A monitoring control system and method for underpass tunnel construction

Abstract

The present invention relates to the technical field of stable control for the construction of underpass tunnels, and particularly relates to a monitoring and control system and method for the construction of underpass tunnels, including: constructing an underpass tunnel construction information model based on the construction design scheme and geological exploration data; characterizing the stress and deformation states of the underpass tunnel, the strata and existing structures, lifting mechanisms, and support units within its influence range according to the construction information model, identifying the control nodes for the balance of the system in the model, formulating a monitoring plan based on the control nodes, and feeding back the monitoring information to the construction information model; compared with the prior art, the beneficial effects of the present invention are: in the present invention, the underpass tunnel, strata, existing structures, etc. are regarded as a control system, and the deformation and stress information of the system objects are obtained through the monitoring and control system, the stable state of the system is identified, and corresponding control measures are timely adopted to maintain the deformation coordination and stress balance of the control system.

Description

Technical Field

[0001] The present invention relates to the technical field of construction stability control of underpass tunnels, and particularly relates to a monitoring and control system and method for underpass tunnel construction. Background Art

[0002] Underpass tunnels are usually used for underground passage of traffic or municipal facilities, which can effectively relieve the ground traffic pressure and do not occupy ground space. In recent years, with the development of urban traffic construction in China, the underground traffic network has become increasingly complex, and the situation of setting underpass tunnels under existing tunnel structures has also increased day by day. During the construction of underpass tunnels, there are buildings or structures on the ground, and there are also existing operating tunnels above the newly built tunnel. Therefore, relatively high requirements are imposed on the monitoring and control of ground deformation caused by construction.

[0003] In the preliminary preparation, through investigation and calculation, there is already a preliminary plan for the design of tunnel reinforcement and support structures. However, during the construction stage, when the deformation trend caused by soil unloading or different deformation and settlement conditions from those at the beginning of the design occur, at this time, the control of structural safety depends on the monitoring during construction, and control measures need to be taken according to the monitoring information. The accuracy of monitoring data and how to fully understand the stress and deformation trend of the tunnel structure through the monitoring data are required by the entire monitoring system. What kind of structural form to adopt to control the deformation convergence of the existing structure and the load overrun of the tunnel structure after obtaining the monitoring data are also issues that need to be considered during construction. There are many existing deformation control measures, such as strengthening temporary support, designing a jacking mechanism, etc. The jacking mechanism is installed between the underpass tunnel and the existing tunnel structure, and the deformation of the existing structure above the underpass tunnel is adjusted through the jacking force, so as to avoid the impact of the deformation of the upper structure on the safety of tunnel construction. Moreover, the reaction force generated during the jacking process acts on the construction tunnel and affects the support structure of the tunnel. How to systematically monitor the deformation of the underpass tunnel and the existing structure, and ensure the safety and stability of the support structure during the construction of the underpass tunnel while providing a jacking load to reduce the deformation trend is not involved in the existing underpass tunnel construction.

[0004] Therefore, developing a monitoring and control system and method for underpass tunnel construction not only has an urgent research value, but also has good economic benefits and industrial application potential, which is the driving force and foundation for the completion of the present invention. Summary of the Invention

[0005] In order to overcome the defects of the above-mentioned prior art pointed out, the inventor of the present invention has conducted in-depth research and completed the present invention after a large amount of creative labor.

[0006] Specifically, the present invention provides a monitoring and control system and method for underpass tunnel construction, which systematically monitors and feedbacks the deformation of existing structures, control loads and the stress of the support of the underpass tunnel during construction, and provides a technical basis for the stability of the support structure during tunnel construction.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A monitoring and control method for underpass tunnel construction, comprising:

[0009] Constructing an underpass tunnel construction information model based on the construction design scheme and geological exploration data;

[0010] Characterizing the stress and deformation states of the strata, existing structures, lifting mechanisms, and support units within the underpass tunnel and its influence range according to the construction information model, identifying the control nodes for the system balance in the model, formulating a monitoring plan based on the control nodes, and feeding back the monitoring information to the construction information model;

[0011] Determining the node control threshold for the engineering system balance and calibrating it in the data analysis module;

[0012] Laying out the monitoring components during the construction of the underpass tunnel in accordance with the construction information model;

[0013] Collecting the deformation and stress data of the strata, existing structures, lifting mechanisms, and support units within the underpass tunnel and its influence range, wherein the existing structures include underground pipelines, existing tunnels, existing buildings or structures;

[0014] Identifying the monitoring data of the control nodes, feedbacking and verifying the action range and bearing state of the lifting mechanism, and timely sending out a warning signal according to the system balance state.

