Underpass tunnel construction monitoring control system and method

Abstract

The invention relates to the technical field of under-crossing tunnel construction stability control, in particular to an under-crossing tunnel construction monitoring control system and method, and the method comprises the steps: constructing an under-crossing tunnel construction information model based on a construction design scheme and geological exploration data; according to the construction information model, representing the stress and deformation states of the underpass tunnel, the stratum in the influence range of the underpass tunnel, the existing structure, the lifting mechanism and the supporting unit, identifying control nodes of system balance in the model, making a monitoring scheme based on the control nodes, and feeding back monitoring information to the construction information model; compared with the prior art, the method has the advantages that an underpass tunnel, a stratum, an existing structure and the like serve as a control system, deformation and stress information of a system object is obtained by monitoring the control system, the stable state of the system is judged, and corresponding control measures are adopted in time to maintain deformation coordination and stress balance of the control system.

Description

Technical Field

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

[0002] Underpass tunnels are usually used for underground passage of transportation or municipal facilities, which can effectively alleviate the pressure of ground traffic and do not occupy ground space. In recent years, with the development of urban transportation construction in my country, the underground transportation network has become increasingly complex, and the number of underpass tunnels set up under existing tunnel structures has also increased. During the construction of underpass tunnels, there are buildings or structures on the ground, and there are existing tunnels in operation above the new tunnels. Therefore, the monitoring and control requirements for ground deformation caused by construction are relatively high.

[0003] In the early preparation, through investigation and calculation, a preliminary plan for the design of tunnel reinforcement and support structure has been prepared. However, during the construction stage, due to the deformation trend caused by soil unloading or the deformation and settlement conditions different from those at the beginning of the design, 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 the monitoring data and how to fully understand the stress deformation trend of the tunnel structure through the monitoring data are required by the entire monitoring system. What kind of structural form should be used to control the deformation convergence of the existing structure and the overload 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 and designing jacking mechanisms. The jacking mechanism is installed between the underpass tunnel and the existing tunnel structure. The deformation of the existing structure above the underpass tunnel is adjusted by the jacking force, thereby avoiding the impact of the deformation of the upper structure on the safety of the tunnel construction. The reaction force generated during the jacking process acts on the construction tunnel and affects the tunnel support structure. How to systematically monitor the deformation of the underpass tunnel and the existing structure, and provide jacking loads to reduce the deformation trend while ensuring the safety and stability of the support structure during the underpass tunnel construction, has not been involved in the existing underpass tunnel construction.

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

[0005] In order to overcome the above-mentioned defects of the prior art, the inventors conducted in-depth research and completed the present invention after paying a lot of creative work.

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

[0007] To achieve the above object, the present invention provides the following technical solutions: A method for monitoring and controlling underpass tunnel construction, comprising: 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 strata and existing structures, lifting mechanisms, and support units within the tunnel and 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 within the tunnel and 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 system balance status.

[0008] In the present invention, as an improvement, the warning signal includes an internal warning and an external warning; (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.

[0009] In the present invention, as an improvement, the system balance is a relatively stable state in which the underground tunnel and the strata and existing structures within its influence range can achieve self-balance.

[0010] In the present invention, as an improvement, the control threshold value includes the maximum allowable stress and deformation value of the underpass tunnel and the strata and existing structures, lifting mechanisms, and support units within its influence range.

[0011] 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 existing structural deformation and the maximum force of the support unit.

[0012] In the present invention, as an improvement, 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 status of the lifting mechanism.

[0013] In the present invention, as an improvement, the force on the support unit includes the inherent surrounding rock pressure of the tunnel passing through and the reverse force of the lifting mechanism to maintain the balance of the system.

[0014] A monitoring and control system for underpass tunnel construction, comprising: 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.

[0015] In the present invention, as an improvement, the monitoring assembly includes a displacement monitoring instrument arranged at a stratum, underground pipeline, existing tunnel, existing building or structure, and a mechanical monitoring sensor installed between a lifting mechanism and a supporting unit.

[0016] Compared with the prior art, the present invention has the following beneficial effects: (1) In the present invention, the underpass, stratum, existing structure, etc. are regarded as a control system. The deformation and force 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 adopted in a timely manner to maintain the deformation coordination and force balance of the control system.

[0017] (2) In the present invention, the monitoring and control platform monitors the deformation and stress state of each object in the system, identifies unstable factors in the underpass tunnel construction, issues early warning information in a timely manner, guides the rational selection of control measures, and forms a systematic control method of monitoring-feedback-response to provide guarantee for safe construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for the specific embodiments or the description of 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 according to the actual scale.

