Construction method and system for preventing the slide of the shaft lining of an inclined shaft open section

Abstract

This invention discloses a construction method and system for preventing slippage in the open trench section of an inclined shaft, aiming to solve the problem of slippage instability during the construction of the open trench section and the excavation of the tunnel. The method includes: constructing a pre-compressed, trumpet-shaped composite wall seat at the bottom of the open trench, precisely controlling the prestress through a deformation coordination equation to actively compress the wall seat against the rock mass; before tunnel excavation, constructing a circumferentially pre-reinforced anchor cable arch at the tunnel entrance to achieve a smooth load transition; and collecting stress and displacement data in real time through an intelligent monitoring system, assessing the stability state based on a slippage driving force prediction model, and performing dynamic stress compensation on the anchoring system. This invention, through a dual-synergistic anti-slip system of bottom pre-compression and tunnel entrance pre-reinforcement, achieves a shift from passive resistance to active pre-control, ensuring the safety and stability of the entire construction cycle of the open trench section of the inclined shaft.

Description

Technical Field

[0001] This invention relates to the field of underground engineering construction technology, specifically to a construction method and system for preventing slippage of the well wall in the open trench section of an inclined shaft. Background Technology

[0002] When constructing inclined shaft projects in mountainous areas or under complex geological conditions, the open trench section connecting the surface and underground structures typically employs the open-cut, cast-in-place reinforced concrete lining method. Because this section is situated within an inclined trench, during concrete pouring and curing, the downward component of the structure's self-weight along the inclined surface can easily exceed the initial frictional force between its bottom surface and the initially set concrete or bedrock, leading to cumulative downward slippage of the shaft wall. Even more seriously, when construction transitions from the open trench to the tunnel, the front end of the shaft wall becomes a free surface, completely losing the original passive earth pressure at the front end. This causes a sudden increase in the downward force, often resulting in major engineering accidents such as overall displacement of the constructed shaft wall, structural cracking, or even collapse.

[0003] Traditional anti-slip measures mainly rely on increasing the foundation area, setting simple anti-slip keys, or relying on the structure's own weight for friction. These are all passive resistance modes, and their reliability heavily depends on the inherent strength of the foundation soil and rock. They cannot proactively establish and quantify anti-slip capabilities before construction. Especially in conditions of fractured, severely weathered, or steeply inclined rock masses, traditional methods often fail. Therefore, there is an urgent need for an anti-slip system that can be proactively established, precisely controlled, and works in synergy with the rock mass in the early stages of construction to ensure the stability of the shaft wall during the construction of the open-cut section of the inclined shaft. Summary of the Invention

[0004] To address the aforementioned shortcomings in the prior art, this invention provides a construction method and system for preventing slippage of the well wall in the open trench section of an inclined shaft.

[0005] To achieve the above-mentioned objectives, the technical solution adopted by this invention is as follows: A construction method for preventing slippage of the well wall in the open trench section of an inclined shaft includes the following steps: S1. Excavate and construct a funnel-shaped reinforced concrete wall base embedded in stable rock mass at the bottom of the open trench. The wall base is pre-stressed with a prestressed anchor cable anchored to the deep rock mass, and prestress is applied to the anchor cable to pre-compress the wall base and the rock mass. S2. On the wall base, the main body of the well wall is poured in sections from bottom to top; S3. Before excavating the entrance of the dark cave, a circumferential pre-reinforced anchor cable arch is constructed in the rock mass outside the end of the well wall, and prestress is applied to the arch. S4. Based on real-time monitoring data, dynamic stress compensation is performed on at least one of the prestressed anchor cables and the advanced pre-reinforced anchor cable arch frame to maintain the synergistic anti-slip capability of bottom pre-stressing and opening pre-reinforcement.

[0006] Furthermore, the initial tension control stress of the prestressed anchor cable in S1 is determined by calculation using a deformation compatibility equation based on the elastic modulus of the rock mass and concrete, interface characteristics, and design prestress value. The deformation compatibility equation is as follows:

[0007] In the formula, The elastic modulus of concrete. The comprehensive elastic modulus of the rock mass. and These represent the effective transfer lengths of prestress in concrete and rock mass, respectively. To design the effective compressive stress that is expected to be transferred to the critical face of the rock mass, To account for the equivalent deformation due to interface roughness and shear dilatation.

[0008] Furthermore, in step S3, the advanced pre-reinforced anchor cable arch is composed of multiple prestressed anchor cables arranged in an umbrella-like radial pattern, with its tensioning end connected to the end structure of the well wall, thereby achieving three-dimensional pre-reinforcement of the rock mass in front of and to the side of the tunnel entrance.

[0009] Furthermore, S4 specifically includes: S41. Real-time monitoring of wellbore stress, displacement, and prestress value of anchoring system through sensor network; S42. Based on monitoring data, the sliding driving force prediction model is used to assess the structural stability. S43. When the evaluation results meet the preset quantification threshold, the compensation tension of the specified anchoring element is initiated to realize the closed-loop dynamic control of the anti-slip system.

[0010] Furthermore, the sensor network in S41 includes an earth pressure cell deployed on the bottom surface of the wall base, a fiber optic stress sensor on the anchor cable, and a three-dimensional laser displacement scanning prism on the surface of the well wall.

[0011] Furthermore, the glide driving force prediction model in S42 calculates the total glide driving force using the following formula:

[0012] in, As the driving force of the overall decline, For the first The wall of the well has its own weight. The inclination angle of the inclined shaft. For construction dynamic load coefficient, For example, is the environmental force, and Fu is the unloading force during the excavation of the tunnel.

