A disaster modeling method for ultra-deep shaft engineering in metal mines

Abstract

The present application provides a method for modeling engineering disasters of ultra-deep vertical shafts in metal mines, belonging to the technical field of engineering modeling of ultra-deep vertical shafts in metal mines. The method comprises establishing an ultra-deep vertical shaft geological model based on the engineering geological information of the well construction area; establishing an ultra-deep vertical shaft engineering property model based on the dominant structural surface group, rock physical and mechanical parameters, and wellbore rock mechanical parameters; establishing an ultra-deep vertical shaft numerical model based on dynamic response characteristics and local stability evaluation parameters; and establishing an ultra-deep vertical shaft engineering disaster comprehensive model based on the ultra-deep vertical shaft geological model, the ultra-deep vertical shaft engineering property model, and the ultra-deep vertical shaft numerical model. By constructing a comprehensive engineering disaster model, the rock formation information at different depths of the wellbore through the formation and the spatial position relationship between the geological anomaly and the ultra-deep vertical shaft are reflected, the mechanical mechanism of ground pressure disasters induced by ultra-deep vertical shaft construction is studied, and a criterion for ultra-deep wellbore disaster-causing displacement is formed, providing a scientific basis for early warning and accident prevention and control.

Description

Technical Field

[0001] The present application belongs to the technical field of ultra-deep shaft engineering modeling in metal mines, and specifically relates to a method for modeling disasters in ultra-deep shaft engineering in metal mines. Background Art

[0002] As mine construction continues to deepen, the complexity of the strata traversed by ultra-deep shafts increases. Deep rock masses are subject to high geostress, high confined water, high rock temperatures, and nonlinear dynamic loads, resulting in fundamentally different failure modes from those of shallow rock masses. The geological structure and stress accumulation-migration-release patterns of the surrounding rock mass result in deformation and failure characteristics, triggering conditions, dynamic response characteristics, and manifestation characteristics that differ from those of shallow shaft surrounding rock. Therefore, the deformation and failure of ultra-deep shafts are inextricably linked to their engineering geological environment, engineering dynamics, and the interactions between them. Shaft deformation and failure are influenced by natural factors such as the engineering geology, hydrogeology, geostress conditions, rock mass properties, groundwater, and temperature changes at the shaft location, as well as by engineering factors such as excavation disturbances and lifting dynamic loads. Currently, shaft deformation, instability, and damage are common problems both domestically and internationally. For example, at Australia's Mount Isa Copper Mine, shaft deformation and damage were caused by faults and mining sequences. At the Xiaoguanzhuang Iron Mine in Shandong Province, both the main and auxiliary shafts deviated due to mining activity. At the Jinchuan No. 2 Mine, an under-construction shaft collapsed immediately after being installed, affected by rock formation structure and horizontal geostress. At the Wangershan Gold Mine in Shandong Province, shaft wall damage also occurred due to rock formation properties and mining stress. At the Xuzhuang Mine in the Datun Mining Area in Jiangsu Province, the auxiliary shaft suffered two shaft fractures due to additional stress in the surrounding rock. Once a shaft is deformed or damaged, it directly impacts normal hoisting, severely restricting safe mine production.

[0003] The lack of transparency in geological information in the construction area is a major constraint on the safe and efficient construction of ultra-deep vertical shafts. With the surge in demand for deep mineral resource development, traditional geological exploration and shaft design methods face significant challenges in addressing the complex "three highs" (high geostress, high seepage pressure, and high geotemperature) environment of kilometer-scale vertical shaft projects. Deep mining geological environments exhibit significant multi-scale and multi-field coupling: The combined effects of high geostress, high seepage pressure, and tectonic movement create a complex structure of interwoven joints, faults, and alteration zones. Stratigraphic lithology exhibits heterogeneous distribution due to magmatic intrusion or metamorphism, and groundwater systems dynamically interact with geothermal fields. For example, the mylonite zone uncovered at a depth of 3,000 meters in the Mponego gold mine in South Africa exhibits a permeability gradient of three orders of magnitude, while the spatial coupling between the deep rockburst-prone zone and concealed faults in the Escondida copper mine in Chile exceeds 80%. This complexity requires that 3D geological modeling technology transcend the limitations of static stratigraphic divisions and achieve the coordinated characterization of geological structure, physical parameters, and dynamic processes. As the core support for intelligent mining, stratum transparency technology aims to achieve precise visualization of underground rock structure, geological formations, hydrological conditions, and responses to engineering disturbances through multi-source sensing, data fusion, and dynamic modeling, providing a scientific basis for decision-making in safe and efficient shaft construction. The future direction of development will be to strengthen research on the informatization, visualization, and intelligentization of ultra-deep shaft construction, operation, and maintenance, and gradually achieve safer, higher-quality, more efficient, and more intelligent construction and management of ultra-deep shafts. Summary of the Invention

[0004] Therefore, the technical problem to be solved in this application is to provide a method for modeling engineering disasters in ultra-deep vertical shafts in metal mines, which can reflect the rock formation information and the spatial position relationship between geological anomalies and ultra-deep vertical shafts at different depths of the stratum through which the wellbore passes by by constructing a comprehensive engineering disaster model, study the mechanical mechanism of ground pressure disasters induced by ultra-deep vertical shaft construction, form a criterion for disaster-causing displacement of ultra-deep wellbores, and analyze key parameters such as the surrounding rock damage morphology and damage depth, providing a scientific basis for early warning and accident prevention and control.

