TW202117294A - Dynamic strain type cable force monitor and monitoring method thereof - Google Patents

Abstract

The present invention relates to a strain type cable force monitor, applied to monitor a cable force from a cable, comprising a filled layer configured on a external surface of the cable and encompassing a part of the cable; a metal housing configured on the filled layer and encompassing a part of the filled layer; a fastener configured outside the metal housing and fastening the filled layer and the metal housing to the cable; and a one-axis strain gauge configured a surface of the metal housing.

Description

Dynamic strain type cable force monitor and its monitoring method

The present invention relates to a monitor and monitoring method for monitoring the cable force, in particular to a strain-type cable force monitor and its monitoring method which mainly measure the axial strain of the cable.

For cable-supported bridges, such as suspension bridges and cable-stayed bridges, a supporting structure composed of cables and multiple bridge towers is used to pull Lifting and bearing the weight of the bridge deck and its load, of which the cable is the main stress structure supporting the bridge; the internal force state of the bridge body is closely related to the cable force distribution of the cable. When the bridge body or the deck board bears Abnormal load or damage is often accompanied by significant changes in the cable force. Therefore, in order to ensure the safety of the cable-supported bridge, it is very common to conduct regular inspections or on-site monitoring of it. As the main force-bearing structure, the cable is measured The cable force is an important item in regular testing or field monitoring.

Figure 1 is a schematic diagram showing the cable support structure of a suspension bridge that is commonly used in cable-supported bridges; taking the suspension bridge as an example, the main cable 13 of the suspension bridge 10 is tensioned and both ends are fixed on the anchor foundation 12, and there are multiple bridge towers. 11 is used to carry the main cable 13, and the cable body of the main cable 13 is densely connected with a plurality of vertical slings 14 to pull up the deck board 15. The weight of the bridge deck board 15 is transmitted to the main cable 13 through the vertical sling 14, Part of the cable force borne by the main cable 13 is transmitted to the pylon foundation 16 through the pylon 11, and the other The sub-section is borne by the anchoring foundation 12. In such a supporting system, the maximum cable force that the main cable 13 can bear determines the maximum load of the entire system to a considerable extent.

For cable force measurement, conventional techniques can be divided into direct measurement and indirect measurement. The more common direct measurement methods include hydraulic jacks, load meters, magnetic flux sensors, and fiber optic strain gauges. In addition to the problem of expensive equipment, the direct measurement method often requires cooperation during the construction phase, and the actual construction process is complex and inflexible. Therefore, in practice, the indirect measurement method is still used for cable force measurement; indirect measurement; The measurement method is mainly based on the micro-vibration method. In contrast, the micro-vibration method, which is an indirect measurement, has been widely used due to its non-structural invasiveness, flexible instrument installation time, simple operation and sufficient accurate results. use.

The micro-vibration method is an indirect method to obtain the cable force. The standard process can be roughly divided into three steps. The first stage is vibration measurement, the second stage is signal analysis and processing, and the third stage is seeking effort. There have been many practical applications and a large number of related studies, which are quite mature cable force measurement methods; however, when the micro-vibration method is used in field monitoring, the instruments used to measure vibration are mainly high-unit-price accelerometers (velocimeters) or accelerometers. (accelerometer), but accelerometer is a precision instrument that needs frequent maintenance and calibration, and may be suitable for short-term monitoring of cable force, but for long-term, dynamic and real-time cable force monitoring, it requires extremely high maintenance costs, which is not practical; Because the accelerometer is expensive, usually too many accelerometers are not deployed and used in the entire monitoring operation, which is not conducive to and cannot be used for multi-point deployment and measurement on the main cable.

Therefore, it is necessary to further develop cheaper cable force measuring instruments and measurement methods to replace expensive instruments such as speedometers and accelerometers for cable force measurement, in order to reduce the high cost of cable force monitoring equipment, as the cost of the instrument is reduced. , Can be deployed at multiple points on the main cable It also implements multi-point measurement, which is conducive to the implementation of long-term cable force monitoring. It can even be further configured to each vertical sling or any cable structure required for cable force monitoring to implement complete cable force monitoring. Monitoring, and can be further expanded to be applied to any cable in any technical field where cable force monitoring needs to be implemented.

