Pressure on-line monitoring system and method for reinforced concrete filling retaining wall of underground stope

Abstract

The invention discloses a pressure online monitoring system and method for a reinforced concrete filling retaining wall of an underground stope, and belongs to the field of mine filling and geotechnical engineering safety monitoring. The invention provides an integrated pre-embedded monitoring system for solving the problems that in the prior art, the stress state of a retaining wall cannot be obtained in real time, a sensor is prone to being damaged and falling off, and monitoring data is unstable. The system comprises a pre-embedded assembly which comprises a pre-embedded fixing plate, a pre-embedded mounting base and a pre-embedded cable conduit and is pre-embedded in a reinforcing mesh before a retaining wall is poured; the pressure sensing unit is detachably fixed in the embedded mounting base and used for sensing the pressure borne by the retaining wall; the data acquisition and transmission module is connected with the pressure sensing unit through a pre-embedded cable conduit; and the data processing and stability judging module is used for calculating a safety coefficient on the basis of the received pressure data in combination with the retaining wall structure parameters. According to the invention, rigid coupling of the sensor and the reinforced concrete structure is realized, and stability of long-term monitoring and authenticity of data are ensured.

Description

Online pressure monitoring system and method for reinforced concrete retaining walls in underground mining areas Technical Field

[0001] This invention relates to the field of mine backfilling and geotechnical engineering safety monitoring technology, and in particular to an online pressure monitoring system and method for reinforced concrete backfill retaining walls in underground mining areas. Background Technology

[0002] In underground metal mining, techniques such as the approach-type upward layered filling method and the staged open-stope subsequent filling method are widely used. In these techniques, reinforced concrete filling retaining walls need to be constructed at the entrance of the stope roadway. Their main function is to temporarily block highly fluid filling slurry (such as tailings slurry, paste, etc.), providing a closed space for the filling material to solidify and harden. They are key load-bearing structures that ensure the stability of the stope.

[0003] The stress conditions of the backfill retaining wall are complex throughout its service life, mainly bearing: the hydrostatic pressure of the backfill slurry; the impact pressure generated at the moment of filling; the lateral expansion pressure during the cementation and hardening process of the backfill; and long-term loads caused by temperature stress and self-weight settlement. Once the retaining wall is damaged, it will cause serious slurry leakage and slurry flushing accidents, leading to roadway blockage, equipment damage, and even threatening the safety of workers. It is one of the most important safety risks in backfilled mining areas.

[0004] Current technologies for monitoring infill retaining walls are relatively scarce and have many shortcomings. First, there is a lack of real-time online monitoring technology specifically targeting the stress state of reinforced concrete retaining walls; most methods rely on manual inspection and experience-based judgment. Second, some experimental monitoring schemes often directly attach pressure sensors to the retaining wall formwork or concrete surface. This installation method is highly susceptible to being washed away by flowing concrete or filling slurry during pouring, leading to sensor failure. Furthermore, the sensors are directly exposed to the harsh underground environment without effective protection, and their signal cables are easily damaged during construction or subsequent deformation, compromising the stability and long-term reliability of the monitoring data. In addition, existing monitoring methods fail to effectively correlate the measured pressure data with the load-bearing capacity (such as bending and shear resistance) of the reinforced concrete retaining wall itself, failing to form a complete "real-time pressure-load-safety factor-early warning" chain, making it difficult to achieve truly meaningful online safety early warning.

[0005] Therefore, there is an urgent need for an online pressure monitoring system and method that can be integrated with the reinforced concrete retaining wall body to ensure that the sensor is firmly installed and works stably for a long time, and can combine the monitoring data with the structural bearing capacity for online safety assessment. Summary of the Invention

[0006] The purpose of this invention is to provide an online pressure monitoring system and method for reinforced concrete retaining walls in underground mining areas, in order to solve the problems existing in the prior art.

[0007] To achieve the above objectives, the present invention provides an online pressure monitoring system for reinforced concrete retaining walls in underground mining areas, comprising: a pre-embedded component, the pre-embedded component including a pre-embedded fixing plate, a pre-embedded mounting base, and a pre-embedded cable conduit, for fixed connection with the steel mesh of the retaining wall before the retaining wall is poured; at least one pressure sensing unit, detachably installed in the pre-embedded mounting base, for sensing the pressure on the retaining wall and generating a pressure signal; a data acquisition and transmission module, located underground and connected to the pressure sensing unit through the pre-embedded cable conduit, for acquiring and transmitting the pressure signal; and a data processing and stability assessment module, communicatively connected to the data acquisition and transmission module, for receiving the pressure signal and calculating a real-time safety factor based on the bearing capacity model of the retaining wall.