[0005] To solve the above problems, this application provides a method for modeling engineering disasters in ultra-deep shafts of metal mines, including:

[0006] Acquiring engineering geological information of the well construction area, and establishing an ultra-deep vertical shaft geological model based on the engineering geological information of the well construction area;

[0007] Obtaining a dominant structural surface group of surrounding rocks at different depths of an ultra-deep vertical shaft, obtaining rock physical and mechanical parameters, and obtaining wellbore rock mass mechanical parameters; and establishing an ultra-deep vertical shaft engineering property model based on the dominant structural surface group, the rock physical and mechanical parameters, and the wellbore rock mass mechanical parameters;

[0008] Obtaining dynamic response characteristics and local stability evaluation parameters of the ultra-deep vertical shaft surrounding rock; establishing an ultra-deep vertical shaft numerical model based on the dynamic response characteristics and the local stability evaluation parameters;

[0009] Based on the ultra-deep vertical shaft geological model, the ultra-deep vertical shaft engineering property model and the ultra-deep vertical shaft numerical model, a comprehensive model of ultra-deep vertical shaft engineering disasters is established.

[0010] Optionally, the step of obtaining engineering geological information of the well construction area and establishing a geological model of the ultra-deep vertical shaft based on the engineering geological information of the well construction area includes:

[0011] Conduct engineering geological surveys on the ultra-deep vertical shaft construction area to obtain engineering geological information of the well construction area;

[0012] Based on the engineering geological information of the well construction area, the spatial location of the fault fracture zone and the aquifer is divided, and the spatial interaction relationship between the geological anomaly and the ultra-deep vertical shaft is determined;

[0013] Compile the rock core information of engineering survey holes and divide the ultra-deep vertical shaft engineering survey rock groups based on the rock core information of engineering survey holes;

[0014] Based on the spatial interaction relationship between the geological anomaly and the ultra-deep vertical shaft and the rock formation of the ultra-deep vertical shaft engineering survey, a geological model of the ultra-deep vertical shaft is established.

[0015] Optionally, the aquifer includes a top drainage section, a mining-affected section, and a deep unaffected section.

[0016] Optionally, the rock core information of the engineering exploration holes is cataloged, wherein the rock core information of the exploration holes includes color, degree of weathering, rock structure, distance between structural planes, hardness, rock lithology and occurrence depth.

[0017] Optionally, before the step of establishing a comprehensive model of ultra-deep vertical shaft engineering disasters based on the spatial interaction relationship between the geological anomaly and the ultra-deep vertical shaft and the ultra-deep vertical shaft engineering survey rock formation, the step further includes:

[0018] The deep stratum core information of the excavation working face is cataloged, and the engineering survey hole core information is corrected based on the deep stratum core information of the excavation working face.

[0019] Optionally, the steps of obtaining a dominant structural surface group of surrounding rocks of different depths of an ultra-deep vertical shaft, obtaining rock physical and mechanical parameters, and obtaining wellbore rock mass mechanical parameters; and establishing an ultra-deep vertical shaft engineering property model based on the dominant structural surface group, the rock physical and mechanical parameters, and the wellbore rock mass mechanical parameters include:

[0020] Conduct an underground field survey of the entire ultra-deep shaft excavation process to obtain information on the occurrence of the surrounding rock structure surfaces at different depths of the ultra-deep shaft. Based on this information, determine the dominant structural surface groups of the surrounding rock at different depths.

[0021] Collect rock samples at different depths in ultra-deep shafts, conduct rock mechanics tests, and obtain rock physical and mechanical parameters;

[0022] Classify the rock mass quality levels of surrounding rocks at different depths of the wellbore and calculate the mechanical parameters of the wellbore rock mass using the Hoek-Brown strength criterion;

[0023] An ultra-deep vertical shaft engineering property model is established based on the information of the dominant structural surface group of the wellbore surrounding rock, the rock physical and mechanical parameters, and the wellbore rock mass mechanical parameters.

[0024] Optionally, the rock mechanics test includes a uniaxial compressive strength test, a Brazilian split test and a shear test.

