阅读说明：本技术 一种基于光纤光栅的路基沉降监测装置 (Roadbed settlement monitoring device based on fiber bragg grating ) 是由 黄昌福 于 2019-10-31 设计创作，主要内容包括：本发明公开了一种基于光纤光栅的路基沉降监测装置,包括至少两个安装在监测面上的光纤光栅液位传感器；所述光纤光栅液位传感器包括圆柱形壳体,壳体的底部安装在底座上；所述壳体内部安装有矩形悬臂梁、圆柱形浮块、防冻液；所述矩形悬臂梁的上下两侧分别嵌入光纤光栅传感器,浮块悬浮于防冻液中,浮块与矩形悬臂梁的自由端铰接；所述光纤光栅传感器与光缆熔接串联,光缆连接光纤光栅解调仪,通过光纤光栅解调仪采集壳体内液位变化时矩形悬臂梁的应变,相邻的光纤光栅液位传感器壳体上段经通气管相连通,相邻的光纤光栅液位传感器壳体的下段经通液管相连通,让矩形悬臂梁产生弯曲变形,通液管连接自动液位控制器。(The invention discloses a roadbed settlement monitoring device based on fiber bragg gratings, which comprises at least two fiber bragg grating liquid level sensors arranged on a monitoring surface; the fiber bragg grating liquid level sensor comprises a cylindrical shell, wherein the bottom of the shell is arranged on a base; a rectangular cantilever beam, a cylindrical floating block and an antifreeze are arranged in the shell; the upper side and the lower side of the rectangular cantilever beam are respectively embedded with a fiber grating sensor, a floating block is suspended in the antifreeze solution, and the floating block is hinged with the free end of the rectangular cantilever beam; the fiber grating sensor is connected with the optical cable in series in a fusion mode, the optical cable is connected with the fiber grating demodulator, strain of the rectangular cantilever beam is collected through the fiber grating demodulator when the liquid level in the shell changes, the upper section of the adjacent fiber grating liquid level sensor shell is communicated through the air pipe, the lower section of the adjacent fiber grating liquid level sensor shell is communicated through the liquid pipe, the rectangular cantilever beam is enabled to generate bending deformation, and the liquid pipe is connected with the automatic liquid level controller.)

1. The utility model provides a road bed settlement monitoring devices based on fiber grating which characterized in that: the device comprises at least two fiber bragg grating liquid level sensors arranged on a monitoring surface; the fiber bragg grating liquid level sensor comprises a cylindrical shell, the bottom of the shell is arranged on a base, and the base is connected to a bottom plate arranged on a monitoring surface through a fixing screw rod; a rectangular cantilever beam, a cylindrical floating block and an antifreeze are arranged in the shell; the upper side and the lower side of the rectangular cantilever beam are respectively embedded with a fiber grating sensor, a floating block is suspended in the antifreeze solution, and the floating block is hinged with the free end of the rectangular cantilever beam; the fiber bragg grating liquid level sensors are connected with the optical cable in series in a fusion mode, the optical cable is connected with the fiber bragg grating demodulator, strain of the rectangular cantilever beam is collected through the fiber bragg grating demodulator when the liquid level in the shell changes, the upper sections of the adjacent fiber bragg grating liquid level sensor shells are communicated through the air pipe, the air pipe keeps the pressure above the liquid level in the shell of the fiber bragg grating liquid level sensor of each monitoring point equal, the lower sections of the adjacent fiber bragg grating liquid level sensor shells are communicated through the liquid pipe, the liquid pipe enables the liquid level in the shell to rise or fall when the vertical displacement of the fiber bragg grating liquid level sensor of each monitoring point falls or rises, the rectangular cantilever beam generates bending deformation, and the; the automatic liquid level controller is provided with a water supply port and an overflow port, and the liquid level height of the fiber bragg grating liquid level sensor is not changed in the process of settlement or rising.

2. The roadbed settlement monitoring device based on the fiber bragg grating as claimed in claim 1, wherein: and a liquid level observation tube is arranged outside the shell to observe the height change of the liquid level in the shell.

3. The roadbed settlement monitoring device based on the fiber bragg grating as claimed in claim 1, wherein: adjusting screw has set adjusting nut, installs the bubble spirit level on the base.