[0008] Preferably, the embedded fixing plate is a plate-shaped structure with a central hollow core, and the two ends of the embedded fixing plate are provided with fixing steel bars for anchoring into the surrounding rock. The plate surface of the embedded fixing plate is provided with bolt holes for connecting to the embedded mounting base.

[0009] Preferably, the pre-embedded mounting base is a shell structure with one open side, and the periphery of the opening is provided with fixing wings for connecting with the pre-embedded fixing plate. The interior of the shell structure is provided with fixing bolts for fixing the pressure sensing unit.

[0010] Preferably, the pressure sensing unit includes: a pressure sensor body; a pressure equalization transmission layer disposed on the outside of the pressure sensing surface of the pressure sensor body for uniformly transmitting external pressure; and a protective shell disposed on the outside of the pressure equalization transmission layer and fixedly connected to the pre-embedded mounting base, wherein the protective shell has multiple grouting holes.

[0011] Preferably, the pressure equalization and transmission layer comprises a rubber pad and a stainless steel sheet stacked sequentially, with the rubber pad disposed close to the pressure sensor body.

[0012] Preferably, the protective shell is further provided with a rubber sealing sleeve for sealing the cable interface on the side facing away from the filling body.

[0013] Preferably, the pre-embedded cable conduit is made of metal or high-strength plastic and is pre-embedded inside the retaining wall to provide an independent protective channel for the cable connecting the pressure sensing unit and the data acquisition and transmission module.

[0014] Preferably, the data processing and stability assessment module includes: a data processing unit for filtering and correcting the received pressure signal and reconstructing the pressure distribution on the retaining wall surface; a bearing capacity calculation unit for storing and retrieving the ultimate bearing capacity parameters of the retaining wall; a safety factor calculation unit for calculating the safety factor of the retaining wall in real time based on the pressure distribution and the ultimate bearing capacity parameters; and an early warning unit for issuing an alarm signal when the safety factor is lower than a preset threshold.

[0015] This invention also provides an online monitoring method for the pressure of a reinforced concrete retaining wall in an underground mining area based on the aforementioned system, comprising the following steps: S1: Before pouring the retaining wall, fixing the pre-embedded assembly consisting of a pre-embedded fixing plate, a pre-embedded mounting base, and a pre-embedded cable conduit to the retaining wall reinforcement mesh; S2: Installing and fixing the pressure sensing unit in the pre-embedded mounting base, and leading the cable out through the pre-embedded cable conduit; S3: Pouring the retaining wall concrete and curing it; S4: Performing initial calibration of the pressure sensing unit before the filling operation; S5: During and after the filling process, collecting pressure data in real time through the data acquisition and transmission module and transmitting it to the data processing and stability assessment module; S6: The data processing and stability assessment module calculates the real-time safety factor of the retaining wall based on the received pressure data and the pre-stored retaining wall structure parameters; S7: When the safety factor is lower than a preset threshold, the system issues an early warning message.

[0016] Preferably, the calculation of the real-time safety factor of the retaining wall in step S6 specifically includes: based on the reconstructed pressure distribution of the retaining wall, combined with the concrete grade, reinforcement parameters and structural dimensions of the retaining wall, using the thick plate bending theory to calculate the bending moment and axial force currently experienced by the retaining wall, and comparing them with the pre-stored ultimate bending moment and ultimate axial force to obtain the real-time safety factor.

[0017] Compared with the prior art, the present invention has the following advantages and technical effects: 1. The pressure online monitoring system and method for underground mining reinforced concrete filling retaining walls provided by the present invention realizes the integrated design of pressure sensing unit and reinforced concrete retaining wall structure through the pre-embedded components consisting of pre-embedded fixing plate, pre-embedded installation base and pre-embedded cable conduit. The sensor is firmly fixed, which fundamentally solves the problem that traditional sensors are easily washed away and fall off.

[0018] 2. By setting a protective shell with seepage holes and a pressure equalization and transmission layer, the present invention not only effectively protects the sensor from impact, but also solidifies the protective shell and the filling body into a whole, ensuring the authenticity and stability of pressure transmission.