[0015] In the present invention, as an improvement, the warning signal includes in-system warning and out-of-system warning;

[0016] (1) When the monitoring data of the strata and existing structures exceed the calibrated threshold but do not reach the bearing threshold of the lifting mechanism and support unit, the warning decision module sends out an in-system warning signal to control the lifting mechanism to provide a force to maintain the system stability;

[0017] (2) When the construction action system cannot self-balance or the deformation stress does not converge, the warning decision module sends out an out-of-system warning signal and calls the auxiliary measure strategy library to give a guiding plan.

[0018] In the present invention, as an improvement, the system balance is a relatively stable state in which the strata and existing structures within the underpass tunnel and its influence range can achieve self-balance.

[0019] In the present invention, as an improvement, the control threshold includes the maximum allowable force and deformation values of the strata and existing structures within the influence range of the underpass tunnel, the lifting mechanism, and the support unit.

[0020] In the present invention, as an improvement, the action range of the lifting mechanism is based on the system balance, and the action range of the lifting mechanism is calibrated by the controllable range of the deformation of the existing structure and the maximum force of the support unit.

[0021] In the present invention, as an improvement, determining the bearing state of the lifting mechanism includes:

[0022] By monitoring the component to feedback the deformation and stress data of the strata, existing structures, and support units within the influence range of the underpass tunnel construction;

[0023] Using the data analysis module to calibrate the loading data for the lifting mechanism to maintain the system balance, and to determine the bearing state of the lifting mechanism.

[0024] In the present invention, as an improvement, the force on the support unit includes the inherent surrounding rock pressure of the underpass tunnel and the reaction force of the lifting mechanism to maintain the system balance.

[0025] An underpass tunnel construction monitoring and control system includes:

[0026] A monitoring component, which monitors the stress and deformation states of the strata, existing structures, the lifting mechanism, and the support unit within the influence range of the underpass tunnel and its influence, and feeds the monitoring data back to the control platform, where the existing structures include underground pipelines, existing tunnels, existing buildings or structures;

[0027] A lifting mechanism, which is installed above the support unit of the underpass tunnel and below the existing structure to adjust the deformation of the structure above the underpass tunnel;

[0028] A support unit, which includes the support structure and auxiliary strengthening structure of the underpass tunnel, supports below the lifting mechanism, bears the reaction force of the lifting mechanism, and provides the basic bearing capacity for the lifting mechanism;

[0029] A control platform, which includes a data analysis module and an early warning decision-making module;

[0030] The data analysis module constructs a construction information model to represent the stress and displacement states of the existing structure, the lifting mechanism, and the support unit during the construction of the underpass tunnel, analyzes the control nodes for the balance of the construction information model system, determines the action range and bearing state of the lifting mechanism through monitoring feedback verification, and obtains the deformation and stress data signals collected by the monitoring component;

[0031] The early warning decision-making module extracts the auxiliary measure strategy library, identifies the stability state of the control nodes, issues an early warning signal based on the unstable state of the underpass tunnel construction system, recommends construction auxiliary measures, and guides engineering reinforcement.

[0032] In the present invention, as an improvement, the monitoring component includes displacement monitoring instruments disposed at the formation, underground pipelines, existing tunnels, existing buildings or structures, and mechanical monitoring sensors installed between the lifting mechanism and the support unit.

[0033] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0034] (1) In the present invention, the undercrossing tunnel, formation, existing structure, etc. are regarded as a control system. By the monitoring and control system, the deformation and stress information of the system object is obtained, the stability state of the system is identified, and corresponding control measures are timely adopted to maintain the deformation coordination and stress balance of the control system.

