Accident Rescue Risk Early Warning Method and System Based on Real-Time Calculation

Abstract

This invention discloses a method and system for accident rescue risk early warning based on real-time calculation. The method includes: when a collapse accident occurs and rescue is required, acquiring surrounding rock parameters, collapse body parameters, and a expected rescue plan; constructing a finite element model based on the surrounding rock parameters, collapse body parameters, and expected rescue plan, and using the excavation advance of the expected rescue plan as the calculation advance; loading a seepage model onto the finite element model based on the expected groundwater level and initializing the steady-state seepage field, and then performing excavation simulation calculations through the finite element model; performing excavation simulation calculations in each round using the calculation advance; conducting rescue operations according to the expected rescue plan, and adjusting and recalculating the parameters of the finite element model and seepage model based on data detected during the rescue operation; when the calculation result of the finite element model exceeds the warning value, determining that there is a risk in the current rescue operation.

Description

Technical Field

[0001] This invention relates to intelligent rescue technology, specifically to an accident rescue risk early warning method and system based on real-time calculation. Background Technology

[0002] Tunnel collapse rescue faces three deadly risks: secondary collapse, suffocation and poisoning, and machinery getting stuck. The top or side walls may collapse at any time, instantly burying the passage and personnel. Gas, oxygen deficiency, and dust accumulate rapidly in the enclosed space, and rescuers and trapped people may suffocate or be poisoned at any time. The narrow working face restricts the operation of large machinery. Once a fault such as drill bit jamming, cable breakage, or sudden collapse of the shaft wall occurs, the rescue passage will be blocked, leading to the interruption of the rescue or even the increase of casualties.

[0003] Especially when using pipe jacking and shaft construction to open up rescue channels, the surrounding rock conditions at the site may differ from the initial survey data due to changes in the external environment, which can easily lead to an underestimation of the danger and trigger a secondary collapse. Summary of the Invention

[0004] In order to at least overcome the above-mentioned shortcomings in the prior art, the purpose of this application is to provide an accident rescue risk early warning method and system based on real-time calculation.

[0005] In a first aspect, embodiments of this application provide an accident rescue risk early warning method based on real-time calculation, including:

[0006] When a collapse accident occurs and rescue is needed, obtain the surrounding rock parameters, collapse body parameters, and expected rescue plan;

[0007] A finite element model is constructed based on the surrounding rock parameters, collapse body parameters, and expected rescue plan, and the tunneling footage of the expected rescue plan is used as the calculated footage.

[0008] After loading the seepage model onto the finite element model based on the expected groundwater level and initializing the steady-state seepage field, excavation simulation calculations are performed using the finite element model; each round of excavation simulation calculations is performed with the calculated advance.

[0009] Rescue operations are carried out according to the expected rescue plan, and the parameters of the finite element model and the seepage model are adjusted and recalculated based on the data detected during the rescue operation.

[0010] When the calculation results of the finite element model exceed the warning value, it is determined that there is a risk to the current rescue operation.

[0011] In one possible implementation, adjusting the parameters of the seepage model includes:

[0012] When the groundwater level detected during the rescue operation does not match the expected groundwater level, the groundwater level in the seepage model is modified to the groundwater level detected during the rescue operation.

[0013] The definition of "compliant" is: when the difference between the actual detected groundwater level and the expected groundwater level is less than or equal to a predetermined threshold, the two are considered to be "compliant" and no modification to the seepage model is required.

[0014] In one possible implementation, adjusting the parameters of the finite element model includes:

[0015] The maximum actual displacement value of a single excavation advance during the rescue operation is obtained; the maximum actual displacement value is the maximum radial displacement value of the excavated rescue channel under unsupported conditions.

[0016] The parameters of the finite element model are adjusted based on the maximum actual displacement value.

[0017] In one possible implementation, adjusting the parameters of the finite element model includes:

[0018] The contribution ratio of the elastic deformation to the maximum deformation value in the finite element model calculation results is obtained as the elastic contribution ratio.

[0019] The product of the elastic contribution ratio and the maximum actual displacement value is calculated as the actual elastic deformation value.

[0020] The elastic modulus of the elements in the finite element model is corrected based on the actual elastic deformation value, and the internal friction angle and cohesion of the elements in the finite element model are corrected based on the maximum actual displacement value.

[0021] In one possible implementation, adjusting the parameters of the finite element model further includes:

[0022] The adjusted elastic modulus of the corresponding deformed part in the finite element model is calculated based on the actual elastic deformation value, and the adjusted internal friction angle and adjusted cohesion of the corresponding deformed part in the finite element model are calculated based on the maximum actual displacement value.