For this reason, the applicant, after careful experimentation and research, and with perseverance, finally conceived the "dynamic strain type cable force monitor and its monitoring method" in this case, which can overcome the above shortcomings. The following is a brief description of the present invention.

The present invention proposes the use of a strain-type cable force monitor including an artificial flat structure and a resistive strain gauge to measure the axial strain time series data of the cable, and proposes a corresponding method to calculate the cable force after the cable is stressed. The steps are roughly It is to measure the axial strain time series data, analyze the axial strain time series to obtain the natural vibration frequency of the cable, and then use the equivalent simple beam method or the double vibration frequency method to inversely calculate the cable force; Very clear advantages include: simple structure, easy installation, easy implementation, low instrument cost, can be installed at any position on the cable and not limited to the end of the cable, facilitates multi-point deployment, and facilitates the implementation of long-term cable force monitoring, and so on.

Accordingly, the present invention provides a strain-type cable force monitor, which is applied to measure the cable force borne by the cable, and includes: a filling layer, which is arranged on the outer surface of the cable and wraps a part of the cable; A metal shell is arranged on the filling layer and wraps a part of the filling layer; a fastener is arranged on the outer side of the metal shell and fixes the filling layer and the metal shell on the cable; And a uniaxial strain gauge, which is arranged on the surface of the metal shell.

Preferably, the filling layer further includes a first filling layer and a second filling layer, and is combined with The metal shell jointly forms an artificial flat structure on the outer surface of the cable for setting the uniaxial strain gauge.

Preferably, the filling layer contains acrylic, modified acrylic, polyurethane, basic resin, polyamide resin, epoxy resin, solvent-free epoxy resin, room temperature curing epoxy resin, calcium carbonate, catalyst, additive, auxiliary One of agents, diluents, rubber, and combinations thereof.

The present invention further provides a strain-type cable force monitor, which is applied to measure the cable force borne by a cable, and includes: an artificially flattened structure, which includes a metal shell provided on the outer side of the cable with a flat surface, and an intermediary The filling layer between the cable and the metal shell, and fixing the filling layer and the metal shell on the cable with fasteners to provide the flat surface for the cable; and a uniaxial strain gauge, which is provided On the flat surface of the metal shell.

The present invention further provides a strain-type cable force monitor method, which includes the steps of: arranging a filling layer on the outer surface of the cable, and placing a metal shell on the filling layer; disposing a plurality of strains on the surface of the metal shell Type cable force monitor, and measure the complex strain time series of the cable through the strain type cable force monitor; perform fast Fourier transform on the strain time series to obtain complex fast Fourier spectrum; and measure the fast Fourier spectrum Perform frequency spectrum analysis to find out the complex natural vibration frequency of each of these strain-type cable force monitors in each mode.

Preferably, the strain-type cable force monitor method further includes one of the following steps: pre-processing the original data of the strain time series measured by each of the strain-type cable force monitors , To filter out the noise contained therein; perform fast Fourier transform on the strain time series after filtering processing to obtain complex fast Fourier spectrum; and use equivalent simply supported beam method or double beam method based on these natural vibration frequencies The vibration frequency method inversely calculates the cable endurance Cable force.

10‧‧‧Suspended Bridge

11‧‧‧Tower

12‧‧‧Anchoring Foundation

13‧‧‧Main cable

14‧‧‧Sling

15‧‧‧Bridge Plate

16‧‧‧Tower foundation

200‧‧‧Cable

400‧‧‧Uniaxial strain gauge

402‧‧‧Substrate

404‧‧‧sensing array

406‧‧‧Metal wire

408‧‧‧Terminal

410‧‧‧Output wire

500‧‧‧The strain-type cable force monitor of the present invention

502‧‧‧Metal shell

504‧‧‧The first filling layer

506‧‧‧Second infill layer

508‧‧‧Screw hoop

510‧‧‧Artificial leveling structure

A‧‧‧Location

B‧‧‧Location

C‧‧‧Location

D‧‧‧Location

E‧‧‧Location

F‧‧‧Location

R‧‧‧Installation area

R1‧‧‧First end

R2‧‧‧Second end

L‧‧‧long side

ss‧‧‧Short side

pp‧‧‧Stretched side

s‧‧‧Shrinkage

p‧‧‧Stretching amount

v‧‧‧ Lateral displacement

Step 901‧‧‧Place a filling layer on the outer surface of the target cable and a metal shell on the filling layer