[0025] Optionally, the method for classifying the rock mass quality grades of surrounding rocks at different depths of the wellbore includes adopting the Barton rock mass quality index Q classification method, the rock mass geomechanics RMR classification method and the geological strength index GSI classification method.

[0026] Optionally, the step of obtaining dynamic response characteristics and local stability evaluation parameters of the ultra-deep vertical shaft surrounding rock; and establishing a numerical model of the ultra-deep vertical shaft based on the dynamic response characteristics and local stability evaluation parameters includes:

[0027] Establish a two-dimensional plane model of the shaft section, input rock mass mechanical parameters and ground stress field, and analyze the distribution characteristics of the disturbance stress field, shaft displacement information, and the range of the shaft plastic zone caused by ultra-deep shaft excavation;

[0028] Establish a three-dimensional geometric model of the wellbore section, input the information of the dominant structural surface group of the wellbore surrounding rock to generate a wedge distribution model of the wellbore surrounding rock, and obtain the wedge position and safety factor of the wellbore surrounding rock;

[0029] Based on the distribution characteristic information of the disturbance stress field during the excavation of the ultra-deep vertical shaft, the shaft displacement information, the range information of the shaft plastic zone, and the wedge position and safety factor of the shaft surrounding rock, a numerical model of the ultra-deep vertical shaft is established.

[0030] Optionally, the information of the dominant structural surface group of the wellbore surrounding rock includes geometric and mechanical characteristic parameters of the dominant structural surface group and strength parameters of the dominant structural surface group;

[0031] Among them, the geometric and mechanical characteristic parameters of the advantageous structural surface group include structural surface occurrence, structural surface spacing and continuity parameters; the strength parameters of the advantageous structural surface group include internal friction angle, cohesion and tensile strength.

[0032] By means of the above technical solution, the present invention has at least the following beneficial effects:

[0033] This embodiment of the present application provides a method for modeling engineering hazards in ultra-deep vertical shafts in metal mines. The geological model, centered on a three-dimensional spatial topological structure, integrates the spatial interactions between ultra-deep vertical shafts and geological anomalies (such as tectonic zones, faults, and highly confined aquifers). The engineering property model establishes a quantitative evaluation system for engineering properties based on the correlation analysis of geological and mechanical parameters. The numerical model, based on a numerical simulation platform, quantitatively analyzes the disturbance mechanism of ultra-deep vertical shaft engineering activities on the surrounding rock system. Through multi-model data fusion (the geological model provides boundary conditions, the engineering property model guides design optimization, and the numerical model outputs mechanical responses), a comprehensive model for ultra-deep vertical shaft engineering hazards is constructed, forming criteria for ultra-deep shaft displacement that causes disasters, and analyzing key parameters such as surrounding rock failure morphology and failure depth. This provides a scientific basis for early warning and accident prevention, significantly improving the accuracy of disaster risk prediction and prevention and control capabilities for ultra-deep vertical shaft projects. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a flow chart of a method for modeling disasters in ultra-deep shaft engineering in a metal mine according to an embodiment of the present application;

[0035] Figure 2 The geological model of the ultra-deep vertical shaft according to the embodiment of the present application;

[0036] Figure 3 This is an isodensity map of the surrounding rock structure of the ultra-deep vertical shaft in an embodiment of the present application;

[0037] Figure 4 This is a rose diagram of the rock structure of the ultra-deep vertical shaft in an embodiment of the present application;

[0038] Figure 5 The ultra-deep vertical shaft engineering property model of the embodiment of this application;

[0039] Figure 6 This is a numerical model of an ultra-deep shaft according to an embodiment of the present application;

[0040] Figure 7 This is the wedge-shaped distribution model of the embodiment of the present application;

[0041] Figure 8 This is the disturbance stress field distribution characteristic model of the embodiment of the present application.

[0042] The reference numerals indicate:

[0043] Ⅰ, F1 fault fracture zone; Ⅱ, F3 fault fracture zone; Ⅲ, ultra-deep vertical shaft; Ⅳ, dominant structural surface group. DETAILED DESCRIPTION

[0044] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0045] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature identified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0046] In this application, unless otherwise specified or limited, the terms "mounted," "connected," "connect," "fixed," etc. should be understood broadly. For example, they may refer to fixed connection, detachable connection, or integral connection; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; or internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0047] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0048] The present invention demonstrates a technical method employed during the construction of an auxiliary shaft at a Shandong Gold Group gold mine. This shaft, constructed to a depth of 2,000 meters, is considered an ultra-deep vertical shaft. Shaft deformation and failure are closely related to the engineering geology, engineering dynamics, and the interactions between these environments. Therefore, by establishing a hazard model reflecting the engineering geology of the ultra-deep vertical shaft, the strata under construction are made transparent, hazard risks are proactively predicted, and construction accidents are mitigated.

