Method for synchronously monitoring surrounding rock deformation and supporting structure deformation in tunnel construction

Abstract

The invention belongs to the technical field of tunnel construction deformation monitoring, and particularly discloses a tunnel construction surrounding rock deformation and support structure deformation synchronous monitoring method, which comprises the following steps of: arranging monitoring point pairs of surrounding rock and support structures on a tunnel physical monitoring section, synchronously acquiring deformation data by using the monitoring point pairs, and then executing graded time synchronous verification; through a dual synchronization verification mechanism, the problem of time misalignment is effectively eliminated, and it is also ensured that data used for collaborative deformation analysis has real and reliable time sequence consistency in the physical sense. Meanwhile, the surrounding rock displacement and support stress response curves of the same monitoring point pair are superposed under a unified time axis on the basis of completing time synchronism verification, the coupling relation between the morphological characteristics and the time sequence is comprehensively analyzed, the deformation cooperation state at the point is accurately judged, refined deformation behavior analysis based on the physical position is achieved, and the accuracy of deformation behavior analysis is improved. The early-stage precursor of collaborative degradation can be captured, and the timeliness of risk early warning is remarkably improved.

Description

Technical Field

[0001] This invention belongs to the field of tunnel construction deformation monitoring technology, and specifically discloses a method for synchronous monitoring of surrounding rock deformation and support structure deformation during tunnel construction. Background Technology

[0002] In water conservancy engineering construction, extensive excavation and support work for hydraulic tunnels is frequently involved. During tunnel construction, the surrounding rock, affected by excavation disturbance, undergoes stress redistribution and deformation response. The surrounding rock and the support structure together constitute an interacting mechanical system. The deformation load of the surrounding rock is transferred and borne by the support structure, and the coordination of their deformations directly reflects the safety status of the overall structure. Therefore, achieving simultaneous monitoring of the deformation of the surrounding rock and the deformation of the support structure is of paramount importance for ensuring project safety.

[0003] Existing technologies include solutions designed for synchronous monitoring. For example, Chinese invention patent application CN119845176A discloses a synchronous monitoring system and construction method for tunnel surrounding rock deformation and support deformation. This solution employs a mechanical integrated monitoring device comprising an "outer displacement component" fixed to the support steel arch and an "inner displacement component" in contact with the surrounding rock via a spring, respectively sensing the displacement of the support and the surrounding rock. A vision unit mounted on a mobile trolley simultaneously captures images of targets mounted on the inner and outer components, thereby obtaining the displacement of both components at the same time. Finally, by comparing the difference in displacement between the inner and outer targets, a qualitative determination is made as to whether there is separation or void between the surrounding rock and the support.

[0004] However, this technical solution has the following limitations in implementation: First, the synchronization achieved by this solution relies on the vision unit capturing images of two targets at the same physical moment, which is limited to the synchronization of the acquisition action and does not involve synchronization verification. When there is clock drift, image processing delay, network transmission jitter, or equipment malfunction within the system, the recorded synchronization data may not be aligned on the timeline. Due to the lack of effective synchronization verification methods, subsequent analysis based on the time sequence may be based on a distorted time reference, leading to misjudgment of the mechanism.

[0005] Secondly, the deformation data analysis in this scheme is limited to scalar subtraction of the displacement of the surrounding rock and the support, and uses a fixed displacement difference threshold as the early warning criterion. Essentially, it is a static, result-oriented, single-index alarm strategy. Its deformation analysis is coarse-grained, lacking a fine characterization of the dynamic coupling characteristics of the deformation process of the two, making it difficult to identify early signs of coordinated deterioration, and easily causing early warning delays. Summary of the Invention

[0006] To solve the above-mentioned technical problems, or at least partially solve them, the present invention provides a method for synchronous monitoring of surrounding rock deformation and support structure deformation during tunnel construction.

[0007] The objective of this invention can be achieved through the following technical solution: a method for synchronous monitoring of surrounding rock deformation and support structure deformation during tunnel construction, comprising: S1, on the same physical monitoring section of the tunnel, deploying surrounding rock displacement sensing elements and support stress response sensing elements according to spatial position correspondence to form a monitoring point pair.

[0008] S2. At a preset acquisition cycle, the time series outputs of the surrounding rock displacement sensing element and the support stress response sensing element at each monitoring point are collected synchronously.

[0009] S3. Perform hierarchical time synchronization verification on the output time series, including: daily synchronization verification based on unified time stamp and event-triggered supplementary verification based on external construction disturbance events.