Step 902‧‧‧Deploy multiple strain-type cable force monitors on the metal shell, and measure the strain time series of the target cable through these strain-type cable force monitors

Step 903‧‧‧Pre-process the original data of the strain time series measured by each strain-type cable force monitor to filter out the noise contained in it

Step 904‧‧‧Fast Fourier transform is performed on the strain time series after the filtering process to obtain the fast Fourier spectrum

Step 905‧‧‧Perform spectrum analysis on the fast Fourier spectrum to find out the natural vibration frequency of each strain gauge cable force monitor in each mode

Step 906‧‧‧Using equivalent simply supported beam method or double vibration frequency method to inversely calculate the cable force of the target cable

Figure 1 is a schematic diagram showing the cable support structure of a suspension bridge commonly used in cable-supported bridges;

Figures 2 and 3 are schematic diagrams showing the axial strain of the cable due to lateral vibration displacement;

Figure 4 is a schematic diagram showing the structure of the uniaxial strain gauge used in the present invention;

Figure 5 is a schematic diagram showing the side cross-sectional structure of the strain-type cable force monitor installed on the cable according to the present invention;

Figure 6 is a schematic diagram showing the cross-sectional structure corresponding to the side cross-sectional structure shown in Figure 5 on the MM' section line;

Figure 7 is a schematic diagram showing the cross-sectional structure corresponding to the side cross-sectional structure shown in Figure 5 on the NN' section line;

Figure 8 is a schematic diagram showing the deployment of the strain-type cable force monitor of the present invention applied to suspension bridge cables; and

Figure 9 is a flow chart showing the implementation steps of the strain-type cable force monitoring method of the present invention.

The present invention will be fully understood by the following examples, so that those who are familiar with the art can complete it. However, the implementation of the present invention is not limited by the following examples; the schematics of the present invention are not limited by the following examples. It does not include the limitation of size, size and scale. The size, size and scale of the present invention are not limited by the drawings of the present invention when the present invention is actually implemented. system.

The term "preferred" used herein is non-exclusive, and should be understood as "preferably but not limited to". Any steps described or recorded in any specification or claim can be executed in any order, and are not limited to those described in the claim The scope of the present invention should only be determined by the appended claims and their equivalent solutions, and should not be determined by the examples of implementation examples; when the term "including" and its variations appear in the specification and claims in this article, it is An open term does not have a restrictive meaning and does not exclude other features or steps.

Figures 2 and 3 are schematic diagrams showing the axial strain generated by the cable in response to lateral vibration displacement; in this embodiment, for example, a right-angled three-axis card-type coordinate (Cartesian coordinate) is taken as an example. When the disturbance in the y-axis direction produces a lateral displacement v, the shortened side ss of the cable 200 in the x-axis direction corresponds to a shortened amount s, and the stretched side pp corresponds to a stretched amount p. The amount of shortening s and the amount of tension p produced by the measuring cable 200 in the x-axis direction are calculated by the calculation method of the present invention to obtain the cable force that the cable 200 bears.

Figure 4 is a schematic diagram showing the structure of the uniaxial strain gauge used in the present invention; the strain-type cable force monitor of the present invention preferably includes a uniaxial strain gauge 400, which can be used to measure the target cable parallel to The strain in a single axis direction (strain), that is, the amount of stretching or shortening, is usually expressed in units of length. It is assumed but not limited to the condition of a right-angled three-axis cassette coordinate. The single-axis strain gauge 400 can be set after it is set. Measure the amount of stretch or contraction of the target cable parallel to the x-axis, y-axis, or z-axis in a single axis direction.

