A method and system for monitoring the full-length axial and bending deformation of an anchor rod

Abstract

The application relates to a method and system for monitoring axial and bending deformation of a full-length anchor rod, comprising the following steps: obtaining strain data of each optical fiber sensing unit; obtaining axial strain values of each monitoring point in the length direction of the anchor rod based on the strain data of each optical fiber sensing unit; and obtaining the cross-section bending degree of each optical fiber sensing unit at each monitoring point based on the strain data of each optical fiber sensing unit and the central angle between adjacent optical fiber sensing units. The method can effectively separate the composite strain measured by the optical fiber, which is the superposition of axial and bending, into independent axial strain component and bending strain component, capture the stress concentration phenomenon and deformation gradient change of the anchor rod at the joint intersection position, and truly and comprehensively restore the actual stress and deformation characteristics of the anchor rod.

Description

Technical Field

[0001] This application relates to the field of geotechnical engineering monitoring technology, and in particular to a method and system for monitoring the axial and bending deformation of anchor bolts along their entire length. Background Technology

[0002] Anchor bolts, as important support structures in geotechnical engineering, are widely used in slope reinforcement, tunnel support, foundation pit support, mining engineering, and other fields. Jointed rock masses, as typical discontinuous media, have numerous joints and bedding planes, leading to complex stress states for anchor bolts. For example, in rock masses with highly developed bedding or joints, when the layered rock mass slides or tends to slide along structural planes, the rock mass exerts strong lateral constraints on the anchor bolts. In this case, the anchor bolts at the intersections with joint planes are subjected to not only axial tensile forces but also shear forces. This combined stress state often makes the joint intersections of anchor bolts stress concentration areas, with drastic changes in deformation gradients and the potential for abrupt changes in local strain.

[0003] Distributed fiber optic sensing technology, with its advantages of anti-electromagnetic interference, corrosion resistance, and small size, has been gradually applied to the field of anchor bolt strain monitoring. However, existing applications still have obvious limitations. Its monitoring focus is mainly on axial strain, and its ability to monitor the bending deformation of anchor bolts under complex stress conditions is insufficient. Even if some schemes adopt a three-slot arrangement to try to reflect the three-dimensional stress state of the anchor bolt, the lack of an effective decoupling algorithm makes it impossible to separate the composite strain of axial and bending measured by the fiber optic cable into independent axial strain components and bending strain components. This makes it difficult to accurately capture the true stress and deformation characteristics of anchor bolts in jointed rock masses. Summary of the Invention

[0004] This application provides a method and system for monitoring the axial and bending deformation of anchor bolts along their entire length, in order to solve the problem in related technologies that there is a lack of effective decoupling algorithms, making it impossible to separate the composite strain of axial and bending measured by optical fibers into independent axial strain components and bending strain components, thus making it difficult to accurately capture the true stress and deformation characteristics of anchor bolts in jointed rock masses.

[0005] Firstly, a method for monitoring the axial and bending deformation of an anchor bolt along its entire length is provided, including the following steps: Strain data of each fiber optic sensing unit is acquired. Each fiber optic sensing unit is arranged along the axial direction of the anchor rod and distributed circumferentially on the cross section of the anchor rod. The strain data consists of the strain values ​​of each monitoring point along the length direction of the anchor rod detected by the fiber optic sensing unit. Based on the strain data from each fiber optic sensing unit, the axial strain value at each monitoring point along the length of the anchor bolt is obtained. Based on the strain data of each fiber optic sensing unit and the central angle between adjacent fiber optic sensing units, the degree of cross-sectional bending of each fiber optic sensing unit at each monitoring point is obtained.

[0006] In some embodiments, based on the strain data from each fiber optic sensing unit, the axial strain value at each monitoring point along the length of the anchor bolt is obtained, including: The strain data from each fiber optic sensing unit are arithmetically averaged to obtain the axial strain value at each monitoring point along the length of the anchor bolt.

[0007] In some embodiments, the degree of cross-sectional bending of each fiber optic sensing unit at each monitoring point is obtained based on the strain data of each fiber optic sensing unit and the central angle between adjacent fiber optic sensing units, including: The strain data difference between adjacent fiber optic sensing units is calculated and squared respectively. Then, the multiple squared values ​​are summed, the summation result is divided by a preset coefficient, and finally the square root of the quotient is taken to obtain the degree of cross-sectional bending of each fiber optic sensing unit at each monitoring point. The preset coefficient is a constant determined by the central angle between adjacent fiber optic sensing units.