[0035] (2) In the present invention, the monitoring and control platform monitors the deformation and stress states of each object in the system, identifies the unstable factors in the construction of the undercrossing tunnel, timely issues early warning information, guides the reasonable selection of control measures, and forms a systematic control method of monitoring - feedback - response, providing guarantee for safe construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to actual scale.

[0037] Figure 1 Schematic diagram of the structural position relationship of each component of the monitoring and control system of the present invention;

[0038] Figure 2 Schematic diagram of the flow of the monitoring and control method of the present invention;

[0039] In the figure, 1, undercrossing tunnel; 2, lifting component; 3, existing tunnel; 4, underground pipeline; 5, formation; 6, existing building or structure. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0040] The following will describe in detail the embodiments of the technical solutions of the present invention with reference to the drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention, and thus are only examples and cannot be used to limit the protection scope of the present invention.

[0041] An undercrossing tunnel construction monitoring and control system, which while monitoring the deformation of the existing structure, combines the monitoring data analysis and control platform to realize data feedback and give control measures.

[0042] As Figure 1 shown, the monitoring and control system specifically includes:

[0043] A monitoring component that monitors the stress and deformation states of the strata, existing structures, lifting mechanism, and support unit within the underpass tunnel and its affected area, and feeds back the monitoring data to the control platform;

[0044] The existing structures include underground pipelines 4, existing tunnels 3, and existing buildings or structures 6;

[0045] A lifting mechanism installed above the support unit of the underpass tunnel and below the existing structure, with a lifting component 2 for adjusting the deformation of the structure above the underpass tunnel. The lifting component 2 is telescopic and can specifically be a hydraulic self-locking jack or a lifting airbag;

[0046] A support unit, including the support structure and auxiliary strengthening structure of the underpass tunnel, supports below the lifting mechanism, bears the reverse force of the lifting mechanism, and provides the basic bearing capacity for the lifting mechanism;

[0047] The control platform includes a data analysis module and an early warning decision-making module,

[0048] The data analysis module includes a processing system, a data receiving unit, and a data sending unit. Among them, the processing system has the function of constructing a construction information model, which characterizes the strata and existing structures within the underpass tunnel and the upper affected area. The data receiving unit acquires the deformation and stress data signals collected by the monitoring component and transmits the signals to the processing system, which characterizes the stress and displacement states of the existing structures, lifting mechanism, and support unit during the construction process of the underpass tunnel in the construction information model, analyzes the balance control nodes of the construction information model system, and determines the action range and bearing state of the lifting mechanism through monitoring feedback verification;

[0049] An early warning decision-making module that identifies the stable state of the control node, issues an early warning signal based on the unstable state of the underpass tunnel construction system, and feeds it back to the display terminal;

[0050] The early warning decision-making module can call the auxiliary measure strategy library, select construction auxiliary measures that match the data information, and guide engineering reinforcement. The auxiliary measure strategy library is pre-constructed based on historical engineering data.

[0051] The monitoring component includes displacement and stress monitoring instruments set at the strata 5, underground pipelines 4, existing tunnel 3 structures, and existing buildings or structures 6, as well as displacement and mechanical sensors installed between the lifting mechanism and the support unit. Mechanical and displacement sensors are set at the support structure to monitor the deformation and stress of the support structure.

[0052] System balance is a relatively stable state in which the strata and existing structures within the underpass tunnel and its affected area can achieve self-balance.

[0053] The monitored deformation data includes, but is not limited to, soil deformation, existing tunnel deformation, existing building or structure deformation, and pipeline deformation.

[0054] The jacking load provided by the lifting mechanism and the reverse load acting on the support unit are measured by mechanical sensors installed at the support unit and the lifting mechanism, and the measured values are transmitted to the control platform for the control platform to analyze the load change.

[0055] The support unit is the primary support arch of the undercrossing tunnel, and the lifting mechanism is installed on the top of the primary support arch. The upper end of the lifting mechanism fits the bottom concrete layer of the existing tunnel or the auxiliary support steel frame and the underpinning steel frame.