[0049] The engineering disaster modeling method applied in this application is mainly applicable to ultra-deep vertical shafts with a depth of more than 1,500m. Due to the characteristics of "high well depth", ultra-deep vertical shafts face challenges such as high stratum stress, high aquifer pressure, and complex and changeable geological conditions during the construction process. They are always under the threat of disasters and it is difficult to ensure construction safety. By constructing a comprehensive engineering disaster model to reflect the rock formation information at different depths of the wellbore through the stratum and the spatial position relationship between the geological anomaly and the ultra-deep vertical shaft, the mechanical mechanism of ground pressure disasters induced by ultra-deep vertical shaft construction can be studied, and the criterion for the disaster-causing displacement of ultra-deep wellbore can be formed. It can also determine the key parameters such as the surrounding rock failure morphology and failure depth, providing a scientific basis for early warning and accident prevention and control. The application of this model will help accumulate ultra-deep wellbore engineering data, promote the formation of a core technology system for ultra-deep vertical shaft construction with independent intellectual property rights, and lay the foundation for the formulation of technical standards and specifications for deep vertical shaft construction in my country.

[0050] See also Figure 1 As shown, according to an embodiment of the present application, a method for modeling disasters in ultra-deep shaft engineering of metal mines is provided, comprising:

[0051] Step S1: Acquire engineering geological information of the well construction area and establish an ultra-deep vertical shaft geological model based on the engineering geological information of the well construction area. Specifically, it includes:

[0052] Step S11 : Conducting engineering geological survey on the well construction area of ​​the ultra-deep vertical shaft III to obtain engineering geological information of the well construction area.

[0053] In this embodiment, a multi-scale engineering geological survey is conducted on the ultra-deep vertical shaft III construction area to obtain comprehensive engineering geological information including stratum lithology, geological structure, hydrogeology and geostress distribution.

[0054] Step S12: Based on the engineering geological information of the well construction area, the spatial positions of the fault fracture zone and the aquifer are divided, and the spatial interaction relationship between the geological anomaly and the ultra-deep vertical shaft III is determined.

[0055] Among them, the ultra-deep vertical shaft III construction area includes F1 fault fracture zone I and F3 fault fracture zone II.

[0056] Specifically, the ultra-deep vertical shaft III is located in the footwall of the northwest of the F1 fault fracture zone I. The F1 fault fracture zone I generally strikes northeast, but there is a bend in the middle, resulting in segmented changes in the strike; the bend section strikes about 17°, the average strike to the east is 38°, and the average strike to the west is 58°; the overall inclination is southeast, with an average dip of 46°; the shallow part dips to the northwest, with an inclination of about 70°~80°; and it tends to be normal above 400m.

[0057] The shallow dip angle of the F1 fault fracture zone I varies greatly, which may cause local rock mass fragmentation, so attention should be paid to shallow support.

[0058] Specifically, the F3 fault fracture zone II of the ultra-deep vertical shaft III strikes northwest, ranges from 300° to 310°, dips northeast, and has a dip angle of 80° to 90°. It has good water conductivity and is water-rich.

[0059] Specifically, in this embodiment, strike refers to the extension direction of the fault fracture zone on the horizontal plane, expressed by azimuth; dip refers to the inclination direction of the fault fracture zone; dip refers to the angle between the fault fracture zone and the horizontal plane; hanging wall refers to the upper rock mass as the hanging wall and the lower rock mass as the foot wall when the fault fracture zone is inclined.

[0060] Among them, taking into account the influence of factors such as the recharge and drainage methods of various rock layers at different depths in ultra-deep vertical shafts, the hydraulic characteristics of groundwater, water richness, and location, the aquifer can be divided into the top drainage section, the mining affected section, and the deep unaffected section.

[0061] Step S13: cataloging the engineering survey hole rock core information, and dividing the ultra-deep vertical shaft engineering survey rock groups based on the engineering survey hole rock core information.

[0062] Among them, the core information of engineering survey holes is cataloged, including rock information, structural surface information, structural surface filling information and other information.

[0063] Specifically, rock information includes rock color, degree of weathering, rock structure, spacing between rock structural planes, hardness, rock lithology, and depth of occurrence. Structural plane information includes surface type, opening, presence of fillings, roughness, and occurrence. Structural plane filling information includes water content, color, thickness, continuity, hardness, filling type, and source.

[0064] Among them, the ultra-deep vertical shaft engineering survey rock groups are divided based on the core information of the engineering survey holes. That is to say, according to the rock information, structural surface information and structural surface filling material information, the rock strata within the survey depth range are divided into 13 engineering rock groups from top to bottom, namely: bedrock weathering zone rock group, monzogranite rock group, potash granite rock group, monzogranite rock group, sericite granite rock group, monzogranite rock group, sericite granite rock group, monzogranite rock group, sericite granite rock group, monzogranite rock group, sericite granite cataclasite rock group, monzogranite rock group, lamprophyre rock group, monzogranite rock group, and greisen rock group.