[0008] In some embodiments, after acquiring the strain data of each fiber optic sensing unit, the method further includes: The strain data is preprocessed.

[0009] In some embodiments, the strain data is preprocessed, including: Each monitoring point is checked sequentially along the anchor bolt axis to identify missing data or abnormal values ​​exceeding the preset threshold in the strain data. These are marked as data points to be repaired, and the location coordinates and corresponding strain values ​​of the valid data points are extracted. Based on the location coordinates and strain values ​​of valid data points, a continuous distribution function between strain values ​​and location coordinates is constructed using a curve fitting method. The strain value at the location of the data point to be repaired is predicted and filled using the constructed functional relationship.

[0010] In some embodiments, the curve fitting method is a polynomial fitting method; The fitting coefficients of polynomials of each order are calculated using the least squares method, and the corresponding mean square error is also calculated. The polynomial order and its fitting coefficients corresponding to the minimum mean square error are selected as the optimal fitting model.

[0011] In some embodiments, the steps of obtaining the axial strain value and obtaining the degree of cross-sectional bending are performed based on the preprocessed strain data.

[0012] Secondly, a system for monitoring the axial and bending deformation of an anchor bolt along its entire length is provided, including: The data acquisition module is used to acquire strain data from each fiber optic sensing unit. The axial strain calculation module is used to obtain the axial strain value of each monitoring point along the length of the anchor bolt based on the strain data of each fiber optic sensing unit. The cross-sectional bending degree calculation module is used to obtain the cross-sectional bending degree of each fiber optic sensing unit at each monitoring point based on the strain data of each fiber optic sensing unit and the central angle between adjacent fiber optic sensing units.

[0013] Thirdly, an anchor bolt axial and bending deformation monitoring device is provided. The device includes a processor, a memory, and a computer program stored in the memory and executable by the processor. When the computer program is executed by the processor, it implements the steps of the anchor bolt axial and bending deformation monitoring method.

[0014] Fourthly, a computer-readable storage medium is provided, on which an anchor bolt axial and bending deformation monitoring program is stored, wherein when the anchor bolt axial and bending deformation monitoring program is executed by a processor, the steps of the anchor bolt axial and bending deformation monitoring method are implemented.

[0015] This application provides a method and system for monitoring the axial and bending deformation of an anchor bolt along its entire length. For each monitoring point, the axial strain value is obtained by taking the arithmetic mean of at least three strain values. This arithmetic mean of at least three strain values ​​automatically eliminates the influence of bending deformation on strain measurement, effectively offsetting the influence of common-mode temperature strain or complex signal separation processing, and directly obtaining a pure axial strain data sequence. The degree of bending of the cross-section is calculated based on at least three local bending strain values ​​and angles, comprehensively reflecting the degree of bending of the anchor bolt under complex stress conditions. Considering that anchor bolts in jointed rock environments often bear combined axial tensile and shear forces, this method can effectively separate the composite strain of axial and bending measured by optical fiber into independent axial strain components and bending strain components. It captures the stress concentration phenomenon and deformation gradient changes at joint intersections of the anchor bolt, realistically and comprehensively restoring the actual stress and deformation characteristics of the anchor bolt. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the anchor bolt structure provided in an embodiment of this application; Figure 2 This is a schematic diagram of the anchor bolt cross-section structure provided in an embodiment of this application; Figure 3 A schematic diagram of the installation structure of the anchor bolt and fiber optic sensing unit provided in an embodiment of this application; Figure 4 The complete deformation process of the anchor rod provided in the embodiments of this application from the elastic stage to the plastic stage during loading.

[0018] In the figure: 1. Anchor bolt; 2. Groove; 3. Threaded end; 4. Fiber optic sensing unit; 5. Fiber optic demodulator; 6. Precast concrete test block; 7. Joint surface. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0020] This application provides a method for monitoring the axial and bending deformation of anchor bolts along their entire length. This method can solve the problem in related technologies where there is a lack of effective decoupling algorithms, making it impossible to separate the composite strain of axial and bending measured by optical fibers into independent axial strain components and bending strain components, thus making it difficult to accurately capture the true stress and deformation characteristics of anchor bolts in jointed rock masses.

[0021] The technical solution of this application is illustrated in detail below through a specific embodiment. This embodiment takes jointed rock mass anchoring structure as the application background and combines the anchored rock mass shear test for explanation.

