CN115540819A - Differential pressure type fiber grating static level settlement measuring device and monitoring method - Google Patents
Differential pressure type fiber grating static level settlement measuring device and monitoring method Download PDFInfo
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
- G01C5/00—Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels
- G01C5/04—Hydrostatic levelling, i.e. by flexibly interconnected liquid containers at separated points
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
- G01K11/00—Measuring temperature based upon physical or chemical changes not covered by groups G01K3/00, G01K5/00, G01K7/00 or G01K9/00
- G01K11/32—Measuring temperature based upon physical or chemical changes not covered by groups G01K3/00, G01K5/00, G01K7/00 or G01K9/00 using changes in transmittance, scattering or luminescence in optical fibres
- G01K11/3206—Measuring temperature based upon physical or chemical changes not covered by groups G01K3/00, G01K5/00, G01K7/00 or G01K9/00 using changes in transmittance, scattering or luminescence in optical fibres at discrete locations in the fibre, e.g. using Bragg scattering
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L11/00—Measuring steady or quasi-steady pressure of a fluid or a fluent solid material by means not provided for in group G01L7/00 or G01L9/00
- G01L11/02—Measuring steady or quasi-steady pressure of a fluid or a fluent solid material by means not provided for in group G01L7/00 or G01L9/00 by optical means
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L19/00—Details of, or accessories for, apparatus for measuring steady or quasi-steady pressure of a fluent medium insofar as such details or accessories are not special to particular types of pressure gauges
- G01L19/04—Means for compensating for effects of changes of temperature, i.e. other than electric compensation
Abstract
The invention discloses a differential pressure type fiber bragg grating static force leveling settlement measuring device and a monitoring method, relates to the technical field of settlement monitoring, and provides a scheme aiming at the defects that settlement monitoring engineering in the prior art is easy to be influenced by environment and the like, and the scheme comprises the following steps: at least a set of differential fiber grating hydrostatic level appearance, lead to liquid system and hydrostatic level appearance air pressure balance system, every differential fiber grating hydrostatic level settlement appearance all contains leads to the liquid pipe connector, air pressure balance link and fiber signal connection end, differential fiber grating hydrostatic level settlement appearance is through leading to the liquid pipe connector and leading to liquid headtotail, differential fiber grating hydrostatic level settlement appearance passes through air pressure balance link and fiber signal connection end and hydrostatic level appearance air pressure balance headtotail. The device has the advantages that the closed type hydraulic sensor is adopted to measure the pressure change caused by the elevation change of the monitoring point, and the device is vibration-resistant; and the fiber grating hydraulic sensor is adopted, so that the measurement precision is high and the interference is not easy to receive.
Description
Technical Field
The invention relates to the technical field of settlement monitoring, in particular to a differential pressure type fiber bragg grating static force leveling settlement measuring device and a monitoring method.
Background
The settlement of an engineering structure seriously affects the safety and stability of related engineering, so that the measurement and monitoring of the settlement amplitude are extremely important. The settlement monitoring method widely applied at present has some defects, for example, most monitoring sensors adopt electromagnetic signal sensors, so that the monitoring sensors have the defects of unstable signals, easy interference of environmental electromagnetic equipment, long and various leads caused by parallel transmission of the leads, low electromagnetic signal precision and the like. Meanwhile, the existing level gauge adopts a buoyancy type measuring technology, a large-volume water tank needs to be additionally arranged at a test point of each level gauge, real-time monitoring and control cannot be carried out, so that the engineering settlement is difficult to master in real time, and the hidden danger of the overall stability of the engineering is buried.
The fiber grating monitoring and sensing technology has the advantages of convenient series connection mode, good electromagnetic interference resistance, high precision and resolution ratio in monitoring and measuring, signal integrity guarantee through remote transmission and the like, and is applied to the measuring work of the level. However, the existing fiber bragg grating settlement measurement technology still needs to be further improved. The existing fiber bragg grating settlement measurement method is characterized in that fiber bragg grating strain gauges are adhered around a cylindrical rod at equal intervals along the axial direction, then the cylindrical rod provided with the strain gauges is embedded in a slope project or fixed on a building project structure, and the fiber bragg grating cylindrical rod and a monitoring structure generate coordinated deformation, so that the fiber bragg grating strain gauges generate tensile or compressive strain. By combining the strain measurement of the fiber bragg grating with the material mechanics theory and the theoretical mechanics theory, the compression or tension change of the cylindrical rod and the settlement change of the structure can be calculated, and further the displacement change of the monitoring structure generating the coordinated deformation is obtained. However, the method has the major defects that the measuring sedimentation range is fixed and limited, the measuring precision is greatly influenced by the characteristics of the round rod material, and the displacement change data is inaccurate.
In summary, the prior art has the following disadvantages: (1) The measuring principle of the level adopts a buoyancy type measuring technology, and a large-volume water tank needs to be additionally arranged at the measuring point of each level, so that the installation steps and the technical requirements are complicated, and meanwhile, a monitoring system is easily influenced by the environment, such as vibration and the like; (2) The static force level gauge adopts a hydraulic sensor for measurement, the hydraulic sensor adopts an electromagnetic signal measurement module, the measurement precision is low, and interference is easily received; (3) Due to the lack of a temperature compensation technology, the existing settlement level can not adapt to the working in a temperature change environment, so that errors caused by temperature to displacement settlement are difficult to avoid; (4) The existing static level settlement monitoring system cannot be applied to engineering environments with air pressure changes such as wind blowing; (5) The existing level settlement sensor adopts a parallel connection mode, and can not simultaneously measure a plurality of settlement data in a large range in a series mode; (6) In the existing settlement monitoring engineering, a liquid passing system is injected with water, however, the medium of water has the defects of easy evaporation, easy volatilization, easy freezing and the like.