[0019] Figure 1 This is a schematic diagram of the structural position relationship of each component of the monitoring and control system of the present invention; Figure 2 It is a flow chart of the monitoring and control method of the present invention; In the figure, 1. underpass, 2. lifting components, 3. existing tunnel, 4. underground pipelines, 5. strata, 6. existing buildings or structures. DETAILED DESCRIPTION

[0020] The following embodiments of the technical solution of the present invention are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and are therefore only used as examples, and cannot be used to limit the protection scope of the present invention.

[0021] A monitoring and control system for underpass tunnel construction, which monitors the deformation of existing structures and combines a monitoring data analysis control platform to realize data feedback and give control measures.

[0022] like Figure 1 As shown, the monitoring and control system specifically includes: 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 the monitoring data back to the control platform; Existing structures include underground pipelines 4, existing tunnels 3, and existing buildings or structures 6; The lifting mechanism is installed above the underpass tunnel support unit and is located below the existing structure. It has a lifting component 2 for adjusting the deformation of the structure above the underpass tunnel. The lifting component 2 is telescopic and can be a hydraulic self-locking jack or a lifting airbag. 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; The control platform includes data analysis module and early warning decision module. The data analysis module includes a processing system, a data receiving unit and a data sending unit, wherein the processing system has the function of constructing a construction information model, the construction information model represents the strata and existing structures in the underpass tunnel and the upper impact area, the data receiving unit obtains the deformation and force data signals collected by the monitoring component, and transmits the signals to the processing system, represents the force and displacement states of the existing structures, lifting mechanisms and support units during the construction 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 load-bearing state of the lifting mechanism through monitoring feedback verification; The early warning decision module identifies the stable state of the control node, issues an early warning signal based on the instability of the underpass construction system, and feeds back to the display terminal; The early warning decision-making module can call the auxiliary measures strategy library, select construction auxiliary measures that match the data information, and guide project reinforcement. The auxiliary measures strategy library is pre-built based on historical engineering data.

[0023] The monitoring components include displacement and stress monitoring instruments installed at the stratum 5, underground pipelines 4, existing tunnel 3 structures, existing buildings or structures 6, and displacement and mechanical sensors installed between the lifting mechanism and the supporting unit. Mechanical and displacement sensors are installed at the supporting structure to monitor the deformation and stress of the supporting structure.

[0024] System balance refers to a relatively stable state in which the strata and existing structures under the tunnel and within its influence range can achieve self-balance.

[0025] The monitored deformation data include but are not limited to soil deformation, deformation of existing tunnels, deformation of existing buildings or structures, and deformation of pipelines.

[0026] The lifting 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. The measured values ​​are transmitted to the control platform, which analyzes the load changes.

[0027] 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.

[0028] like Figure 2 As shown, a method for monitoring and controlling the construction of an underpass tunnel using the above control system comprises: The construction information model of the underpass tunnel is constructed based on the construction design plan and geological survey data. The geological survey data includes the position, structure and force information of the strata, underground pipelines, existing tunnel structures and existing buildings or structures. The underpass tunnel construction information model includes the underpass tunnel construction information and the geological survey data within the influence range of the underpass tunnel. Characterize the stress and deformation state of the strata and existing structures, lifting mechanisms, and support units within the tunnel and 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 within the tunnel and 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 system balance status.

[0029] The action range of the lifting mechanism is based on the balance of the system. It curbs the deformation trend of the existing structure by providing a jacking load and acts on the reverse load of the support unit at the same time. The action range of the lifting mechanism is calibrated by the controllable range of deformation of the existing structure and the maximum force of the support unit.

[0030] Determining the load-bearing state of the lifting mechanism includes: The monitoring components provide feedback on deformation data of existing structures and stress data of support units within the influence range of underpass construction; The data analysis module is used to calibrate the loading data of the lifting mechanism acting between the two and maintaining the force balance of the structure; The load-bearing state of the lifting mechanism is determined by the existing structural deformation data, loading data and support unit force data.

[0031] Among them, the conditions for judging the stability of the support structure include geological conditions, support section dimensions and support materials.

[0032] 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.

[0033] Stress and displacement sensors are installed in the middle of the arch, the waists on both sides and the bottom of the arch on both sides of the supporting structure to monitor the stress and deformation of the supporting structure. By monitoring the arch, waist and bottom of the supporting structure, the stress and deformation trend of the supporting structure can be clarified, providing a basis for the adjustment of the lifting mechanism and the deformation of the existing structure.