[0065] Step S14: cataloging the deep stratum core information of the excavation working face, and correcting the engineering survey hole core information based on the deep stratum core information of the excavation working face.

[0066] Specifically, during ultra-deep vertical shaft construction, water exploration and grouting are performed over extended sections at each drilling stage (e.g., 120 meters). Coring is performed at the same stage of the shaft excavation face to obtain 120-meter-long core samples. The core samples are cataloged using the core cataloging method in step S13 to correct the core cataloging information for the corresponding depth range of the engineering survey hole. This addresses limitations of the engineering survey stage, reduces construction risks, and improves project safety and economic efficiency.

[0067] Step S15: establishing a geological model of the ultra-deep vertical shaft based on the spatial interaction relationship between the geological anomaly and the ultra-deep vertical shaft and the rock formation of the ultra-deep vertical shaft engineering survey.

[0068] Specifically, a 3D cylindrical model of the shaft, a fault fracture zone model, an aquifer model, and an engineering survey rock formation model were constructed using Rhino modeling software. These models were then fitted to the 3D cylindrical model to create a geological model for the ultra-deep shaft. The fault fracture zone model and the engineering survey rock formation model were adjusted based on core data collected from the tunneling face during the construction phase, updating the geological model of the ultra-deep shaft.

[0069] like Figure 2 As shown in the figure, the ultra-deep vertical shaft geological model established by Rhino software intuitively displays the spatial relationship between the wellbore, fault fracture zone, aquifer and engineering survey rock group, providing a scientific basis for grouting, support and tunneling.

[0070] Step S2: Obtain the dominant structural surface group IV of the surrounding rock of the ultra-deep vertical shaft at different depths, obtain the rock physical and mechanical parameters, and obtain the rock mass mechanical parameters; and establish an ultra-deep vertical shaft engineering property model based on the dominant structural surface group IV, the rock physical and mechanical parameters, and the rock mass mechanical parameters.

[0071] Step S21: Conduct an underground field survey of the entire ultra-deep vertical shaft excavation process to obtain the occurrence information of the wellbore surrounding rock structure surface at different depths of the ultra-deep vertical shaft. Based on the occurrence information of the wellbore surrounding rock structure surface at different depths of the ultra-deep vertical shaft, obtain the dominant structure surface group IV of the wellbore surrounding rock at different depths.

[0072] Specifically, the on-site geological survey adopts the line survey method, uses the geological compass and the measuring ruler to measure the occurrence of the shaft surrounding rock structure surface revealed by the shaft excavation, and records the occurrence data of the structure surface, including the strike, dip, inclination, structure surface density, width, filling and other information; then the collected shaft surrounding rock structure surface occurrence data is imported into the Dips software for statistical analysis, and the generated structure surface isodensity map and structure surface rose diagram (such as Figure 3 and Figure 4 As shown, Figure 3The dominant structural surface group IV of the surrounding rock at different depths is obtained. The spatial distribution pattern of the main controlling structural surface is clarified, providing a basis for the stability evaluation and support design of ultra-deep vertical shafts.

[0073] Step S22: Collect rock samples at different depths of the ultra-deep shaft, conduct rock mechanics tests, and obtain rock physical and mechanical parameters.

[0074] Specifically: Rock samples were taken at different excavation depths in the ultra-deep shaft and processed into standard rock samples in accordance with the ISRM "Standard for Rock Mechanics Test Methods". The physical parameters of the standard rock samples were measured and the average density was calculated to be 2.6g / cm 3 Among them, physical parameters include diameter, height, and mass.

[0075] Subsequently, uniaxial compressive strength tests, Brazilian splitting tests, and shear tests were carried out on standard rock samples to obtain rock physical and mechanical parameters. In this embodiment, the RQD value of the ultra-deep vertical shaft surrounding rock is generally above 70%; the angles of the joints and fissures in the wellbore surrounding rock are all high-inclination micro-cracks, with an inclination range of 60°~90° and an opening of 0.1mm. The results of the rock physical and mechanical tests show that the uniaxial compressive strength σ of the deep rock mass is c It reaches 150 MPa, the elastic modulus E is 47.61 MPa, the cohesion c is 18.95 MPa, and the internal friction angle φ is 35.71°.

[0076] Step S23: classify the rock mass quality grades of the surrounding rocks at different depths of the wellbore, and calculate the mechanical parameters of the wellbore rock mass in combination with the Hoek-Brown strength criterion.

[0077] Based on the engineering geological information of the surrounding rock of the ultra-deep vertical shaft and the results of rock physics and mechanics tests, the Barton rock mass quality index Q classification, rock mass geomechanics RMR classification and geological strength index GSI classification methods are used to classify the rock mass quality grades at different shaft depths. Specifically:

[0078] The Barton rock mass quality index Q classification method is used to classify the rock mass quality at different depths of the wellbore. The Q value is determined by the following formula:

[0079]

[0080] Where, RQD is the rock mass quality index; J n is the number of joint groups; J r is a joint rough system; J a is the joint alteration coefficient; J w is the joint water reduction factor; SRF is the stress reduction factor.

