload problem and the weight measurement problem of transport vehicles come along, the overweight of the transport vehicles can not only damage the roadbed and bridge structures of the high-speed roads, but also bring great threat to the life and property safety of people. A great problem caused by the rapid development of road traffic safety is how to effectively and safely manage overloaded vehicles.

In recent years, research and development of overload detection systems have made significant progress, and various detection systems are continuously researched and applied, and the existing technologies related to overload detection include: automobile wheel load detecting system, the fast highway section detecting system that weighs that does not stop, the automobile wheel load detecting system of one-level internet of things technique etc, the most commonly used vehicle weighing system parks the meter weight at the charge gateway promptly in the high-speed bridge now, when the vehicle drives in the weighing scale board, the vehicle must thoroughly stop and reach the center of weighing scale board position, the deformation volume that brings through measuring the vehicle for the weighing scale board measures the weight of vehicle, the biggest advantage of this system is exactly to measure the accuracy, but this measuring device is consuming time longer, current efficiency is very low, can all arouse the phenomenon of blocking up at the charge gate of many, lead to the vehicle speed of passing slow, and this weighing system wastes time and energy.

Because the limitation of traditional check weighing system, the research and development of the check weighing system that does not stop receives people's attention more and more, check weighing system that does not stop is mainly applied to highway entry and bridge entrance, be used for detecting the dynamic weight of car, the condition that the vehicle was overweight the traveling in road bridge can effectively in time be prevented to this system, can avoid well because the overweight damage of bringing road bridge of car, but the research of this system mostly can not promote in all roads comprehensively, because the research of this system is still imperfect, the degree of accuracy of weighing is also not high, also be not suitable for in the road bridge of high flow such as holidays.

The optical fiber grating is a wavelength modulation type optical fiber sensor, which utilizes the photosensitivity of optical fiber materials to form a permanent optical fiber device with a periodically-changed refractive index along the axial direction of a fiber core by an ultraviolet exposure method, and the essence is to form a narrow-band reflection (or transmission) type optical filter in the fiber core, and the sensing process based on the optical fiber grating is to obtain sensing information by modulating the central wavelength of external parameters (such as stress, vibration, temperature and the like). Center lambda of fiber grating_BThe relationship with strain ε and temperature T can be simplified as a formulaAccording to the wavelength drift caused by the change of stress, vibration, temperature and the like, the fiber grating can be made into a fiber grating sensor for detecting various parameters such as stress, strain, pressure, vibration, temperature and the like.

The invention provides a dynamic weighing and monitoring integrated device for a highway bridge, aiming at the problems of low traffic rate, long time consumption and the like of the traditional high-speed bridge weight measuring device. The invention has the advantages of high accuracy, high measuring speed, capability of carrying out multi-parameter measurement and weight measurement and monitoring integration, and the like.

Disclosure of Invention

Aiming at the problems of low traffic rate and long time consumption of the traditional high-speed bridge weight measuring device, the invention provides the dynamic weight counting and monitoring integrated device for the high-speed bridge, which has the advantages of high measuring speed, accurate measurement and parallel measurement and monitoring.

The method adopted for solving the technical problem comprises the following steps:

the method comprises the following steps: selecting an optical pulse generating device which comprises a narrow linewidth laser, a coupler, an acousto-optic modulator, an erbium-doped fiber amplifier, a filter and a detection demodulating device which comprises a circulator, a coupler, a balance detector, a data acquisition card and an industrial personal computer, selecting two deceleration strips, a plurality of broadband weak reflection fiber grating sequences and a plurality of cameras, wherein the two deceleration strips are laid at two ends of a highway weight measuring section or an inlet and an outlet of a bridge, the plurality of broadband weak reflection fiber grating sequences are laid in a highway weight measuring lane or on the bridge, the camera is arranged above the road surface or the bridge, and the detection demodulating device, the narrow linewidth laser and the like are laid at the edge of the highway base or at a bridge guardrail.