[0023] The current elastic modulus, current internal friction angle, and current cohesion of the corresponding deformed part of the finite element model are obtained as current parameters, and the ratio of the current parameters to the corresponding adjustment parameters is calculated as the adjustment ratio; the adjustment parameters include adjusting elastic modulus, adjusting internal friction angle, and adjusting cohesion;

[0024] The adjustment ratio of the boundary facing the tunneling direction in the finite element model is set to 1. The adjustment ratio of the element corresponding to the maximum actual displacement value in the finite element model is used as the calculated adjustment ratio. Linear interpolation is performed on the elements between the element and the boundary to obtain the adjustment ratio of each element.

[0025] Adjust the elastic modulus, internal friction angle, and cohesion of each unit according to the calculated adjustment ratio.

[0026] In one possible implementation, the adjusted elastic modulus is calculated according to the following formula:

[0027] ;

[0028] In the formula, E is the adjusted elastic modulus; Let p0 be the Poisson's ratio, R be the tunnel diameter of the rescue channel, p0 be the ground stress at the unit, and u1 be the actual elastic deformation value.

[0029] In one possible implementation, calculating the adjusted internal friction angle and adjusted cohesion of the corresponding deformed part in the finite element model based on the maximum actual displacement value includes:

[0030] Calculate the adjustment ratio corresponding to the elastic modulus, and use this adjustment ratio as the adjustment ratio for cohesion;

[0031] The adjusted cohesion is calculated based on the adjustment ratio of the cohesion and the current cohesion, and the adjusted internal friction angle is calculated using the adjusted cohesion and the maximum actual displacement value.

[0032] In one possible implementation, the adjusted internal friction angle is calculated according to the following formula:

[0033]

[0034] In the formula, E is the adjusted elastic modulus; Let R be the Poisson's ratio, R be the tunnel diameter of the rescue channel, and p0 be the geostress at the unit. To adjust the internal friction angle, c is to adjust the cohesion, u1 is the actual elastic deformation value, and u2 is the maximum actual displacement value.

[0035] In one possible implementation, adjusting and recalculating the parameters of the finite element model includes:

[0036] The finite element model is rolled back to the element state before this round of calculation, and after parameter adjustment, the seepage model with adjusted parameters is loaded for calculation.

[0037] Secondly, this application also provides a method for accident rescue risk early warning based on real-time calculation, including:

[0038] The acquisition unit is configured to acquire surrounding rock parameters, collapsed body parameters, and expected rescue plans when a collapse accident occurs and rescue is needed.

[0039] The modeling unit is configured to construct a finite element model based on the surrounding rock parameters, collapse parameters and expected rescue plan, and to use the tunneling footage of the expected rescue plan as the calculated footage.

[0040] The calculation unit is configured to load a seepage model onto the finite element model based on the expected groundwater level and initialize the steady-state seepage field, and then perform excavation simulation calculations through the finite element model; each round of excavation simulation calculations is performed with the calculation advance.

[0041] The adjustment unit is configured to carry out rescue operations according to the expected rescue plan, and to adjust and recalculate the parameters of the finite element model and the seepage model based on the data detected during the rescue operation.

[0042] The early warning unit is configured to determine that there is a risk to the rescue operation when the calculation result of the finite element model exceeds the warning value.

[0043] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0044] This invention relates to a real-time computation-based accident rescue risk early warning method and system. It can invert parameters in the numerical simulation process using data from on-site detection, thereby making the numerical simulation process more accurate and effectively providing early warning of risks in the accident rescue process, thus effectively improving the safety of the accident rescue process. Attached Figure Description

[0045] The accompanying drawings, which are included to provide a further understanding of embodiments of the invention and form part of this application, do not constitute a limitation thereof. In the drawings:

[0046] Figure 1 This is a schematic diagram of the method steps in an embodiment of this application. Detailed Implementation

[0047] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. It should be understood that the accompanying drawings in this application are for illustrative and descriptive purposes only and are not intended to limit the scope of protection of this application. Furthermore, it should be understood that the schematic drawings are not drawn to scale. The flowcharts used in this application illustrate operations implemented according to some embodiments of this application. It should be understood that the operations in the flowcharts may not be implemented in sequence, and steps without logical contextual relationships may be reversed or implemented simultaneously. In addition, those skilled in the art, guided by the content of this application, may add one or more other operations to the flowcharts, or remove one or more operations from the flowcharts.