Disclosure of Invention
The invention aims to provide a differential pressure type fiber bragg grating static force level settlement measuring device and a monitoring method, and aims to solve the problems in the prior art.
The invention relates to a differential pressure type fiber grating static force level settlement measuring device, which comprises: at least a set of differential fiber grating hydrostatic level appearance, lead to liquid system and hydrostatic level appearance air pressure balance system, every differential fiber grating hydrostatic level appearance of group includes a plurality of differential fiber grating hydrostatic level settlement appearance, every differential fiber grating hydrostatic level settlement appearance all contains leads to the liquid pipe connector, air pressure balance link and fiber signal connection end, differential fiber grating hydrostatic level settlement appearance is through leading to the liquid pipe connector and leading to liquid headtotail, differential fiber grating hydrostatic level settlement appearance passes through air pressure balance link and fiber signal connection end and hydrostatic level appearance air pressure balance headtotail.
Preferably, the differential pressure type fiber grating static level settlement gauge comprises a static level gauge fixing base, the static level gauge fixing base is positioned at the upper part of the differential pressure type fiber grating static level settlement gauge, a hollow clamping groove is arranged in the middle of the static level gauge fixing base, a liquid-filled hydraulic cavity is arranged at the lower part of the static level gauge fixing base, and the fiber grating hydraulic sensor is arranged at the lower part of the liquid-filled hydraulic cavity and communicated with the liquid-filled hydraulic cavity; a hydraulic cavity exhaust valve is arranged on one side of the static level gauge fixing base, and a liquid pipe connecting port is positioned on one side of the liquid filling hydraulic cavity; the air pressure balance connecting end and the optical fiber signal connecting end are positioned at the lower part of the optical fiber grating hydraulic sensor.
Preferably, lead to the liquid system and include water pipe control flap, liquid filling silicone tube and liquid storage pot, every differential pressure formula fiber grating static level settlement appearance is furnished with a water pipe control flap at least, the logical liquid pipe connector connection on every differential pressure formula fiber grating static level settlement appearance has the liquid filling silicone tube, be equipped with the liquid filling connecting pipe that is used for connecting the liquid filling silicone tube on the liquid filling silicone tube, the liquid storage pot is located the one side that a plurality of differential pressure formula fiber grating static level appearances were kept away from to the liquid filling silicone tube, the one end and the liquid filling silicone tube air-tight connection of liquid storage pot, the liquid storage pot downside is equipped with the liquid storage pot mounting bracket, and the liquid storage pot top is equipped with sealed lid, is equipped with in the liquid storage pot and fills chamber and liquid for balance, fill chamber and balance with the liquid upper surface covering anti-freezing evaporation liquid of preventing.
Preferably, the plurality of differential pressure type fiber grating hydrostatic levels comprise a first hydrostatic level settlement gauge, a second hydrostatic level settlement gauge and a third hydrostatic level settlement gauge;
the first static level settlement gauge is in threaded connection and fixation with the first drill hole and the second drill hole through a hollow clamping groove of the first static level settlement gauge, the set height of the first static level settlement gauge is determined by a height point controlled by a water pipe of the first static level gauge, a liquid filling silicone pipe is connected with a liquid filling pipe of a liquid filling pipe airtight connector of the first static level settlement gauge, a first water pipe control valve is further arranged between the liquid filling pipe connector of the first static level settlement gauge and the first liquid filling connecting pipe, and the liquid filling silicone pipes are in airtight connection through the first liquid filling connecting pipe;
the second static level settlement gauge is in threaded connection and fixation with the third drilling hole and the fourth drilling hole through a hollow clamping groove of the second static level settlement gauge, the set height of the second static level settlement gauge is determined by a water pipe control height point of the second static level gauge, a liquid-filling silicone pipe is connected with a liquid-filling pipe of the second static level settlement gauge in an airtight mode, a second water pipe control valve is further arranged between the liquid-filling pipe connector of the second static level settlement gauge and the second liquid-filling connecting pipe, and the liquid-filling silicone pipes are connected in an airtight mode through the second liquid-filling connecting pipe;
the third static level settlement gauge is fixed through the hollow clamping groove of the third static level settlement gauge, the fifth drilling hole and the sixth drilling hole are in threaded connection, the height set by the third static level settlement gauge is determined by a water pipe control height point of the third static level gauge, a liquid pipe airtight connecting port liquid-filled silicone pipe of the third static level settlement gauge is arranged, a third water pipe control valve is further arranged between the liquid pipe connecting port of the third static level settlement gauge and the third liquid-filled connecting pipe, and the liquid-filled silicone pipe is in airtight connection through the third liquid-filled connecting pipe.