Step two: the output end of a narrow linewidth laser in an optical pulse generating device is connected with the input end of a first coupler, the splitting ratio of the first coupler is 1:99, 99% of the output end of the first coupler is connected with the input end of an acousto-optic modulator, 1% of the output end of the first coupler is connected with the input end of a second coupler, the output end of the acousto-optic modulator is connected with the input end of a filter through an erbium-doped fiber amplifier, the output end of the filter is connected with a first port of a circulator in a detection demodulation device, a second port of the circulator is connected with a broadband weak reflection fiber grating sequence, a third port of the circulator is connected with an input port of the second coupler, the coupling ratio of the second coupler is 50:50, and the input end of the second coupler respectively receives a narrow linewidth laser beam with the splitting ratio of 1% of the first coupler and a light beam reflected back by the broadband weak reflection fiber grating sequence, in the second coupler, the two signals are coherent and the difference frequency signal is processed by the detecting demodulator, and the output of the detecting demodulator is connected to the input of several cameras. The broadband weak reflection fiber grating sequences are buried between the two deceleration strips, the broadband weak reflection fiber grating sequences are also laid under the deceleration strips, and the number of laid optical fibers is the same as that of lanes of the highway or the bridge.

Step three: when the vehicle passes through a first deceleration strip, the deceleration strip can make the vehicle produce the vibration, and the difference of vehicle weight can produce different vibration signals, and the broadband weak reflection fiber grating sequence is very sensitive to vibration information, can gather vibration information and pass back and survey among the demodulation device.

Wherein the signals received in the demodulation apparatus are:

I_riis a received signal of a probe demodulation apparatus, I_iIs the reflected light of a broadband weak reflection fiber grating sequence, I₀Is the light intensity of the light source, t is the time,is the phase difference between the broadband weak reflection fiber grating sequence and the light source, and deltaf is the frequency shift brought by the acousto-optic modulator, and the reflected signal contains the intensity and phase information of each fiber grating.

The frequency shift and time brought by the acousto-optic modulator between the broadband weak reflection fiber grating sequences are fixed, and the difference frequency signal is only the phase difference between the broadband weak reflection fiber grating and the light sourceThe change occurs when it changes, and the relative change in intensity between the i and i +1 th beat signals represents the phase change resulting from the coupling grating between the i and i +1 th fiber gratings, which can be described as:

the phase change along the fiber can be calculated by cross-correlation between the difference frequency signals of the two broadband weak reflection fiber grating sequences.

After the vibration event of the optical fiber between the broadband weak reflection optical fiber grating sequences passes through the detection demodulation device, the amplitude and frequency information of the vibration signal can be obtained.

Step four: after the amplitude and frequency information of the vibration signal is demodulated by the detection and demodulation device, the weight of the vehicle passing through the broadband weak reflection fiber bragg grating sequence can be deduced according to the vibration frequency of the vibration signal, the vehicle can be simplified into free vibration when passing through a deceleration strip, and the vibration frequency is irrelevant to the initial condition and is only relevant to the inherent characteristic of the system.

When the vehicle freely vibrates through the deceleration strip, the relationship between the vibration frequency and the mass can be expressed by the following formula:

k is the rigidity of the object and is only related to the attribute of the object, f is the vibration frequency of the vehicle passing through the deceleration strip, the mass obtained by the formula (3) is inversely proportional to the square of the vibration frequency, when the vibration frequency of the passing vehicle is measured by the broadband weak reflection fiber grating sequence, the weight information of the vehicle can be obtained, after the vibration frequency and the weight information of the vehicle are demodulated by the detection and demodulation device, the information is stored in the industrial personal computer, when the weight of the vehicle exceeds the road weight limit or the bridge weight limit, the camera connected with the industrial personal computer can take pictures, and the vehicle information is uploaded to the network system of the traffic police team.

The system can measure the weight of a vehicle in running by utilizing a broadband weak reflection fiber grating sequence, and the industrial personal computer is connected with a camera to photograph an overloaded and overspeed vehicle, so that the integration of dynamic weighing and monitoring of a highway bridge is realized.