The uniaxial strain gauge 400 is preferably, but not limited to, a resistance induction strain gauge. In this embodiment, a resistance induction strain gauge is taken as an example. The uniaxial strain gauge 400 includes a substrate 402, an induction array 404, a terminal 408, and an output wire. 410, the sensing array 404 is a curved, continuous and The metal wires 406 distributed on the substrate 402 are preferably formed on the substrate 402 after being etched from copper metal or copper foil. The square array formed by the sensing array 404 has obvious long sides L. The uniaxial strain gauge 400 is to be assembled on the target cable, and the long side L should be parallel to the direction of the target cable's axis to be measured.

After the uniaxial strain gauge 400 and the base plate 402 are fixed to the target cable, they can deform together with the target cable, and maintain approximately the same or proportional strain with the target cable. When the base plate 402 is deformed, Correspondingly, the deformation of the sensing array 404 is caused, and the long side L of the sensing array 404 is correspondingly elongated or shortened, and the electrical impedance value of the sensing array 404 is enlarged and reduced, so that the sense array 404 converts the strain received into the corresponding electrical impedance change , The sensed electrical impedance change signal is transmitted to the receiving end through the output wire 410, and the cable force of the target cable can be obtained after calculation.

Figure 5 is a schematic diagram showing the side cross-sectional structure of the strain-type cable force monitor proposed by the present invention installed on a cable; Figure 6 is a schematic diagram showing the cross-sectional structure corresponding to the side cross-sectional structure shown in Figure 5 on the MM' section line ; Figure 7 is a schematic diagram showing the cross-sectional structure corresponding to the side section structure shown in Figure 5 on the NN' section line; usually the cable is composed of multiple strands of steel cables, so the shape of the outer surface of the cable is generally irregular In addition, the uneven and complex surface is not a flat surface. It is impossible to directly stick the uniaxial strain gauge on the surface for measurement. An artificial flat structure must be fabricated on the outer surface of the cable in advance, and then the uniaxial must be installed on it. Strain gauge.

The present invention proposes to install a filling layer on the outer surface of the cable. The filling layer may preferably include a single layer structure or two double-layer structures arranged at different positions, and then a metal shell is coated on the outside of the filling layer, and then A uniaxial strain gauge is installed on the surface of the metal shell, and an artificial flat structure is formed on the outer surface of the cable through the filling layer and the metal shell. It is convenient to install the uniaxial strain gauge and transmit the strain of the cable to the uniaxial strain gauge.

First select the installation area R on the cable 200 where the uniaxial strain gauge is to be set. The length of the installation area R is preferably between but not limited to 2 cm to 5 cm, or preferably between but not limited to Between 5 cm and 10 cm, wind a certain thickness of tape on the first end R1 and second end R2 of the installation area R. The thickness of the tape determines the thickness of the first filling layer 504 and the thickness of the tape Preferably, it is between but not limited to 0.1 cm to 0.3 cm, or preferably is between but not limited to 0.3 cm to 0.5 cm, and then a piece of transparent plastic hose is inserted into the installation area R and the tape To form a thin shell-shaped space between the outer surface of the cable 200, the hose and the tape at both ends.

Then inject high-hardness AB glue into the thin shell-shaped space of the round tube. The components of the high-hardness AB glue preferably include acrylic, modified acrylic, polyurethane, basic resin, polyamide resin, epoxy resin, and solvent-free epoxy resin. , Room temperature curing epoxy resin, calcium carbonate, catalyst, additive, auxiliary agent, diluent and one of their combinations, when the high hardness AB glue is solidified, remove the plastic hose and the tape wound at both ends, and the cable 200 The thickness of the outer layer is preferably between but not limited to 0.1 cm to 0.3 cm. The first filling layer 504 has high adhesive strength, acid resistance, alkali resistance, compression resistance, drip resistance, high hardness, high rigidity, It can withstand the temperature difference between -40°C and 130°C, has high electrical impedance and other physical characteristics. It is suitable for cables used outdoors. Because of their high hardness and high rigidity, they can faithfully transmit the strain generated by the cable to the metal shell 502 .