[0019] 3. This invention provides an independent protective channel for signal cables by pre-burying cable conduits, thus preventing damage to the cables during construction and service.

[0020] 4. The data processing and stability assessment module of this invention does not simply display pressure values, but combines the structural parameters and stress model of the retaining wall to calculate the "safety factor" in real time, which can intuitively reflect the safety status of the retaining wall. It directly links the monitoring data with the structural safety assessment, realizes closed-loop management from data collection to risk assessment, and provides reliable technical support for the safe and efficient operation of mine backfilling. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention.

[0022] Figure 1 is a schematic diagram of the pressure online monitoring system for the underground mine reinforced concrete filling retaining wall of the present invention.

[0023] Figure 2 is a schematic diagram of the structure of the pre-embedded component of the present invention.

[0024] Figure 3 is a schematic diagram of the connection between the fixing plate, the mounting base, and the pressure sensing unit of the present invention.

[0025] Figure 4 is a planar schematic diagram of the fixing plate structure of the present invention.

[0026] Figure 5 is a schematic plan view of the mounting base structure of the present invention.

[0027] Figure 6 is a planar schematic diagram of the pressure sensing unit structure of the present invention.

[0028] Figure 7 is a cross-sectional schematic diagram of the pressure sensing unit structure of the present invention.

[0029] In the diagram: 1. Pressure sensing unit; 11. Protective shell; 111. Grout seepage hole; 112. Protective shell fixing wing; 113. Protective shell fixing wing bolt hole; 114. Rubber sealing sleeve; 12. Pressure equalization and transmission layer; 121. Stainless steel sheet; 122. Rubber pad; 13. Pressure sensor body; 2. Embedded fixing plate; 21. Pressure sensing unit installation area; 22. Fixing reinforcement; 23. Bolt hole; 3. Embedded mounting base; 31. Fixing wing; 32. Fixing bolt; 33. Fixing wing bolt hole; 4. Embedded cable conduit; 5. Data acquisition and transmission module; 6. Data processing and stability assessment module. Detailed Implementation

[0030] It should be noted that, unless otherwise specified, the embodiments and features described in this invention can be combined with each other. The described embodiments are merely some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this invention. The invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0031] As shown in Figures 1 to 7, the present invention provides an online pressure monitoring system for reinforced concrete retaining walls in underground mining areas. Its core is to firmly integrate the pressure sensing unit 1 with the reinforced concrete retaining wall body through a carefully designed pre-embedded structure, and to provide a data acquisition, transmission and intelligent stability assessment module to achieve long-term, stable, online monitoring and safety assessment of the stress state of the retaining wall.

[0032] Specifically, the system comprises four core components: pre-embedded components, at least one pressure sensing unit 1, a data acquisition and transmission module 5, and a data processing and stability assessment module 6.

[0033] The pre-embedded components are the cornerstone of this invention's integration of sensors and structure. They include a pre-embedded fixing plate 2, a pre-embedded mounting base 3, and a pre-embedded cable conduit 4. Before the retaining wall is poured, these components need to be integrally fixed to the retaining wall's reinforcing mesh. This design allows subsequent monitoring elements to be precisely and securely pre-positioned in designated locations, providing structural protection and installation reference. By fixing the pre-embedded components to the retaining wall's reinforcing mesh, the reference point of the monitoring system can be integrated with the main structure of the retaining wall, providing a stable physical foundation for the subsequently installed pressure sensing unit and ensuring that it will not shift or detach during concrete pouring and subsequent service.

[0034] The pressure sensing unit 1 is the sensing front end of this invention, and its core function is to sense the pressure exerted on the retaining wall. Each pressure sensing unit 1 is detachably fixed in a corresponding pre-embedded mounting base 3. This detachable design allows for convenient installation and replacement of the sensors after the retaining wall is poured, avoiding damage to the sensors during the pouring process, and also greatly facilitating subsequent inspection and maintenance. When the pressure sensing unit 1 senses pressure, it converts it into a measurable pressure signal.

[0035] The data acquisition and transmission module 5 is located in a relatively safe position underground and is connected to each pressure sensing unit 1 via a pre-embedded cable conduit 4. This module is responsible for periodically or continuously acquiring the pressure signals emitted by all pressure sensing units 1, performing preliminary processing, and then transmitting the signals to the surface via wired or wireless means. The conduit embedded in the concrete provides impenetrable physical protection for the fragile signal cables, effectively isolating them from interference and damage caused by harsh underground environments such as moisture, corrosion, and mechanical stress, ensuring long-term stable data transmission.

