A method for optimizing the configuration of a machine-rock coupled drill bit in a drill-and-blast tunnel

Abstract

The application provides a drill-and-blast tunnel machine-rock coupled drill bit configuration optimization design method, and belongs to the field of tunnel and underground engineering mechanized drilling technology, and the method comprises the following steps: S1, determining the variable design parameters of the rock drill rig drill bit; S2, setting multiple groups of drill bit configuration comparison working conditions; S3, constructing a refined finite element coupling model; S4, extracting indexes; S5, calculating quantitative evaluation indexes; S6, determining the rock breaking topology mode; S7, constructing a comprehensive evaluation model; S8, sorting the optimal drill bit configuration parameter combination. The application identifies the rock breaking topology mode based on the actual rock breaking damage characteristics, constructs a dynamic weight evaluation system suitable for different rock breaking mechanisms, and incorporates the engineering construction feasibility constraint, realizes the accurate optimization of the drill bit configuration suitable for specific surrounding rock conditions, and thus improves the drilling efficiency of the rock drill rig, reduces the construction cost, and guarantees the safety and engineering quality of the drill-and-blast tunnel construction.

Description

Technical Field

[0001] This invention relates to the field of mechanized drilling technology for tunnels and underground engineering, and in particular to an optimized design method for the configuration of a drill bit coupled with rock in a drill-and-blast tunnel. Background Technology

[0002] With the continuous expansion of tunnel construction scale and the increasing complexity of construction, the drill-and-blast method, as the mainstream method for tunnel construction, has placed increasingly stringent requirements on drilling accuracy, drilling efficiency, and control of surrounding rock disturbance. The drilling rig is the core equipment for achieving mechanized and efficient tunnel drilling; the dynamic interaction mechanism between its drill bit and the surrounding rock directly determines the safety, efficiency, and quality of the drilling operation.

[0003] Currently, conical and spherical drill bits are widely used in drilling operations in engineering practice. However, systematic research on the intrinsic correlation between drill bit configuration parameters and rock-breaking performance is still lacking. Existing drill bit selection and design largely rely on engineering experience and field trial and error, making it difficult to accurately match the optimal combination of drill bit configuration parameters according to the geological characteristics of different surrounding rocks, thus failing to fully utilize the operational efficiency of rock drilling rigs. Furthermore, existing research often focuses on the impact of single factors on rock-breaking effects, failing to comprehensively reveal the drill bit-surrounding rock interaction mechanism under multi-parameter coupling. Rock-breaking mode determination is often based on theoretical assumptions rather than actual rock-breaking characteristics, and the fixed weights used in the evaluation system cannot adapt to the performance requirements of different rock-breaking mechanisms. Moreover, the impact of construction process feasibility on the actual application effect of drill bits is generally ignored, severely restricting further improvements in drilling efficiency of rock drilling rigs and the level of intelligent tunnel construction. Therefore, there is an urgent need to establish a rock drilling rig drill bit optimization design method that balances the accuracy of rock-breaking mechanisms, the scientific nature of the evaluation system, and engineering practicality. Summary of the Invention

[0004] This invention provides a method for optimizing the configuration of drill bits used in drill-and-blast tunneling. It employs a technical approach combining refined numerical simulation with multi-dimensional dynamic comprehensive evaluation. Based on actual rock-breaking damage characteristics, it identifies rock-breaking topology patterns, constructs a dynamic weighted evaluation system adaptable to different rock-breaking mechanisms, and incorporates engineering feasibility constraints. This achieves precise optimization of drill bit configurations to suit specific surrounding rock conditions, thereby improving the drilling efficiency of the drilling rig, reducing construction costs, and ensuring the safety and quality of drill-and-blast tunnel construction.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A method for optimizing the configuration of a drill bit coupled with rock in a drill-and-blast tunnel boring machine includes: S1: Determine the variable design parameters of the drill bit on the rock drilling rig; S2: Based on the aforementioned variable design parameters, the system sets up multiple sets of drill tooth configuration comparison conditions using a full factorial design method combined with orthogonal array reduction technology. S3: For each set of drill bit configuration comparison working conditions, establish a three-dimensional geometric model of the drill bit, and construct a refined finite element coupled model that includes the drill bit and the core drilling area of ​​the surrounding rock. S4: Extract and analyze the surrounding rock mechanical response index, key drilling parameters, and drill bit response index under each working condition from the numerical simulation results of the refined finite element coupled model. S5: Based on the extracted surrounding rock mechanical response index, drilling key parameters and drill bit response index, calculate and analyze the quantitative evaluation index under each working condition; S6: Analyze the cloud map damage area of ​​the numerical simulation results, extract and calculate the connected domain shape features of the damage area, and determine the point-line-surface rock breaking topology pattern corresponding to each working condition based on the actual rock breaking damage morphology. S7: Using the calculated quantitative evaluation indicators and the determined rock-breaking topology as inputs, and combining engineering experience, construct a comprehensive evaluation model that dynamically adjusts the weights of the quantitative evaluation indicators based on the rock-breaking topology. S8: The comprehensive evaluation model is used to make a preliminary score for each working condition. The preliminary score is corrected by introducing a penalty factor in combination with the two engineering feasibility factors of chip removal smoothness and anti-clogging performance. The score is sorted according to the corrected comprehensive score, and the optimal combination of drill tooth configuration parameters that takes into account rock breaking performance and engineering practicality under the target surrounding rock conditions is output.