[0010] S4. Using data verified by time synchronization, the displacement time curve of the surrounding rock and the stress response time curve of the support at the same monitoring point are superimposed on a unified time axis. The morphological characteristics and temporal relationship of the two curves are analyzed to determine whether the surrounding rock and the support structure at that point are in a state of coordinated deformation or a state of coordinated abnormality.

[0011] S5. Integrate the collaborative deformation state judgment results of each monitoring point pair to trigger corresponding construction risk warnings.

[0012] Combining all the above technical solutions, the positive effects of this invention are as follows: 1. After setting up monitoring points for the surrounding rock and support structure on the tunnel physical monitoring section, this invention performs hierarchical time synchronization verification after synchronously collecting deformation data using the monitoring points. This includes daily synchronization verification based on a unified time stamp and event-triggered supplementary verification based on external construction disturbance events. Through the dual synchronization verification mechanism, not only is the time inaccuracy problem caused by equipment clock drift, communication delay, or sensor abnormality effectively eliminated, but the data used for collaborative deformation analysis also ensures that the data has a real and reliable temporal consistency in a physical sense.

[0013] 2. Based on the completion of time synchronization verification, this invention superimposes the surrounding rock displacement and support stress response curves of the same monitoring point pair on a unified time axis, comprehensively analyzes their morphological characteristics and temporal coupling relationship, accurately identifies the deformation coordination state at the point, realizes refined deformation behavior analysis based on physical location, overcomes the limitations of traditional coarse-grained analysis that only relies on displacement difference, helps to capture early signs of coordinated deterioration, and significantly improves the foresight and timeliness of risk warning.

[0014] 3. After identifying the collaborative anomaly state, the present invention implements graded early warning based on the spatial distribution characteristics of the collaborative anomaly in the tunnel cross section and longitudinal direction, which significantly enhances the spatial resolution capability and engineering decision support value of the early warning results. Attached Figure Description

[0015] The present invention will be further described with reference to the accompanying drawings, but the embodiments in the drawings do not constitute any limitation on the present invention. For those skilled in the art, other drawings can be obtained based on the following drawings without creative effort.

[0016] Figure 1 This is a diagram illustrating the implementation steps of the method of the present invention.

[0017] Figure 2 This is a flowchart of the daily synchronization verification process based on a unified time stamp in this invention.

[0018] Figure 3 This is a flowchart of the event-triggered supplementary verification process based on external construction disturbance events in this invention. Detailed Implementation

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

[0020] See Figure 1 As shown, the present invention proposes a method for synchronous monitoring of deformation of surrounding rock and support structure during tunnel construction, including the following steps: S1, on the same physical monitoring section of the tunnel, displacement sensing elements inside the surrounding rock and stress response sensing elements of the support are arranged according to the spatial correspondence to form a monitoring point pair.

[0021] When conducting synchronous deformation monitoring of tunnel surrounding rock and support structure, the basic premise is to set up monitoring points for the deformation of surrounding rock and support structure. In order to characterize the collaborative working mechanism of the surrounding rock support system, the spatial distance between the two types of monitoring points should not be too far. If it is too far, the monitoring data will not be able to truly reflect the interaction relationship between the same rock mass unit and the corresponding support component, thereby weakening the accuracy and reliability of collaborative state identification.

[0022] Specifically, in the synchronous monitoring of tunnel surrounding rock support, this invention does not directly monitor two displacement quantities, but instead uses surrounding rock displacement sensing elements and support stress response sensing elements to simultaneously acquire the temporal data of surrounding rock deformation and support stress. By jointly analyzing the correlation between the two in terms of time evolution and morphological characteristics, it deeply diagnoses the load transfer state and collaborative working performance. Compared with simple displacement difference comparison, it has a greater insight into mechanical mechanisms and early risk identification capabilities.

[0023] To address the above considerations, this invention establishes a monitoring point pair by simultaneously deploying internal rock displacement sensing elements and support stress response sensing elements on the same physical monitoring section according to a clear spatial correspondence, thereby ensuring the basis for collaborative analysis of the collected data in the spatial dimension.

[0024] As a preferred implementation of the above steps, the specific layout process of the monitoring points for the surrounding rock and support is as follows: at the selected monitoring section, the boreholes of the multi-point displacement gauge used to sense the internal displacement of the surrounding rock are laid out at the preset monitoring position, and its shallowest anchor point is located near the interface between the surrounding rock and the future support structure.