[0036] The data processing and stability assessment module 6 is typically located in the surface control room and communicates with the data acquisition and transmission module 5. It is the brain of the entire system, responsible for receiving pressure signals uploaded from downhole and running the core algorithms. Its key function is to calculate, based on this real-time pressure data and combined with pre-stored retaining wall structural parameters (such as dimensions, concrete grade, reinforcement ratio, etc.) and bearing capacity models, a real-time safety factor that intuitively reflects the current safety reserve status of the retaining wall. This transforms isolated pressure values ​​into safety indicators with clear engineering significance, providing the most direct basis for on-site decision-making and avoiding the one-sidedness of relying solely on pressure values ​​for judgment.

[0037] Further optimizing the design, the pre-embedded fixing plate 2 is designed as a rectangular steel plate with a central hollow core. Several fixing reinforcing bars 22 are welded to both ends of the plate, which are inserted into pre-drilled holes in the surrounding rock of the tunnel during construction. Simultaneously, multiple bolt holes 23 are symmetrically arranged on the surface of the pre-embedded fixing plate 2.

[0038] The central hollow area is the pressure sensing unit installation area 21. By setting fixed steel bars 22, the retaining wall, which was originally only connected to the steel mesh, can be further integrated with the surrounding rock of the roadway through the action of anchor bolts, greatly enhancing the anti-slip and anti-overturning capacity of the retaining wall base. At the same time, it also provides an extremely stable support platform for the pre-embedded installation base 3. The bolt holes 23 on the surface of the pre-embedded fixing plate 2 provide positioning and fastening points for the subsequent precise installation of the pre-embedded installation base 3, ensuring that each base can be accurately installed in the design position and that its posture is upright, thus creating conditions for the accurate measurement of the pressure sensing unit 1.

[0039] Further optimizing the design, the pre-embedded mounting base 3 is designed as a steel shell structure with one open side, resembling an open box. Fixing wings 31 extend outwards from the perimeter of its opening, and the fixing wings 31 have fixing wing bolt holes 33 that match the bolt holes 23 of the pre-embedded fixing plate 2. Inside the shell, at the bottom, there are fixing bolts 32 specifically for fixing the pressure sensing unit 1.

[0040] By connecting the fixed wing 31 to the pre-embedded fixing plate 2, a rigid bolted connection can be achieved between the base and the pre-embedded fixing plate 2. This connection method is reliable, easy to install, and removable, ensuring the accuracy and long-term stability of the base's position. By providing fixing bolts 32 for fixing the pressure sensing unit 1, a rigid, repeatedly removable fixing point can be provided for the pressure sensor body 13. This makes the connection between the sensor and the base no longer a simple fit, but a tight connection, achieving rigid coupling between the sensor and the concrete structure, ensuring the continuity and authenticity of the pressure transmission path.

[0041] To further optimize the design, the pressure sensing unit 1 itself is composed of a multi-layered structure to ensure its functionality and durability. It includes the core pressure sensor body 13, a pressure equalization and transmission layer 12 disposed outside its pressure-sensing surface, and an outermost protective shell 11. The protective shell 11 covers the pressure equalization and transmission layer 12 and is fixedly connected to the pre-embedded mounting base 3 by bolts or other means. Multiple grout seepage holes 111 are provided on the protective shell 11.

[0042] By setting up the pressure equalization transmission layer 12, the properties of the material in this layer can be used to disperse and homogenize the point-like and uneven pressure that may exist in the filling body, making the pressure acting on the pressure sensing surface of the pressure sensor body 13 more uniform, thereby effectively reducing measurement errors and improving the representativeness of the data. By opening grout seepage holes 111 on the protective shell 11, a dual function can be achieved: on the one hand, the high-strength protective shell 11 can effectively resist the huge impact at the initial stage of filling grout pouring, protecting the internal precision sensor; on the other hand, the grout seepage holes 111 allow some fine grout to enter and solidify inside the protective shell 11, so that the protective shell 11 eventually forms a whole with the filling body, avoiding the void layer that may be generated due to the smooth surface of the protective shell 11, and ensuring the continuity of pressure transmission. The protective shell 11 is provided with protective shell fixing wings 112 on both sides, and protective shell fixing wings 112 are provided with protective shell fixing wing bolt holes 113. By fixing the protective shell 11 to the pre-embedded mounting base 3, the entire pressure sensing unit 1 can be firmly locked on the pre-embedded mounting base 3, forming a complete and rigid force transmission path from the surrounding rock (through the fixed steel bar 22) to the retaining wall (through the pre-embedded fixing plate 2), and then to the monitoring unit (through the pre-embedded mounting base 3 and the protective shell 11), which restores the true stress state of the retaining wall to the greatest extent.