[0056] As Figure 2 shown, a construction monitoring and control method for an undercrossing tunnel applying the above control system includes:

[0057] Construct an undercrossing tunnel construction information model based on the construction design scheme and geological exploration data. The geological exploration data includes the formation, underground pipelines, existing tunnel structure, and the location, structure, and stress information of existing buildings or structures. The undercrossing tunnel construction information model includes the undercrossing tunnel construction information and the geological exploration data within the influence range of the undercrossing tunnel;

[0058] Characterize the stress and deformation states of the formation, existing structures, lifting mechanism, and support unit within the undercrossing tunnel and its influence range according to the construction information model, identify the control nodes for system balance in the model, formulate a monitoring plan based on the control nodes, and feedback the monitoring information to the construction information model;

[0059] Determine the node control threshold for the engineering system balance and calibrate it in the data analysis module;

[0060] Layout the monitoring components during the construction of the undercrossing tunnel in accordance with the construction information model;

[0061] Collect the deformation and stress data of the formation, existing structures, lifting mechanism, and support unit within the undercrossing tunnel and its influence range. Among them, the existing structures include underground pipelines, existing tunnels, existing buildings or structures;

[0062] Identify the monitoring data of the control nodes, feedback and verify the action range and bearing state of the lifting mechanism, and issue a warning signal in a timely manner according to the system balance state.

[0063] The action range of the lifting mechanism is based on system balance. By providing a jacking load, it curbs the deformation trend of the existing structure, and at the same time acts on the support unit with a reverse load. The action range of the lifting mechanism is calibrated with the controllable range of the existing structure deformation and the maximum stress of the support unit.

[0064] Determining the bearing state of the lifting mechanism includes:

[0065] The monitoring component feeds back the deformation data of the existing structures and the force data of the support units within the influence range of the construction of the underpass tunnel;

[0066] The data analysis module calibrates the loading data in which the lifting mechanism acts between the two and maintains the structural force balance;

[0067] Based on the deformation data of the existing structures, the loading data and the force data of the support units, the bearing state of the lifting mechanism is judged.

[0068] Among them, the conditions for judging the stability of the support structure include geological conditions, the size of the support section and the support materials.

[0069] The control thresholds include the maximum allowable forces and deformation values of the strata, the existing structures, the lifting mechanism and the support units within the underpass tunnel and its influence range.

[0070] Stress and displacement sensors are arranged at the middle of the crown, the two side waists and the two arch bottoms of the support structure to monitor the force and deformation of the support structure. Through the monitoring of the crown, the waist and the arch bottom of the support structure, the force and deformation trends of the support structure are clarified, providing a basis for the adjustment of the lifting mechanism and the deformation of the existing structures.

[0071] In the early warning decision-making, the judgment standard for the stability of the support structure involves the structural safety factor, and the safety factor of the support structure is judged by its deformation and the permanent load, the basic variable load and other variable loads it bears.

[0072] The early warning signals include in-system early warning and out-of-system early warning;

[0073] (1) When the monitoring data of the strata and the existing structures exceed the calibration threshold but do not reach the bearing threshold of the lifting mechanism and the support units, the early warning decision-making module issues an in-system early warning signal to control the lifting mechanism to provide a force to maintain the system stability;

[0074] (2) When the construction action system cannot achieve self-balance or the deformation and force do not converge, the early warning decision-making module issues an out-of-system early warning signal and calls the auxiliary measure strategy library to give a guiding plan.

[0075] When the support structure produces elastic deformation but does not reach the force threshold, the force and deformation of the support structure are monitored in real time. At the same time, the bearing capacity of the support structure on the lifting mechanism is calculated, and the change of the bearing capacity is judged until the support structure returns to a stable state;

[0076] When the force on the support structure exceeds the threshold or the action range of the lifting mechanism exceeds the lifting threshold, an out-of-system early warning is issued, and the deformation of the existing structure above the underpass tunnel is controlled in combination with appropriate auxiliary control measures. Among them, the auxiliary control measures include grouting, strong support, etc.

[0077] Embodiment 1:

[0078] The underpass tunnel of a certain station is located below the existing tunnel and is constructed using the "PBA" pilot tunnel method. The cross-sectional form of the pilot tunnel is divided into a flat-top section and an arched section. Among them, the flat-top section closely passes under the bottom plate of a municipal tunnel, and the overburden above the arched section is about 9.45 m.