[0013] A smart anti-slip system for the wellbore wall of an open-cut section of an inclined shaft includes: The pre-compressed funnel-shaped wall base and the pre-reinforced arch frame at the entrance of the dark hole form an active anti-slip skeleton that works in coordination between the bottom and the entrance. The intelligent control system, which is connected to the active anti-slip skeleton, is used to dynamically compensate and control the prestress of the anchoring system based on monitoring data, so as to maintain the long-term stability of the anti-slip skeleton.

[0014] Furthermore, the active anti-slip skeleton includes: The first group of prestressed anchor cables is embedded in the funnel-shaped wall base and is spatially radially distributed; A second group of prestressed anchor cables is arranged around the entrance of the dark cave and connected to the end of the well wall at the tensioning end.

[0015] Furthermore, the intelligent control system includes: The collaborative anti-slip structural module consists of a spatial collaborative force-bearing skeleton composed of a pre-compressed composite wall seat embedded in the bedrock and an advanced pre-reinforced arch frame at the entrance of the dark cave. The global perception and monitoring network consists of a distributed array of fiber optic stress sensors, a three-dimensional laser displacement scanner, and a data acquisition module, used to acquire information on the mechanical state and spatial location of the structure in real time. The intelligent analysis and decision-making module includes a data processing unit, a downward trend prediction algorithm module, a stress compensation decision model and an early warning module. It is used to receive monitoring data, evaluate the structural stability through the algorithm model, and generate stress compensation instructions when needed. The dynamic execution and compensation device includes a re-tensionable prestressed anchor cable, a servo-controlled hydraulic tensioning device and a corresponding control system, which is used to execute the compensation tensioning command issued by the intelligent central hub to achieve closed-loop dynamic control of anti-slip capability.

[0016] The present invention has the following beneficial effects: This method systematically solves the major technical challenges in the background technology of shaft wall slippage due to self-weight and construction loads in the open trench section of inclined shafts, and sudden instability due to the open space at the front end during tunnel excavation. It transforms traditional passive and static anti-slip measures into active and dynamic full-process control by constructing a collaborative anti-slip system composed of pre-compressed composite wall seats and pre-reinforced arch frames at the tunnel entrance. Specifically, prestressed active loading is applied at the beginning of construction to establish strong normal pressure and frictional resistance at key interfaces, fundamentally suppressing the slippage trend. Especially for the high-risk node of tunnel excavation, the innovative use of pre-reinforced arch frames achieves a smooth load transition, eliminating the risk of instability. Finally, combined with full-cycle intelligent monitoring and dynamic compensation, quantifiable design, real-time monitoring, and adaptive maintenance of anti-slip capacity are achieved, ensuring the inherent safety of the project under all working conditions and demonstrating extremely high reliability and significant technical and economic efficiency. Attached Figure Description

[0017] Figure 1 This is a flowchart illustrating a construction method for preventing slippage of the well wall in an open trench section of an inclined shaft.

[0018] Figure 2 This schematic diagram illustrates the composition of an electronic device according to an exemplary embodiment of the present disclosure.

[0019] Figure 3 The schematic diagram illustrates the composition of a storage medium in an exemplary embodiment of the present disclosure. Detailed Implementation

[0020] The specific embodiments of the present invention are described below to enable those skilled in the art to understand the present invention. However, it should be understood that the present invention is not limited to the scope of the specific embodiments. For those skilled in the art, various changes are obvious as long as they are within the spirit and scope of the present invention as defined and determined by the appended claims. All inventions utilizing the concept of the present invention are protected.

[0021] Example 1

[0022] See Figure 1 This application addresses the shortcomings of existing technologies by providing a method and intelligent control system for active anchoring construction of inclined shaft open-cut sections based on multiple anti-slip synergy. This method abandons the passive anti-slip concept and constructs a multi-synergistic anti-slip system comprising pre-compacted composite wall seats, distributed lateral anchoring, and real-time dynamic compensation. Furthermore, it introduces an intelligent control mechanism to pre-suppress the downward trend of the well wall, monitor the process, and adaptively adjust it, fundamentally ensuring construction safety and structural accuracy.

[0023] The technical solution of the present invention: Firstly, a construction method and system for preventing slippage of the well wall in the open trench section of an inclined shaft is provided. The method includes the following steps performed in sequence: Step 1: Geological modeling and dynamic calculation of anti-sliding requirements.

[0024] After the open trench excavation is completed, a detailed geological survey and parameter identification are conducted on the exposed bottom and sidewall rock masses of the trench. A three-dimensional geomechanical model of the open trench section is established using the survey data. Based on this model, the sliding driving force of the well wall structure at different construction stages is calculated in real time. The construction stages include at least: the stage of segmental well wall pouring, the concrete hardening stage, and the initial stage of excavation of the tunnel entrance; the sliding driving force is the vector sum of the structural self-weight sliding component, the additional force of construction dynamic load, and the environmental forces at each stage.

[0025] Step 2: Construction of the trumpet-shaped composite wall base and active prestressing loading.

[0026] At the designed location at the bottom of the open trench, an inverted funnel-shaped foundation pit is excavated downwards, embedding itself within the stable rock mass. A three-dimensional spatial prestressed anchoring network is erected within the pit. This network consists of multiple bundles of high-strength prestressed anchor cables distributed radially in space, with the distal ends of the cables anchored to the stable rock mass below and laterally. Subsequently, micro-expansion high-strength concrete is poured to form a reinforced concrete funnel-shaped composite wall seat tightly bonded to the rock mass. After the concrete reaches its design strength, all prestressed anchor cables are simultaneously tensioned in stages. The tensioning control stress is determined based on the maximum downward driving force calculated in step one and the theory of coordinated deformation at the rock-concrete interface. This ensures that the bottom and lateral interfaces of the wall seat are pre-compressed before bearing the well wall load, generating significant normal constraint force and static friction.