[0048] Furthermore, the described embodiments are merely some, not all, of the embodiments of this application. The components of the embodiments of this application described and illustrated herein can typically be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0049] Please refer to the following: Figure 1 This is a flowchart illustrating the accident rescue risk warning method based on real-time calculation provided in this embodiment of the invention. Further, the accident rescue risk warning method based on real-time calculation may specifically include the contents described in steps S1-S5.

[0050] S1: When a collapse accident occurs and rescue is needed, obtain the surrounding rock parameters, collapse body parameters and expected rescue plan;

[0051] S2: Construct a finite element model based on the surrounding rock parameters, collapse body parameters and expected rescue plan, and use the tunneling footage of the expected rescue plan as the calculated footage;

[0052] S3: After loading the seepage model onto the finite element model according to the expected groundwater level and initializing the steady-state seepage field, excavation simulation calculations are performed using the finite element model; each round of excavation simulation calculations is performed with the calculated advance.

[0053] S4: Carry out rescue operations according to the expected rescue plan, and adjust and recalculate the parameters of the finite element model and the seepage model based on the data detected during the rescue operation;

[0054] S5: When the calculation result of the finite element model exceeds the warning value, it is determined that there is a risk of rescue operation.

[0055] In implementing this application's embodiments, a preliminary rescue plan needs to be constructed based on prior local survey data and data from surveys of the collapsed body at the time of the collapse. It should be understood that after the anticipated rescue plan is formulated, a risk assessment is generally required. Only high-risk rescue plans, such as shaft rescue and pipe jacking rescue, require risk warnings through this application. A finite element model can be constructed based on the surrounding rock parameters and collapsed body parameters. When dividing the finite element model, the excavation and tunneling progress of the rescue plan needs to be considered. For example, when using shaft rescue, it is necessary to pre-construct the units of the shaft excavation area and the units of the supporting steel pipes to facilitate subsequent unit hiding and unit attribute changes to achieve excavation simulation.

[0056] In this embodiment, tunnel and mountain collapses are likely to be accompanied by drastic changes in weather conditions, such as heavy rain, leading to fluctuations in the groundwater level. This fluctuation is a dynamic process, requiring a seepage model to simulate and address it. Initially, a steady-state seepage field initialization using the seepage model is necessary before excavation simulation calculations. It should be understood that the finite element model requires multiple rounds of excavation simulation. Each round of simulation must simulate the stress-strain state of the surrounding rock after one round of excavation. Furthermore, the calculation of the support structure under the support condition must be performed after each round of excavation. The calculation advance of the finite element model can generally be consistent with the actual excavation advance, or it can be segmented for calculation simulation when the actual excavation advance is long. For example, in shaft construction, if the excavation advance is 50cm, a 50cm long steel cylinder is used for support, and the calculation advance can be 50cm. However, if the excavation advance is 100cm, the calculation advance can still be 50cm, and the support structure is added only after two rounds of calculations.

[0057] In this embodiment, when conducting rescue operations according to the anticipated rescue plan, the convergence data of the surrounding rock and groundwater level around the rescue channel can be monitored. This data can be used to correct the finite element model and seepage model, thereby ensuring the accuracy of the calculation results. After each round of construction progress, the finite element model and seepage model can be corrected and recalculated. The corrected finite element model is better suited for predicting construction results. It should be understood that the calculation of the finite element model should precede the actual rescue construction by at least one advance in order to accurately predict the risks of the rescue construction.

[0058] In one possible implementation, adjusting the parameters of the seepage model includes:

[0059] When the groundwater level detected during the rescue operation does not match the expected groundwater level, the groundwater level in the seepage model is modified to the groundwater level detected during the rescue operation.

[0060] Meeting the criteria: When the difference between the actual detected groundwater level and the expected groundwater level is less than or equal to a predetermined threshold (e.g., ±10cm, ±5%), the two can be considered to "meet the criteria", and no modification to the seepage model is required.

[0061] Discrepancy: When the difference between the actual groundwater level and the expected groundwater level exceeds this predetermined threshold, it is considered a "groundwater level discrepancy." In this case, the groundwater level in the seepage model needs to be adjusted to the actual detected groundwater level. This threshold can be set according to the specific application scenario and engineering requirements.

[0062] Specifically, during rescue operations, the groundwater level detected in real time by sensors is compared with the expected groundwater level (predicted based on models or historical data).

[0063] If the difference between the detected groundwater level and the expected groundwater level exceeds the set threshold, it is considered that the groundwater level is inconsistent, and the parameters of the seepage model are adjusted to make the model reflect the actual situation.

[0064] If the difference is less than the threshold, the groundwater level can be considered "compliant" and no adjustment is needed.

