CN116608975A - CFRP sensor-based prestress anchorage structure health monitoring system and method - Google Patents
CFRP sensor-based prestress anchorage structure health monitoring system and method Download PDFInfo
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L1/00—Measuring force or stress, in general
- G01L1/20—Measuring force or stress, in general by measuring variations in ohmic resistance of solid materials or of electrically-conductive fluids; by making use of electrokinetic cells, i.e. liquid-containing cells wherein an electrical potential is produced or varied upon the application of stress
- G01L1/22—Measuring force or stress, in general by measuring variations in ohmic resistance of solid materials or of electrically-conductive fluids; by making use of electrokinetic cells, i.e. liquid-containing cells wherein an electrical potential is produced or varied upon the application of stress using resistance strain gauges
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Abstract
The application discloses a prestress anchorage device structure health monitoring system and method based on a CFRP sensor, wherein the monitoring system comprises a CFRP sensor group, a data acquisition unit and a processor; the CFRP sensor group consists of a plurality of CFRP sensors which are axially arranged on the inner wall of the anchor cylinder, and the length of the CFRP sensors is selected according to the strain at the monitoring point; the data collector collects data of the CFRP sensor and inputs the data into the processor, the processor is internally provided with a damage identification model, and the damage identification model analyzes structural health conditions of monitored anchor points according to strain collected by the CFRP sensor. The system and the method designed by the application utilize the structural damage identification model to carry out real-time and rapid processing on signal data generated by the monitored anchorage system after being stressed, and output structural health analysis results; full-field (time-domain) continuous monitoring of the anchor system can also be achieved.
Description
Technical Field
The application belongs to the technical field of structural health monitoring of bridge cables in civil engineering, and particularly relates to a prestress anchorage structure health monitoring system and method based on a CFRP sensor.
Background
Existing engineering practices have shown that the anchors of large span bridge cables are subjected to alternating loads for long periods of time during service (the strain is typically below the yield strength of the material). Under the action of the cyclic load of long-term service, the anchor structure gradually accumulates damage at the defect points or weak positions in the material, the damage in the material is further increased along with the accumulation of the cyclic times, microcracks are caused, and finally the damage in the structure occurs until sudden fracture and damage occur.
Aiming at the structural health condition of an in-service anchor, the traditional structural health monitoring method is to paste a sensing element on the surface of the anchor, so that the safety performance of the structure is monitored and early-warned, but the monitoring mode has the defects of lack of fatigue resistance and durability of a sensor, incapability of real-time monitoring and the like. The general nondestructive testing method has the defects of complex operation, long testing period, difficulty in realizing full-field (time domain) continuous monitoring and the like.
Disclosure of Invention
In order to solve the defects in the prior art, the application provides a prestress anchorage device structure health monitoring system and method based on a CFRP sensor, and the structure health condition analysis result is output by establishing a structure damage identification model and utilizing the structure damage identification model to carry out real-time and rapid processing on signal data generated by a monitored anchorage device system after being stressed; the CFRP sensor is embedded and mounted on the anchor system, so that full-field (time domain) continuous monitoring of the anchor system can be realized.
In order to achieve the above purpose, the technical scheme adopted by the application is as follows:
a CFRP sensor-based prestress anchor structure health monitoring system, comprising:
the CFRP sensor group is axially arranged on the inner wall of the anchor cylinder, and comprises a plurality of CFRP sensors; selecting the length of the CFRP sensor according to the strain of the CFRP sensor mounting position;
the data acquisition device is in signal connection with the CFRP sensor groups and is used for collecting strain data acquired by each CFRP sensor;
the processor is in signal connection with the data acquisition device; the processor is internally provided with a damage identification model, receives the strain data input by the data acquisition unit, and performs damage identification on the anchor cylinder by using the damage identification model.
Further, the method for constructing the damage recognition model and recognizing the damage comprises the following steps:
constructing a control equation between the strain measured by the CFRP sensor and the strain generated by the anchor structure to be tested, wherein the control equation is expressed as follows:
calculating strain epsilon (x, l) of CFRP sensor at Γ monitoring point according to control equation r,cg ) Γ ；ε(x,l r,mt ) Γ Is the strain of the anchor cylinder at the Γ monitoring point, v is a constant term; ψ is the modulus of elasticity and dimensional parameters of the CFRP sensor, the adhesive; x is the distance between the center point of the CFRP sensor and the edge of the CFRP sensor in the axial direction of the anchor barrel (33); l is CFRP sensor length;
setting a damage determination threshold epsilon mt And strain ε (x, l) of CFRP sensor at Γ -th monitoring point r,cg ) Γ And epsilon mt Comparing, outputting a damage identification result, which is expressed as:
further, the method for selecting the length of the CFRP sensor comprises the following steps:
the strain at each monitoring point on the anchor barrel is expressed as a function of length:
taking L when x=0 as a length value of the CFRP sensor at the Γ monitoring point; wherein,is the strain of the CFRP sensor at the Γ monitoring point after the averaging process.