[0027] Step 3: Segmented casting of the main body of the well wall.

[0028] Above the wall base, the main body of the well wall is poured in sections from bottom to top. There is no need to install anchor bolts on the side. The anti-slip effect is achieved by the pre-loading of the wall base and the subsequent pre-reinforcement of the opening.

[0029] Step 4: Pre-reinforcement of the entrance to the dark cave and smooth transition of load.

[0030] Before excavating the tunnel entrance, a ring-shaped pre-reinforced arch is constructed outside the outline of the tunnel's initial section, adjacent to the end of the open trench section's wall. This arch is constructed from multiple large-diameter prestressed anchor cables deeply embedded in stable rock mass. The anchor cables are distributed in an umbrella shape around the tunnel entrance, with their tensioned ends reliably connected to the end wall of the open trench section. By tensioning this ring-shaped anchor cable group, a strong load transfer bridge is pre-established between the end of the tunnel wall and the rock mass in front before excavation of the tunnel entrance. This ensures that during tunnel excavation and unloading, the supporting force originally borne by the front rock mass can be smoothly and gradually transferred to the pre-reinforced arch and the stable rock mass behind, preventing the tunnel wall from becoming unstable due to sudden unloading at the front.

[0031] Step 5: Full-cycle intelligent monitoring and dynamic stress compensation.

[0032] During the construction of the open-cut section and the excavation of the tunnel entrance, an intelligent monitoring and feedback system was constructed. This system includes three-dimensional laser displacement scanning monitoring points deployed on the well wall surface. The system collects structural stress and displacement data in real time and transmits it to a central processing unit. The processor incorporates a downward trend prediction algorithm and a stress compensation decision model.

[0033] Specifically, the system presets three levels of early warning and compensation thresholds: When the measured sliding driving force reaches 70% of the current stage design resistance, or the stress loss of the key anchor cable exceeds 10% of the initial value, or the daily displacement increase of the well wall exceeds 2mm, the system issues a yellow warning, indicating the risk and recommending that the monitoring frequency be increased.

[0034] When any of the above indicators reaches the red threshold (sliding force ≥ 85% of design resistance, or anchor cable stress loss ≥ 15%, or daily displacement ≥ 3mm), the system will automatically or manually initiate the compensation tensioning program.

[0035] By using a servo tensioning device, the specified prestressed anchor cables or anchor rods are subjected to secondary tensioning to restore their anchoring force to 95%~100% of the initial design value, and then re-enter the monitoring cycle after compensation. This achieves dynamic maintenance and adaptive enhancement of anti-slip capacity.

[0036] In this embodiment, the mathematical model and calculation formulas in the present invention are not abstract theories, but core tools that directly guide engineering design and construction decisions. The aim is to transform traditional experience-based, qualitative construction into precise control based on quantitative analysis and scientific prediction. The following provides a detailed explanation of the engineering meaning, application scenarios, and specific roles of the core formulas in this invention.

[0037] The calculation model for the downward driving force described in step one is expressed mathematically as follows: Assume the design inclination angle of the inclined shaft open channel is . , No. The self-weight of the well wall is The equivalent coefficient of dynamic load during construction is Environmental forces are Then the total downward driving force in this stage This can be expressed as:

[0038] The total design resistance of the anti-slip system Must meet: ,in This represents the predicted maximum downward driving force during the entire construction period. For the overall safety factor, the value should be no less than 2.5.

[0039] The component of the sliding force due to its own weight: This is a component of the sliding force; the sliding force and the total weight of the wellbore are clearly defined. and tilt angle It is proportional to the sine function; in actual construction segmented pouring, this formula can be used to calculate the cumulative sliding force of the currently poured segment in real time, rather than just calculating the final value; for example, when pouring to the 3rd segment, n=3, so as to dynamically evaluate the anti-slip force required for the construction node.

[0040] Construction dynamic load factor: This factor quantifies the amplification effect of construction activities, such as concrete impact and equipment vibration, on static sliding force; different factors are assigned to different processes based on field testing and experience. This value makes the calculation more closely reflect actual working conditions.

[0041] For environmental forces, Excavation unloading force: These two force terms are the inventive considerations of this invention.

[0042] The potential increase in sliding force due to environmental factors such as rock mass softening caused by rainfall infiltration and changes in groundwater pressure was proactively considered. Specifically targeting the high-risk condition of tunnel excavation, numerical simulations or theoretical estimations were used to quantify the support loss effect caused by the removal of the rock mass in front; this is a key force that traditional methods completely ignore.

[0043] Specifically, in the design phase of this application's technical solution: This is used to determine the overall resistance design target of the anti-slip system. Safety factor The selection is also based on the Scientific assessment of various uncertainties in e-computation.

[0044] Specifically: Total resistance of the anti-slip system .

[0045] The resistance of the wall base foundation is mainly provided by the static friction force generated by the preload stress. ,in Let f be the bottom area of ​​the wall base, and f be the comprehensive friction coefficient.

[0046] To strengthen the arch support at the tunnel entrance: Through spatial mechanics analysis, the prestress of the annular anchor cable group is decomposed into the sum of axial components that resist the sliding of the well wall.