In order to realize the steps, the invention adopts the following structure, and is characterized by comprising an optical pulse generating device, a detection demodulating device, two deceleration strips, a plurality of broadband weak reflection fiber grating sequences and a plurality of cameras; the optical pulse generating device comprises a narrow linewidth laser, two couplers, an acousto-optic modulator, an erbium-doped fiber amplifier and a filter; the detection demodulation device comprises a circulator, a balance detector, a data acquisition card and an industrial personal computer; the narrow linewidth laser in the optical pulse generating device is connected into the first coupler through a single-mode optical fiber; the channel with 99 percent of splitting ratio of the first coupler is connected into the erbium-doped fiber amplifier through the acousto-optic modulator, and the channel with 1 percent of splitting ratio is connected into the second coupler; the erbium-doped fiber amplifier is connected with a first port of a circulator in the detection and demodulation device through a filter; a second port of a circulator in the detection demodulation device is connected to a broadband weak reflection fiber grating sequence, and a third port of the circulator is connected with a second coupler; the second coupler is connected to the data acquisition card through a balanced detector; the data acquisition card is connected with the camera through an industrial personal computer; the two deceleration strips are laid at the two ends of the highway weight measuring section or the inlet and the outlet of the bridge; the plurality of broadband weak reflection fiber bragg grating sequences are laid in the high-speed weight measuring lane or on the bridge; the camera is arranged above a road surface or a bridge, and narrow-line-width lasers, an industrial personal computer and the like are laid on the edge of the high-speed roadbed or the bridge guardrail.

The invention has the beneficial effects that:

1. utilize the vibration signal that the broadband weak reflection fiber grating sequence can be fine detects load-carrying vehicle, demodulates out the vibration frequency of vibration signal through detecting demodulation device, compares with traditional meter heavy mode, and the vehicle need not to park, has increased the current efficiency of vehicle, has also reduced the manpower and has used.

2. The device can well monitor the weight of the load-carrying vehicle, is connected with the camera through the industrial personal computer, and can realize integrated tests such as weight measurement of the vehicle, shooting and uploading of the violation vehicle and the like.

Drawings

Fig. 1 is a schematic view of a dynamic weighing and monitoring integrated device for an expressway bridge.

Detailed Description

The invention is further described below with reference to the accompanying drawings.

As shown in fig. 1, a schematic diagram of a dynamic weighing and monitoring integrated device for a highway bridge comprises a deceleration strip 1, a broadband weak reflection fiber grating sequence 2, a camera 3, a light pulse generating device 4, a narrow line width laser 5, a coupler 6, an acousto-optic modulator 7, an erbium-doped fiber amplifier 8, a filter 9, a detection demodulating device 10, a circulator 11, a coupler 12, a balance detector 13, a data acquisition card 14 and an industrial personal computer 15. The output end of a narrow linewidth laser 5 in an optical pulse generating device 4 is connected with the input end of a first coupler 6, the splitting ratio of the first coupler 6 is 1:99, 99% of the output end of the first coupler 6 is connected with the input end of an acousto-optic modulator 7, 1% of the output end is connected with the input end of a second coupler 12, the output end of the acousto-optic modulator 7 is connected with the input end of a filter 9 through an erbium-doped fiber amplifier 8, the output end of the filter 9 is connected with a first port of a circulator 11 in a detection demodulation device 10, a second port of the circulator 11 is connected with a broadband weak reflection fiber grating sequence 2, a third port of the circulator 11 is connected with an input port of the second coupler 12, the coupling ratio of the second coupler 12 is 50:50, the input end of the second coupler 12 respectively receives a narrow linewidth laser beam with the splitting ratio of 1% from the first coupler 6 and a light beam reflected by the broadband weak reflection fiber grating sequence 2, in the second coupler 12, the two signals are subjected to difference frequency, the generated difference frequency signal is subjected to signal processing by the detection demodulation device 10, and the output end of the detection demodulation device 10 is finally connected with the input ends of the plurality of cameras 3.