[0065] Threshold setting example: Assume the expected groundwater level is 10 meters. If the actual detected groundwater level is 10.2 meters, and the set tolerance is ±0.1 meters (i.e., 10 meters ± 0.1 meters), the difference is 0.2 meters, exceeding the set threshold. In this case, it is considered "inconsistent," and the model needs adjustment. If the detected groundwater level is 10.05 meters, the difference is only 0.05 meters, below the tolerance range, therefore it is considered "compliant," and no model adjustment is required.

[0066] In the implementation of this application embodiment, the parameter adjustment of the seepage model is mainly the adjustment of the groundwater level, which can be corrected according to the changes in the groundwater level during the excavation process.

[0067] In one possible implementation, adjusting the parameters of the finite element model includes:

[0068] The maximum actual displacement value of a single excavation advance during the rescue operation is obtained; the maximum actual displacement value is the maximum radial displacement value of the excavated rescue channel under unsupported conditions.

[0069] The parameters of the finite element model are adjusted based on the maximum actual displacement value.

[0070] In the implementation of this application embodiment, the maximum actual displacement value is the maximum radial displacement generated in the excavated area within the rescue passage during an unsupported excavation advance. It can characterize the surrounding rock condition of the excavated area. Comparing the maximum actual displacement value with the displacement value calculated by the finite element model can provide a reference for modifying the parameters of the finite element model.

[0071] In one possible implementation, adjusting the parameters of the finite element model includes:

[0072] The contribution ratio of the elastic deformation to the maximum deformation value in the finite element model calculation results is obtained as the elastic contribution ratio.

[0073] The product of the elastic contribution ratio and the maximum actual displacement value is calculated as the actual elastic deformation value.

[0074] The elastic modulus of the elements in the finite element model is corrected based on the actual elastic deformation value, and the internal friction angle and cohesion of the elements in the finite element model are corrected based on the maximum actual displacement value.

[0075] In the implementation of this application's embodiments, the maximum actual displacement value is generally the displacement value after elastoplastic deformation. By extracting the proportion of elastic deformation from the finite element model, it can be used as the proportion of elastic deformation in the maximum actual displacement value. For example, by extracting the equivalent elastic strain and equivalent plastic strain of the element at the corresponding location, and then calculating the ratio of the equivalent elastic strain to the sum of the equivalent elastic strain and equivalent plastic strain, the elastic contribution ratio is formed.

[0076] By analyzing the actual elastic deformation value within the maximum actual displacement value, the elastic modulus corresponding to that location can be directly calculated. This elastic modulus is then assigned to the corresponding elements in the finite element model, allowing for the correction of the elastic modulus for these elements. It should be understood that the elastic modulus correction for the surrounding rock, as a whole region, also requires a global correction. After obtaining the corrected elastic modulus, the internal friction angle and cohesion can be calculated and corrected based on the analytical solution corresponding to the maximum actual displacement value.

[0077] In one possible implementation, adjusting the parameters of the finite element model further includes:

[0078] The adjusted elastic modulus of the corresponding deformed part in the finite element model is calculated based on the actual elastic deformation value, and the adjusted internal friction angle and adjusted cohesion of the corresponding deformed part in the finite element model are calculated based on the maximum actual displacement value.

[0079] The current elastic modulus, current internal friction angle, and current cohesion of the corresponding deformed part of the finite element model are obtained as current parameters, and the ratio of the current parameters to the corresponding adjustment parameters is calculated as the adjustment ratio; the adjustment parameters include adjusting elastic modulus, adjusting internal friction angle, and adjusting cohesion;

[0080] The adjustment ratio of the boundary facing the tunneling direction in the finite element model is set to 1. The adjustment ratio of the element corresponding to the maximum actual displacement value in the finite element model is used as the calculated adjustment ratio. Linear interpolation is performed on the elements between the element and the boundary to obtain the adjustment ratio of each element.

[0081] Adjust the elastic modulus, internal friction angle, and cohesion of each unit according to the calculated adjustment ratio.