[0081] The rock mass geomechanics RMR classification method is used to classify the rock mass quality at different depths of the wellbore. The RMR classification consists of six index parameters: rock strength A1, RQD value A2, joint spacing A3, joint condition A4, groundwater A5, and correction coefficient A6 for the influence of joint direction on engineering. The RMR value is determined by the following formula:

[0082] RMR=A1+A2+A3+A4+A5+A6

[0083] The geological strength index (GSI) classification method is used to classify the rock mass quality at different depths in the wellbore. The geological strength index (GSI) classification method breaks through the limitations of RMR and Q methods, which cannot be well applied to broken rock masses with extremely poor rock quality. It reflects the degree of weakening of rock mass strength under various geological conditions and is used to describe the characteristics of rock mass. Its value ranges from 0 to 100.

[0084] In this embodiment, the geological strength index GSI classification is obtained from Table 1.

[0085] Table 1 is the GSI grading chart

[0086]

[0087] Based on the above three different types of rock mass quality classification methods, the rock mass quality grades of the surrounding rock masses at different depths of the ultra-deep vertical shaft are obtained, as shown in Table 2:

[0088] Table 2 Results of rock mass quality classification of surrounding rock masses at different depths of ultra-deep vertical shafts

[0089]

[0090] Based on the rock mass quality classification results of the surrounding rock mass at different depth levels of the ultra-deep vertical shaft, the mechanical parameters of the shaft rock mass are calculated in combination with the Hoek-Brown strength criterion.

[0091] Step S24: establishing an ultra-deep vertical shaft engineering property model based on the information of the dominant structural surface group IV of the wellbore surrounding rock, the rock physical and mechanical parameters, and the wellbore rock mass mechanical parameters.

[0092] Specifically, the three-dimensional cylindrical model of the wellbore is imported into the numerical simulation software, and the dominant structural surface group model of the wellbore surrounding rock is constructed to fit the three-dimensional cylindrical model of the wellbore. The rock physical and mechanical parameters and the wellbore rock mass mechanical parameters are set to establish the ultra-deep vertical shaft engineering property model to reflect the rock mass property information of the ultra-deep vertical shaft engineering, such as Figure 5 shown.

[0093] Step S3: obtaining the dynamic response characteristics and local stability evaluation parameters of the ultra-deep vertical shaft surrounding rock; and establishing a numerical model of the ultra-deep vertical shaft based on the dynamic response characteristics and local stability evaluation parameters.

[0094] Among them, the dynamic response characteristics include the distribution characteristics of the disturbance stress field caused by ultra-deep vertical shaft excavation, the shaft displacement information, and the range of the shaft plastic zone; the local stability evaluation parameters include the position of the wedge and the safety factor.

[0095] Step S31: Establish a two-dimensional plane model of the shaft section, input the physical and mechanical parameters of the rock mass and the ground stress field, and analyze the distribution characteristics of the disturbance stress field caused by ultra-deep shaft excavation, the shaft displacement information, and the range of the shaft plastic zone.

[0096] Specifically: Based on Rockscience2 geotechnical engineering numerical analysis software, a two-dimensional plane model of the ultra-deep vertical shaft section was established. The rock mass mechanical parameters were set according to the rock physical and mechanical parameters obtained in step 22, and the Hoek-Brown strength criterion was used to characterize the nonlinear mechanical behavior of the deep rock mass. Subsequently, the ground stress field was applied and the model grid was refined to ensure the calculation accuracy. During the simulation process, the shaft was excavated section by section according to the construction sequence, and iterative calculations were performed at each step until the convergence criteria were met and the calculation was completed. The distribution law of the stress concentration area around the shaft was revealed through the analysis of the principal stress trajectory, and the distribution characteristics of the disturbance stress field were determined; the wellbore convergence deformation characteristics were analyzed through the displacement vector field to determine the wellbore displacement information; the range of the wellbore plastic zone was determined by the Hoek-Brown strength criterion, thereby evaluating the potential damage risk and guiding the support design.

[0097] Step S32: Establish a three-dimensional geometric model of the wellbore section, input the information of the dominant structural surface group IV of the wellbore surrounding rock to generate a wedge distribution model of the wellbore surrounding rock, and obtain the wedge position and safety factor of the wellbore surrounding rock.