Preferably, the air pressure balance system of the static level comprises an optical fiber grating signal demodulator and an air pressure control interface, the first static level settlement gauge, the second static level settlement gauge and the third static level settlement gauge are respectively in signal connection with an optical fiber grating signal transmission line through respective optical fiber signal connection ends, and the optical fiber grating signal transmission line is in signal connection with the optical fiber grating signal connection interface on the optical fiber grating signal demodulator; the first static level settlement gauge, the second static level settlement gauge and the third static level settlement gauge are respectively connected with a balance air pressure pipe in an airtight mode through respective air pressure balance connecting ends, and the balance air pressure pipe is connected with an air pressure control interface in an airtight mode;
and the fiber grating signal demodulator is provided with a fiber grating signal display interface.
Preferably, the first liquid-filled connecting pipe is a two-way connecting pipe, and the second liquid-filled connecting pipe and the third liquid-filled connecting pipe are three-way connecting pipes.
Preferably, the fiber bragg grating hydraulic sensors are provided with a plurality of fiber bragg grating hydraulic sensors, and each fiber bragg grating hydraulic sensor comprises a pressure measurement fiber bragg grating and a temperature measurement fiber bragg grating.
A static level settlement monitoring method of a differential pressure type fiber bragg grating utilizes a static level settlement measuring device of the differential pressure type fiber bragg grating to monitor;
the method comprises the following steps: s1: installing a group of differential pressure type fiber bragg grating level settlement gauges; s2: installing a liquid passing system; s3: connecting the differential pressure type fiber bragg grating level settlement gauge with a liquid passing system; s4: carrying out settlement monitoring by using a differential pressure type fiber bragg grating level settlement gauge and the like; s5: and collecting and analyzing the data for monitoring the settlement.
Preferably, the step S1 includes that the heights of the first hydrostatic level water pipe control height point, the second hydrostatic level water pipe control height point and the third hydrostatic level water pipe control height point are measured by a horizontal total station, and the first hydrostatic level settlement gauge, the second hydrostatic level settlement gauge and the third hydrostatic level settlement gauge are fixed in the drill hole by passing through respective hollow clamping grooves through bolts;
the step S2 comprises the steps of installing the liquid storage tank on the upper part of the liquid storage tank installation frame, and connecting a liquid filling silicone tube with the bottom of the liquid storage tank;
the step S3 comprises the steps of firstly closing the first water pipe control valve and the second water pipe control valve, opening the third water pipe control valve, then folding the liquid-filled silicone tube until the liquid for filling the cavity and balancing is injected into the liquid storage tank to the lower liquid level, and covering the sealing cover when the liquid for filling the cavity and balancing is injected into the liquid storage tank to the upper liquid level; checking the air tightness of the installed parts, and observing whether liquid seeps out of each joint position;
the step S4 comprises the steps of measuring the water pressure of a monitoring point through a fiber grating hydraulic sensor on the differential pressure type fiber grating level settlement gauge and ensuring the air pressure environment of each differential pressure type fiber grating level settlement gauge to be consistent through an air pressure balance system of the static level gauge;
the step S5 comprises the steps of firstly recording the initial wavelength lambda of the pressure fiber grating in the fiber grating hydraulic sensor 0 And the initial wavelength lambda of the temperature-compensated fiber grating T0 Then recording the wavelength of the pressure fiber grating in the fiber grating hydraulic sensor in real time in the sedimentation process of the differential pressure fiber grating level settlement gaugeLambda and wavelength lambda of temperature fiber grating T The wavelength variation of each position pressure fiber grating and temperature fiber grating is calculated respectively, and the method further comprises the following steps: and calculating the specific numerical value of the settlement change delta h of the differential pressure type fiber bragg grating level settlement gauge.
Preferably, checking the air tightness of the installed part, observing whether liquid seeps out of each joint position comprises opening a water pipe control valve corresponding to each differential pressure type fiber grating level settlement gauge, checking whether bubbles exist in the liquid filling silicone pipe, if the bubbles exist, lifting the liquid filling silicone pipe, stroking forwards and guiding the bubbles to the water pipe control valve corresponding to each differential pressure type fiber grating level settlement gauge to be discharged, marking the liquid level position on the wall body where each fiber grating hydraulic sensor is installed after determining that no bubbles exist in the liquid filling silicone pipe, connecting a first liquid filling connecting pipe, a second liquid filling connecting pipe, a third liquid filling connecting pipe, a first water pipe control valve, a second water pipe control valve and a third water pipe control valve, then opening a hydraulic cavity exhaust valve on the differential pressure type fiber grating level settlement gauge, enabling the liquid filling cavity and balance liquid to flow into the liquid filling hydraulic cavity of each differential pressure type fiber grating level settlement gauge, discharging the bubbles from the hydraulic cavity exhaust valve, and closing the hydraulic cavity exhaust valve after the liquid is continuously discharged.
The differential pressure type fiber bragg grating static force leveling settlement measuring device and the monitoring method have the advantages that a displacement leveling settlement meter adopting a buoyancy principle in the prior art is abandoned, a large-volume water tank does not need to be additionally arranged at a test point, a closed hydraulic sensor is adopted to measure pressure change caused by elevation change of the monitoring point, vibration resistance is realized, the volume is small, and the device is portable;
an electromagnetic signal measuring module used in the traditional method is abandoned, and a fiber grating hydraulic sensor is adopted, so that the measuring precision is high, interference is not easy to receive, and high-frequency real-time monitoring can be realized;
the fiber grating hydraulic sensor comprises a temperature measurement fiber grating which can be used for correcting sensor data drift caused by external temperature change and substantially reducing the influence of the temperature change on a monitoring result;
the air pressure balance system of the hydrostatic level can be applied to the environment with air pressure change, and is not easily influenced by the environment in the monitoring process;
the signal of the fiber bragg grating settlement sensor is in a serial optical signal transmission mode, and a plurality of settlement data in a large range can be measured simultaneously in the serial mode;
the filling cavity and the balancing liquid in the liquid storage tank are covered with a layer of anti-freezing and anti-evaporation liquid, so that the freezing, volatilization and evaporation of water are avoided.