After the first filling layer 504 is set on the cable, a ring of rubber gaskets are respectively arranged as the second filling layer 506 near the first end R1 and the second end R2. The thickness of the second filling layer 506 is better Is slightly smaller than the thickness of the first filling layer 504, and then conforms to the outer shape of the first filling layer 504 and the second filling layer 506, and wraps the outer side of the first filling layer 504 and the second filling layer 506 Cover a layer of metal shell (metal shell) 502, and at the position corresponding to the second filling layer 506 of the first end R1 and the second end R2, use a screw hoop (fastener) 508 to connect the metal shell 502 together with the filling The first filling layer 504, the second filling layer 506, and the cable 200 below are tightly fixed, so that the metal shell 502, the first filling layer 504, the second filling layer 506, and the cable 200 can be fixed together as closely as possible into a whole Structure; The artificial flat structure 510 of the present invention includes a metal shell 502, a first filling layer 504, a second filling layer 506, and a screw hoop 508.

In an embodiment, it is preferable to directly surround the cable 200 at the position between the first end R1 and the second end R2, and the thickness of the coating layer is preferably between but not limited to 0.1 cm to 0.3 cm The rubber gasket in between is used as a filling layer, and a single-layer filling layer replaces the double-layer structure of the first filling layer 504 and the second filling layer 506.

Whether the above-mentioned filling layer is a single-layer filling layer structure or a double-layer filling layer structure, in addition to being able to faithfully transmit the strain generated by the cable 200 to the metal shell 502, it can effectively avoid the possibility of the metal shell 502 being contracted and strained in the axial direction. Frustration. Both ends of the metal shell 502 are fixed with screw hoops 508, and a filling layer is arranged between the metal shell 502 and the cable 200 to avoid fatigue damage.

Finally, multiple uniaxial strain gauges 400 are directly adhered to the metal shell 502. Assuming that the outer shape of the cable 200 is simplified to a cylinder and cylindrical coordinates are used, it is better to use a fixed azimuth angle on the surface of the metal shell 502 For example, a 90° or 180° azimuth angle is used, and multiple uniaxial strain gauges 400 are set. Taking Figure 6 as an example, a 90° azimuth angle is used to install four uniaxial strain gauges 400 on the metal shell 502. The strain-type cable force monitor 500 of the present invention is completed; the strain-type cable force monitor 500 of the present invention can directly measure the axial strain on the surface of the cable 200 by using multiple uniaxial strain gauges 400.

The installation of multiple uniaxial strain gauges 400 on the metal shell 502 should preferably cover the shortened side and the stretched side of the cable 200 so as to accurately measure the strain of the cable 200. When the cable vibrates 200, the metal shell 502 will move in conjunction with the cable 200, causing the surface of the metal shell 502 to generate axial strain due to deflection. The strain time series data is obtained after being sensed by multiple uniaxial strain gauges 400, and output to Receiving end.

Figure 8 is a schematic diagram showing the deployment of the strain gauge cable force monitor of the present invention applied to the suspension bridge cable; because the uniaxial strain gauge has a relatively low instrument cost, the cable can be deployed at multiple points for accurate measurement As for the cable strain under various conditions, take the suspension bridge with the cable support structure as an example. As long as necessary, a large number of uniaxial strain gauges can be deployed on each cable. As shown in Figure 8, each cable of the suspension bridge 800 210 and 220 are equipped with multiple uniaxial strain gauges. In six different positions such as position AF, each position AF adopts a 90° azimuth angle. Four uniaxial strain gauges are installed on the cable through the metal shell. Taking Figure 8 as an example, a total of 24 uniaxial strain gauges are deployed on the two cables 210 and 220 disclosed.