[0022] I. Monitoring Preparation: Anchor Bolt Preparation and Fiber Optic Deployment Before implementing the monitoring method of this application, necessary preparatory work needs to be carried out, including the preparation of anchor bolts, the installation of distributed optical fiber sensing units, and the construction of the monitoring system.

[0023] Step S100: Anchor bolt preparation and grooving First, a high-strength steel bar with threads at both ends and a smooth, rounded center, totaling 400mm in length, was selected as the anchor rod base. Its diameter was 20mm, and the threaded portion at both ends was 30mm long. To accommodate and protect the fiber optic sensing unit, three grooves were machined axially along the smooth, rounded center of the anchor rod. The grooves were 1.5mm deep and wide, and evenly distributed at a 120° angle on the anchor rod cross-section. Furthermore, protective grooves, 3mm deep and wide, were machined in the threaded areas at both ends of the anchor rod to prevent direct contact between the nuts and the optical fiber during installation, thus avoiding damage. After grooving, the inner surface of the grooves was thoroughly cleaned with alcohol-soaked cotton swabs to remove oil and impurities, creating favorable conditions for fiber optic bonding. The anchor rod structure after grooving can be referenced. Figure 1 and Figure 2 .

[0024] Step S200: Install fiber optic sensing units on the anchor bolts. Three sheathed distributed optical fibers, each at least 2.5m long and 0.9mm in diameter, are selected. These three fibers are laid in three pre-fabricated grooves on the anchor bolt surface, and UV-cured adhesive is used to firmly bond the fibers to the bottom of the grooves, ensuring that the fibers deform in tandem with the anchor bolt substrate and preventing slippage and loosening during strain transfer. After bonding the fibers, the starting ends of the three fibers are connected to the subsequent demodulation equipment via module connectors.

[0025] Step S300: Data Acquisition System Configuration This embodiment employs a fully distributed fiber optic sensing demodulation device based on Rayleigh-OTDR (Rayleigh scattering time-domain reflectometry), such as the ODiSI 600 series 6-channel high-precision fiber optic demodulator from a certain company, as the core data acquisition device. This device possesses micro-strain level measurement accuracy and millimeter-level spatial resolution, enabling continuous distributed strain monitoring along the entire length of the fiber. The specific configuration is as follows: spatial resolution set to 0.65 mm, measurement range of ±12000 mm. It enables simultaneous monitoring of three optical channels to synchronously acquire strain data from three optical fibers.

[0026] After completing the above preparations, the prepared anchor bolt body is inserted into the central hole of a precast concrete test block (400mm×400mm×400mm). The test block adopts a split design and is mechanically spliced ​​to form a complete structure. Then, pre-prepared high-flowability cement grout is poured into the anchor bolt hole using a layered continuous pouring process to ensure that the grout fills the hole densely, eliminating air bubbles and voids in the hole, until the grout completely overflows from the hole, forming an effective bonding interface between the anchor bolt and the surrounding rock (concrete). After curing, subsequent loading and monitoring experiments can be carried out.

[0027] In some alternative embodiments, the number of grooves may be greater than 3. For example, four grooves may be machined axially in the smooth circular portion in the middle of the anchor rod, and the four grooves may be evenly distributed at a 90° angle on the cross-section of the anchor rod.

[0028] II. Methods for Monitoring Axial and Bending Deformation of Anchor Bolts Along Their Length The core of this application lies in a data processing and decoupling method. This method, based on strain data acquired from the three optical fibers mentioned above, achieves the separation and quantification of axial strain and bending strain. (Reference) Figure 3 The method includes the following steps: Step S1: Acquire strain data from each fiber optic sensing unit. During the anchored rock shear test, the fiber optic demodulator acquired distributed strain data along the entire length of the anchor rod in real time at a preset sampling frequency, simultaneously recording the load-displacement curve and the evolution of strain distribution along the entire length of the anchor rod. Specifically, strain data from three fiber optic sensing units (corresponding to the fibers in the three grooves) were acquired. Each strain data point consists of strain values ​​from a series of continuous monitoring points (spatial resolution 0.65 mm, i.e., one measuring point every 0.65 mm) along the length of the anchor rod, denoted as . (z) (z) , where z represents the position coordinate along the axial direction of the anchor rod.

[0029] Through distributed fiber optic sensing technology, high-density strain data can be continuously acquired along the entire length of the anchor bolt, avoiding the information loss problem that traditional point sensors can only monitor a limited number of points; the synchronous acquisition of multiple data streams provides complete raw data support for subsequent decoupling of axial and bending strain.