[0025] Understandably, multi-point displacement gauges reflect displacement at different depths within the surrounding rock through multiple deep anchoring points. The shallowest anchoring point is located near the interface between the surrounding rock and the support structure, effectively representing the surface deformation of the surrounding rock that will interact with the support structure. The displacement at this point is the direct source of the actual load borne by the support structure. If this point is too deep, it cannot accurately reflect the deformation of the surrounding rock acting on the support; if it is not aligned with the interface, it loses its mechanical correspondence with the support response.

[0026] This layout ensures that the surrounding rock displacement data and the support response data strictly correspond on the mechanical boundary, providing a physical basis for subsequent collaborative state identification.

[0027] During the initial construction of the support structure, stress sensing elements for sensing the mechanical response of the support structure are embedded at the vertical or normal projection positions of the multi-point displacement gauge boreholes.

[0028] To further understand, after tunnel excavation, the surrounding rock deforms radially into the tunnel, and the support structure mainly bears the compression or bending forces from this direction. Therefore, the main direction of surrounding rock deformation is usually perpendicular to the tunnel profile. By placing stress sensing elements on the support structure at the vertical or normal projection positions of the multi-point displacement gauge borehole, it can be ensured that the displacement of the surrounding rock in this direction directly acts on the support structure at the corresponding position, and the measured support response is indeed caused by the surrounding rock deformation monitored by the borehole.

[0029] A multi-point displacement gauge and a stress sensing element are combined to form a monitoring point pair.

[0030] S2. At a preset acquisition cycle, the time series outputs of the surrounding rock displacement sensing element and the support stress response sensing element at each monitoring point are collected synchronously.

[0031] S3. Perform hierarchical time synchronization verification on the output time series, including: daily synchronization verification based on unified time stamp and event-triggered supplementary verification based on external construction disturbance events.

[0032] Although the surrounding rock displacement sensing element and the support stress response sensing element collected data synchronously at each monitoring point, the obtained time series may not be truly synchronized due to factors such as equipment clock deviation, communication delay, or differences in system processing. If the data is not synchronized, it will lead to misjudgments of the sequential relationship and synergistic state between the deformation of the surrounding rock and the support.

[0033] To this end, the present invention performs synchronization verification on the collected time series. On the one hand, routine verification is achieved through daily synchronization verification using a unified time stamp. On the other hand, supplementary synchronization verification based on physical mechanisms is carried out in conjunction with the response characteristics caused by external construction disturbance events to ensure that the data used for analysis is truly aligned in time.

[0034] See Figure 2 As shown, the daily synchronization verification based on a unified time stamp is implemented as follows: a data acquisition unit controlled by a unified time source is configured for the multi-point displacement gauge and stress sensing element of each monitoring point pair, so that each data acquisition point is assigned a precise timestamp based on the unified time source.

[0035] In one specific embodiment, the unified time source can be a BeiDou / GPS satellite time synchronization module integrated in each data acquisition unit, which provides a unified clock signal to all acquisition units through a network time synchronization protocol.

[0036] Applying to the above operational instructions, by configuring a data acquisition unit controlled by a unified time source, it is ensured that all observation data are tagged with physically consistent time stamps. This is the basis for eliminating clock drift between devices and ensuring time comparability.

[0037] Within a single acquisition cycle, the dataset with precise timestamps generated by the multi-point displacement gauges and stress sensing elements within that cycle is extracted.

[0038] Based on precise timestamps, we can verify whether the time coverage of the datasets acquired by the multi-point displacement gauges and the datasets acquired by the stress sensing elements overlap, and whether the data acquisition points of the two correspond one-to-one on the time axis within the same overlapping time interval.

[0039] If the time coverage overlaps and the data collection points of the two data collection points correspond one-to-one on the time axis, then the monitoring point is determined to be synchronous with the data collection process in the current period; otherwise, it is determined that there is a daily collection out-of-synchronization.

[0040] In a preferred embodiment, a one-to-one correspondence on the time axis means that for any sampling time, both datasets have data points within an allowable time deviation of ±10 milliseconds before and after that time.

[0041] Applying the above operational instructions, it is necessary to check whether the two types of sensors output data simultaneously at the same time point within the same acquisition cycle, based on a unified timestamp. Only when their time coverage overlaps and the sampling points within the overlapping interval correspond one-to-one can the subsequent analysis of the deformation time series relationship be guaranteed to be reliable; otherwise, even if data is acquired simultaneously, false time series conclusions may result due to sampling misalignment.

[0042] The aforementioned daily synchronization verification is essentially a sampling consistency verification mechanism based on precise timestamps, used to eliminate pseudo-synchronization problems caused by system asynchrony at the data source, providing a reliable temporal basis for subsequent collaborative deformation analysis.