[0043] In a further optimized design, the pressure equalization and transmission layer 12 includes a rubber pad 122 and a stainless steel sheet 121 stacked sequentially, with the rubber pad 122 positioned close to the pressure sensor body 13.

[0044] By combining the layered rubber pads 122 and stainless steel sheets 121, the advantages of both materials can be utilized. The stainless steel sheets 121 have high hardness and can evenly distribute the pressure from the protective shell 11; while the rubber pads 122 are soft and can further absorb pressure fluctuations and minor unevenness, and provide a buffering and protection effect on the pressure-sensing surface of the pressure sensor body 13, preventing it from being damaged due to excessive local stress.

[0045] To further optimize the design and enhance the survivability of the sensor, a rubber sealing sleeve 114 for sealing the cable interface is also provided on the side of the protective shell 11 facing away from the filling body.

[0046] By setting the rubber sealing sleeve 114, an effective waterproof and dustproof sealing structure can be formed at the cable lead-out point of the pressure sensor body 13. This prevents humid air and moisture from entering the sensor or the pre-embedded mounting base 3 along the cable, preventing short circuits and corrosion. This is an important design detail to ensure the long-term stable operation of the sensor.

[0047] To further optimize the solution, the pre-embedded cable conduit 4 is made of metal or high-strength plastic and is pre-embedded inside the retaining wall to provide an independent protective channel for the cable connecting the pressure sensing unit 1 and the data acquisition and transmission module 5.

[0048] By pre-embedding cable conduit 4 to provide an independent protective channel for the cables, all signal lines can be centrally protected, completely isolating them from direct contact and corrosion by concrete. This also prevents cables from being broken due to subsequent settlement or deformation caused by haphazard cable arrangement inside the retaining wall. This independent channel greatly improves the reliability of signal transmission and the service life of the entire system.

[0049] Further optimizing the scheme, the surface data processing and stability assessment module 6 integrates multiple functional units to achieve complex analysis functions. It includes: a data processing unit, used for preprocessing the received raw pressure signal such as denoising, filtering, and temperature compensation, and reconstructing the pressure distribution cloud map or curve on the retaining wall surface by combining data from multiple measuring points; and a bearing capacity calculation unit, whose internal database pre-stores the design parameters of the retaining wall, such as concrete grade, reinforcement information, thickness, and span, and can calculate the ultimate bearing capacity of the retaining wall under different stress modes, such as the ultimate bending moment M. 31p and ultimate axial force N 31pThe safety factor calculation unit is responsible for comparing the current load (such as bending moment M(t) and axial force N(t)) transmitted from the data processing unit with the ultimate bearing capacity pre-stored in the bearing capacity calculation unit, and calculating the safety factor in real time. The early warning unit is responsible for monitoring the value of the safety factor; once it is found to be lower than the preset safety threshold, or abnormal pressure growth rate or increased bias distribution is detected, a graded alarm is immediately triggered. The real-time safety factor is calculated based on the retaining wall parameters, and its calculation formula is as follows: The data processing and stability assessment module 6 constructs a complete data processing and decision support chain through a data processing unit, a carrying capacity calculation unit, a safety factor calculation unit, and an early warning unit. It not only displays data but also deeply mines and integrates it, ultimately outputting safety factors and early warning signals that provide directly guiding decision-making information, truly realizing an intelligent closed loop for the monitoring system from perception to assessment to early warning.

[0050] This invention also discloses a method for online pressure monitoring based on the above system, the specific implementation steps of which are as follows: S1: Construction of embedded parts. During the retaining wall formwork and steel mesh binding stage, according to the design drawings, the embedded fixing plate 2 is anchored into the surrounding rock through its fixing steel bars 22, and its plate body is welded or bound firmly to the steel mesh. Subsequently, the embedded mounting base 3 is fixed to the hollow area of ​​the embedded fixing plate 2 through the fixing wings 31 and bolts. At the same time, the embedded cable conduit 4 is laid according to the design path, and its two ends are respectively led to the position of the embedded mounting base 3 and the position of the future data acquisition and transmission module 5.