[0082] In the implementation of this application embodiment, after calculating the adjusted elastic modulus, adjusted internal friction angle, and adjusted cohesion, the corresponding adjustment ratios can be obtained. To synchronously adjust other elements in the finite element model, it is necessary to obtain the excavation direction of the rescue tunnel in the finite element model and ensure that the parameters of the boundary towards which the excavation direction faces remain consistent with the initial state. At this time, the adjustment ratios of all elements from the element corresponding to the maximum actual displacement value to the boundary can be calculated using linear interpolation, ensuring the continuity of the parameters of the entire model. It should be understood that in this application embodiment, the adjustment of element parameters is not an adjustment of a single element parameter, but rather an adjustment of elements within a range. For example, during a vertical shaft rescue, if the diameter of the excavated shaft is 150cm, after modeling, all elements within a 150cm range from the center point of the shaft can be selected as the elements requiring parameter adjustment, including elements that will be excavated later and elements within a range equal to one shaft diameter outside the shaft. Similarly, during adjustment, each adjustment ratio corresponds to a group of elements on the same horizontal or vertical plane. In the specific adjustment process, parameter adjustment can be performed by constructing an adjustment coefficient matrix.

[0083] In one possible implementation, the adjusted elastic modulus is calculated according to the following formula:

[0084] ;

[0085] In the formula, E is the adjusted elastic modulus; Let p0 be the Poisson's ratio, R be the tunnel diameter of the rescue channel, p0 be the ground stress at the unit, and u1 be the actual elastic deformation value.

[0086] In the implementation of the embodiments of this application, when calculating and adjusting the elastic modulus, the elastic modulus can be calculated based on the analytical solution of elastic deformation.

[0087] In one possible implementation, calculating the adjusted internal friction angle and adjusted cohesion of the corresponding deformed part in the finite element model based on the maximum actual displacement value includes:

[0088] Calculate the adjustment ratio corresponding to the elastic modulus, and use this adjustment ratio as the adjustment ratio for cohesion;

[0089] The adjusted cohesion is calculated based on the adjustment ratio of the cohesion and the current cohesion, and the adjusted internal friction angle is calculated using the adjusted cohesion and the maximum actual displacement value.

[0090] In the implementation of this application, the change in cohesion is calculated using the change in elastic modulus. The reason is that for the surrounding rock, its cohesion is affected not only by its initial change but also by the groundwater level. The initial change in cohesion and the change in elastic modulus can generally be considered to have a linear relationship. The additional change in cohesion can be reflected in the calculation through the seepage model by correcting for the groundwater level.

[0091] In one possible implementation, the adjusted internal friction angle is calculated according to the following formula:

[0092]

[0093] In the formula, E is the adjusted elastic modulus; Let R be the Poisson's ratio, R be the tunnel diameter of the rescue channel, and p0 be the geostress at the unit. To adjust the internal friction angle, c is to adjust the cohesion, and u2 is the maximum actual displacement value.

[0094] In implementing the embodiments of this application, the internal friction angle can be calculated using the analytical solution of the elastoplastic deformation of a single hole under the Mohr-Coulomb criterion. It should be understood that when the adjustment modulus of elasticity and the adjustment cohesion are known, the above equation is equivalent to a transcendental equation for adjusting the internal friction angle, and a numerical solution can be obtained by iterating the equation using the current internal friction angle as initial data.

[0095] In one possible implementation, adjusting and recalculating the parameters of the finite element model includes:

[0096] The finite element model is rolled back to the element state before this round of calculation, and after parameter adjustment, the seepage model with adjusted parameters is loaded for calculation.

[0097] Based on the same inventive concept, this application also provides a method for accident rescue risk early warning based on real-time calculation, including:

[0098] The acquisition unit is configured to acquire surrounding rock parameters, collapsed body parameters, and expected rescue plans when a collapse accident occurs and rescue is needed.

[0099] The modeling unit is configured to construct a finite element model based on the surrounding rock parameters, collapse parameters and expected rescue plan, and to use the tunneling footage of the expected rescue plan as the calculated footage.

[0100] Commonly used finite element analysis software such as ANSYS, ABAQUS, and COMSOL can be used to build finite element models of geological structures. In this embodiment, a specialized underground structure simulation software or a custom MATLAB / Simulink program is used to build the finite element model.

[0101] Define the material model and boundary conditions:

[0102] Surrounding rock parameters: These include the physical and mechanical properties of the surrounding rock, such as elastic modulus, Poisson's ratio, density, internal friction angle, cohesion, etc. These parameters can be obtained from underground geological exploration reports.

[0103] Collapse parameters include the initial geometry, physical properties (such as density and strength), and rheological properties (such as flow behavior in the plastic zone) of the collapsed body.

[0104] Expected rescue plan: including rescue progress, excavation depth, support type, and expected operation route and construction steps.

[0105] The surrounding rock parameters and the parameters of the collapsed body can be input into the finite element model as the mechanical properties of the material. The excavation advance in the expected rescue plan will affect the excavated area in the finite element model. By simulating the excavation progress, the stress, displacement and other field variables in the model can be updated.