[0043] See Figure 3 As shown, the specific implementation process of event-triggered supplementary verification based on external construction disturbance events is as follows: select strong disturbance events with clear start and end time nodes during tunnel construction, and use their start time as the reference time for time synchronization supplementary verification.

[0044] It should be added that tunnel construction is often accompanied by strong disturbance events such as blasting, excavation progress, and support construction. These events will significantly stimulate the dynamic response of the surrounding rock and support structure, forming response signals with clear physical start times and characteristic waveforms in the monitoring data.

[0045] This invention utilizes external disturbance events with clear temporal markers as synchronous verification benchmarks. By identifying characteristic mutations induced by the same event in the response signals of the surrounding rock and support and their occurrence sequence, it verifies whether the time series of the two conform to the mechanical transmission logic of the surrounding rock deforming first and the support responding later, thereby achieving high-confidence supplementary synchronous verification.

[0046] Extract the time series data output by the surrounding rock displacement sensing element and the support stress response sensing element at each monitoring point after the reference time.

[0047] Starting from the baseline time in the extracted time series data, response mutations are identified based on data differencing. When a response mutation is identified, the time of the mutation is marked as the characteristic response of the corresponding strong disturbance event in the time series.

[0048] It should be noted that although construction disturbances have a definite occurrence time, this time cannot be directly equated with the actual response start time of the surrounding rock or support structure in their respective time series. This is because the disturbance energy needs to travel through a certain path and time before it can act on the monitoring location, thereby causing significant changes in the time series of surrounding rock displacement and support mechanical response, which manifests as a deviation from the original trend and forms identifiable response abrupt change characteristics.

[0049] Therefore, it is necessary to extract the characteristic response time induced by the disturbance event from the time series through mutation detection, and use it as a time marker of the actual response of the surrounding rock and support, so as to provide a reliable basis for subsequent analysis of the mechanical transmission logic of the response signals of the two.

[0050] In the optional implementation of the above scheme, the process of response mutation identification based on data difference is as follows: starting from the reference time, calculate the change amplitude of the current time data and the previous time data point by point in the extracted time series data.

[0051] The aforementioned change amplitude refers to the absolute value of the difference between the current data value and the previous data value, reflecting the instantaneous rate of change of the monitored physical quantity within a unit sampling interval. In the stable phase, the deformation of the surrounding rock or support is usually slow and continuous, with a small change amplitude; however, when subjected to construction disturbance, the structure will respond rapidly, causing the monitored value to jump significantly in a short period of time, at which point the change amplitude will increase significantly.

[0052] The real-time calculated change amplitude is compared with the mutation discrimination threshold within a time window starting from the reference time. If the change amplitude calculated at a certain time within the time window exceeds the mutation discrimination threshold, a mutation is identified.

[0053] It should be noted that in the process of response mutation identification, a time window constraint starting from the construction disturbance reference time is introduced. This aims to limit the comparison between the change amplitude and the mutation discrimination threshold to a physically reasonable response period. Without this time constraint, mutations caused by other factors later may be misjudged as responses to the current construction disturbance, leading to distortion of the time series analysis.

[0054] The ratio of the geometric distance from the monitoring point to the disturbance source to the propagation speed of the stress wave generated by the blast in the surrounding rock is used as the length of the time window to ensure coverage of the entire process from the occurrence of the disturbance signal to its arrival at the monitoring location and the triggering of an observable response.

[0055] The mutation discrimination threshold can be determined based on the normal fluctuation level of the monitoring data under undisturbed operating conditions. It is generally taken as several times the standard deviation of the normal fluctuation amplitude, such as 3 times the standard deviation, to ensure that the identified mutation is a statistically significant and effective response signal.

[0056] The above dual constraints can effectively ensure that the extracted feature responses are indeed caused by the target construction disturbance, thereby improving the reliability of synchronous verification and the accuracy of timing identification.

[0057] Check whether the marked characteristic response time on the surrounding rock displacement time series occurs before the marked characteristic response time on the corresponding support stress response time series. If so, it is determined that it conforms to the physical time sequence logic that the change in the characteristic of the surrounding rock displacement precedes the change in the characteristic of the support stress response.

[0058] If all the monitored points being tested conform to the physical timing logic, then the data collected in this batch is determined to have time synchronization.

[0059] The aforementioned supplementary verification based on construction event disturbances essentially reflects whether the monitoring data conforms to the dynamic response mechanism of the surrounding rock support system during the actual physical loading process. It is a data credibility criterion based on physical mechanisms. If the measured response time sequence conforms to this logic, it indicates that the data is real and reliable in the time dimension and can be used for collaborative deformation analysis. If the time sequence is reversed, it indicates that there are problems such as time asynchrony, sensor abnormality or data distortion, which need to be eliminated.