[0051] S2: Install the sensing unit. After the retaining wall formwork, reinforcing bars, and all embedded parts have passed inspection, before or after pouring concrete (depending on the specific process design), install the pressure sensor body 13 inside the embedded mounting base 3 using fixing bolts 32. Then, place the rubber pad 122 and the stainless steel sheet 121 in sequence, and finally install the protective shell 11 with grout seepage holes 111 and fix it to the embedded mounting base 3. Pass the cable of the pressure sensor body 13 through the rubber sealing sleeve 114 of the protective shell 11 and introduce it into the embedded cable conduit 4.

[0052] S3: Concrete Pouring and Curing. After all installation and inspection are completed, the retaining wall concrete shall be poured. During the pouring process, direct contact between the vibrator and embedded components and cable conduits should be avoided. The concrete shall be cured to standard conditions until it reaches its design strength.

[0053] S4: System Calibration. Before starting the filling operation in the mining area, start the system, read the initial value and zero point calibration for each pressure sensor unit 1, and record the initial reading as the reference value.

[0054] S5: Real-time data acquisition. After filling begins, the downhole data acquisition and transmission module 5 automatically acquires data from all pressure sensing units 1 at a preset frequency (e.g., 1-30 seconds / time) and uploads it in real time to the surface data processing and stability assessment module 6 via fiber optic or other communication methods.

[0055] S6: Safety Factor Calculation. After receiving the data, the data processing and stability assessment module 6 first performs preprocessing and pressure distribution reconstruction. Then, it calls the bearing capacity model of the retaining wall to convert the current pressure distribution into equivalent structural internal forces (bending moment M(t), axial force N(t)). Finally, it calculates the real-time safety factor.

[0056] S7: Early Warning and Post-Evaluation. The system displays the real-time safety factor value. When the real-time safety factor falls below the set early warning threshold or other abnormal criteria occur, the early warning unit immediately issues an audible and visual alarm. All data from the entire filling process and subsequent monitoring are automatically archived for post-process analysis and filling process optimization.

[0057] Through steps S1 to S7, the entire monitoring process can be precisely controlled, ensuring that the system is under control from construction to operation, thus maximizing the effectiveness of monitoring data and the reliability of system early warning.

[0058] The pressure online monitoring system and method for reinforced concrete retaining walls in underground mining areas provided by this invention intervenes in the entire implementation process from the initial construction of the retaining wall, pre-embedding the monitoring elements as part of the structure, fundamentally solving the problem of low sensor survival rate. Throughout the entire life cycle of the filling operation, the system continuously senses the stress changes of the retaining wall and, through an original algorithm, transforms these raw physical quantities into a safety factor directly linked to the engineering design. Ultimately, mine managers can monitor the safety status of each retaining wall hundreds of meters underground in real time from the control room using an intuitive safety factor. When the safety factor approaches the critical value, the system can issue an early warning, gaining valuable time to take reinforcement measures or adjust the filling plan. This technology not only greatly improves the safety of mine filling operations and effectively avoids slurry overflow accidents, but also accumulates a large amount of valuable real stress data on the retaining walls, providing a scientific basis for future optimization of retaining wall design parameters and reduction of construction costs, and is a key link in the intelligent and safe development of mines.

[0059] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. An online pressure monitoring system for reinforced concrete retaining walls in underground mining areas, characterized in that, include: The pre-embedded components include a pre-embedded fixing plate (2), a pre-embedded mounting base (3), and a pre-embedded cable conduit (4), which are used to fix and connect with the steel mesh of the retaining wall before the retaining wall is poured; at least one pressure sensing unit (1), which is detachably installed in the pre-embedded mounting base (3), is used to sense the pressure on the retaining wall and generate a pressure signal; a data acquisition and transmission module (5), which is set in the well and connected to the pressure sensing unit (1) through the pre-embedded cable conduit (4), is used to acquire and transmit the pressure signal; and a data processing and stability judgment module (6), which is communicatively connected to the data acquisition and transmission module (5), is used to receive the pressure signal and calculate the real-time safety factor based on the bearing capacity model of the retaining wall.