[0034] In the early warning decision, the judgment criteria for the stability of the support structure involve the structural safety factor. The safety factor of the support structure is determined by its deformation and the permanent load, basic variable load and other variable loads it is subjected to.

[0035] 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.

[0036] When the support structure produces elastic deformation but does not reach the stress threshold, the stress 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 in bearing capacity is determined until the support structure returns to a stable state; When the stress on the support structure exceeds the threshold or the movement range of the lifting mechanism exceeds the lifting threshold, an external warning is issued, and the deformation of the existing structure above the underpass is controlled in combination with appropriate auxiliary control measures. Among them, auxiliary control measures include grouting, strong support, etc.

[0037] Embodiment 1: The underpass tunnel of a certain station is located below the existing tunnel and is constructed using the "PBA" pilot tunnel method. The cross-section of the pilot tunnel is divided into a flat-top section and an arched section. The flat-top section is closely attached to the bottom slab of a municipal tunnel passing underneath, and the top of the arched section is covered with soil of about 9.45m.

[0038] To ensure the operational safety of existing tunnels, during construction, the controlled objects within the impact range are monitored, and an automatic synchronous jacking compensation system is adopted to ensure the stability of the control system.

[0039] Taking system balance as the control basis, the system balance control node is obtained, and monitoring components are deployed at the control node. The specific deployment of monitoring components is shown in Table 1: Table 1 Monitoring component buried Monitoring Project Design measurement points Buried location Buried time Surface deformation 23 On the surface above the tunnel Before tunnel excavation Deformation of bridge piers on the ground 10 Bottom of bridge pier Before retaining pile construction Pipeline settlement 46 Pipeline buried above the tunnel Before tunnel excavation Deformation of existing tunnels 60 Under the existing tunnel Before tunnel excavation Deformation of the underpass tunnel 9 Under the tunnel After tunnel excavation A 150t hydraulic self-locking jack is installed on the top of the pilot tunnel arch. After the arch is buried, an automatic monitoring and control platform is used to synchronously monitor the jacking, with 24-hour all-weather monitoring. A total of 68 groups and 136 jacks are set up in the four pilot tunnels.

[0040] The initial arch frame in the underpass area is strengthened, and one steel frame is set every two grid steel frames in the longitudinal direction. The initial arch frames at the bottom of the tunnel side wall are densely arranged. The jacks are installed and debugged. According to the deformation control range of less than 1mm, the jacks are pre-pressurized, and the changes in monitoring data of each control node are marked to complete the jack debugging.

[0041] The data analysis module obtains monitoring data in real time, calibrates the data with the constructed system model, and analyzes it to determine whether the monitoring data meets the system balance requirements. As the construction progresses, if the system balance meets the requirements, continuous monitoring is performed. The specific monitoring data control thresholds are shown in Table 2: Table 2 Monitoring data control thresholds Monitoring Project Single (mm) Cumulative (mm) Surface deformation ±5 ±25 Pipeline settlement (water supply and drainage pipeline / gas pipeline) ±5 / ±3 ±20 Pier settlement ±2 ±20 Initial support arch deformation ±5 ±30 Deformation of existing tunnels ±2 ±15 Vertical displacement of pile top ±3 ±20 Horizontal displacement of pile top ±3 ±20 From the excavation of the pilot tunnel to the completion of the construction of the secondary lining top plate, the control thresholds and cumulative changes of various monitoring data are shown in Table 3: Table 3 Monitoring data control thresholds and cumulative changes Monitoring Project Single 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 Initial support arch deformation ±5 ±30 -8.1 Deformation of existing tunnels ±2 ±15 -9.9 Vertical displacement of pile top ±3 ±20 -2.1 Horizontal displacement of pile top ±3 ±20 -4.9 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.

[0042] 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 strata and existing structures, lifting mechanisms, and support units within the tunnel and 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 within the tunnel and 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 system balance status.

2. The underpass construction monitoring and control method according to claim 1 is characterized in that: 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.

3. The underpass construction monitoring and control method according to claim 1 is characterized in that: System balance refers to a relatively stable state in which the strata and existing structures under the tunnel and within its influence range can achieve self-balance.

4. The method for monitoring and controlling the construction of an underpass tunnel according to claim 1, 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.

5. 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.

6. The underpass construction monitoring and control method according to claim 3 is characterized in that: 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 status of the lifting mechanism.

7. The underpass construction monitoring and control method according to claim 3 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.

8. A monitoring and control system for underpass tunnel construction, 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 underpass tunnel support unit 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.

9. The underpass construction monitoring and control system according to claim 8 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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