[0060] It should be added that, in the hierarchical time synchronization verification system of the present invention, daily synchronization verification is a normalized means to continuously ensure the consistency of data time for each monitoring point in each collection cycle; while event-triggered supplementary verification is an occasional verification, which is a supplementary means to normalized verification and is automatically activated only when a strong disturbance event occurs.

[0061] This is because construction disturbance events are intermittent and discontinuous, not continuous. Furthermore, while event-triggered verification can validate the temporal logic of the surrounding rock and support based on physical response mechanisms, it only reflects the local synchronization state during the disturbance period and cannot cover the sampling alignment throughout the entire timeframe. Therefore, routine synchronization verification ensures reliability throughout the entire process, while event-triggered verification strengthens the credibility of critical events. Together, they form a hierarchical and complementary time synchronization guarantee mechanism.

[0062] The innovative implementation of hierarchical time synchronization verification also includes fault warning, which is implemented as follows: If the daily synchronization verification determines that a certain monitoring point pair has daily acquisition out of sync for several consecutive cycles, a fault warning is triggered, indicating that the point pair may have problems such as sensor clock abnormality, communication interruption or acquisition unit failure, and the abnormal state is recorded. When a strong disturbance event occurs later, an event-triggered supplementary verification for the point pair is automatically triggered to verify and further confirm the data reliability of the monitoring point pair.

[0063] S4. Using data verified by time synchronization, the displacement time curve of the surrounding rock and the stress response time curve of the support at the same monitoring point are superimposed on a unified time axis. The morphological characteristics and temporal relationship of the two curves are analyzed to determine whether the surrounding rock and the support structure at that point are in a state of coordinated deformation or a state of coordinated abnormality.

[0064] After completing the time synchronization verification, this invention conducts a joint analysis based on the morphological characteristics and temporal coupling relationship of the time series of surrounding rock displacement and support stress response. This breaks through the traditional lag warning mode that only relies on the displacement difference exceeding the limit. Through fine-grained analysis of the coordinated deformation process of surrounding rock support, this method can identify coordinated deterioration at the early stage of time lag or trend deviation in support response, realize early detection and early warning of risk precursors, and significantly improve the accuracy and timeliness of deformation state identification.

[0065] In the above-mentioned scheme, the implementation process of S4 is as follows: plot the displacement-time curve of the surrounding rock and the support stress response-time curve of each monitoring point pair in the same coordinate system.

[0066] The inflection points of the two curves are identified by the change in the sign of the second derivative, and the timestamp of each inflection point is recorded.

[0067] The inflection point mentioned above represents the moment when the deformation rate on the time curve undergoes a significant change.

[0068] The inflection points of surrounding rock displacement and support stress response are paired according to their temporal proximity to construct a set of inflection point pairs. Two inflection points with similar abscissas are grouped into a pair.

[0069] By pairing inflection points, an event-level correspondence between the surrounding rock and the support structure during the deformation evolution process was established, enabling subsequent quantitative analysis of the temporal logic and degree of synergy between the surrounding rock deformation and the support stress response at the turning point.

[0070] For each inflection point, calculate the lag time of the support stress response inflection point relative to the surrounding rock displacement inflection point, and compare this lag time with the preset physical reasonable response window.

[0071] Given that the surrounding rock, as the initial bearing medium, takes the lead in stress redistribution and deformation after tunnel excavation, while the support structure, as a passive force-bearing system, depends on the transmission and effect of the deformation of the surrounding rock to the contact interface between the support and the surrounding rock, the physical mechanism determines that the moment when the support structure produces a significant mechanical response must lag behind the moment when the surrounding rock undergoes deformation and inflection.

[0072] By calculating the lag time of the stress response inflection point of each inflection point relative to the displacement inflection point of the surrounding rock, the dynamic coupling timeliness of the surrounding rock support system at the monitoring point can be quantitatively characterized, thereby determining whether it is in a reasonable collaborative working state.

[0073] The physically reasonable response window reflects the local dynamic delay range required for local deformation of the surrounding rock to be transmitted to the adjacent support structure and induce an observable mechanical response under given surrounding rock support contact conditions. Specifically, this window is set by first using the ratio of the distance between the shallowest anchor point in the surrounding rock monitoring points and the response point of the support structure to the stress wave propagation velocity in the surrounding rock medium as the theoretical time delay, and then using the closed interval from 0 to the theoretical time delay as the physically reasonable response window.