The working mode of the invention is as follows: a light beam emitted by a narrow-linewidth laser 5 in an optical pulse generating device 4 enters a coupler 6, the coupling ratio of the coupler 6 is 99:1, 99% of light sources enter an acousto-optic modulator 7, 1% of light sources enter a coupler 12, the light beam entering the acousto-optic modulator 7 is modulated into a pulse signal and generates a frequency shift, the generated pulse signal is amplified through an erbium-doped optical fiber amplifier 8, the amplified signal is filtered when passing through a filter 9, and then enters a broadband weak reflection optical fiber grating sequence 2 through a circulator 11. The deceleration strip 1 is connected with the broadband weak reflection fiber grating sequence 2, when a load-carrying vehicle passes through the deceleration strip 1, a vibration signal is generated, different load-carrying vehicles pass through the deceleration strip 1, different vibration signals are generated, the broadband weak reflection fiber grating sequence well senses the vibration signal and returns the sensed vibration signal to the circulator 11, then a difference frequency signal is formed in the coupler 12 together with a signal from the coupler 6, finally the difference frequency signal is demodulated by the detection demodulating device 10 to obtain the vibration frequency of the vibration signal, the formula (3) shows that the weight of the load-carrying vehicle is inversely proportional to the square of the vibration frequency, the weight of the load-carrying vehicle can be obtained from the obtained vibration signal, the industrial personal computer 15 in the detection demodulating device 10 is connected with the camera 3, when the weight of the load-carrying vehicle exceeds the limit of the road section or the bridge, the camera 3 takes a picture and uploads vehicle information, therefore, the integration of dynamic weighing and monitoring of the highway bridge is realized.

The device can realize that the key technology of highway bridge developments meter heavy and monitoring integration has:

1. detection demodulation device: the accuracy of demodulation is the key of the monitoring integrated device, the monitoring and demodulation of the vibration signal are directly related to the weight of the load-carrying vehicle, and after the phase information of two adjacent fiber gratings is obtained by the detection demodulation device, the vibration frequency of the vibration signal can be calculated through the cross correlation between difference frequency signals of two broadband weak reflection fiber grating sequences.

2. Narrow linewidth laser: for phase sensitive optical time domain reflectometer, the use of narrow linewidth laser will enhance the coherence effect between each scattered component in the pulse, and it is characterized by very narrow laser spectrum linewidth, linewidth < 10kHz, and coherence length up to over 100 hundred kilometers.

3. Broadband weak reflection fiber grating sequence: the broadband weak reflection fiber grating sequences manufactured by means of the tower pulling technology and ultraviolet exposure can provide strong signal light reflection light, all the broadband weak reflection fiber grating sequences have the same central wavelength and the same weak reflectivity, and the spatial interval between the adjacent broadband weak reflection fiber grating sequences determines the resolution of the system.

In a specific embodiment of the invention, the laser linewidth of the narrow linewidth laser is 1kHz, the pulse width output by the acousto-optic modulator is 300ns, the peak power is 8dBm, the coupling ratio of the two couplers is 99:1 and 50:50 respectively, the width of the broadband weak reflection fiber grating is 0.5nm, the reflectivity of the broadband weak reflection fiber grating is 1%, the interval between the two adjacent broadband weak reflection fiber gratings is 10m, 300 broadband weak reflection fiber gratings are recorded on each broadband weak reflection fiber grating sequence, and the broadband weak reflection fiber grating sequences are respectively laid on four roads.

It will be appreciated by persons skilled in the art that the embodiments of the invention described above and shown in the drawings are given by way of example only and are not limiting of the invention.

The objects of the invention have been fully and effectively accomplished. The functional and structural principles of the present invention have been shown and described in the examples, and the embodiments of the present invention may be subject to any changes or modifications without departing from the principles, and such changes and modifications are intended to fall within the scope of the invention as claimed.