Drawings
FIG. 1 is a schematic structural diagram of a differential pressure type fiber grating static level settlement gauge according to the present invention;
FIG. 2 is a schematic view of a fluid communication system;
FIG. 3 is a schematic diagram of a differential pressure type fiber grating static level settlement measuring device;
FIG. 4 is a schematic diagram of the differential pressure type fiber grating static level settlement measuring device during the monitoring process.
Detailed Description
As shown in fig. 1, the device for measuring sedimentation of static level of differential pressure type fiber grating according to the present invention includes a group of static level of differential pressure type fiber grating, a liquid passing system matching with the static level of differential pressure type fiber grating, an air pressure balance system of the static level, and a data monitoring system for connecting with the fiber grating.
Differential fiber grating hydrostatic level settlement appearance 12 includes hydrostatic level appearance unable adjustment base 11, hydrostatic level appearance unable adjustment base 11 is located differential fiber grating hydrostatic level settlement appearance 12's upper portion, and 11 middle parts of hydrostatic level appearance unable adjustment base are equipped with cavity draw-in groove 13. The two fixing bolts are uniformly distributed inside hollow clamping grooves of the differential pressure type fiber grating static level settlement gauge 12 and are used for fixing the differential pressure type fiber grating static level settlement gauge 12. The liquid-filled hydraulic cavity 19 is arranged at the lower part of the static level fixing base 11, and the fiber grating hydraulic sensor 16 is arranged at the lower part of the liquid-filled hydraulic cavity 19. The fiber grating hydraulic sensor 16 is connected with a liquid-filled hydraulic cavity 19 through a liquid permeation channel. The plurality of fiber grating hydraulic sensors 16 are arranged in series, so that the number of wires of the fiber grating hydraulic sensors 16 and the arrangement protection difficulty can be reduced. The fiber grating hydraulic sensors 16 are connected by adopting the fiber connectors, so that the distance between the measuring points of the sensors can be adjusted according to the specific requirements of actual engineering, and a plurality of settlement data in a large range can be conveniently collected and monitored. Each fiber grating hydraulic sensor 16 comprises a pressure fiber grating and a temperature fiber grating, the fiber grating hydraulic sensor 16 senses water pressure change through an induction film and transmits the water pressure change to the pressure fiber grating, the temperature fiber grating compensates the temperature of the fiber grating hydraulic sensor 16, sensor data drift caused by external temperature change is corrected and is not changed along with the pressure change, and the fiber grating hydraulic sensor can be used for correcting measurement data in different temperature environments and eliminating the influence of the temperature.
One side of the static level gauge fixing base 11 is provided with a hydraulic cavity exhaust valve 14, and a liquid pipe connecting port 15 is positioned on one side of a liquid filling hydraulic cavity 19. When liquid is injected into the differential pressure type fiber bragg grating static level settlement gauge 12 from the subsequent liquid storage tank 27, the anti-freezing and anti-evaporation liquid 29 can be directly injected into the liquid-filled hydraulic cavity 19 through the liquid-communicating pipe connecting port 15 to fill the liquid-filled hydraulic cavity 19, and when the liquid begins to overflow from the exhaust valve 14 of the hydraulic cavity, it can be judged that the liquid in the liquid-filled hydraulic cavity 19 is full, so that the use requirement of the device is met.
The air pressure balance connecting end 17 and the optical fiber signal connecting end 18 are positioned at the lower part of the fiber grating hydraulic sensor 16. Differential fiber grating hydrostatic level settlement gauge 12 leads to liquid union coupling through leading to liquid pipe connector 15 and leads to liquid union coupling, and differential fiber grating hydrostatic level settlement gauge 12 passes through atmospheric pressure balance link 17 and optical signal connection 18 and hydrostatic level atmospheric pressure balance system connection.
The liquid passing system comprises a water pipe control valve, a liquid filling silicone tube 23 and a liquid storage tank 27. The liquid passing system adopts the principle of a liquid communicating vessel during measurement. Each differential pressure type fiber grating static level settlement gauge 12 is at least provided with a water pipe control valve, a liquid pipe connector 15 on each differential pressure type fiber grating static level settlement gauge 12 is connected with a liquid filling silicone tube 23, a liquid filling connecting pipe 23 used for connecting the liquid filling silicone tubes is arranged on each liquid filling silicone tube, the liquid storage tank 27 is located on one side, away from the differential pressure type fiber grating static level gauges 12, of each liquid storage tank 27, one end of each liquid storage tank 27 is connected with the liquid filling silicone tube 23 in an airtight mode, a liquid storage tank mounting frame 210 is arranged on the lower side of each liquid storage tank 27, a sealing cover 26 is arranged at the top of each liquid storage tank 27, liquid 25 for filling cavities and balancing is arranged in each liquid storage tank 27, and freezing-prevention evaporation liquid 29 covers the upper surfaces of the liquid 25 for filling the cavities and balancing.