[0030] Optionally, after acquiring the raw strain data, the method further includes a step of preprocessing the strain data to repair any missing data.

[0031] Due to environmental factors or inherent characteristics of the optical fiber, missing values ​​(NaN) or outliers may exist in the data collected during actual monitoring. To address this, this invention proposes a polynomial fitting data repair method, comprising the following steps: Step S11: Check each monitoring point sequentially along the anchor bolt axis, identify missing data or abnormal values ​​exceeding the preset threshold in the strain data, mark them as data points to be repaired, and extract the position coordinates of the valid data points and their corresponding strain values.

[0032] Step S12: Based on the location coordinates and strain values ​​of the valid data points, a continuous distribution function between the strain values ​​and the location coordinates is constructed using a curve fitting method.

[0033] In this embodiment, the curve fitting method is a polynomial fitting method. Based on the effective strain data points, a polynomial fitting method is adopted. Successive order fitting of polynomials ( The polynomial expression is: .in, ( ) represents the fitting coefficients to be determined.

[0034] The fitting coefficients of polynomials of each order are calculated using the least squares method, and the corresponding mean square error is also calculated. In the formula, m is the number of monitoring data points; For the first The actual strain value of each valid data point; For the first The polynomial fit value corresponding to each valid data point.

[0035] The polynomial order and its fitting coefficients corresponding to the minimum mean square error are selected as the optimal fitting model.

[0036] Step S13: Predict and fill the strain value at the location of the data point to be repaired using the constructed functional relationship.

[0037] The optimal polynomial model is used to predict and calculate the strain values ​​at missing locations, thereby restoring the integrity of the data sequence. The entire data processing is completed automatically through a programming algorithm.

[0038] By repairing missing or abnormal data using a polynomial fitting method, the problem of incomplete data caused by fiber optic damage or environmental interference in field monitoring is effectively solved. The least squares method is used to automatically select the polynomial order, ensuring a balance between fitting accuracy and generalization ability, and improving the automation level of data processing and the reliability of results.

[0039] Besides polynomial fitting, other methods for preprocessing strain data to repair missing data include linear interpolation, cubic spline interpolation, radial basis function interpolation, moving average filtering, and weighted moving average.

[0040] Step S2: Based on the strain data of each fiber optic sensing unit, obtain the axial strain value of each monitoring point along the length of the anchor bolt.

[0041] For any monitoring point z, the strain values ​​measured at three different angles (z) (z) This is the combined strain resulting from the combined effects of axial tension (or compression) and bending at that point. According to the principles of mechanics of materials, bending strain exhibits a linear distribution across the cross-section, and its algebraic sum is zero. Therefore, by arithmetically averaging the three strain data, the influence of bending can be eliminated, thus obtaining the pure axial strain. The calculation formula is as follows: ; in, This is the axial strain value of the anchor rod at position z.

[0042] By taking the arithmetic mean of the three strain data, and utilizing the mechanical principle that the algebraic sum of bending strain on the cross section is zero, the influence of bending deformation on strain measurement is automatically eliminated. Pure axial strain data sequence can be obtained directly without additional temperature compensation or complex signal separation processing. The calculation is simple, the physical meaning is clear, and the calculation efficiency is high.

[0043] Step S3: Based on the strain data of each fiber optic sensing unit and the central angle between adjacent fiber optic sensing units, obtain the degree of cross-sectional bending of each fiber optic sensing unit at each monitoring point. The degree of cross-sectional bending is the total bending strain of the cross-section.

[0044] Specifically, the strain data difference between adjacent fiber optic sensing units is calculated and squared respectively; then the multiple squared values ​​are summed, the summation result is divided by a preset coefficient, and finally the square root of the quotient is taken to obtain the degree of cross-sectional bending of each fiber optic sensing unit at each monitoring point. The preset coefficient is a constant determined by the central angle between adjacent fiber optic sensing units.

[0045] To comprehensively evaluate the overall bending strength of the anchor bolt section, the total bending strain of the section is introduced. This indicator, based on the strain values ​​in three directions and their geometric relationship of 120° intervals, the total bending strain of the cross section, i.e., the degree of bending of the cross section, can be calculated using the following formula: ; Preset coefficients in the formula It is a constant determined by the central angle (120°) between adjacent fiber optic sensing units. It is a scalar that characterizes the overall bending degree of the anchor bolt cross-section at position z, effectively avoiding the one-sidedness of characterizing bending strain in a single direction.