[0047] In the embodiments, respectively calculated >10000kN, ≈12672kN. Even with a conservative estimate Contribution It also far exceeds the design requirements (29040kN); this data proves the safety redundancy of the multi-cooperative system.

[0048] During the construction phase, it serves as the core input to the predictive model of the intelligent monitoring system. The system collects construction progress (number of poured sections n) and monitors environmental data (such as pore water pressure) in real time for correction. ), and input the tunnel excavation plan in advance (to determine The system can dynamically predict the downward force at any future point in time (the duration of its action), thus enabling early warning.

[0049] Furthermore, the calculation of the initial tension control stress σinitial for prestressed active loading in step two needs to consider the difference in elastic modulus between the rock mass and concrete, as well as the interface dilatation effect, and is obtained by solving the following deformation compatibility equations:

[0050] in, The elastic modulus of concrete. The comprehensive elastic modulus of the rock mass. and These represent the effective transfer lengths of prestress in concrete and rock mass, respectively. To design the effective compressive stress that is expected to be transferred to the critical face of the rock mass, To account for the equivalent deformation caused by interface roughness and shear dilatation, this equation ensures the effective establishment and transfer of prestress.

[0051] This equation describes the mechanical process of prestress being transferred from the tensioning end to the target interface. The key is to ensure that the prestress can be effectively applied.

[0052] Initial tension control stress: This is a construction parameter that can be directly controlled, for example, by controlling the hydraulic pressure reading of the jack.

[0053] Effective compressive stress at the interface: This is the desired design target and directly determines the magnitude of the anti-slip friction force.

[0054] , and , : Represents the elastic modulus of concrete and rock mass, and the transmission length of prestress within them, respectively; revealing the soft rock mass ( Small or short anchorage length ( Small (increased) prestress will be largely consumed in rock mass deformation, making much smaller .

[0055] This is a correction term for the equivalent deformation of the interface; it quantifies the roughness produced by artificial roughening of the pit wall and the small shear expansion (dilatation) effect that may occur at the interface under preload. The existence of this allows for a proper reduction in theoretical... Because the rough interface itself will produce an additional self-locking effect after being compressed, it avoids the risk of material waste or rock mass damage caused by blind over-tensioning.

[0056] In practical applications, the design objective of prestressed wall base design is to establish an average compressive stress at the bottom of the wall base: .

[0057] Known moderately weathered sandstone =5.0GPa, concrete =33.0 GPa, estimated through field tests. , and Substitute these parameters into the equation to calculate the required... It should be 0.65 times the standard value of the steel strand strength, thus providing a precise, economical, and safe tension control value.

[0058] As can be seen, the formula system in this invention takes into account geological conditions ( , ), material properties ( ), structural design ( , ), construction parameters ( Anchor bolt arrangement) and dynamic loads ( , All of these are incorporated into a quantifiable and adjustable closed loop; it is not merely a theory in papers or design books, but an engineering language and instruction that directly drives intelligent tensioning equipment, guides drilling layout, and triggers early warning signals. It is the core intellectual support for this invention to achieve the leap from experience-based construction to computational construction.

[0059] The equation clarifies the interface treatment (roughening to improve) ) and ensure sufficient anchorage length (increase) This is crucial for ensuring the effectiveness of prestressing. This directly translates into clear construction quality requirements for roughening the pit sidewalls and the length of the anchor cable anchorage section.

[0060] Secondly, an intelligent control system for implementing the above method is provided, characterized in that the system comprises: Synergistic anti-slip structural system: a spatial synergistic force-bearing skeleton composed of a pre-compressed composite wall seat embedded in the bedrock and an advanced pre-reinforced arch frame at the entrance of the dark cave.

[0061] The global perception and monitoring network consists of a distributed array of fiber optic stress sensors, a three-dimensional laser displacement scanner, and a data acquisition module, used to acquire information on the structural mechanical state and spatial location in real time.

[0062] The intelligent analysis and decision-making center comprises a data processing unit, a glide trend prediction algorithm module, a stress compensation decision model, and an early warning module. This center receives monitoring data, assesses the structural stability through the algorithm model, and generates stress compensation commands when necessary. The stress compensation decision model incorporates the aforementioned early warning and action thresholds (glide force, stress loss, displacement rate), as well as compensation target values.

[0063] Dynamic execution and compensation device: It consists of a re-tensionable prestressed anchor cable, a servo-controlled hydraulic tensioning device and a corresponding control system. It is used to execute the compensation tensioning command issued by the intelligent central hub to realize closed-loop dynamic control of anti-slip capability.

[0064] Example 2

[0065] To make the technical solution, innovative features and beneficial effects of the present invention clearer, the following non-limiting description is provided in conjunction with embodiments.

[0066] This invention was implemented in an open-cut section of an inclined shaft with an inclination angle of 25 degrees. First, after the open-cut excavation was completed, ground-penetrating radar and core drilling were used to explore the foundation and establish a three-dimensional geological model. The predicted maximum sliding driving force was calculated to be 8500 kN.

[0067] Subsequently, an inverted trumpet-shaped composite wall seat was constructed at the bottom end of the trench. The excavation pit was deepened to 4 meters to intact bedrock, and 24 bundles of prestressed anchor cables were embedded in a spatially radial distribution, with a design force of 450kN per bundle. C40 micro-expansion concrete was poured, and after the strength reached 90%, all anchor cables were tensioned simultaneously in three stages to the design tonnage. Deformation compatibility equations were used to verify that the effective prestress was established at the rock interface at the bottom of the wall seat.