[0098] Specifically: Using Unwedge software, a 3D geometric model of a circular wellbore section was established based on the wellbore's design dimensions. Information such as the occurrence, spacing, and continuity parameters of Group IV of the dominant structural surfaces was input, and the mechanical parameters of Group IV, including the internal friction angle, cohesion, and tensile strength, were set. By calculating the spatial intersection and combination relationships of the dominant structural surfaces, a wedge distribution model for the wellbore's surrounding rock was automatically generated, identifying and positioning potentially dangerous wedges. Finally, the safety factor of each wedge was calculated using the principle of mechanical equilibrium, clarifying the spatial position and instability risk level of the wedge blocks, providing a basis for targeted support design.

[0099] Step S33: establishing a numerical model of the ultra-deep vertical shaft based on the distribution characteristics of the disturbance stress field during ultra-deep vertical shaft excavation, the shaft displacement information, the range of the shaft plastic zone, and the wedge position and safety factor of the shaft surrounding rock.

[0100] Specifically: import the wellbore three-dimensional cylindrical model, construct the disturbance stress field distribution characteristic model, the wellbore displacement model, the wellbore plastic zone model, and the wedge distribution model; fit the disturbance stress field distribution characteristic model, the wellbore displacement model, the wellbore plastic zone model, and the wedge distribution model with the wellbore three-dimensional cylindrical model to establish the ultra-deep vertical shaft numerical model, such as Figures 6 to 8 shown.

[0101] Step S4: establishing a comprehensive model of ultra-deep vertical shaft engineering disasters based on the ultra-deep vertical shaft geological model, the ultra-deep vertical shaft engineering property model, and the ultra-deep vertical shaft numerical model.

[0102] Based on the ultra-deep shaft geological model, ultra-deep shaft engineering property model and ultra-deep shaft numerical model, a comprehensive model of ultra-deep shaft engineering disasters is established by comprehensively considering geological conditions, engineering properties and numerical simulation results.

[0103] This application proposes a method for modeling engineering hazards in ultra-deep vertical shafts in metal mines. The method is applicable to ultra-deep vertical shafts with complex geological conditions exceeding 1,500 meters. It uses multi-dimensional model fusion to achieve early warning and prevention of hazards such as rockbursts and sudden water inrush. The method includes four core modules: The ultra-deep vertical shaft geological model utilizes engineering geological analysis, core logging, and 3D modeling techniques to construct a visualization model of the spatial distribution of geological anomalies such as fault fracture zones and aquifers, as well as rock formation characteristics. The ultra-deep vertical shaft engineering property model quantifies surrounding rock mechanical parameters and engineering response characteristics based on downhole structural surface occurrence surveys, wellbore rock mechanics tests, and rock physical and mechanical parameters. The ultra-deep vertical shaft numerical model relies on numerical simulation tools such as Rockscience2 and Unwedge to analyze the stress field evolution, displacement field distribution, plastic zone range, and surrounding rock wedge stability under the influence of wellbore excavation disturbances. The comprehensive engineering hazard model integrates geological conditions, engineering properties, and dynamic mechanical response data through the linkage of three models, breaking through the limitations of traditional single-factor analysis and revealing the multi-factor coupling mechanism of disasters. Realizing the integration of all-factor data of "geology-engineering-mechanics" can accurately predict the disaster risk threshold and provide a scientific basis for the optimization of support parameters and dynamic adjustment of construction plans.

[0104] It is easy for those skilled in the art to understand that, under the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed.

[0105] The above are merely preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application. The above are merely preferred embodiments of the present application. It should be noted that those skilled in the art may make various improvements and variations without departing from the technical principles of the present application, and such improvements and variations shall also be considered within the scope of protection of the present application.

Claims

1. A method for modeling disasters in ultra-deep shaft engineering of metal mines, characterized in that: include: Acquiring engineering geological information of the well construction area, and establishing an ultra-deep vertical shaft geological model based on the engineering geological information of the well construction area; Obtaining a dominant structural surface group of surrounding rocks at different depths of an ultra-deep vertical shaft, obtaining rock physical and mechanical parameters, and obtaining wellbore rock mass mechanical parameters; and establishing an ultra-deep vertical shaft engineering property model based on the dominant structural surface group, the rock physical and mechanical parameters, and the wellbore rock mass mechanical parameters; Obtaining dynamic response characteristics and local stability evaluation parameters of the ultra-deep vertical shaft surrounding rock; establishing an ultra-deep vertical shaft numerical model based on the dynamic response characteristics and the local stability evaluation parameters; Establishing a comprehensive model of ultra-deep vertical shaft engineering disasters based on the ultra-deep vertical shaft geological model, the ultra-deep vertical shaft engineering property model, and the ultra-deep vertical shaft numerical model; The acquisition of dynamic response characteristics of the ultra-deep vertical shaft surrounding rock and local stability evaluation parameters; The steps for establishing the ultra-deep shaft numerical model based on the dynamic response characteristics and local stability evaluation parameters include: Establish a two-dimensional plane model of the shaft section, input rock mass mechanical parameters and ground stress field, and analyze the distribution characteristics of the disturbance stress field, shaft displacement information, and the range of the shaft plastic zone caused by ultra-deep shaft excavation; Establish a three-dimensional geometric model of the wellbore section, input the information of the dominant structural surface group of the wellbore surrounding rock to generate a wedge distribution model of the wellbore surrounding rock, and obtain the wedge position and safety factor of the wellbore surrounding rock; Based on the distribution characteristic information of the disturbance stress field during the excavation of the ultra-deep vertical shaft, the shaft displacement information, the range information of the shaft plastic zone, and the wedge position and safety factor of the shaft surrounding rock, a numerical model of the ultra-deep vertical shaft is established.