[0046] The above calculation formula enables a comprehensive characterization of the cross-sectional bending state. The three fiber optic sensing units can only acquire local bending strain in their respective directions, while the actual bending direction of the anchor bolt is often arbitrary and may not coincide with any sensing direction. This formula combines the local components of the three directions into a single scalar index, which can capture the bending response of the cross-section in any direction, avoiding underestimation or underestimation of the bending degree due to inconsistencies between the sensing direction and the actual bending direction.

[0047] Secondly, it eliminates the reliance on prior information about the bending direction. The force direction of jointed rock anchors is affected by multiple factors such as surrounding rock deformation and structural surface distribution, making it difficult to predict accurately in advance and potentially changing as the deformation deepens. This indicator can provide an overall bending strength evaluation of the cross-section without requiring prior knowledge of the bending direction, enhancing the adaptability of the monitoring scheme to complex working conditions.

[0048] Thirdly, reducing multidimensional information to a single comprehensive indicator facilitates the establishment and application of engineering criteria. Compared to simultaneously analyzing strain components in three directions, the total bending strain of a single section makes it easier to set monitoring thresholds, plot distribution curves along the rod, and make lateral comparisons between different sections, which is beneficial for quickly locating key parts of anchor rod bending deformation.

[0049] Fourthly, the preset coefficients in the formula are rigorously derived from the geometric relationship of 120° equal division, which has a clear analytical basis. The calculation process does not require iteration or empirical calibration, thus ensuring the certainty and repeatability of the results.

[0050] Through steps S1 to S3 above, the system can calculate the axial strain point by point (e.g., every 0.65 mm) along the entire length of the anchor bolt. and total bending strain of the cross section These calculation results can generate real-time full-length deformation diagrams of the anchor bolt at different time points, such as... Figure 4 As shown, the complete deformation process from the elastic to the plastic stage is illustrated, clearly and quantitatively revealing the axial tensile and bending coupled deformation characteristics of jointed rock anchors under complex stress conditions. In the figure, the top row shows the strain values ​​along the anchor length of the fiber optic sensing units in the three slots, i.e., the strain data obtained in step S1. The first image in the bottom row shows the axial strain of the three slots obtained in step S2, the middle image shows the bending strain of the three slots obtained in step S3, and the third image shows the total strain, which is the strain change curve of the superposition of axial and bending strains. As can be seen from the figure, the axial strain is mainly concentrated in positive tensile strain throughout, while the bending strain undergoes a sharp reversal at point 0. The deformation mechanisms of the two are completely opposite, and their superposition masks their true stress characteristics. Only by separating them can the dangerous tensile-bending coupled working condition in the 0m core area be accurately determined.

[0051] Based on the above method, this application also provides a system for monitoring the axial and bending deformation of an anchor bolt along its entire length, which includes the following functional modules: The data acquisition module is used to acquire strain data from each fiber optic sensing unit. The axial strain calculation module is used to obtain the axial strain value of each monitoring point along the length of the anchor bolt based on the strain data of each fiber optic sensing unit. The cross-sectional bending degree calculation module is used to obtain the cross-sectional bending degree of each fiber optic sensing unit at each monitoring point by using the strain data of each fiber optic sensing unit and the central angle between adjacent fiber optic sensing units.

[0052] This system can be integrated into the host computer software of the fiber optic demodulator to achieve real-time data acquisition, processing, and visualization.

[0053] In summary, the method and system provided in this application effectively solve the problem of composite strain separation through a three-slot fiber optic deployment and a geometric decoupling algorithm. Compared with the prior art, its significant advantages are as follows: 1. With a spatial resolution of up to 0.65mm, it can monitor the entire length of the anchor bolt with high precision, enabling the acquisition of continuous deformation information along the entire length of the anchor bolt and accurately capturing sudden changes in local deformation at key locations such as joint surfaces.

[0054] 2. By using a three-slot arrangement scheme and a strain decoupling algorithm, axial strain and bending strain can be independently separated from the composite signal, comprehensively reflecting the deformation state of the anchor bolt, and providing key data for accurately evaluating the bearing characteristics of the anchor bolt under tension and shear combined stress.

[0055] 3. The polynomial fitting algorithm effectively corrects the data loss problem that may occur during the monitoring process, ensuring the integrity of the data and the continuity of the analysis.

[0056] 4. It has strong environmental adaptability and inherits the advantages of distributed optical fiber sensing technology, such as resistance to electromagnetic interference, corrosion resistance and good long-term stability. It is suitable for anchor monitoring under complex geological conditions such as jointed rock masses and can capture deformation characteristics from elasticity to failure.