[0068] The main body of the well wall is poured in sections from bottom to top on the wall base, without the need for lateral anchor bolts, relying on the pre-stressing of the wall base to provide basic anti-slip force.

[0069] Before excavating the underground tunnel, after the well wall of the open trench section is poured to the end, a ring-shaped pre-reinforced arch frame is constructed 2 meters outside the designed tunnel opening outline. Sixteen 12-meter-long heavy-duty prestressed anchor cables are installed in an umbrella shape, diagonally forward and laterally into the rock mass. The ends of the anchor cables are connected to the end structure of the well wall through a special steel arch frame and tensioned as a whole to the design load.

[0070] Throughout the construction process, stress and displacement data were transmitted in real time to the intelligent control center via pre-embedded sensors and surface monitoring points. The control center's built-in algorithm model continuously performed stability assessments. After the initial blast at the tunnel entrance, monitoring showed slight fluctuations in stress at the end of the well wall, with the stress loss of key anchor cables reaching 12% of the initial value, triggering a yellow alert. The system automatically suggested compensating for the tensioning of four key anchor cables in the pre-reinforced arch frame at the tunnel entrance. After confirmation by the operators, the compensating tensioning was performed to 98% of the initial value, and the stress fluctuations quickly returned to stability, ensuring construction safety.

[0071] The above embodiments demonstrate that the method and system of the present invention can effectively construct a multi-layered, proactive, and intelligent anti-slip system, ensuring the stability of the well wall in the open channel section of the inclined shaft throughout the entire process.

[0072] Example 3

[0073] To enable those skilled in the art to more deeply understand the technical solution, innovative points, and implementation details of this invention, a more detailed and non-limiting description of the invention will be provided below with reference to a typical engineering embodiment. This embodiment demonstrates the entire process from design to construction completion.

[0074] Application of open channel section in main inclined shaft of a certain mining area 1. A new main inclined shaft is being built in an iron mine, with a designed inclination angle of α=28°, a length of 42 meters for the open trench section, and an excavation depth of 8-15 meters. The exposed strata, from top to bottom, are: a 4-meter-thick layer of gravelly soil, a 6-10-meter layer of strongly weathered sandstone, and below that, moderately weathered sandstone.

[0075] The design employs cast-in-place C30 reinforced concrete lining with a wall thickness of 600mm. The core challenges are: a large dip angle and significant sliding force; a deep, highly weathered layer and a low base friction coefficient; and when transitioning to the dark tunnel construction, the tunnel entrance is located in an unstable rock layer, posing an extremely high risk of the well wall becoming unstable.

[0076] 2. Detailed Explanation of Implementation Steps Step 1: After the open trench was excavated and shaped, construction did not begin immediately. Instead, a detailed supplementary survey was conducted first. Geological modeling: Ground-penetrating radar survey lines and supplementary exploration boreholes were laid out in a 5m×5m grid on the bottom and sidewalls of the trench to accurately delineate the interface between strongly weathered and moderately weathered rock strata, and a three-dimensional bedrock surface contour map was drawn. The comprehensive elastic modulus of each rock stratum was obtained through field point load tests and laboratory tests. (0.5 GPa for strongly weathered layer and 5.0 GPa for moderately weathered layer), internal friction angle and base comprehensive friction coefficient f (conservatively taken as 0.35 in design).

[0077] Dynamic calculation of load and sliding force: The component of the structure's self-weight sliding force ( The total weight of the 42-meter well wall is approximately 18,500 kN. .

[0078] Construction dynamic load ( Considering concrete pumping, vibration, and equipment loads, the dynamic load factor is taken. =1.2. .

[0079] Unloading force during tunnel excavation ( Numerical simulation software was used to simulate the working condition of removing 5 meters of rock in front of the tunnel entrance in one go, and the additional sliding thrust acting on the end of the well wall was calculated to be about 1200kN.

[0080] Total maximum downward driving force Considering the following combination: the well wall has been fully poured and the entrance to the hidden cave has just been excavated. .

[0081] Resistance design standard: Take the comprehensive safety factor =2.5, then the total design resistance Rtotal of the anti-skid system must reach: =2.5*11616=29040kN.

[0082] Step 2: Construction of the funnel-shaped composite wall base and active prestressing loading Excavation of the foundation pit: Below the starting point of the open trench design, an inverted trumpet-shaped foundation pit is precisely laid out and excavated. The upper diameter is 6 meters, and the pit is excavated downwards at a 60° divergence angle to a depth of 4.5 meters, ensuring that it is situated within a moderately weathered sandstone layer for at least 2.0 meters. The sidewalls of the foundation pit are manually roughened to create an uneven, rough surface.

[0083] Prestressed anchor cable network layout: A three-dimensional prestressed anchor cable network is installed within the foundation pit. A total of 24 bundles of 7Φ15.2mm high-strength, low-relaxation steel strand anchor cables are arranged, with a designed single bundle bearing capacity of 750kN. The anchor cables are arranged in three rings: The center consists of 6 straight anchor rings: driven vertically downwards, with an anchorage section of 6 meters, penetrating into the stable rock layer below the bottom of the foundation pit; the middle layer consists of 9 inclined anchor rings: driven radially into the rock mass on the side of the foundation pit at a 30° angle to the vertical, with an anchorage section of 5 meters; the outer layer consists of 9 inclined anchor rings: driven into the outermost rock mass at a 45° angle to the vertical, with an anchorage section of 5 meters. All free sections of the anchor cables are fitted with corrugated pipes to isolate them from the concrete.