The group of pressure differential type fiber grating static level instruments comprises a plurality of pressure differential type fiber grating static level settlement instruments. The number of the hydrostatic level sinkers in this embodiment is three, namely a first hydrostatic level sinker 31, a second hydrostatic level sinker 32 and a third hydrostatic level sinker 33.
The first static level settlement gauge 31 is fixedly connected with the first drilling hole 241 and the second drilling hole 242 through a hollow clamping groove of the first static level settlement gauge 31 in a threaded manner, the height of the first static level settlement gauge 31 is determined by a first static level gauge water pipe control height point 281, a liquid filling silicone tube 23 is connected with a liquid through pipe airtight connector of the first static level settlement gauge 31, a first water pipe control valve 211 is further arranged between the liquid through pipe connector of the first static level settlement gauge 31 and the first liquid filling connecting pipe 221, and the liquid filling silicone tube 23 is connected with the first liquid filling connecting pipe 221 in an airtight manner.
The second static level settlement gauge 32 is fixed in threaded connection with the third drilling hole 243 and the fourth drilling hole 244 through a hollow clamping groove of the second static level settlement gauge 32, the height of the second static level settlement gauge 32 is determined by a second static level gauge water pipe control height point 282, a liquid filling silicone tube 23 is connected with a liquid through pipe airtight connector of the second static level settlement gauge 32, a second water pipe control valve 212 is further arranged between the liquid through pipe connector of the second static level settlement gauge 32 and the second liquid filling connecting pipe 222, and the liquid filling silicone tubes 23 are connected in an airtight mode through the second liquid filling connecting pipe 222.
The third static level settlement gauge 33 is fixedly connected with the fifth drilling hole 245 and the sixth drilling hole 246 through a hollow clamping groove of the third static level settlement gauge 33 in a threaded manner, the height of the third static level settlement gauge 33 is determined by a third static level gauge water pipe control height point 283, a liquid filling silicone pipe 23 is connected with a liquid through pipe airtight connector of the third static level settlement gauge 33, a third water pipe control valve 213 is further arranged between the liquid through pipe connector of the third static level settlement gauge 33 and the third liquid filling connecting pipe 223, and the liquid filling silicone pipes 23 are connected with each other in an airtight manner through the third liquid filling connecting pipe 223. The first liquid-filling connection pipe 221 is a two-way connection pipe, and the second liquid-filling connection pipe 222 and the third liquid-filling connection pipe 223 are three-way connection pipes.
The air pressure balance system of the hydrostatic level comprises an optical fiber grating signal demodulator 37 and an air pressure control interface 35, wherein the first hydrostatic level settlement gauge 31, the second hydrostatic level settlement gauge 32 and the third hydrostatic level settlement gauge 33 are respectively in signal connection with an optical fiber grating signal transmission line 36 through respective optical fiber signal connection ends, and the optical fiber grating signal transmission line 36 is in signal connection with an optical fiber grating signal connection interface 39 on the optical fiber grating signal demodulator 37. The first static level settlement gauge 31, the second static level settlement gauge 32 and the third static level settlement gauge 33 are respectively connected with a balance air pressure pipe 34 in an airtight mode through respective air pressure balance connecting ends, and the balance air pressure pipe 34 is connected with an air pressure control interface 35 in an airtight mode. The fiber grating signal demodulator 37 is provided with a fiber grating signal display interface 38.
And monitoring by using the differential pressure type fiber bragg grating static level settlement measuring device.
The differential pressure type high-precision fiber grating static level settlement monitoring method comprises the following steps: s1: installing a group of differential pressure type fiber bragg grating level settlement gauges; s2: installing a liquid flowing system; s3: connecting the differential pressure type fiber bragg grating level settlement gauge with a liquid passing system; s4: carrying out settlement monitoring by using a differential pressure type fiber bragg grating level settlement gauge and the like; s5: and collecting and analyzing the data for monitoring the settlement.
The step S1 includes that the heights of the first hydrostatic level water pipe control height point 281, the second hydrostatic level water pipe control height point 282, and the third hydrostatic level water pipe control height point 283 are measured by a horizontal total station, and the first hydrostatic level settlement gauge 31, the second hydrostatic level settlement gauge 32, and the third hydrostatic level settlement gauge 33 are fixed in the drill hole by passing through respective hollow clamping grooves through bolts.
The step S2 comprises the steps of installing the liquid storage tank 27 on the upper part of the liquid storage tank mounting frame 210 and connecting the liquid filling silicone tube 23 with the bottom of the liquid storage tank 27.
The step S3 includes first closing the first water pipe control valve 211 and the second water pipe control valve 212, opening the third water pipe control valve 213, then folding the liquid-filled silicone tube 23 until the filling cavity and the balancing liquid 25 are filled into the liquid storage tank 27 to the lower liquid level, and covering the sealing cover 26 when the filling cavity and the balancing liquid 25 are filled into the liquid storage tank 27 to the upper liquid level. The lower level is about 10 cm from the bottom of the tank. The upper level is about 10 cm from the top of the tank.