4. The roadbed settlement monitoring device based on the fiber bragg grating as claimed in claim 1, wherein: the fiber bragg grating sensors are fixed with the rectangular cantilever beams through epoxy glue, and adjacent fiber bragg grating liquid level sensors are connected in series through optical cables to carry out signal transmission.

5. The roadbed settlement monitoring device based on the fiber bragg grating as claimed in claim 1, wherein: the shell is internally filled with water or antifreeze, the cost can be reduced by using the water when the ambient temperature is above 0 ℃, the antifreeze is used in monitoring in alpine regions, and the liquid through pipe is provided with a valve.

Technical Field

The invention relates to the field of embankment settlement monitoring devices, in particular to a roadbed settlement monitoring device based on fiber bragg gratings.

Background

With the rapid development of high-speed railway construction, particularly the increase of national investment in recent years, the high-speed railway construction has entered a new development stage. The high-speed railway has to meet the requirements of safety, reliability and comfort, and to meet the requirements, each railway system has to have high quality and high reliability, wherein the stability and smoothness of railway lines are the most important. Railway lines are composed of structures of different characteristics and properties which cooperate to form a smooth line. The structural objects forming the line have differences in strength, rigidity, deformation, material and the like, which inevitably causes the irregularity of the track. The irregularity of the track is mostly caused by the settlement problem, particularly for the soil subgrade in a special geological section, the settlement problem is more serious, and the settlement (particularly uneven settlement) of the subgrade in the service period of the high-speed railway greatly threatens the comfort and the safety of the high-speed train, thereby being one of the most important technical problems facing all countries in the world.

Disclosure of Invention

Aiming at the problems in the background technology, the invention aims to provide a roadbed settlement monitoring device based on fiber bragg gratings, wherein two fiber bragg grating sensors are arranged on the upper side surface and the lower side surface of a cantilever beam, so that temperature self-compensation can be realized, the influence of temperature change on settlement measurement can be eliminated, and the roadbed settlement monitoring device has the advantages of reduced signal attenuation, strong anti-interference capability, high temperature resistance, corrosion resistance, high sensitivity, easiness in integration and the like; the invention has the characteristics of high monitoring precision, difficult damage, high stability, no need of recalibration and difficult electromagnetic interference in the using process, and reduces wiring.

In order to achieve the purpose, the technical scheme of the invention is realized as follows: a roadbed settlement monitoring device based on fiber bragg gratings comprises at least two fiber bragg grating liquid level sensors arranged on a monitoring surface; the fiber bragg grating liquid level sensor comprises a cylindrical shell, the bottom of the shell is arranged on a base, and the base is connected to a bottom plate arranged on a monitoring surface through a fixing screw rod; a rectangular cantilever beam, a cylindrical floating block and an antifreeze are arranged in the shell; the upper side and the lower side of the rectangular cantilever beam are respectively embedded with a fiber grating sensor, the floating block is suspended in the antifreeze solution, and the floating block is hinged with the free end of the rectangular cantilever beam to ensure that the floating block is not in contact with the shell; the fiber bragg grating liquid level sensors are connected with the optical cable in series in a fusion mode, the optical cable is connected with the fiber bragg grating demodulator, strain of the rectangular cantilever beam is collected through the fiber bragg grating demodulator when the liquid level in the shell changes, the upper sections of the adjacent fiber bragg grating liquid level sensor shells are communicated through the air pipe, the air pipe keeps the pressure above the liquid level in the shell of the fiber bragg grating liquid level sensor of each monitoring point equal, the lower sections of the adjacent fiber bragg grating liquid level sensor shells are communicated through the liquid pipe, the liquid pipe enables the liquid level in the shell to rise or fall when the vertical displacement of the fiber bragg grating liquid level sensor of each monitoring point falls or rises, the rectangular cantilever beam generates bending deformation, and the; the automatic liquid level controller is provided with a water supply port and an overflow port, and the liquid level height of the fiber bragg grating liquid level sensor is not changed in the process of settlement or rising.

In the technical scheme, the liquid level observation tube is arranged outside the shell to observe the height change of the liquid level in the shell.