[0084] Wall base casting and tensioning: Double-layer steel mesh is tied and reliably welded to the anchor cable positioning frame, and C40 micro-expansion concrete is poured. After curing for 7 days and reaching 90% strength, intelligent synchronous graded tensioning is performed.

[0085] Based on the rock mass parameters and design requirements from step one, a prestress of 1.5 MPa is established at the rock mass interface at the bottom of the wall base. Substituting the values ​​into the deformation compatibility equation, the initial tension control stress of a single anchor cable is determined through inverse calculation. It is 0.65 times the standard value of tensile strength of steel strand.

[0086] Use 4 jacks, at 0.25%. 50% 75% 100% The anchor cable is tensioned in stages. Each stage is held for 5 minutes, and the elongation value is recorded. After tensioning is completed, the free section of the anchor cable is immediately grouted for sealing and protection.

[0087] Actual measurements using earth pressure cells embedded in the bottom of the wall support showed an average preload stress of 1.48 MPa, which is basically consistent with the design value. With the first line of defense established, the theoretical anti-slip static friction force f=0.35 has exceeded 10000 kN.

[0088] Step 3: Segmented casting of the main well wall Above the wall base, the main body of the well wall is poured in sections from bottom to top, each section being 3 meters high. The construction is carried out in cycles, relying on the pre-loading of the wall base to provide basic anti-slip force.

[0089] Step 4: Pre-reinforcement and load transfer of the dark tunnel entrance At the end of the open channel section, 2 meters from the outline of the designed dark tunnel entrance, a ring-shaped pre-reinforced anchor cable arch is constructed. Sixteen bundles of prestressed anchor cables of the same specifications as the wall base are used.

[0090] The anchor cables, starting from the end of the well wall, are driven obliquely into the rock mass in four directions—forward, upward, left, and right—in an umbrella-like shape. The anchor cables near the top arch have a smaller inclination angle, focusing on controlling top unloading; the side anchor cables have a larger inclination angle, controlling lateral deformation. The anchor cable length is 12-15 meters, ensuring the anchoring section is located in stable, deep rock mass ahead.

[0091] The ends of all anchor cables pass through a reinforced steel annular tray and are securely connected to steel components pre-embedded at the end of the shaft wall. Before any excavation of the tunnel, the annular anchor cable group is tensioned as a whole, with the tension force of each bundle controlled at 600kN, forming a strong prestressed load-bearing arch. This arch transfers the supporting force that will be borne by the rock mass at the tunnel entrance to the rear shaft wall and the deep, stable rock mass in advance through prestressing.

[0092] Step 5: Full-cycle intelligent monitoring and dynamic closed-loop control Monitoring network deployment: Stress monitoring: Install fiber optic stress sensors on the bottom surface of the composite wall seat and on the pre-reinforced anchor cables at the opening.

[0093] Displacement monitoring: Five automatic total station prisms are installed along the inner side of the well wall to perform automatic three-dimensional displacement scanning.

[0094] Data integration: All data is transmitted in real time to the project department's intelligent analysis and decision-making center via a wireless transmission module. The decision-making center can be an industrial computer and a large display screen.

[0095] Implementation of intelligent control: Model operation: The software built into the decision center continuously runs the downward trend prediction algorithm, which couples and analyzes the real-time monitored stress and displacement data with the geological model and construction progress.

[0096] When the tunnel entrance was excavated to the third cycle using the drill-and-blast method, the system detected a slight subsidence trend of 3 mm per day at two monitoring points on the upper part of the well wall. At the same time, the stress sensors of the three top anchor cables in the pre-reinforced arch frame at the tunnel entrance showed a prestress loss of about 8%.

[0097] The system immediately issued a yellow alert and suggested on the operation interface: perform compensatory tensioning on anchor cables T1, T2, and T3 of the pre-reinforced arch at the opening, restoring the target stress to its initial value. After confirmation by the operator, the corresponding single-hole jack was activated to precisely compensate and tension the designated anchor cables. After compensation was completed, monitoring data showed that the displacement trend immediately stopped and slightly rebounded, and the anchor cable stress returned to the set value.

[0098] The entire process of monitoring, analysis, early warning, decision-making, execution, and feedback is completed in a short period of time, achieving real-time maintenance of the health status of the anti-skid system.

[0099] Through the comprehensive application of this invention, the inclined shaft open trench section project has achieved the following significant effects: From the initial well wall pouring to the excavation of over 20 meters into the tunnel, the cumulative maximum displacement of the well wall was controlled well below the allowable value specified in the standards. During the excavation of the tunnel entrance, no visible cracks were observed in the well wall, achieving a truly smooth and safe transition. The intelligent monitoring system provided an unprecedentedly transparent management interface, making all structural statuses readily apparent and providing a basis for decision-making. Although the initial investment was slightly higher than traditional solutions, it completely avoided the huge economic losses that could result from rework, reinforcement, construction delays, or even safety accidents caused by slippage accidents. The overall cost was actually reduced, resulting in significant social and safety benefits. This embodiment fully verifies the advanced nature, reliability, and practicality of the multi-coordination, proactive pre-control, and intelligent dynamic methods and systems provided by this invention. It offers a complete, efficient, and reliable solution for solving the challenges of constructing open trench sections in inclined wells with large inclination angles and complex geological formations.