[0106] Mesh generation: Mesh generation is performed based on the actual shape of the tunnel or shaft. To ensure the accuracy of the calculation, a finer mesh can be used to further refine complex areas (such as support areas and tunnel junctions), while a coarser mesh can be used in more regular areas or areas without critical changes.

[0107] The boundary conditions of the model should be set, including the effects of fixed supports, applied loads, groundwater level, and seismic loads. Groundwater level and support loads need to be set in combination with actual survey data and expected rescue plans.

[0108] Initial conditions for surrounding rock and collapsed body:

[0109] Based on the survey data, parameters of the surrounding rock and the collapsed body are used to determine the physical and mechanical properties of the entire area. For example, the strength, stiffness, and frictional properties of the surrounding rock need to be obtained from the geological exploration report, while parameters of the collapsed body (such as the degree of soil looseness and soil particle size) will affect the rheological model of the soil.

[0110] Introduction of rescue plan: The excavation advance in the expected rescue plan determines the excavation progress of each round of simulation. For example, during the rescue process, each advance (such as excavating 50cm each time) will update the surrounding rock stress field and displacement field in the finite element model. This advance data can be obtained from the rescue plan, usually based on the time schedule and construction area of ​​the preliminary design.

[0111] Dynamic updates and feedback: During actual rescue operations, model parameters can be adjusted in real time based on detection data (such as surrounding rock displacement and groundwater level). Especially during excavation, new real-time data will influence model updates, ensuring that simulation results more closely reflect actual operational conditions.

[0112] The anticipated rescue plan is based on the following information:

[0113] Rescue mission: Define the rescue objectives (e.g., clearing a path, moving equipment);

[0114] Rescue progress: Determine the progress of the rescue work, including excavation advance and support progress. The advance can be based on the preliminary design and survey data, or dynamically adjusted according to the actual situation during the rescue operation.

[0115] Work steps: Specific excavation work steps, including how to excavate, how to support, and how to handle water levels.

[0116] Anticipated rescue plans typically come from the following aspects:

[0117] Preliminary survey and design plan: Based on the geological survey data, construction drawings and design plans from the early stages of the project, a preliminary rescue plan is determined.

[0118] Historical data: Based on the operational experience of similar historical cases, develop a preliminary operational plan to ensure safety during the rescue process.

[0119] On-site monitoring data: Real-time acquisition of on-site data, such as changes in surrounding rock, changes in groundwater level, air quality, etc., and adjustment of rescue plans based on actual data.

[0120] The calculation unit is configured to load a seepage model onto the finite element model based on the expected groundwater level and initialize the steady-state seepage field, and then perform excavation simulation calculations through the finite element model; each round of excavation simulation calculations is performed with the calculation advance.

[0121] The adjustment unit is configured to carry out rescue operations according to the expected rescue plan, and to adjust and recalculate the parameters of the finite element model and the seepage model based on the data detected during the rescue operation.

[0122] The early warning unit is configured to determine that there is a risk to the rescue operation when the calculation result of the finite element model exceeds the warning value.

[0123] The specific components and implementation methods of the seepage model are as follows:

[0124] 1. Components of a seepage model:

[0125] In this embodiment, the seepage model is used to simulate the behavior of groundwater flow. Given changes in groundwater level, the seepage model needs to accurately simulate groundwater flow and adjust the calculation results of the finite element model according to the changes in water level.

[0126] The components of a seepage model include the following aspects:

[0127] Fluid dynamics equations: The core of the seepage model is to describe the flow of water in soil using fluid dynamics equations. A commonly used equation is Darcy's law, which describes the relationship between water velocity and soil porosity, permeability, and water pressure gradient.

[0128]

[0129] Where Q is the water flow velocity, k is the soil permeability coefficient, and A is the flow cross-sectional area. The pressure gradient is represented by ΔP, which indicates the pore water pressure difference between two adjacent calculation points (or the centers of two adjacent finite element elements) along the direction of groundwater flow, in Pa; Δx represents the spatial distance between the two corresponding calculation points in that direction, in meters, and Δx is not equal to 0.

[0130] Permeability coefficient (k): The permeability coefficient of soil is a parameter describing the permeability of soil or rock, usually determined based on geological exploration or experimental data. The permeability coefficient k is a key parameter in seepage models, affecting the flow velocity of groundwater.

[0131] Groundwater level (P): Changes in groundwater level are one of the key boundary conditions in seepage models. Changes in water level directly affect the rate and direction of seepage.

[0132] Porosity and flow path: The porosity of soil determines the path of water flow. Seepage models need to simulate the flow path and velocity based on the soil porosity distribution.