[0079] To ensure the operation safety of the existing tunnel, during construction, control objects within the monitoring influence range are monitored, and an automatic synchronous jacking compensation system is adopted to ensure the stability of the control system.

[0080] Based on the system balance as the control basis, system balance control nodes are obtained, and monitoring components are arranged at the control nodes. The specific burial of the monitoring components is shown in Table 1:

[0081] Table 1 Burial of Monitoring Components

[0082] Monitoring Items Designed Measuring Points (pcs) Installation Location Installation Time Surface Deformation 23 At the Surface above the Tunnel Before Tunnel Excavation Deformation of the Pier of the Overhead Building 10 At the Bottom of the Pier Before the Construction of the Retaining Piles Pipeline Settlement 46 At the Buried Pipeline above the Tunnel Before Tunnel Excavation Deformation of the Existing Tunnel 60 Below the Existing Tunnel Before Tunnel Excavation Deformation of the Under - passing Tunnel 9 Inside the Under - passing Tunnel After Tunnel Excavation

[0083] Install 150t hydraulic self-locking jacks at the top of the arch frame of the pilot tunnel. After installing the arch frame, use an automatic monitoring and control platform to synchronously monitor and jack, with 24-hour all-weather monitoring. A total of 68 groups and 136 jacks are set for the 4 pilot tunnels.

[0084] Strengthen the primary support arch frame within the range of the underpass tunnel. Set 1 section of steel section arch frame every 2 sections of grid steel arch frames longitudinally. The primary support arch frames at the bottom of the side walls of the tunnel are closely arranged. Install and debug the jacks. According to the deformation control range less than 1 mm, pre-press the jacks, mark the changes in the monitoring data of each control node, and complete the debugging of the jacks.

[0085] The data analysis module obtains the monitoring data in real time, calibrates the data with the constructed system model, and analyzes it to obtain whether the monitoring data meets the requirements of system balance. As the construction progresses, if the system balance meets the requirements, continuous monitoring is carried out. The specific control thresholds of the monitoring data are shown in Table 2:

[0086] Table 2 Control Thresholds of Monitoring Data

[0087] Monitoring Items Single - time (mm) Cumulative (mm) Surface Deformation ±5 ±25 Pipeline Settlement (Water Supply and Drainage Pipeline / Gas Pipeline) ±5 / ±3 ±20 Pier Settlement ±2 ±20 Deformation of the Crown of the Initial Support ±5 ±30 Deformation of the Existing Tunnel ±2 ±15 Vertical Displacement of the Pile Top ±3 ±20 Horizontal Displacement of the Pile Top ±3 ±20

[0088] From the excavation of the pilot tunnel to the completion of the construction of the second lining roof slab, the control thresholds and cumulative changes of the monitoring data are shown in Table 3:

[0089] Table 3 Control Thresholds and Cumulative Changes of Monitoring Data

[0090] Monitoring Items Single - time Deformation Control Value (mm) Cumulative Deformation Control Value (mm) Cumulative Change Value (mm) Surface Deformation ±5 ±25 -18.58 Pipeline Settlement (Water Supply and Drainage Pipeline / Gas Pipeline) ±5 / ±3 ±20 -14.60 Pier Settlement ±2 ±20 -7.81 Deformation of the Crown of the Initial Support ±5 ±30 -8.1 Deformation of the Existing Tunnel ±2 ±15 -9.9 Vertical Displacement of the Pile Top ±3 ±20 -2.1 Horizontal Displacement of the Pile Top ±3 ±20 -4.9

[0091] The data analysis module calibrates the monitoring threshold into the information model and determines whether the data change is within the threshold range. When the data change exceeds the calibration threshold but does not reach the load threshold of the lifting mechanism and the support unit, the early warning decision module sends out an early warning signal within the system and drives the lifting mechanism to synchronously lift and compensate, monitors the data changes, and locks the lifting mechanism position after reaching the control value.

[0092] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and specification of the present invention.