The method also comprises checking the air tightness of the installed parts and observing the liquid seepage at each joint position. Opening the water pipe control valves corresponding to the differential pressure type fiber bragg grating level settlers, checking whether bubbles exist in the liquid filling silicone pipe 23, if so, lifting the liquid filling silicone pipe 23, stroking forward and guiding the bubbles to the water pipe control valves corresponding to the differential pressure type fiber bragg grating level settlers for discharge, marking the liquid level position on the wall body where the fiber bragg grating hydraulic sensors are installed after determining that no bubbles exist in the liquid filling silicone pipe 23, connecting the first liquid filling connecting pipe 221, the second liquid filling connecting pipe 222, the third liquid filling connecting pipe 223, the first water pipe control valve 211, the second water pipe control valve 212 and the third water pipe control valve 213, then opening the exhaust valve of the hydraulic cavity on the differential pressure type fiber bragg grating level settlers, allowing the liquid 25 for filling cavity and balancing to flow into the liquid filling hydraulic cavities of the differential pressure type fiber bragg grating level settlers, discharging the bubbles from the exhaust valve of the hydraulic cavity, and closing the exhaust valve of the hydraulic cavity after the liquid is continuously discharged.
And S4, measuring the water pressure of a monitoring point by a fiber grating hydraulic sensor on the differential pressure type fiber grating level settlement gauge, and ensuring the air pressure environment of each differential pressure type fiber grating level settlement gauge to be consistent by an air pressure balance system of the hydrostatic level gauge.
The step S5 comprises the steps of firstly recording the initial wavelength lambda of the pressure fiber grating in the fiber grating hydraulic sensor 0 And the initial wavelength lambda of the temperature-compensated fiber grating T0 Then recording the wavelength lambda of the pressure fiber grating and the wavelength lambda of the temperature compensation fiber grating in the fiber grating hydraulic sensor in real time in the sedimentation process of the differential pressure fiber grating level settlement gauge T Respectively calculate the pressure light at each positionThe wavelength variation of the fiber grating and the temperature compensation fiber grating.
And obtaining a mathematical relation between the wavelength variation and the sedimentation displacement variation of the pressure fiber bragg grating according to the obtained data, and drawing a calibration curve of the relation between the pressure variation and the sedimentation displacement variation. Referring to the horizontal elevation reference baseline 46 in fig. 4 as a reference, the differential pressure fiber grating level sinker is in an initial position 41 at the horizontal elevation reference baseline 46. The settlement change delta h of the differential pressure type fiber bragg grating level settlement gauge is divided into the following three conditions: when the differential pressure type fiber bragg grating leveling instrument ascends to the ascending position 42, delta h1 is larger than 0; when the differential pressure type fiber bragg grating leveling instrument descends to a descending position 43, delta h2 is less than 0; when the differential pressure fiber grating level settlement gauge is still at the horizontal elevation reference baseline 45 after being changed, Δ h3=0.Δ h4=0 while reservoir 27 is still at the horizontal elevation reference baseline 45 during operation.
And meanwhile, the sensitivities of the stress fiber grating and the temperature fiber grating are recorded, the sensitivity of the wavelength change value of the stress fiber grating is different from that of the temperature fiber grating, the stress fiber grating variation caused by inclination can be obtained, and therefore the influence of temperature factors on measuring settlement is eliminated.
Further comprising: calculating the specific numerical value of the settlement change delta h of the differential pressure type fiber bragg grating level settlement gauge, wherein the delta h is calculated by the following formula:
wherein lambda is the measurement wavelength of the pressure fiber grating in the working process of the differential pressure fiber grating level settlement gauge,
λ 0 the initial wavelength of the pressure fiber grating is calibrated for the differential pressure fiber grating level settlement gauge,
λ T is the measuring wavelength of the temperature fiber grating in the working process of the differential pressure type fiber grating level settlement gauge,
λ T0 the initial wavelength of the medium-temperature fiber grating is calibrated for the differential pressure fiber grating level settlement gauge,
K T is a proportional coefficient of temperature, and is,
and K is a linear coefficient obtained by a calibration test.
Various other modifications and changes may occur to those skilled in the art based on the foregoing teachings and concepts, and all such modifications and changes are intended to be included within the scope of the appended claims.
Claims (10)
1. The utility model provides a differential pressure formula fiber grating static level settlement measuring device which characterized in that includes: the differential fiber grating static level of a plurality of groups, lead to liquid system and static level appearance air pressure balance system, the differential fiber grating static level of every group includes that a plurality of differential fiber grating static level subsides appearance (12), every differential fiber grating static level subsides appearance (12) all contains leads to liquid pipe connector (15), air pressure balance link (17) and fiber signal link (18), differential fiber grating static level subsides appearance (12) through leading to liquid pipe connector (15) and leading to liquid headtotail, differential fiber grating static level subsides appearance (12) and is connected with static level appearance air pressure balance headtotail through air pressure balance link (17) and fiber signal link (18).
2. The differential pressure type fiber grating static level settlement measuring device according to claim 1, wherein the differential pressure type fiber grating static level settlement gauge (12) comprises a static level gauge fixing base (11), the static level gauge fixing base (11) is positioned at the upper part of the differential pressure type fiber grating static level settlement gauge (12), a hollow clamping groove (13) is arranged at the middle part of the static level gauge fixing base (11), a liquid-filled hydraulic cavity (19) is arranged at the lower part of the static level gauge fixing base (11), and the fiber grating hydraulic sensor (16) is arranged at the lower part of the liquid-filled hydraulic cavity (19) and is communicated with the liquid-filled hydraulic cavity (19); a hydraulic cavity exhaust valve (14) is arranged on one side of the static level gauge fixing base (11), and a liquid pipe connecting port (15) is positioned on one side of a liquid filling hydraulic cavity (19); the air pressure balance connecting end (17) and the optical fiber signal connecting end (18) are positioned at the lower part of the optical fiber grating hydraulic sensor (16).