[0133] Boundary conditions: To ensure that the calculation of the seepage model conforms to actual working conditions, certain boundary conditions need to be set. Boundary conditions include: groundwater level, such as the initial groundwater level; inflow / outflow, the area where groundwater enters or flows out; and fixed boundaries, such as the groundwater level not exceeding a certain specific value.

[0134] 2. Implementation method of seepage model, detailed steps of seepage model loading and simulation:

[0135] Step 1: Obtain the initial conditions for the seepage model:

[0136] Geological exploration and parameter acquisition: Based on exploration data, obtain physical parameters such as permeability (k) and porosity of soil or rock. Obtain initial state data of groundwater level and set the initial water level for groundwater flow.

[0137] Soil model establishment: A soil permeability model is constructed using geological data, exploration reports, and historical data to determine the soil permeability. The permeability coefficient and porosity are used as input parameters, and a seepage model is established based on actual geological conditions.

[0138] Step 2: Load the seepage model into the finite element model:

[0139] Seepage calculation based on Darcy's law: The parameters of the seepage model (such as permeability coefficient and groundwater level) are used as input, and the water flow is calculated using Darcy's law. For each finite element element, the flow rate of the fluid in each element is calculated based on the water pressure gradient, soil permeability, and porosity.

[0140] Coupling with the Finite Element Model: The calculation results of the seepage model (such as water flow rate and groundwater level changes) need to be coupled with the finite element model. In the finite element model calculations, the seepage model affects the stress field and displacement field of the soil. Through iterative calculations, the groundwater flow state of each round of excavation is updated to ensure that the impact of seepage on soil deformation is accurately calculated.

[0141] Step 3: Initialization and Steady-State Analysis of Seepage Field

[0142] Steady-state seepage field initialization: In the initial stage, the seepage field is initialized in a steady state using the expected groundwater level. Initialization of the seepage field involves calculating the water flow distribution and groundwater level under steady-state conditions. The model is initialized by setting initial conditions for the finite element model (such as a fixed water level or given water inflow conditions) to ensure that the initial state of the seepage model matches the actual situation.

[0143] Steady-state analysis: Steady-state seepage field analysis is performed to ensure that groundwater flow conforms to actual groundwater level changes. Through multiple rounds of simulation calculations, the seepage model can accurately reflect the fluctuations of the actual groundwater level. In each round of simulation calculations, the seepage model adjusts the water flow based on new groundwater level data and updates the pressure distribution in the model.

[0144] Step 4: Adjust the seepage model in real time:

[0145] During rescue operations, the actual groundwater level is obtained through real-time monitoring equipment based on on-site groundwater level change data. The expected groundwater level is compared with the actual groundwater level; if a significant difference exists, the seepage model is adjusted. This involves updating the water level parameters in the seepage model to more closely approximate the actual situation.

[0146] Dynamic feedback: After each round of excavation simulation calculations, the results of the seepage model are adjusted based on the actual situation. By providing real-time feedback on changes in groundwater level, the finite element model is ensured to reflect the most realistic geological and hydrological conditions, reducing the risks caused by inaccurate parameters.

[0147] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0148] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative. For instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed may be indirect coupling or communication connection through some interfaces, devices or units, or may be electrical, mechanical or other forms of connection.

[0149] The units described as separate components may or may not be physically separate. As will be apparent to those skilled in the art, the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0150] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0151] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or grid device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0152] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A real-time calculation-based accident rescue risk early warning method, characterized in that, include: When a collapse accident occurs and rescue is needed, obtain the surrounding rock parameters, collapse body parameters, and expected rescue plan; A finite element model is constructed based on the surrounding rock parameters, collapse body parameters, and expected rescue plan, and the tunneling footage of the expected rescue plan is used as the calculated footage. After loading the seepage model onto the finite element model based on the expected groundwater level and initializing the steady-state seepage field, excavation simulation calculations are performed using the finite element model; each round of excavation simulation calculations is performed with the calculated advance. Rescue operations are carried out according to the expected rescue plan, and the parameters of the finite element model and the seepage model are adjusted and recalculated in real time based on the data detected during the rescue operation. This includes: obtaining the maximum actual displacement value of a single excavation advance during the rescue operation; the maximum actual displacement value is the maximum radial displacement value of the excavated rescue channel under unsupported conditions; adjusting the parameters of the finite element model based on the maximum actual displacement value; obtaining the contribution ratio of elastic deformation of the maximum deformation value in the finite element model calculation results as the elastic contribution ratio; calculating the product of the elastic contribution ratio and the maximum actual displacement value as the actual elastic deformation value; correcting the elastic modulus of the elements in the finite element model based on the actual elastic deformation value; and correcting the internal friction angle and cohesion of the elements in the finite element model based on the maximum actual displacement value. The finite element model and the seepage model are corrected and recalculated after each round of construction advance. When the calculation results of the finite element model exceed the warning value, it is determined that there is a risk to the current rescue operation.