Claims

1. A method for monitoring and controlling underpass tunnel construction, characterized in that: include: Construct an underpass tunnel construction information model based on the construction design plan and geological survey data; Characterize the stress and deformation state of the underground tunnel and the strata and existing structures, lifting mechanisms, and support units within its influence range based on the construction information model, identify the control nodes of the system balance in the model, formulate a monitoring plan based on the control nodes, and feed the monitoring information back to the construction information model; Determine the node control threshold of the engineering system balance and calibrate it in the data analysis module; Deploy monitoring components during the tunnel construction process according to the construction information model; Collect deformation and force data of the strata and existing structures, lifting mechanisms, and support units under the tunnel and within its influence range, where the existing structures include underground pipelines, existing tunnels, and existing buildings or structures; Identify the monitoring data of the control node, feedback and verify the action range and load-bearing status of the lifting mechanism, and issue early warning signals in a timely manner according to the balance status of the system; System balance means that the strata and existing structures under the tunnel and within its influence range can achieve a relatively stable state of self-balance; Determining the load-bearing state of the lifting mechanism includes: The monitoring components provide feedback on the deformation and stress data of the strata, existing structures and support units within the scope of the underpass construction; The data analysis module is used to calibrate the loading data of the lifting mechanism to maintain the system balance and to determine the load-bearing state of the lifting mechanism; Early warning signals include internal and external warnings. (1) When the monitoring data of the local layer and existing structure exceeds the calibration threshold but does not reach the load threshold of the lifting mechanism and support unit, the early warning decision module sends out an internal early warning signal to control the lifting mechanism to provide force to maintain the stability of the system; (2) When the construction action system cannot balance itself or the deformation force does not converge, the early warning decision module sends out an external early warning signal and calls the auxiliary measures strategy library to provide guidance plans; The support unit is a primary support arch frame passing through the tunnel, and the lifting mechanism is installed on the top of the primary support arch frame. The upper end of the lifting mechanism is in contact with the bottom concrete layer of the existing tunnel or the auxiliary support steel frame and the underpinning steel frame.

2. The underpass construction monitoring and control method according to claim 1 is characterized in that: The control thresholds include the maximum allowable stress and deformation values ​​of the strata and existing structures, lifting mechanisms, and support units within the underpass and its influence range.

3. The underpass construction monitoring and control method according to claim 1 is characterized in that: The range of motion of the lifting mechanism is based on the balance of the system and is calibrated by the controllable range of deformation of the existing structure and the maximum force of the support unit.

4. The underpass construction monitoring and control method according to claim 1 is characterized in that: The forces acting on the support unit include the inherent surrounding rock pressure of the tunnel and the reverse force of the lifting mechanism to maintain the balance of the system.

5. A monitoring and control system for the underpass construction monitoring and control method according to claim 1, characterized in that: include: Monitoring components monitor the stress and deformation status of the strata and existing structures, lifting mechanisms, and support units within the tunnel and its influence range, and feed back the monitoring data to the control platform, where the existing structures include underground pipelines, existing tunnels, and existing buildings or structures; The lifting mechanism is installed above the support unit of the underpass tunnel and below the existing structure to adjust the deformation of the structure above the underpass tunnel; The support unit includes a support structure and an auxiliary reinforcement structure for the underpass tunnel, which is supported below the lifting mechanism, bears the reverse force of the lifting mechanism, and provides basic bearing capacity for the lifting mechanism; Control platform, including data analysis module and early warning decision module; The data analysis module builds a construction information model to characterize the stress and displacement status of the existing structure, lifting mechanism and support unit during the construction of the underpass tunnel, analyzes the control nodes of the construction information model system balance, determines the lifting mechanism movement range and load-bearing status through monitoring feedback verification, and obtains the deformation and stress data signals collected by the monitoring components; The early warning decision-making module extracts the auxiliary measures strategy library, identifies the stable state of the control node, issues early warning signals based on the instability of the underpass construction system, recommends construction auxiliary measures, and guides engineering reinforcement.

6. The underpass construction monitoring and control system according to claim 5 is characterized in that: The monitoring components include displacement monitoring instruments installed in the ground, underground pipelines, existing tunnels, existing buildings or structures, and mechanical sensors installed between lifting mechanisms and support units.

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