[0100] Taking the main inclined shaft project of an iron mine (inclination angle 28°, open channel length 42m) in Embodiment 3 of the present invention as an example, compared with the traditional passive solution of simply increasing the bottom area and setting anti-slip keys: During the construction of this invention, the maximum cumulative displacement of the well wall is ≤5mm, which is much lower than the 15~20mm commonly seen in traditional solutions, and no structural cracks appear. Traditional methods require multiple layers of pouring and waiting for the concrete to reach strength to passively resist slippage, typically taking 45-60 days. This invention, through active preloading, enables continuous and rapid pouring, reducing the actual construction time to only 32 days, a reduction of approximately 30%. While traditional solutions have slightly lower initial material costs (approximately 15% lower), considering the high risks associated with accident handling (such as well wall demolition and reconstruction, grouting reinforcement) and project delays, the overall cost risk is expected to be 30% to 50% higher. The solution of this invention avoids the above risks through proactive pre-control, ensuring "excellence from the first attempt," significantly reducing overall financial risk, and exhibiting extremely high reliability and significant technical and economic efficiency.

[0101] By introducing the deformation compatibility equation, the characteristics of the rock-concrete interface are directly and quantitatively correlated with the prestressing tension value for the first time, providing a scientific basis for the refined design of the active anti-sliding system and avoiding the blindness and safety hazards of traditional experience-based tensioning.

[0102] Example 4

[0103] In an exemplary embodiment of this disclosure, an electronic device capable of implementing the above-described method is also provided.

[0104] Those skilled in the art will understand that various aspects of the present invention can be implemented as systems, methods, or program products. Therefore, various aspects of the present invention can be specifically implemented in the following forms: entirely hardware implementations, entirely software implementations (including firmware, microcode, etc.), or implementations combining hardware and software aspects, collectively referred to herein as “circuits,” “modules,” or “systems.”

[0105] The following reference Figure 2 To describe an electronic device 200 according to this embodiment of the present invention. Figure 2 The electronic device 200 shown is merely an example and should not impose any limitations on the functionality and scope of use of the embodiments of the present invention.

[0106] like Figure 2 As shown, the electronic device 200 is manifested in the form of a general-purpose computing device. The components of the electronic device 200 may include, but are not limited to: at least one processing unit 210, at least one storage unit 220, and a bus 230 connecting different system components (including storage unit 220 and processing unit 210).

[0107] The storage unit stores program code that can be executed by the processing unit 210, causing the processing unit 210 to perform the steps described in the "Exemplary Methods" section of this specification according to various exemplary embodiments of the present invention. For example, the processing unit 210 can perform the following method: S1. Excavating and constructing a funnel-shaped reinforced concrete wall base embedded in stable rock mass at the bottom of the open trench, wherein a prestressed anchor cable anchored to the deep rock mass is preset in the wall base, and prestressing is applied to the anchor cable to pre-compress the wall base with the rock mass; S2. Casting the main body of the well wall in sections from bottom to top on the wall base; S3. Before excavating the entrance of the dark cave, constructing a circumferential pre-reinforced anchor cable arch frame in the rock mass outside the end of the well wall, and applying prestress to the arch frame; S4. Performing dynamic stress compensation on at least one of the prestressed anchor cable, prestressed anchor rod, and pre-reinforced anchor cable arch frame based on real-time monitoring data.

[0108] Storage unit 220 may include readable media in the form of volatile storage units, such as random access memory (RAM) 2201 and / or cache memory 2202, and may further include read-only memory (ROM) 2203.

[0109] Storage unit 220 may also include a program / utility 2204 having a set (at least one) program module 2205, such program module 2205 including but not limited to: operating system, one or more application programs, other program modules and program data, each or some combination of these examples may include an implementation of a network environment.

[0110] Bus 230 can represent one or more of several types of bus structures, including a memory cell bus or memory cell controller, a peripheral bus, a graphics acceleration port, a processing unit, or a local bus using any of the various bus structures.

[0111] Electronic device 200 can also communicate with one or more external devices 100 (e.g., keyboard, pointing device, Bluetooth device, etc.), and with one or more devices that enable a user to interact with electronic device 200, and / or any device that enables electronic device 200 to communicate with one or more other computing devices (e.g., router, modem, etc.). This communication can be performed via input / output (I / O) interface 250. Furthermore, electronic device 200 can also communicate with one or more networks (e.g., local area network (LAN), wide area network (WAN), and / or public networks, such as the Internet) via network adapter 260. As shown, network adapter 260 communicates with other modules of electronic device 200 via bus 230. It should be understood that, although not shown in the figures, other hardware and / or software modules can be used in conjunction with electronic device 200, including but not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data backup storage systems.

[0112] From the above description of the embodiments, those skilled in the art will readily understand that the exemplary embodiments described herein can be implemented by software or by combining software with necessary hardware. Therefore, the technical solutions according to the embodiments of this disclosure can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (such as a CD-ROM, USB flash drive, external hard drive, etc.) or on a network, including several instructions to cause a computing device (such as a personal computer, server, terminal device, or network device, etc.) to execute the method according to the embodiments of this disclosure.

[0113] In exemplary embodiments of this disclosure, a computer-readable storage medium is also provided, on which a program product capable of implementing the methods described above is stored. In some possible embodiments, various aspects of the invention may also be implemented as a program product comprising program code that, when the program product is run on a terminal device, causes the terminal device to perform the steps of the various exemplary embodiments of the invention described in the "Exemplary Methods" section of this specification.

[0114] like Figure 3 As shown, a program product 300 for implementing the above-described method according to an embodiment of the present invention is described. This product may employ a portable compact disc read-only memory (CD-ROM) and include program code, and can run on a terminal device, such as a personal computer. However, the program product of the present invention is not limited thereto. In this document, the readable storage medium may be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device.