2. The pressure online monitoring system for reinforced concrete retaining walls in underground mining areas according to claim 1, characterized in that, The pre-embedded fixing plate (2) is a plate-shaped structure with a central hollow. The two ends of the pre-embedded fixing plate (2) are provided with fixing steel bars (22) for anchoring into the surrounding rock. The plate surface of the pre-embedded fixing plate (2) is provided with bolt holes (23) for connecting the pre-embedded mounting base (3).

3. The pressure online monitoring system for reinforced concrete retaining walls in underground mining areas according to claim 1, characterized in that, The pre-embedded mounting base (3) is a shell structure with one side open. The periphery of the opening is provided with fixing wings (31) for connecting with the pre-embedded fixing plate (2). The interior of the shell structure is provided with fixing bolts (32) for fixing the pressure sensing unit (1).

4. The pressure online monitoring system for reinforced concrete retaining walls in underground mining areas according to claim 1, characterized in that, The pressure sensing unit (1) includes: a pressure sensor body (13); a pressure equalization transmission layer (12) disposed on the outside of the pressure sensing surface of the pressure sensor body (13) for uniformly transmitting external pressure; and a protective shell (11) covering the outside of the pressure equalization transmission layer (12) and fixedly connected to the pre-embedded mounting base (3), wherein the protective shell (11) is provided with a plurality of grouting holes (111).

5. The pressure online monitoring system for reinforced concrete retaining walls in underground mining areas according to claim 4, characterized in that, The pressure equalization transmission layer (12) includes a rubber pad (122) and a stainless steel sheet (121) stacked in sequence, with the rubber pad (122) positioned close to the pressure sensor body (13).

6. The pressure online monitoring system for reinforced concrete retaining walls in underground mining areas according to claim 4, characterized in that, The protective shell (11) is also provided with a rubber sealing sleeve (114) for sealing the cable interface on the side opposite to the filling body.

7. The pressure online monitoring system for reinforced concrete retaining walls in underground mining areas according to claim 1, characterized in that, The pre-embedded cable conduit (4) is made of metal or high-strength plastic and is pre-embedded inside the retaining wall to provide an independent protective channel for the cable connecting the pressure sensing unit (1) and the data acquisition and transmission module (5).

8. The pressure online monitoring system for reinforced concrete retaining walls in underground mining areas according to claim 1, characterized in that, The data processing and stability assessment module (6) includes: a data processing unit for filtering and correcting the received pressure signal and reconstructing the pressure distribution on the surface of the retaining wall; a bearing capacity calculation unit for storing and calling the ultimate bearing capacity parameters of the retaining wall; a safety factor calculation unit for calculating the safety factor of the retaining wall in real time based on the pressure distribution and the ultimate bearing capacity parameters; and an early warning unit for issuing an alarm signal when the safety factor is lower than a preset threshold.

9. A method for online pressure monitoring of a reinforced concrete retaining wall in an underground mining area based on the system described in any one of claims 1 to 8, characterized in that, Includes the following steps: S1: Before pouring the retaining wall, fix the pre-embedded assembly consisting of the pre-embedded fixing plate (2), the pre-embedded mounting base (3), and the pre-embedded cable conduit (4) to the retaining wall steel mesh; S2: Install and fix the pressure sensing unit (1) in the pre-embedded mounting base (3), and lead the cable out through the pre-embedded cable conduit (4); S3: Pour the retaining wall concrete and cure it; S4: Before the filling operation, perform initial calibration on the pressure sensing unit (1); S5: During and after filling, pressure data is collected in real time through the data acquisition and transmission module (5) and transmitted to the data processing and stability judgment module (6). S6: Data processing and stability assessment module (6) calculates the real-time safety factor of the retaining wall based on the received pressure data and the pre-stored retaining wall structure parameters; S7: When the safety factor is lower than the preset threshold, the system issues a warning message.

10. The method for online pressure monitoring of reinforced concrete retaining walls in underground mining areas according to claim 9, characterized in that, The calculation of the real-time safety factor of the retaining wall in step S6 specifically includes: based on the reconstructed pressure distribution of the retaining wall, combined with the concrete grade, reinforcement parameters and structural dimensions of the retaining wall, using the thick plate bending theory to calculate the bending moment and axial force currently experienced by the retaining wall, and comparing them with the pre-stored ultimate bending moment and ultimate axial force to obtain the real-time safety factor.

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