Further, the CFRP sensor comprises CFRP ribs, copper electrodes and wires are arranged at two ends of the CFRP ribs, and the wires are connected with the data collector.
Further, the CFRP rib in the CFRP sensor is arranged coaxially with the anchor cylinder.
Further, the method for selecting the embedding position of the CFRP sensor comprises the following steps: and setting a plurality of monitoring points along the axial direction on the inner wall of the anchor cylinder, wherein each monitoring point is embedded with a CFRP sensor, and the monitoring point corresponds to the center of the CFRP sensor.
Further, at least one caulking groove is formed in the inner wall of the anchor cylinder along the axial direction, and the CFRP sensor group is installed in the caulking groove.
Further, the data collector and the processor realize the transmission of strain data through the wireless base station.
Further, the processor performs information interaction with the terminal device through the server.
A prestress anchor structure health monitoring method based on a CFRP sensor comprises the following steps:
s1, acquiring strain of an anchor cylinder at each monitoring point in the axial direction by using a CFRP sensor group;
s2, inputting the strain at each monitoring point into a damage identification model, and respectively carrying out damage identification on each monitoring point by the damage identification model and outputting a damage identification result.
The beneficial effects of the application are as follows:
1. compared with other monitoring methods, the CFRP sensor self-durability and corrosion resistance adopted in the method can be integrated with a tested structure into a permanent structure, so that real-time monitoring of an all-time domain is realized.
2. Compared with other monitoring methods, the prestress anchorage structure health monitoring system and method based on the CFRP sensor provided by the application have the advantages that the damage identification model adopted in the method is more accurate and efficient, the service state of the tested structure can be accurately judged, and then the early warning and operation and maintenance of the structure are carried out.
3. Compared with other monitoring methods, the CFRP sensor preparation process, flow and operation method provided by the application are simple, and the CFRP sensor is embedded into the anchor structure, so that the whole anchor system is simple and controllable in structure, low in cost and capable of being produced in batches.
4. The whole set of monitoring technology designed by the application has better feasibility, excellent performance and reliability, and can provide technical support for the CFRP sensor to realize sensing, monitoring, early warning and operation and maintenance in an anchor system of a large-span/ultra-large-span bridge in the future.
5. According to the application, according to the stress distribution characteristics of the anchor cylinder, the length of the CFRP sensor at the corresponding monitoring point is obtained according to the strain at the point to be monitored, so that the point can be accurately acquired and the efficiency of the CFRP sensor can be effectively exerted.
Drawings
FIG. 1 is an interlayer strain analysis chart of an anchor, an adhesive, and a CFRP sensor;
FIG. 2 is a graph of strain transfer coefficients for CFRP sensors at various points along the length;
FIG. 3 is a schematic view of an anchor structure;
FIG. 4 is an anchor strain distribution diagram;
FIG. 5 is a process diagram of a CFRP sensor preparation;
FIG. 6 is a drawing of an anchor grooving process;
fig. 7 is a flow chart of an anchor monitoring system.
In fig. 3: 31. the anchor positioning plate 32, the nut 33, the anchor barrel 34, the adhesive 35 and the CFRP stranded wire;
in fig. 4: 41. an anchor tensioning end 42, an anchor free end 43, a maximum stress (variation) distribution area;
in fig. 5: 51. CFRP ribs, 52, conductive adhesive, 53, copper electrodes, 54, wires, 55 and welding spots;
in fig. 6: 61. caulking grooves 62 and wire guiding holes;
in fig. 7: 71. an anchor system, 72, CFRP sensors, 73, and a through jack.
Detailed Description
In order to make the objects, technical solutions and advantages of the present application clear, the following detailed description will be made with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the application.