2. The accident rescue risk early warning method based on real-time calculation according to claim 1, characterized in that, Adjusting the parameters of the seepage model includes: When the groundwater level detected during the rescue operation does not match the expected groundwater level, the groundwater level in the seepage model is modified to the groundwater level detected during the rescue operation. The definition of "compliant" is: when the difference between the actual detected groundwater level and the expected groundwater level is less than or equal to a predetermined threshold, the two are considered to be "compliant" and no modification to the seepage model is required.

3. The accident rescue risk early warning method based on real-time calculation according to claim 1, characterized in that, Adjusting the parameters of the finite element model also includes: The adjusted elastic modulus of the corresponding deformed part in the finite element model is calculated based on the actual elastic deformation value, and the adjusted internal friction angle and adjusted cohesion of the corresponding deformed part in the finite element model are calculated based on the maximum actual displacement value. The current elastic modulus, current internal friction angle, and current cohesion of the corresponding deformed part of the finite element model are obtained as current parameters, and the ratio of the current parameters to the corresponding adjustment parameters is calculated as the adjustment ratio; the adjustment parameters include adjusting elastic modulus, adjusting internal friction angle, and adjusting cohesion; The adjustment ratio of the boundary facing the tunneling direction in the finite element model is set to 1. The adjustment ratio of the element corresponding to the maximum actual displacement value in the finite element model is used as the calculated adjustment ratio. Linear interpolation is performed on the elements between the element and the boundary to obtain the adjustment ratio of each element. Adjust the elastic modulus, internal friction angle, and cohesion of each unit according to the calculated adjustment ratio.

4. The accident rescue risk early warning method based on real-time calculation according to claim 3, characterized in that, The adjusted elastic modulus is calculated according to the following formula: ； In the formula, E is the adjusted elastic modulus; Let p0 be Poisson's ratio, R be the diameter of the rescue passage, p0 be the ground stress at the unit, and u1 be the actual elastic deformation value.

5. The accident rescue risk early warning method based on real-time calculation according to claim 3, characterized in that, The calculation of the adjusted internal friction angle and adjusted cohesion of the corresponding deformed part in the finite element model based on the maximum actual displacement value includes: Calculate the adjustment ratio corresponding to the elastic modulus, and use this adjustment ratio as the adjustment ratio for cohesion; The adjusted cohesion is calculated based on the adjustment ratio of the cohesion and the current cohesion, and the adjusted internal friction angle is calculated using the adjusted cohesion and the maximum actual displacement value.

6. The accident rescue risk early warning method based on real-time calculation according to claim 5, characterized in that, The adjusted internal friction angle is calculated according to the following formula: ； In the formula, E is the adjusted elastic modulus; Let R be the Poisson's ratio, R be the diameter of the rescue passage, and p0 be the ground stress at the unit. To adjust the internal friction angle, c is to adjust the cohesion, u1 is the actual elastic deformation value, and u2 is the maximum actual displacement value.

7. The accident rescue risk early warning method based on real-time calculation according to claim 1, characterized in that, Adjusting and recalculating the parameters of the finite element model includes: The finite element model is rolled back to the element state before this round of calculation, and after parameter adjustment, the seepage model with adjusted parameters is loaded for calculation.

8. An accident rescue risk early warning system based on real-time calculation using the method described in any one of claims 1 to 7, characterized in that, include: The acquisition unit is configured to acquire surrounding rock parameters, collapsed body parameters, and expected rescue plans when a collapse accident occurs and rescue is needed. The modeling unit is configured to construct a finite element model based on the surrounding rock parameters, collapse parameters and expected rescue plan, and to use the tunneling footage of the expected rescue plan as the calculated footage. The calculation unit is configured to load a seepage model onto the finite element model based on the expected groundwater level and initialize the steady-state seepage field, and then perform excavation simulation calculations through the finite element model; each round of excavation simulation calculations is performed with the calculation advance. The adjustment unit is configured to carry out rescue operations according to the expected rescue plan, and to adjust and recalculate the parameters of the finite element model and the seepage model based on the data detected during the rescue operation. The early warning unit is configured to determine that there is a risk to the rescue operation when the calculation result of the finite element model exceeds the warning value.

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