3. The differential pressure type fiber grating static level settlement measuring device according to claim 2, wherein the liquid passing system comprises a water pipe control valve, a liquid filling silicone tube (23) and a liquid storage tank (27), each differential pressure type fiber grating static level settlement meter (12) is at least provided with one water pipe control valve, a liquid passing pipe connector (15) on each differential pressure type fiber grating static level settlement meter (12) is connected with the liquid filling silicone tube (23), a liquid filling connecting pipe (23) for connecting the liquid filling silicone tube is arranged on the liquid filling silicone tube, the liquid storage tank (27) is located on one side, away from the plurality of differential pressure type fiber grating static level meters (12), of the liquid storage tank (27) is in airtight connection with the liquid filling silicone tube (23), a liquid storage tank mounting frame (210) is arranged on the lower side of the liquid storage tank (27), a sealing cover (26) is arranged on the top of the liquid storage tank (27), and a filling cavity and balancing liquid (25) are filled with freezing evaporation prevention liquid (25), and the upper surfaces of the filling cavity and balancing liquid (25) cover the freezing evaporation prevention liquid.
4. The differential pressure fiber grating static level settlement measuring device of claim 3, wherein the plurality of differential pressure fiber grating static level gauges includes a first static level settlement gauge (31), a second static level settlement gauge (32) and a third static level settlement gauge (33);
the first static level settlement gauge (31) is fixedly connected with a first drilling hole (241) and a second drilling hole (242) through a hollow clamping groove of the first static level settlement gauge (31) in a threaded manner, the height of the first static level settlement gauge (31) is determined by a first static level water pipe control height point (281), a liquid filling silicone pipe (23) is connected with a liquid through pipe of the first static level settlement gauge (31) in an airtight manner, a first water pipe control valve (211) is further arranged between the liquid through pipe connecting port of the first static level settlement gauge (31) and a first liquid filling connecting pipe (221), and the liquid filling silicone pipes (23) are connected in an airtight manner through a first liquid filling connecting pipe (221);
the second hydrostatic level settlement gauge (32) is fixedly connected with the third drilling hole (243) and the fourth drilling hole (244) through a hollow clamping groove of the second hydrostatic level settlement gauge (32) in a threaded connection mode, the height of the second hydrostatic level settlement gauge (32) is determined by a water pipe control height point (282) of the second hydrostatic level settlement gauge, a liquid filling silicone pipe (23) is connected with a liquid filling pipe connector of the liquid filling pipe of the second hydrostatic level settlement gauge (32) in an airtight mode, a second water pipe control valve (212) is further arranged between the liquid filling pipe connector of the second hydrostatic level settlement gauge (32) and the second liquid filling connecting pipe (222), and the liquid filling silicone pipes (23) are connected in an airtight mode through the second liquid filling connecting pipe (222);
the third static level settlement gauge (33) is fixedly connected with a fifth drilling hole (245) and a sixth drilling hole (246) through a hollow clamping groove of the third static level settlement gauge (33) in a threaded manner, the height of the third static level settlement gauge (33) is determined by a third static level water pipe control height point (283), a liquid pipe airtight liquid filling silica gel pipe (23) of the third static level settlement gauge (33) is connected with a liquid pipe connecting port, a third water pipe control valve (213) is further arranged between the liquid pipe connecting port of the third static level settlement gauge (33) and the third liquid filling connecting pipe (223), and the liquid filling silica gel pipe (23) is connected with the liquid filling connecting pipe (223) in an airtight manner.
5. The differential pressure type fiber grating static level settlement measuring device according to claim 4, wherein the static level air pressure balance system comprises a fiber grating signal demodulator (37) and an air pressure control interface (35), the first static level settlement gauge (31), the second static level settlement gauge (32) and the third static level settlement gauge (33) are respectively in signal connection with a fiber grating signal transmission line (36) through respective fiber signal connection ends, and the fiber grating signal transmission line (36) is in signal connection with the fiber grating signal connection interface (39) on the fiber grating signal demodulator (37); the first static level settlement gauge (31), the second static level settlement gauge (32) and the third static level settlement gauge (33) are respectively in airtight connection with a balance air pressure pipe (34) through respective air pressure balance connection ends, and the balance air pressure pipe (34) is in airtight connection with an air pressure control interface (35);
the fiber grating signal demodulator (37) is provided with a fiber grating signal display interface (38).
6. The differential pressure type fiber bragg grating static level settlement measuring device of claim 4, wherein the first liquid-filled connecting pipe (221) is a two-way connecting pipe, and the second liquid-filled connecting pipe (222) and the third liquid-filled connecting pipe (223) are three-way connecting pipes.
7. The differential pressure type fiber grating static level settlement measuring device according to claim 2, wherein a plurality of fiber grating hydraulic sensors (16) are provided, and each fiber grating hydraulic sensor (16) comprises a pressure measuring fiber grating and a temperature measuring fiber grating.
8. A method for monitoring the static leveling settlement of a differential fiber grating, which is characterized in that the device for measuring the static leveling settlement of the differential fiber grating according to claims 1-7 is used for monitoring;
the method comprises the following steps: s1: installing a group of differential pressure type fiber bragg grating level settlement gauges; s2: installing a liquid passing system; s3: connecting the differential pressure type fiber bragg grating level settlement gauge with a liquid passing system; s4: carrying out settlement monitoring by using a differential pressure type fiber bragg grating level settlement gauge and the like; s5: and collecting and analyzing the data for monitoring the settlement.