A CFRP sensor-based prestress anchor structure health monitoring system and method, comprising:
1. CFRP sensor group
Composition of CFRP sensor group: at least one CFRP sensor group including a plurality of CFRP sensors is provided in the axial direction on the inner wall of the anchor cylinder 33. The CFRP sensor structure used in the present application mainly includes CFRP ribs 51, copper electrodes 53 and wires 54 as shown in fig. 5. The preparation method of the CFRP sensor comprises the following steps: cutting the sections at the two ends of the CFRP rib 51 in order, polishing the sections with sand paper to be flat, and then removing section scraps with alcohol. And (3) adhering a copper electrode 53 to the end section of the rib material 51 by using a conductive adhesive 52, and then welding a lead 54 on the copper electrode 53 by using soldering tin to finish the preparation of the CFRP sensor. Curing for 24 hours after applying uniform pressure on the end of the CFRP sensor, and curing the conductive adhesive 52. And finally, uniformly coating epoxy glue 13 on two ends of the CFRP sensor, and forming better electrode protection after curing is finished.
Mounting a CFRP sensor group: referring to fig. 6, a caulking groove 61 for CFRP sensor group installation is formed in the inner wall of the anchor cylinder 33 in the axial direction, and a wire guide hole 62 is formed near the anchor positioning plate 31. The CFRP sensor group is installed in the caulking groove 61. More specifically, as shown in connection with fig. 7, the CFRP sensor in the CFRP sensor group is fitted in the caulking groove 61 and fixed by epoxy resin. The wires 54 of each CFRP sensor are led out of the wire lead holes 62 to connect with the data collector.
Selecting the embedding position of the CFRP sensor: a plurality of monitoring points are axially set on the inner wall of the anchor barrel 33, each monitoring point is provided with a CFRP sensor, and the center of each CFRP sensor corresponds to the monitoring point, so that each CFRP sensor in the CFRP sensor group is embedded in the embedded position of the inner wall of the anchor barrel 33.
And (3) selecting the length of the CFRP sensor: in the present application, the length of the CFRP sensor is selected according to the strain distribution on the anchor barrel 33, i.e., the length of the CFRP sensor at each monitoring point is determined according to the strain at that monitoring point. While the strain at the monitoring point and the length of the CFRP sensor are expressed specifically as: according to a real control equation between the strain measured by the CFRP sensor and the strain generated by the structure of the anchor to be measured, and according to the strain distribution state of the anchor to be monitored after finite element analysis, a strain transmission efficiency coefficient phi (x) is defined based on the theory of distributed sensing to obtain the effective length and embedding position interval of the CFRP sensor.
The average processing is carried out to obtain the average strain transfer efficiency coefficient of the CFRP sensor:
when x=0, namely the middle of the CFRP sensor, the strain transfer coefficient is the largest, and the following are:
2. data acquisition device
The data collector is connected with the CFRP sensors and collects strain data of the anchor barrel 33 collected by each CFRP sensor in the CFRP sensor group at the corresponding monitoring point. The data collector in this embodiment is a strain gauge.
3. Processor and method for controlling the same
The processor receives the strain data transmitted by the data acquisition unit, and a damage identification model is built in the processor; the damage identification model identifies damage to each monitoring point on the anchor barrel 33 based on strain data at each monitoring point. The specific process of constructing the damage recognition model is as follows:
and step 1, establishing a damage identification model aiming at material parameters of the CFRP sensing structure and the anchor.
The force resistance effect of the CFRP rib is achieved by establishing a mathematical physical relationship between the resistance change rate and the strain of the CFRP rib under the mutual coupling action of a static field (a strain field) and an electric field.
(1) At the mechanical level, the strain energy density function of CFRP sensor:
wherein ,σij Is the stress tensor; epsilon ij Is the strain tensor; subscripts i, j are labels on the x, y axes in the Cartesian coordinate system, respectively. Namely:
wherein sigma and epsilon are positive strain and positive strain respectively; τ, γ are shear strain and shear strain, respectively; x, y, z are the 3 directions of the coordinate axis, respectively.
Since the CFRP sensor is a sensor having a longitudinal dimension larger than a lateral dimension, it can be simplified to a plane strain problem, and the above formula (5) can be simplified to:
meanwhile, from the Hooke's law it is known that:
wherein E is the elastic modulus; mu is poisson's ratio.
According to the law of composite materials:
E＝E f V f +E m V m (8)
the elastic strain energy density is:
at this time, the CFRP sensor total strain energy is:
wherein ,Ef ,V f CFRP elastic modulus and volume fraction, respectively; e (E) m ,V m Is the elastic modulus and volume fraction of the epoxy resin matrix.