[0115] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0116] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0117] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0118] Specific embodiments have been used to illustrate the principles and implementation methods of this invention. The descriptions of the embodiments above are only for the purpose of helping to understand the method and core ideas of this invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this invention. Therefore, the content of this specification should not be construed as a limitation of this invention.

[0119] Those skilled in the art will recognize that the embodiments described herein are intended to help the reader understand the principles of the invention, and should be understood that the scope of protection of the invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific modifications and combinations based on the technical teachings disclosed in this invention without departing from the spirit of the invention, and these modifications and combinations are still within the scope of protection of this invention.

Claims

1. A construction method for preventing slippage of the well wall in an open-cut section of an inclined shaft, characterized in that, Includes the following steps: S1. Excavate and construct a funnel-shaped reinforced concrete wall base embedded in stable rock mass at the bottom of the open trench. The wall base is pre-stressed with a prestressed anchor cable anchored to the deep rock mass, and prestress is applied to the anchor cable to pre-compress the wall base and the rock mass. S2. On the wall base, the main body of the well wall is poured in sections from bottom to top; S3. Before excavating the entrance of the dark cave, a circumferential pre-reinforced anchor cable arch is constructed in the rock mass outside the end of the well wall, and prestress is applied to the arch. S4. Based on real-time monitoring data, dynamic stress compensation is performed on at least one of the prestressed anchor cables and the advanced pre-reinforced anchor cable arch frame to maintain the synergistic anti-slip capability of bottom pre-stressing and opening pre-reinforcement.

2. The construction method for preventing slippage of the well wall in the open trench section of an inclined shaft according to claim 1, characterized in that, The initial tension control stress of the prestressed anchor cable in S1 is determined by calculation based on the elastic modulus of the rock mass and concrete, interface characteristics, and design prestress value, using a deformation compatibility equation. The deformation compatibility equation is as follows: In the formula, The elastic modulus of concrete. The comprehensive elastic modulus of the rock mass. and These represent the effective transfer lengths of prestress in concrete and rock mass, respectively. To design the effective compressive stress that is expected to be transferred to the critical face of the rock mass, To account for the equivalent deformation due to interface roughness and shear dilatation.

3. The construction method for preventing slippage of the well wall in the open trench section of an inclined shaft according to claim 1, characterized in that, In step S3, the advanced pre-reinforced anchor cable arch is composed of multiple prestressed anchor cables arranged in an umbrella-like radial pattern. Its tensioning end is connected to the end structure of the well wall, thereby realizing three-dimensional pre-reinforcement of the rock mass in front of and to the side of the tunnel entrance.

4. The construction method for preventing slippage of the well wall in the open trench section of an inclined shaft according to claim 1, characterized in that, S4 specifically includes: S41. Real-time monitoring of wellbore stress, displacement, and prestress value of anchoring system through sensor network; S42. Based on monitoring data, the sliding driving force prediction model is used to assess the structural stability. S43. When the evaluation results meet the preset quantification threshold, the compensation tension of the specified anchoring element is initiated to realize the closed-loop dynamic control of the anti-slip system.

5. The construction method for preventing slippage of the well wall in the open trench section of an inclined shaft according to claim 1, characterized in that, The sensor network in S41 includes an earth pressure cell deployed on the bottom surface of the wall base, a fiber optic stress sensor on the anchor cable, and a three-dimensional laser displacement scanning prism on the surface of the well wall.

6. The construction method for preventing slippage of the well wall in the open trench section of an inclined shaft according to claim 1, characterized in that, The S42 glide driving force prediction model calculates the total glide driving force using the following formula: in, As the driving force of the overall decline, For the first The wall of the well has its own weight. The inclination angle of the inclined shaft. For construction dynamic load coefficient, For example, is the environmental force, and Fu is the unloading force during the excavation of the tunnel.

7. An intelligent anti-slip system for the wellbore wall of an open-cut section of an inclined shaft for implementing the construction method according to any one of claims 1 to 6, characterized in that, include: The pre-compressed funnel-shaped wall base and the pre-reinforced arch frame at the entrance of the dark hole form an active anti-slip skeleton that works in coordination between the bottom and the entrance. The intelligent control system, which is connected to the active anti-slip skeleton, is used to dynamically compensate and control the prestress of the anchoring system based on monitoring data, so as to maintain the long-term stability of the anti-slip skeleton.

8. The system according to claim 7, characterized in that, The active anti-slip skeleton includes: The first group of prestressed anchor cables is embedded in the funnel-shaped wall base and is spatially radially distributed; A second group of prestressed anchor cables is arranged around the entrance of the dark cave and connected to the end of the well wall at the tensioning end.

9. The system according to claim 7, characterized in that, The intelligent control system includes: The collaborative anti-slip structural module consists of a spatial collaborative force-bearing skeleton composed of a pre-compressed composite wall seat embedded in the bedrock and an advanced pre-reinforced arch frame at the entrance of the dark cave. The global perception and monitoring network consists of a distributed array of fiber optic stress sensors, a three-dimensional laser displacement scanner, and a data acquisition module, used to acquire information on the mechanical state and spatial location of the structure in real time. The intelligent analysis and decision-making module includes a data processing unit, a downward trend prediction algorithm module, a stress compensation decision model and an early warning module. It is used to receive monitoring data, evaluate the structural stability through the algorithm model, and generate stress compensation instructions when needed. The dynamic execution and compensation device includes a re-tensionable prestressed anchor cable, a servo-controlled hydraulic tensioning device and a corresponding control system, which is used to execute the compensation tensioning command issued by the intelligent central hub to achieve closed-loop dynamic control of anti-slip capability.

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