After the strain-type cable force monitor of the present invention is configured on the cable, when the cable is stressed, the strain-type cable force monitor can measure the dynamic of the cable over time in real-time. Strain, and obtain the strain time series data, and transmit it to the receiving end. The receiving end is preferably a desktop computer, notebook computer, or network computing server, for example, but not limited to a desktop computer, a notebook computer, or a network computing server. The strain time series data of cable force monitoring and measurement is further processed by a series of calculations.

Before using the strain time series data to calculate the cable force, it is necessary to perform data pre-processing on the raw data of the received strain time series; the data pre-processing is mainly filtering processing to filter out the noise contained in the original data. In addition, the main components of these noises are from The interference of environmental radio waves usually comes from the communication radio waves of telecommunications and wireless communication equipment. The electromagnetic effect causes a weak induced current signal on the induction array of the uniaxial strain gauge. It is not actually caused by the strain caused by the vibration of the cable. It can be used For example, but not limited to Karman filtering, multiple random subtraction (MRD), linear filtering, or non-linear filtering, these noises are filtered from the original data.

Then, perform frequency spectrum analysis on the strain time series after filtering processing to find the natural vibration frequency of the cable in each mode. According to the modal theory, the free vibration of any elastic body can be regarded as a certain shape. , The vibrations generated by their corresponding frequencies are superimposed. These specific shapes are called fundamental modes; the natural vibration frequency of the cable in each mode can preferably be obtained by using Fast Fourier Transform (FFT) ), calculate the FFT spectrum of the strain time series after filtering, and then perform spectrum identification analysis on the FFT spectrum to identify the natural vibration frequency of the cable contained in the FFT spectrum, and use FFT and spectrum identification analysis to calculate the cable The natural vibration frequency of each strain-type cable force monitor in each mode.

In addition, the equivalent simply supported beam method or the double frequency method is used to inversely calculate the cable force; each strain-type cable force monitor on the cable is presented with the corresponding amplitude value of the natural vibration frequency in each mode. , And then normalized by the amplitude value of the largest amplitude among them, the mode shape ratio of each point and the position on the cable are brought into the mode shape function of the simply supported beam to fit the mode shape curve to calculate the corresponding According to the equivalent simply supported beam method, the middle section of the modal shape function can be almost completely fitted with the modal shape function of the simply supported beam regardless of the actual boundary binding of the cable. Therefore, when After calculating the modal shape function of the cable, it can be inversely calculated according to the modal shape function formula. The modal shape function formula is a definite analytical solution. According to the double frequency method, It is based on the assumption and foundation of the equivalent simply supported beam method. For cables with certain boundary conditions and lengths, after calculating the natural vibration frequencies of any two modes, it can be calculated according to the natural vibration frequencies of any two modes. For cable force, the double vibration frequency method provides an analytical solution for the inverse calculation of cable force with certain boundary conditions and length.

Figure 9 is a flow chart showing the implementation steps of the dynamic strain type cable force monitoring method of the present invention; in summary, the present invention also includes a dynamic strain type cable force monitoring method including the following steps: Step 901: On the outer surface of the target cable A filling layer is set on top, and a metal shell is set on the filling layer; Step 902: Deploy a plurality of strain-type cable force monitors on the metal shell, and measure the strain time of the target cable through these strain-type cable force monitors Sequence; Step 903: Pre-process the original data of the strain time series measured by each strain-type cable force monitor to filter out the noise contained therein; Step 904: Filter the strain For the time series, perform fast Fourier transform to obtain a fast Fourier spectrum; step 905: perform spectrum analysis on the fast Fourier spectrum to find the natural vibration frequency of each strain gauge cable force monitor in each mode; and step 906: Use the equivalent simply supported beam method or the double vibration frequency method to inversely calculate the cable force of the target cable.

In the prior art, when the micro-vibration method is used to obtain the cable force, the sensor used to measure the cable vibration signal is generally a speedometer or an accelerometer, but the present invention also proposes to use a resistive strain gauge to form a strain-type cable force monitor , And then find out the natural vibration frequency of the cable in each mode through FFT spectrum analysis, and then calculate the cable force borne by the cable. The strain gauge has the advantages of small size, light weight, high response to dynamic environment, and signal output The advantages of stability and relatively low instrument price can further reduce the instrument cost of cable force monitoring, and can also be used to replace speed gauges and accelerometers in the micro-vibration method.