2. A method for modeling ultra-deep shaft engineering disasters in metal mines according to claim 1, characterized in that: The step of obtaining engineering geological information of the well construction area and establishing a geological model of the ultra-deep vertical shaft based on the engineering geological information of the well construction area includes: Conduct engineering geological surveys on the ultra-deep vertical shaft construction area to obtain engineering geological information of the well construction area; Based on the engineering geological information of the well construction area, the spatial location of the fault fracture zone and the aquifer is divided, and the spatial interaction relationship between the geological anomaly and the ultra-deep vertical shaft is determined; Compile the rock core information of engineering survey holes and divide the ultra-deep vertical shaft engineering survey rock groups based on the rock core information of engineering survey holes; Based on the spatial interaction relationship between the geological anomaly and the ultra-deep vertical shaft and the rock formation of the ultra-deep vertical shaft engineering survey, a geological model of the ultra-deep vertical shaft is established.

3. A method for modeling ultra-deep shaft engineering disasters in metal mines according to claim 2, characterized in that: The aquifer includes a top drainage section, a mining-affected section, and a deep unaffected section.

4. A method for modeling ultra-deep shaft engineering disasters in metal mines according to claim 2, characterized in that: The core information of the engineering exploration holes is cataloged, wherein the core information of the exploration holes includes color, weathering degree, rock structure, structural plane spacing, hardness, rock lithology and occurrence depth.

5. The method for modeling ultra-deep shaft engineering disasters in metal mines according to claim 2, characterized in that: Before the step of establishing a comprehensive model of ultra-deep vertical shaft engineering disasters based on the spatial interaction relationship between the geological anomaly and the ultra-deep vertical shaft and the ultra-deep vertical shaft engineering survey rock formation, the method further includes: The deep stratum core information of the excavation working face is cataloged, and the engineering survey hole core information is corrected based on the deep stratum core information of the excavation working face.

6. The method for modeling ultra-deep shaft engineering disasters in metal mines according to claim 1, characterized in that: Obtain the dominant structural surface groups of the surrounding rocks at different depths of ultra-deep vertical shafts, obtain the rock physical and mechanical parameters, and obtain the mechanical parameters of the wellbore rock mass; The step of establishing an ultra-deep vertical shaft engineering property model based on the dominant structural surface group, the rock physical and mechanical parameters, and the rock mass mechanical parameters includes: Conduct an underground field survey of the entire ultra-deep shaft excavation process to obtain information on the occurrence of the surrounding rock structure surfaces at different depths of the ultra-deep shaft. Based on this information, obtain information on the dominant structural surface groups of the surrounding rock at different depths. Collect rock samples at different depths in ultra-deep shafts, conduct rock mechanics tests, and obtain rock physical and mechanical parameters; Classify the rock mass quality levels of surrounding rocks at different depths of the wellbore and calculate the mechanical parameters of the wellbore rock mass using the Hoek-Brown strength criterion; An ultra-deep vertical shaft engineering property model is established based on the information of the dominant structural surface group of the wellbore surrounding rock, the rock physical and mechanical parameters, and the wellbore rock mass mechanical parameters.

7. A method for modeling ultra-deep shaft engineering disasters in metal mines according to claim 6, characterized in that: The rock mechanics tests include uniaxial compressive strength test, Brazilian split test and shear test.

8. A method for modeling ultra-deep shaft engineering disasters in metal mines according to claim 6, characterized in that: The method for classifying the rock mass quality grades of surrounding rocks at different depths of the wellbore includes adopting the Barton rock mass quality index Q classification method, the rock mass geomechanics RMR classification method and the geological strength index GSI classification method.

9. The method for modeling ultra-deep shaft engineering disasters in metal mines according to claim 1, characterized in that: The information of the dominant structural surface group of the wellbore surrounding rock includes the geometric and mechanical characteristic parameters of the dominant structural surface group and the strength parameters of the dominant structural surface group; Among them, the geometric and mechanical characteristic parameters of the advantageous structural surface group include structural surface occurrence, structural surface spacing and continuity parameters; the strength parameters of the advantageous structural surface group include internal friction angle, cohesion and tensile strength.

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