[0074] The proportion of inflection point pairs whose statistical lag time falls within a reasonable window to the total number of inflection point pairs is denoted as the proportion of collaborative inflection point pairs.

[0075] Based on the identified inflection point locations, the two time curves are divided into several characteristic segments, including rising segments, falling segments, and stable segments.

[0076] Specifically, taking the surrounding rock displacement time curve as an example, the support stress response time curve is similar. The process of dividing the rising segment, falling segment and stable segment is as follows: First, extract the timestamps of all inflection points on the curve to form an ordered sequence, which serves as the segment boundary.

[0077] Subsequently, for each interval defined by a pair of adjacent inflection points, trend judgment is made based on the first difference of the displacement sequence within the interval. If the displacement within the interval increases monotonically and there is no reversal of direction, it is determined to be an upward segment. If the displacement within the interval decreases monotonically and there is no reversal of direction, it is determined to be a downward segment. If the absolute value of the first difference within the interval is close to zero, it is determined to be a stationary segment.

[0078] Finally, to avoid generating too many fragmented segments due to minor fluctuations, adjacent short time periods of the same type can be merged to form more stable characteristic segments.

[0079] For characteristic segments of the same type in the displacement-time curve inside the surrounding rock and the support stress response-time curve, the segment-level overlap of the rising segment, falling segment and stable segment is obtained by calculating the ratio of the intersection length and union length of the two segments on the time axis.

[0080] If a monitoring point meets the following conditions simultaneously, it is determined that the surrounding rock and the support structure at that point are in a state of coordinated deformation; otherwise, it is determined that they are in a state of coordinated abnormality.

[0081] i) The proportion of collaborative inflection points reaches or exceeds the median proportion.

[0082] The aforementioned median percentage refers to the median percentage of the collaborative inflection point pairs among all monitoring point pairs. It serves as the statistical center for characterizing the typical level of collaboration in the engineering environment. When the collaborative inflection point pair percentage of a certain monitoring point pair reaches or exceeds the median percentage, it indicates that more than half of the inflection point pairs meet the reasonable timing of the surrounding rock changing first and the support responding later, indicating that the surrounding rock and support at that point have good collaboration in terms of event response.

[0083] ii) The overlap of segments in the rising, falling, and stable segments is greater than the consensus threshold.

[0084] The aforementioned coordination and consistency threshold is a critical value used to determine whether the overlap of characteristic segments is high enough. It represents the minimum acceptable standard for the degree of temporal overlap between the surrounding rock and the support in the same deformation stage. Specifically, it can be based on a large amount of historical monitoring data of known stable segments, statistically analyze the average overlap of various characteristic segments under normal coordination conditions, and take its lower limit, such as the mean minus 1 standard deviation.

[0085] When the overlap of the rising, falling, and stable segments is greater than the coordination and consistency threshold, it means that the displacement inside the surrounding rock and the stress response of the support exhibit highly synchronized temporal behavior in all deformation stages during the overall deformation evolution process. That is, the two enter and exit the same deformation state within the same time period, reflecting that the surrounding rock and the support structure have good collaborative working performance at the process level.

[0086] It can be noted that the proportion of synergistic inflection points reflects whether the surrounding rock and support meet the physical time sequence logic of surrounding rock changing first and support responding later at the level of key deformation events, which belongs to the event-level synergy measurement.

[0087] The overlap of the ascending, descending, and stable segments at the segment level describes the consistency of their stage behavior throughout the entire deformation and evolution process, and belongs to the process-level synergy measurement.

[0088] The two complement each other from two dimensions: discrete key points and continuous time period morphology. Together, they constitute a multi-scale and refined basis for identifying the coordinated deformation state of surrounding rock support.

[0089] S5. Integrate the collaborative deformation state judgment results of each monitoring point pair to trigger corresponding construction risk warnings.

[0090] After determining the coordinated deformation state of each monitoring point pair, it is important to understand that since these monitoring points are discrete points distributed locally across the tunnel cross-section, they only reflect the local mechanical behavior at their location and cannot represent the overall state of the entire tunnel structure. If a global early warning is based solely on individual anomalies or a simple summary of anomalies, it can easily lead to coarse-grained warnings, ambiguous spatial orientation, and even false alarms or missed judgments, making it difficult to support accurate construction decisions.

[0091] To this end, this invention constructs a hierarchical and zoned risk early warning mechanism based on the spatial distribution characteristics of collaborative anomaly monitoring point pairs, thereby improving the spatial resolution of early warning and the targeted nature of engineering response.

[0092] Specifically, the early warning operation is as follows: count the number of monitoring point pairs that are in a state of coordinated abnormality among all monitoring point pairs.