(2) At the electrical level (CFRP conductive microcosmic mechanism is similar to metal material, obeys ohm's law, and the charge distribution in CFRP material has continuity, according to which the control equation between field strength and resistance in electrostatic field is deduced from energy angle), the total potential energy function of CFRP sensor:
wherein ,ρq Is the bulk charge density;is an electric potential.
From the Maxwell distribution equation, the conductivity of the CFRP sensor is:
wherein n is an electronic serial number; m is electron mass; q is the charge amount; lambda is the mean free path; v is the average rate.
Practical experience of engineering monitoring shows that in the service environment of practical engineering, the influence of temperature effect must be considered, so that according to the electric conduction quantum theory, the electrical property of the CFRP sensor is also related to the fermi level density. Namely:
then formula (13) is rewritten as:
further, the bulk charge density is:
wherein ,εF Is fermi energy; lambda' is the mean free path corresponding to electron wave scattering.
At this time, the total potential energy of the CFRP sensor is:
by integrating the potential energy functions of the CFRP sensor on the mechanical and electrical levels, the total potential energy of the CFRP sensor in the passive electrostatic field can be obtained as follows:
in the passive electrostatic field, the total potential energy follows Thomson's law, so according to the variational principle, the above formula (17)
δU Z =0, then a control equation for the conductivity C and strain epsilon of the CFRP sensor can be obtained:
wherein B, eta and zeta are all constant coefficients of the material.
Meanwhile, according to ohm's law, the resistance value R and the resistivity ρ of the CFRP sensor satisfy:
at the same time, CFRP sensor axial strain epsilon x And the rate of change of resistance DeltaR/R 0 The method meets the following conditions:
wherein A is the cross-sectional area of the CFRP sensor; l is the length of the CFRP sensor; ΔR is the resistance variation of the CFRP sensor; r is R 0 Initial resistance of the CFRP sensor; k is the sensitivity of the CFRP sensor.
Engineering practice shows that the damage of the anchorage is basically axial tensile damage, so that the CFRP sensor is assumed to generate axial strain epsilon only x Then equation (18) may omit ε y ,γ xy The following steps are:
to sum up, the conductivity C and the axial strain epsilon of the CFRP sensor can be obtained x Rate of change of resistance Δr/R 0 Is a control equation of (2).
(3) The bonding between the CFRP sensor and the anchor system is a precondition for ensuring the cooperative work of the CFRP sensor and the anchor system, and is also a key point for ensuring the CFRP sensor to accurately detect the stress and the strain of the anchor structure. I.e. the proportional relation between the strain of the CFRP sensor and the true strain of the anchor. To explore this problem, several assumptions are made as follows:
(1) the CFRP sensor, the adhesive and the anchorage structure are all regarded as ideal materials, and no plastic deformation exists in the loading process;
(2) the mechanical properties of the 3 materials of the CFRP sensor, the adhesive and the anchorage structure are basically the same;
(3) the CFRP sensor, the adhesive and the layers of the anchor structure are not displaced relatively, and the interface is tightly combined without falling off;
(4) the strain generated by deformation of the CFRP sensor and the anchor structure is transmitted by the middle adhesive layer along the axial direction, namely the adhesive layer plays a role in strain transmission.
Referring to fig. 1 for a strain transfer relationship, mt is an anchor cylinder; nj is a binder; cg is CFRP sensor; l (L) r Is the radius of the concentric circles of each layer.
Taking a micro-element section in CFRP sensor bonding as analysis, and axially meeting balance conditions under a static state:
for the adhesive layer between the CFRP sensor and the anchor cylinder, the axial force and static force balance is as follows:
for the monitored structural anchor barrel, the analysis of the micro-element section is carried out, namely:
because the monitored structural anchor cylinder is not subjected to shearing force, the following steps are provided:
and (3) solving to obtain:
substituting equation (26) into equation (24) includes:
substituting the above formulas (22), (23) into formula (27) includes:
according to Hooke's law, formula (28) above may be rewritten as:
wherein ,Ecg ,E nj Elastic moduli of the CFRP sensor and the adhesive are respectively set; epsilon cg ,ε nj Axial strain of the CFRP sensor and the adhesive, respectively.