9. The method for monitoring the static level settlement of the differential pressure type fiber bragg gratings according to claim 8, wherein the step S1 comprises that the heights of a first static level water pipe control height point (281), a second static level water pipe control height point (282) and a third static level water pipe control height point (283) are measured by a horizontal total station, and the first static level settlement gauge (31), the second static level settlement gauge (32) and the third static level settlement gauge (33) are fixed in the drill hole through respective hollow clamping grooves by bolts;
the step S2 comprises the steps that the liquid storage tank (27) is arranged at the upper part of the liquid storage tank mounting frame (210), and the liquid filling silicone tube (23) is connected with the bottom of the liquid storage tank (27);
the step S3 comprises the steps that the first water pipe control valve (211) and the second water pipe control valve (212) are closed firstly, the third water pipe control valve (213) is opened, then the liquid-filled silicone tube (23) is folded up firstly until the liquid for filling the cavity and the liquid for balancing (25) are filled into the liquid storage tank (27) to the lower liquid level, and when the liquid for filling the cavity and the liquid for balancing (25) are filled into the liquid storage tank (27) to the upper liquid level, the sealing cover (26) is covered; checking the air tightness of the installed parts, and observing whether liquid seeps out of each joint position;
the step S4 comprises the steps of measuring the water pressure of a monitoring point through a fiber grating hydraulic sensor on the differential pressure type fiber grating level settlement gauge and ensuring the air pressure environment of each differential pressure type fiber grating level settlement gauge to be consistent through an air pressure balance system of the static level gauge;
the step S5 comprises the steps of firstly recording the initial wavelength lambda of the pressure fiber grating in the fiber grating hydraulic sensor 0 And the initial wavelength lambda of the temperature-compensated fiber grating T0 Then recording the wavelength lambda of the pressure fiber grating and the wavelength lambda of the temperature compensation fiber grating in the fiber grating hydraulic sensor in the sedimentation process of the differential pressure fiber grating leveling settlement gauge in real time T The wavelength variation of each position pressure fiber grating and temperature fiber grating is calculated respectively, and the method further comprises the following steps: calculating the specific numerical value of the settlement change delta h of the differential pressure type fiber bragg grating level settlement gauge, wherein the delta h is calculated by the following formula:
wherein, the lambda is the measuring wavelength of the pressure fiber grating in the working process of the pressure differential fiber grating level settlement gauge,
λ 0 the initial wavelength of the pressure fiber grating is calibrated for the differential pressure fiber grating level settlement gauge,
λ T is the measuring wavelength of the temperature fiber grating in the working process of the differential pressure type fiber grating level settlement gauge,
λ T0 the initial wavelength of the medium temperature fiber grating is calibrated for the differential pressure fiber grating level settlement gauge,
K T in order to be the temperature proportionality coefficient,
and K is a linear coefficient obtained by a calibration test.
10. The method for static level settlement monitoring of fiber bragg gratings according to claim 9, wherein the step of checking the airtightness of the installed components and checking whether liquid seeps out from the joints comprises opening the water pipe control valves corresponding to the fiber bragg grating level settlers, checking whether bubbles exist in the liquid filled silicone pipe (23), lifting the liquid filled silicone pipe (23) if bubbles exist, stroking the bubbles forward and guiding the bubbles to the water pipe control valves corresponding to the fiber bragg grating level settlers for removal, marking the liquid level position on the wall where the fiber bragg grating hydraulic sensors are installed after determining that no bubbles exist in the liquid filled silicone pipe (23), connecting the first liquid filled connecting pipe (221), the second liquid filled connecting pipe (222), the third liquid filled connecting pipe (223), the first water pipe control valve (211), the second water pipe control valve (212) and the third water pipe control valve (213), then opening the air exhaust valve (14) of the hydraulic chamber of the fiber bragg grating level settlers, allowing the air filling chamber and the balancing liquid (25) to flow into the hydraulic chamber of each fiber bragg grating level settler, removing the liquid from the hydraulic chamber (14) of the fiber bragg grating level settlers, and closing the air exhaust valve (14) after continuously exhausting the liquid filled chamber (14).
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5877426A (en) * | 1997-06-27 | 1999-03-02 | Cidra Corporation | Bourdon tube pressure gauge with integral optical strain sensors for measuring tension or compressive strain |
| CN101718544A (en) * | 2009-11-25 | 2010-06-02 | 南京基泰土木工程仪器有限公司 | Static level monitoring system |
| CN202144600U (en) * | 2011-06-13 | 2012-02-15 | 北京国网富达科技发展有限责任公司 | Static-level-based system for monitoring settlement of foundation of power transmission line tower |
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2022
- 2022-09-15 CN CN202211124231.4A patent/CN115540819A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5877426A (en) * | 1997-06-27 | 1999-03-02 | Cidra Corporation | Bourdon tube pressure gauge with integral optical strain sensors for measuring tension or compressive strain |
| CN101718544A (en) * | 2009-11-25 | 2010-06-02 | 南京基泰土木工程仪器有限公司 | Static level monitoring system |
| CN202144600U (en) * | 2011-06-13 | 2012-02-15 | 北京国网富达科技发展有限责任公司 | Static-level-based system for monitoring settlement of foundation of power transmission line tower |
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