[0093] When a single monitoring point is in a state of coordinated abnormality, a local attention warning is triggered.

[0094] Understandably, coordinated anomalies in a single monitoring point pair usually indicate initial signs of deterioration at that local location, such as poor contact, support failure, or loosening of the surrounding rock. Such anomalies are insufficient to determine overall structural instability, but they are precursory and warrant attention.

[0095] When multiple monitoring point pairs within the same monitoring section, or corresponding monitoring point pairs between adjacent sections along the tunnel axis, are simultaneously in a coordinated abnormal state, a regional risk warning is triggered.

[0096] Understandably, if multiple measuring points within the same cross-section show abnormalities simultaneously, it indicates that the surrounding rock support system of that cross-section has experienced systematic and coordinated deterioration in the circumferential direction.

[0097] If the measuring points at the same location on adjacent cross sections show synchronous anomalies, it indicates that the risk has continuity and expansion along the tunnel axis.

[0098] Both of the above scenarios exhibit clear characteristics of spatial clustering anomalies. These spatial clustering anomalies have gone beyond the scope of random noise or isolated faults. At this point, relying solely on local attention and early warning is insufficient to reflect the severity and urgency of the risk. By triggering regional risk early warnings, the on-site management can be promptly notified to take intervention measures to curb the further evolution of the risk and ensure construction and structural safety.

[0099] The above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments can be implemented, in whole or in part, in the form of a computer program product.

[0100] Those skilled in the art will recognize that the modules and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0101] In addition, the functional modules in the various embodiments of this application can be integrated into one processing module, or each module can exist physically separately, or two or more modules can be integrated into one module.

[0102] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0103] Finally, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for synchronously monitoring the deformation of surrounding rock and support structure during tunnel construction, characterized in that, include: On the same physical monitoring section of the tunnel, surrounding rock displacement sensing elements and support stress response sensing elements are deployed according to spatial location correspondence to form a monitoring point pair; The time series outputs of the surrounding rock displacement sensing element and the support stress response sensing element at each monitoring point are collected synchronously at a preset collection period. Hierarchical time synchronization verification is performed on the output time series, including: daily synchronization verification based on unified time stamp and event-triggered supplementary verification based on external construction disturbance events; Using data verified by time synchronization, the displacement time curve of the surrounding rock and the stress response time curve of the support at the same monitoring point are superimposed on a unified time axis. The morphological characteristics and temporal relationship of the two curves are analyzed to determine whether the surrounding rock and the support structure at that point are in a state of coordinated deformation or a state of coordinated abnormality. By integrating the results of the coordinated deformation status determination of various monitoring points, corresponding construction risk warnings are triggered.

2. The method for synchronous monitoring of surrounding rock deformation and support structure deformation during tunnel construction as described in claim 1, characterized in that: The formation of monitoring point pairs includes the following: At the selected monitoring section, the boreholes of the multi-point displacement gauge used to sense the internal displacement of the surrounding rock are laid at the preset monitoring position, and its shallowest anchor point is located near the interface between the surrounding rock and the future support structure. During the initial construction of the support structure, stress sensing elements for sensing the mechanical response of the support structure are embedded at the vertical or normal projection positions of the multi-point displacement gauge boreholes. A multi-point displacement meter and a stress sensing element are combined to form a monitoring point pair.

3. The method for synchronous monitoring of surrounding rock deformation and support structure deformation during tunnel construction as described in claim 1, characterized in that: The daily synchronization verification based on the unified time stamp is implemented as follows: Each monitoring point pair of multi-point displacement gauges and stress sensing elements is equipped with a data acquisition unit controlled by a unified time source, so that each data acquisition point is given a precise timestamp based on the unified time source. Within a single acquisition cycle, extract the dataset with precise timestamps generated by the multi-point displacement gauges and stress sensing elements within that cycle; Based on precise timestamps, we examine whether the time coverage of the datasets acquired by the multi-point displacement gauges and the datasets acquired by the stress sensing elements overlap, and whether the data acquisition points of the two correspond one-to-one on the time axis within the same overlapping time interval. If the time coverage overlaps and the data collection points of the two data points correspond one-to-one on the time axis, then the monitoring point is determined to have synchronization in data collection within the current period; otherwise, it is determined that there is a daily collection out-of-synchronization.