According to the assumption, the anchor, the adhesive and the CFRP sensor are deformed cooperatively, and then the following steps are provided:
in view of the difference in the modulus of elasticity between CFRP sensors and adhesives, there are:
according to formulas (30), (31), formula (29) is simplified to:
similarly, formula (23) is:
according to the above assumption, the CFRP sensor is deformed only in the axial direction, and ignoring the influence of poisson effect, there are:
according to the formulas (30), (31), the above formula (34) can be simplified as:
because of shear hysteresis effect, the strain of the anchorage device is transmitted to the CFRP sensor through the adhesive, the dislocation displacement between layers and the shear strain can be established to be corresponding, and the shear strain can be obtained through the relative displacement of the upper edge and the lower edge of the adhesive layer:
similarly, the anchor to be tested has:
wherein u is displacement; gamma is the interlaminar shear strain.
Deriving the formulae (36), (37) and according to Hooke's law:
wherein G is the shear modulus. Substituting shear strain, and for l r Taking integral:
defining a coefficient:
then formula (39) is rewritten as:
the differential control equation of the strain measured by the CFRP sensor and the strain generated by the measured anchor structure is adopted. The general solution is as follows:
ε cg (x,l r,cg )＝a 1 sinv(Ψx)+a 2 cosv(Ψx)+ε(x,l r,mt ) (42)
wherein ,a1 ,a 2 Constant terms determined by boundary conditions respectively; v is a constant term; ψ is the modulus of elasticity and dimensional parameters of the CFRP sensor, the adhesive; x is the distance between the center point of the CFRP sensor and the edge of the sensor; l is CFRP sensor length.
Considering that the contact surfaces of the two end surfaces of the CFRP sensor and the middle layer are free end surfaces, the two end surfaces can ignore strain transmission, and the boundary conditions are as follows:
the midpoint of the CFRP sensor pasting part has no shear strain, and the structure is symmetrical, then:
the true control equation between the strain measured by the CFRP sensor and the strain produced by the measured anchor structure is:
from the control equation above, the following damage identification can be made, namely:
wherein Γ is the CFRP sensor number, and Γ is taken as the number of the CFRP sensor 1 ～Γ n 。
4. Terminal
And the terminal receives the processing result of the processor, and performs overall intelligent monitoring of the anchor structure at the terminal according to the outputted damage identification result, so that corresponding engineering measures are adopted to maintain the later-stage service of the engineering structure.
In order to verify the monitoring effect of the system designed by the application, as shown in fig. 7, the application tests the system, and the structure of the anchorage device is shown in fig. 3, which comprises the following steps: the anchor positioning plate 31, the nut 32, the anchor barrel 33, the adhesive 34 and the CFRP stranded wires 35, wherein one end of the anchor barrel 33 is connected with the anchor positioning plate 31, the other end is a free end, a hole which is gradually reduced from the fixed end to the free end is formed in the anchor barrel 33, the CFRP stranded wires 35 are arranged in the hole, and the CFRP stranded wires 35 and the inner wall of the anchor barrel 33 are filled with the adhesive 34; the outer wall surface of the anchor cylinder 33 is also provided with a nut 32.
Referring to fig. 7, the wires 54 of the CFRP sensor 72 are led out of the wire guide holes 62 and connected to a signal receiver for debugging, and then the anchor 71 system is tensioned by using the penetrating jack 73, and data are recorded in real time. And substituting the read data into an analysis model to perform damage identification. The damage identification result output by the system is compared with the damage result actually appearing on the anchor 71, so that the whole set of monitoring technology is verified to have good feasibility, excellent performance and reliability.
Table 1 below shows the parameters of the materials and equipment used in the present monitoring system.
Table 1 materials and apparatus for monitoring systems
In this embodiment, the selection manner about the monitoring point is:
the strain transfer efficiency coefficient of the CFRP sensor is shown in fig. 2. According to the stress distribution profile of the anchor as shown in fig. 4 after numerical simulation, there is a maximum strain distribution area 43 between the anchor tensioning end 41 and the anchor free end 42. In the embodiment, a plurality of monitoring points are arranged on the inner wall of the anchor cylinder 33 from the free end to the stretching end of the anchor cylinder at equal intervals along the axial direction, and then the center point of the CFRP sensor is stuck to a plurality of larger points sigma (epsilon) in the stress cloth area according to the formula (46) max Where it is located.