The strain-type cable force monitor of the present invention can be widely used but not limited to various cable-supported structures, or applied to cables under tension, such as elevator steel cables, cranes, and other cables. The equipment that pulls up objects and other equipment that uses cables to bear the weight can monitor the cable force. The cable support system refers to a load-bearing structure composed of cables, load-bearing surfaces, and multiple support bases. With the support of the supporting base, the cable pulls up and carries the load surface and the weight of the load, thus forming a support system. Common cable support systems include suspension bridges and cable-stayed bridges.

The above embodiments of the present invention can be arbitrarily combined or replaced with each other, thereby deriving more implementation aspects, but they do not deviate from the scope of protection of the present invention, and further embodiments of the present invention are provided as follows:

Embodiment 1: A strain-type cable force monitor, which is applied to measure the cable force borne by the cable, and includes: a filling layer, which is arranged on the outer surface of the cable and wraps a part of the cable; metal A shell, which is arranged on the filling layer and envelops a part of the filling layer; a fastener is arranged on the outer side of the metal shell, and fixes the filling layer and the metal shell on the cable; and The uniaxial strain gauge is arranged on the surface of the metal shell.

Embodiment 2: The strain-type cable force monitor as described in embodiment 1, wherein the filling layer further comprises a first filling layer and a second filling layer, and is formed on the outer surface of the cable together with the metal shell Manually level the structure for setting the uniaxial strain gauge.

Embodiment 3: The strain-type cable force monitor as described in item 2, wherein the first filling layer is made of AR glue, the second filling layer is made of rubber, and the fastener is in the metal shell The body is arranged at a position corresponding to the second filling layer.

Embodiment 4: The strain-type cable force monitor as described in embodiment 1, wherein the filling layer comprises acrylic, modified acrylic, polyurethane, basic resin, polyamide resin, epoxy resin, solvent-free epoxy resin, One of room temperature curing epoxy resin, calcium carbonate, catalyst, additive, auxiliary agent, diluent, rubber and combination thereof.

Embodiment 5: The strain-type cable force monitor as described in embodiment 1, wherein the length of the filling layer is between 2 cm and 10 cm, and the thickness of the filling layer is between 0.1 cm and 0.5 cm .

Embodiment 6: The strain gauge cable force monitor as described in Embodiment 1, wherein the fastener is a hoop, and the uniaxial strain gauge is a resistance strain gauge.

Embodiment 7: The strain-type cable force monitor as described in Embodiment 1, wherein the uniaxial strain gauge is arranged on the stretched side or the shortened side of the cable, and the uniaxial strain gauge is adjusted according to a fixed azimuth angle. When deployed on the cable, the azimuth angle is 45°, 90° or 180°.

Embodiment 8: A strain-type cable force monitor, which is applied to measure the cable force borne by a cable, and includes: an artificially flat structure, which includes a metal shell provided on the outer side of the cable with a flat surface, and a dielectric The filling layer between the cable and the metal shell, and fixing the filling layer and the metal shell on the cable with fasteners to provide the flat surface for the cable; and a uniaxial strain gauge, which is provided On the flat surface of the metal shell.

Embodiment 9: A strain-type cable force monitor method, which includes the steps of: arranging a filling layer on the outer surface of the cable, and placing a metal shell on the filling layer; disposing a plurality of strains on the surface of the metal shell Type cable force monitor, and measure the complex strain time series of the cable through the strain type cable force monitor; perform fast Fourier transform on the strain time series to obtain complex fast Fourier spectrum; and measure the fast Fourier spectrum Perform spectrum analysis Analyze, find out the complex natural vibration frequency of each of these strain-type cable force monitors in each mode.