4. The method for synchronous monitoring of surrounding rock deformation and support structure deformation during tunnel construction as described in claim 1, characterized in that: The specific implementation process of the event-triggered supplementary verification based on external construction disturbance events is as follows: Strong disturbance events with clear start and end time nodes are selected during tunnel construction, and their start time is used as the reference time for time synchronization supplementary verification. Extract the time series data output by the surrounding rock displacement sensing element and the support stress response sensing element at each monitoring point after the reference time; In the extracted time series data, response mutations are identified based on data differencing starting from the base time. When a response mutation is identified, the time when the mutation occurs is marked as the characteristic response of the corresponding strong disturbance event in the time series. Check whether the marked characteristic response time on the surrounding rock displacement time series occurs before the marked characteristic response time on the corresponding support stress response time series. If so, it is determined that it conforms to the physical time sequence logic that the change in the characteristic of the surrounding rock displacement occurs before the change in the characteristic of the support stress response. If all the monitored points being tested conform to the physical timing logic, then the data collected in this batch is determined to have time synchronization.

5. The method for synchronous monitoring of surrounding rock deformation and support structure deformation during tunnel construction as described in claim 4, characterized in that: The response mutation identification based on data difference is described in the following process: In the extracted time series data, the change amplitude between the current time data and the previous time data is calculated point by point starting from the base time. The real-time calculated change amplitude is compared with the mutation discrimination threshold within a time window starting from the reference time. If the calculated change amplitude at a certain moment within the time window exceeds the mutation discrimination threshold, a response mutation is identified.

6. The method for synchronous monitoring of surrounding rock deformation and support structure deformation during tunnel construction as described in claim 1, characterized in that: The priorities of daily synchronization verification and event-triggered supplementary verification in the hierarchical time synchronization verification are as follows: Routine synchronous verification serves as a regular verification method, while event-triggered supplementary verification serves as an occasional verification method, automatically triggered when a strong disturbance event occurs.

7. The method for synchronous monitoring of surrounding rock deformation and support structure deformation during tunnel construction as described in claim 3, characterized in that: The hierarchical time synchronization verification also includes fault early warning, which is implemented as follows: If the daily synchronous verification determines that a certain monitoring point pair has lost synchronization in daily data collection for multiple consecutive cycles, a fault warning will be triggered and the abnormal state will be recorded. When a strong disturbance event occurs later, an event-triggered supplementary verification will be automatically triggered for that point pair for review.

8. The method for synchronous monitoring of surrounding rock deformation and support structure deformation during tunnel construction as described in claim 1, characterized in that: The specific implementation process for analyzing the morphological characteristics and temporal relationship of the two curves is as follows: Plot the internal displacement-time curve of the surrounding rock and the support stress response-time curve for each monitoring point pair in the same coordinate system; The inflection points of the two curves are identified based on the change in the sign of the second derivative, and the timestamp of each inflection point is recorded. The inflection points of surrounding rock displacement and support stress response are paired according to their temporal proximity to construct a set of inflection point pairs; For each inflection point, calculate the lag time of the support stress response inflection point relative to the surrounding rock displacement inflection point, and compare this lag time with the preset physical reasonable response window; The proportion of inflection point pairs whose statistical lag time falls within a reasonable window to the total number of inflection point pairs is denoted as the proportion of collaborative inflection point pairs. Based on the identified inflection point locations, the two time curves are divided into several characteristic segments, including rising segments, falling segments, and stable segments. For characteristic segments of the same type in the displacement-time curve inside the surrounding rock and the support stress response-time curve, the segment-level overlap of the rising segment, falling segment and stable segment is obtained by calculating the ratio of the intersection length and union length of the two segments on the time axis.

9. The method for synchronous monitoring of surrounding rock deformation and support structure deformation during tunnel construction as described in claim 8, characterized in that: The process for determining whether the surrounding rock and support structure at this point are in a state of coordinated deformation or a state of coordinated abnormality is as follows: If a monitoring point meets the following conditions simultaneously, it is determined that the surrounding rock and the support structure at that point are in a state of coordinated deformation; otherwise, it is determined that they are in a state of coordinated abnormality. i) The proportion of collaborative inflection points reaches or exceeds the median proportion; ii) The overlap of segments in the rising, falling, and stable segments is greater than the consensus threshold.

10. The method for synchronous monitoring of surrounding rock deformation and support structure deformation during tunnel construction as described in claim 1, characterized in that: The triggering of the corresponding construction risk warning is as follows: The number of monitoring point pairs in a state of coordinated anomaly is counted among all monitoring point pairs; When a single monitoring point is in a state of coordinated anomaly, a local attention warning is triggered. When multiple monitoring point pairs within the same monitoring section, or corresponding monitoring point pairs between adjacent sections along the tunnel axis, are simultaneously in a coordinated abnormal state, a regional risk warning is triggered.

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