In summary, mechanical and electrical analysis is performed on a sensor prepared from CFRP materials, a differential control equation of the strain measured by the CFRP sensor and the strain generated by the stress of the structure of the anchor to be tested when the CFRP sensor, the binder and the anchor to be monitored 33 work cooperatively is established, and then a structure damage identification model is established;
determining the length and embedding position of the CFRP sensor in a distributed sensing mode according to the strain transfer efficiency coefficient of the CFRP sensor and the strain distribution area of the monitored anchor; processing a caulking groove in the optimally designed anchorage device along the axial direction for embedding the CFRP sensor; substituting signal data generated by the monitored anchorage system after being stressed into a damage identification model, and analyzing the health condition of the corresponding structure so as to take corresponding engineering measures.
The above embodiments are only for illustrating the design concept and features of the present application, and are intended to enable those skilled in the art to understand the contents of the present application and implement the same. The scope of the present application is not limited to the above embodiments, and therefore, all equivalent changes or modifications according to the theory, technique and method disclosed in the present application are within the scope of the present application.
Claims (10)
1. A CFRP sensor-based prestress anchorage structure health monitoring system, comprising:
the CFRP sensor group is axially arranged on the inner wall of the anchor cylinder (33), and comprises a plurality of CFRP sensors; selecting the length of the CFRP sensor according to the strain of the CFRP sensor mounting position;
the data acquisition device is in signal connection with the CFRP sensor groups and is used for collecting strain data acquired by each CFRP sensor;
the processor is in signal connection with the data acquisition device; the processor is internally provided with a damage identification model, receives the strain data input by the data acquisition unit, and performs damage identification on the anchor cylinder (33) by using the damage identification model.
2. The CFRP sensor-based prestress anchorage structure health monitoring system of claim 1, wherein the damage identification model is constructed and the damage identification method comprises the following steps:
constructing a control equation between the strain measured by the CFRP sensor and the strain generated by the anchor structure to be tested, wherein the control equation is expressed as follows:
calculating strain epsilon (x, l) of CFRP sensor at Γ monitoring point according to control equation r,cg ) Γ ；ε(x,l r,mt ) Γ Is the strain of the anchor cylinder at the Γ monitoring point, v is a constant term; ψ is the modulus of elasticity and dimensional parameters of the CFRP sensor, the adhesive; x is the distance between the center point of the CFRP sensor and the edge of the CFRP sensor in the axial direction of the anchor barrel (33); l is CFRP sensor length;
setting a damage determination threshold epsilon mt And strain ε (x, l) of CFRP sensor at Γ -th monitoring point r,cg ) Γ And epsilon mt Comparing, outputting a damage identification result, which is expressed as:
3. the CFRP sensor-based prestress anchorage structure health monitoring system of claim 2, wherein the CFRP sensor length selecting method is as follows:
the strain at each monitoring point on the anchor barrel (33) is expressed as a function of length:
taking L when x=0 as a length value of the CFRP sensor at the Γ monitoring point; wherein,is the strain of the CFRP sensor at the Γ monitoring point after the averaging process.
4. A CFRP sensor-based prestress anchorage structure health monitoring system according to claim 3, wherein the CFRP sensor comprises CFRP ribs (51), copper electrodes (53) and wires (54) are arranged at two ends of the CFRP ribs (51), and the wires (54) are connected with a data collector.
5. The CFRP sensor-based prestress anchorage structure health monitoring system of claim 4 wherein CFRP ribs (51) in the CFRP sensor are coaxially arranged with anchor cylinders (33).
6. The CFRP sensor-based prestress anchorage structure health monitoring system of claim 5, wherein the CFRP sensor embedding position selecting method is as follows: a plurality of monitoring points are axially set on the inner wall of the anchor barrel (33), each monitoring point is embedded with a CFRP sensor, and the monitoring points correspond to the centers of the CFRP sensors.
7. The prestress anchor structure health monitoring system based on a CFRP sensor according to claim 6, wherein at least one caulking groove (61) is formed in the inner wall of the anchor cylinder (33) along the axial direction, and the CFRP sensor group is installed in the caulking groove (61).
8. The CFRP sensor-based prestress anchorage structure health monitoring system of claim 6, wherein strain data is transmitted between the data collector and the processor through a wireless base station.
9. The CFRP sensor-based prestress anchorage structure health monitoring system of claim 6, wherein the processor performs information interaction with the terminal equipment through a server.
10. The prestress anchorage structure health monitoring method based on the CFRP sensor is characterized by comprising the following steps of:
s1, acquiring strain of an anchor cylinder (33) at each monitoring point in the axial direction by using a CFRP sensor group;
s2, inputting the strain at each monitoring point into a damage identification model, and respectively carrying out damage identification on each monitoring point by the damage identification model and outputting a damage identification result.
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