In the technical scheme, the adjusting screw is provided with the adjusting nut in a matching mode, and the bubble level meter is installed on the base.

In the technical scheme, the fiber grating sensors are fixed with the rectangular cantilever beams through epoxy glue, and the adjacent fiber grating liquid level sensors are connected in series through optical cables to transmit signals.

In the technical scheme, the shell is filled with water or antifreeze, the cost can be reduced by using the water when the ambient temperature is higher than 0 ℃, the antifreeze is used in monitoring in alpine regions, and the liquid through pipe is provided with a valve.

The invention has the beneficial effects that: the invention sets two fiber grating sensors on the upper and lower side surfaces of the cantilever beam, can realize temperature self-compensation, eliminates the influence of temperature change on settlement measurement, and has the advantages of small signal attenuation, strong anti-interference capability, high temperature resistance, corrosion resistance, high sensitivity, easy integration and the like; the invention has the characteristics of high monitoring precision, difficult damage, high stability, no need of recalibration and difficult electromagnetic interference in the using process, and reduces wiring.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principles of the invention.

Fig. 1 is a schematic structural diagram of the system of the present invention. FIG. 2 is a schematic diagram of the sedimentation at each measuring point of the example.

Wherein: the device comprises a fiber bragg grating liquid level sensor 1, a rectangular cantilever beam 2, a fiber bragg grating sensor 3, a floating block 4, a shell 5, a base 6, a valve 7, a liquid through pipe 8, a liquid through pipe 9, an optical cable 10, a fiber bragg grating demodulator 11, an adjusting screw 12, a bottom plate 13, a monitoring surface 14, a fixing screw 15, an adjusting nut 16, a liquid level observation pipe 17, a water supply opening 18, an overflow opening 19, an automatic liquid level controller 20 and an antifreezing solution 21.

Detailed Description

The present invention will be further described with reference to the following examples, which are intended to illustrate only some, but not all, of the embodiments of the present invention. Based on the embodiments of the present invention, other embodiments used by those skilled in the art without any creative effort belong to the protection scope of the present invention.

As shown in fig. 1-2, a roadbed settlement monitoring device based on fiber bragg gratings comprises at least two fiber bragg grating liquid level sensors 1 arranged on a monitoring surface 14; the fiber bragg grating liquid level sensor 1 comprises a cylindrical shell 5, the bottom of the shell 5 is arranged on a base 6, and the base 6 is connected to a bottom plate 13 arranged on a monitoring surface 14 through a fixing screw rod 15; the rectangular cantilever beam 2, the cylindrical floating block 4 and the antifreeze are arranged in the shell 5; the upper side and the lower side of the rectangular cantilever beam 2 are respectively embedded with the fiber bragg grating sensors 3, the floating block 4 is suspended in the antifreeze solution 21, and the floating block 4 is hinged with the free end of the rectangular cantilever beam 2 to ensure that the floating block 4 is not in contact with the shell 5; the fiber bragg grating sensors 3 are connected with the optical cable 10 in series in a fusion mode, the optical cable 10 is connected with the fiber bragg grating demodulator 11, strain of the rectangular cantilever beam 2 is collected through the fiber bragg grating demodulator 11 when the liquid level in the shell 5 changes, the upper sections of the shells 5 of the adjacent fiber bragg grating liquid level sensors 1 are communicated through the air pipes 9, the air pipes 9 keep the pressure above the liquid level in the shells 5 of the fiber bragg grating liquid level sensors 1 of all monitoring points equal, the lower sections of the shells 5 of the adjacent fiber bragg grating liquid level sensors 1 are communicated through the liquid pipes 8, the liquid pipes 8 enable the liquid level in the shells 5 to rise or fall when the fiber bragg grating liquid level sensors 1 of all monitoring points vertically displace and descend or ascend, the rectangular cantilever beam 2 is bent and deformed, and the liquid pipes 8; the automatic liquid level controller 20 is provided with a water supply port 18 and an overflow port 19, and the automatic liquid level controller 20 ensures that the liquid level height of the fiber bragg grating liquid level sensor 1 does not change in the process of sedimentation or rising.