Embodiment 10: The strain-type cable force monitor method as described in Embodiment 9, further comprising one of the following steps: For each of the strain-type cable force monitors measured by the strain time series The original data is pre-processed to filter out the noise contained therein; the strain time series after the filtering process are subjected to fast Fourier transformation to obtain the complex fast Fourier spectrum; and based on the natural vibration frequencies, the equivalent simplified Support beam method or double vibration frequency method inversely calculate the cable force borne by the cable.

The various embodiments of the present invention can be combined or replaced arbitrarily to derive more implementation modes, but they do not deviate from the scope of protection of the present invention. The protection scope of the present invention is defined by the scope of the patent application of the present invention. The recorder shall prevail.

400‧‧‧Uniaxial strain gauge

500‧‧‧The strain-type cable force monitor of the present invention

502‧‧‧Metal shell

504‧‧‧The first filling layer

506‧‧‧Second infill layer

508‧‧‧Screw hoop

510‧‧‧Artificial leveling structure

R‧‧‧Installation area

R1‧‧‧First end

R2‧‧‧Second end

Claims (10)

A strain-type cable force monitor, which is used to measure the cable force borne by a cable, and includes: A filling layer, which is arranged on an outer surface of the cable and wraps a part of the cable; A metal shell arranged on the filling layer and wrapping a part of the filling layer; A fastener which is arranged on the outer side of the metal shell and fixes the filling layer and the metal shell on the cable; and A uniaxial strain gauge is arranged on the surface of the metal shell. The strain-type cable force monitor according to claim 1, wherein the filling layer further comprises a first filling layer and a second filling layer, and is formed on the outer surface of the cable together with the metal shell An artificially leveled structure for setting the uniaxial strain gauge. The strain-type cable force monitor according to claim 2, wherein the composition of the first filling layer is an AB glue, the material of the second filling layer is a rubber, and the fastener is in the metal shell The upper system is arranged at a position corresponding to the second filling layer. The strain-type cable force monitor according to claim 1, wherein the filling layer contains an acrylic, One modified acrylic, one polyurethane, one basic resin, one polyamide resin, one epoxy resin, One solvent-free epoxy resin, one room temperature curing epoxy resin, one calcium carbonate, one catalyst, One of an additive, an auxiliary agent, a diluent, a rubber, and a combination thereof. The strain-type cable force monitor according to claim 1, wherein the length of the filling layer is between 2 cm and 10 cm, and the thickness of the filling layer is between 0.1 cm and 0.5 cm. The strain gauge cable force monitor according to claim 1, wherein the fastener is a hoop, and the uniaxial strain gauge is a resistance strain gauge. The strain-type cable force monitor according to claim 1, wherein the uniaxial strain gauge is arranged on a stretched side or a shortened side of the cable, and the uniaxial strain gauge is based on a fixed azimuth angle When the cable is deployed, the azimuth angle is 45°, 90°, or 180°. A strain-type cable force monitor, which is used to measure the cable force borne by a cable, and includes: An artificial flattening structure, which includes a metal shell provided on the outer side of the cable including a flat surface, and a filling layer between the cable and the metal shell, and the filling layer is connected to the cable with a fastener. The metal shell is fixed on the cable to provide the flat surface for the cable; and A uniaxial strain gauge is arranged on the flat surface of the metal shell. A strain-type cable force monitor method, which comprises the steps: A filling layer is arranged on the outer surface of a cable, and a metal shell is arranged on the filling layer; Deploy a plurality of strain-type cable force monitors on the surface of the metal shell, and measure the complex strain time series of the cable through the strain-type cable force monitors; Perform fast Fourier transformation on the strain time series to obtain complex fast Fourier spectra; and Perform spectrum analysis on the fast Fourier spectrum to find out the complex natural vibration frequency of each of the strain-type cable force monitors in each mode. The strain-type cable force monitor method described in claim 9 further includes one of the following steps: Pre-processing the original data of the strain time series measured by each strain type cable force monitor to filter out the noise contained therein; Perform fast Fourier transformation on the strained time series after filtering to obtain complex fast Fourier spectrum; and Based on the natural vibration frequencies, an equivalent simply supported beam method or a double vibration frequency method is used to inversely calculate the cable force borne by the cable.

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