[0057] In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0058] It should be noted that in this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0059] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A method for monitoring the axial and bending deformation of an anchor bolt along its entire length, characterized in that, Includes the following steps: The strain data of each fiber optic sensing unit is acquired. Each fiber optic sensing unit is arranged along the axial direction of the anchor rod and distributed circumferentially on the cross section of the anchor rod. The strain data consists of the strain values ​​of each monitoring point along the length direction of the anchor rod detected by each fiber optic sensing unit. Based on the strain data from each fiber optic sensing unit, the axial strain value at each monitoring point along the length of the anchor bolt is obtained. Based on the strain data of each fiber optic sensing unit and the central angle between adjacent fiber optic sensing units, the degree of cross-sectional bending of each fiber optic sensing unit at each monitoring point is obtained.

2. The method for monitoring the axial and bending deformation of an anchor bolt along its entire length as described in claim 1, characterized in that, Based on the strain data from each fiber optic sensing unit, the axial strain values ​​at each monitoring point along the length of the anchor bolt are obtained, including: The strain data from each fiber optic sensing unit are arithmetically averaged to obtain the axial strain value at each monitoring point along the length of the anchor bolt.

3. The method for monitoring the axial and bending deformation of the anchor bolt along its entire length as described in claim 1, characterized in that, Based on the strain data of each fiber optic sensing unit and the central angle between adjacent fiber optic sensing units, the degree of cross-sectional bending of each fiber optic sensing unit at each monitoring point is obtained, including: The strain data difference between adjacent fiber optic sensing units is calculated and squared respectively. Then, the multiple squared values ​​are summed, the summation result is divided by a preset coefficient, and finally the square root of the quotient is taken to obtain the degree of cross-sectional bending of each fiber optic sensing unit at each monitoring point. The preset coefficient is a constant determined by the central angle between adjacent fiber optic sensing units.

4. The method for monitoring the axial and bending deformation of the anchor bolt along its entire length as described in claim 1, characterized in that, After acquiring the strain data from each fiber optic sensing unit, the method further includes: The strain data is preprocessed.

5. The method for monitoring the axial and bending deformation of the anchor bolt along its entire length as described in claim 4, characterized in that, Preprocessing of strain data includes: Each monitoring point is checked sequentially along the anchor bolt axis to identify missing data or abnormal values ​​exceeding the preset threshold in the strain data. These are marked as data points to be repaired, and the location coordinates and corresponding strain values ​​of the valid data points are extracted. Based on the location coordinates and strain values ​​of valid data points, a continuous distribution function between strain values ​​and location coordinates is constructed using a curve fitting method. The strain value at the location of the data point to be repaired is predicted and filled using the constructed functional relationship.

6. The method for monitoring the axial and bending deformation of an anchor bolt along its entire length as described in claim 5, characterized in that, The curve fitting method is a polynomial fitting method; The fitting coefficients of polynomials of each order are calculated using the least squares method, and the corresponding mean square error is also calculated. The polynomial order and its fitting coefficients corresponding to the minimum mean square error are selected as the optimal fitting model.

7. The method for monitoring the axial and bending deformation of the anchor bolt along its entire length as described in claim 5, characterized in that, Based on the preprocessed strain data, the steps of obtaining the axial strain value and obtaining the degree of cross-sectional bending are performed.

8. A system for monitoring the axial and bending deformation of an anchor bolt along its entire length, characterized in that, include: The data acquisition module is used to acquire strain data from each fiber optic sensing unit. The axial strain calculation module is used to obtain the axial strain value of each monitoring point along the length of the anchor bolt based on the strain data of each fiber optic sensing unit. The cross-sectional bending degree calculation module is used to obtain the cross-sectional bending degree of each fiber optic sensing unit at each monitoring point based on the strain data of each fiber optic sensing unit and the central angle between adjacent fiber optic sensing units.

9. A device for monitoring the axial and bending deformation of an anchor bolt along its entire length, characterized in that, The device includes a processor, a memory, and a computer program stored in the memory and executable by the processor, wherein when the computer program is executed by the processor, it implements the steps of the anchor bolt full-length axial and bending deformation monitoring method as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a program for monitoring the axial and bending deformation of the anchor bolt along its entire length, wherein when the program is executed by a processor, it implements the steps of the method for monitoring the axial and bending deformation of the anchor bolt along its entire length as described in any one of claims 1 to 7.

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