[0006] In this specification, in S1, the variable design parameters include the drill bit shape, the number of external teeth, the number of internal teeth, the tooth diameter, and the spatial layout of the internal and external teeth. The drill bit shape is selected as spherical or conical teeth according to the characteristics of the target surrounding rock. Each parameter is taken at three to five levels based on engineering experience. The layout of the internal and external teeth includes the internal teeth being evenly distributed at the center and the external teeth being evenly distributed around the circumference.

[0007] In this specification, S2 comprehensively considers the interaction of all factors, including drill tooth shape, number of external teeth, number of internal teeth, tooth diameter, and spatial layout of internal and external teeth, to design the working conditions of the drill tooth configuration. Orthogonal arrays are used to reduce the working conditions generated by the full factorial design, thereby reducing the amount of calculation while ensuring that each factor and the interaction between factors can be fully analyzed.

[0008] In this specification, in S3, all model components in the refined finite element coupled model are simulated using solid elements, and local mesh refinement is implemented in the core drilling area of ​​the refined finite element coupled model to improve the accuracy of stress calculation; all external boundaries of the refined finite element coupled model are subject to fixed constraints, the drill bit in the refined finite element coupled model is defined as a rigid body, and drilling pressure and rotation speed consistent with actual construction are applied to reproduce the real dynamic drilling loading conditions.

[0009] In this specification, in S4, the surrounding rock mechanical response indicators include plastic strain, stress, and shear failure; the key drilling parameters include drilling acceleration, drilling displacement, and drilling speed; and the drill bit response indicators include reaction force and reaction torque. The above three types of indicators together characterize the dynamic interaction process between the drill bit and the surrounding rock.

[0010] In this specification, S5, the quantitative evaluation indicators include the volume ratio of surrounding rock damage, the average drilling torque, and the average specific energy; wherein the volume ratio of surrounding rock damage is obtained by post-processing and statistical analysis of the numerical simulation results, and the average drilling torque is the arithmetic mean calculated from the drilling torque time history curve of the drill bit in the steady-state drilling stage, wherein the steady-state drilling stage is the period in the torque time history curve where the fluctuation amplitude is less than 10% of the average value.

[0011] In this specification, the rules for determining the point-line-surface rock breaking topology in S6 are as follows: when the connected domains of the damaged area exhibit a circular independent distribution feature, it is determined to be a point-shaped rock breaking mode; when the connected domains of the damaged area exhibit a continuous linear distribution feature, it is determined to be a linear rock breaking mode; when the connected domains of the damaged area exhibit a cross-network distribution feature, it is determined to be a surface-shaped rock breaking mode.

[0012] In this specification, in S7, the comprehensive evaluation model adopts a weighted scoring method. Based on the differences in sensitivity of different rock breaking topology modes to each quantitative evaluation index, the corresponding weight adjustment coefficients are determined in advance through engineering experience. When a certain working condition is determined to be a specific rock breaking topology mode, the weight of the corresponding quantitative evaluation index in the weighted scoring function is automatically multiplied by the corresponding adjustment coefficient.

[0013] In this manual, under section S8, for the working condition of planar rock breaking mode, due to the dense layout of the drill teeth, it is easy to cause narrow cuttings removal channels and difficulty in removing rock cuttings. Therefore, corresponding scoring penalty factors are set according to the level of cuttings removal difficulty and anti-clogging performance to deduct from the preliminary comprehensive score of this working condition.

[0014] In this manual, the optimal combination of drill tooth configuration parameters output in S8 includes the drill tooth shape, number of external teeth, number of internal teeth, tooth diameter, and spatial layout of internal and external teeth. It also includes the expected specific energy range and average torque range corresponding to this parameter combination, providing a direct basis for on-site drill bit manufacturing and construction parameter adjustment.

[0015] In summary, the present invention has at least the following beneficial effects: This invention effectively overcomes the shortcomings of existing technologies, such as drill bit design relying on experience and trial and error, rock breaking mode judgment being divorced from reality, rigid evaluation systems, and neglecting engineering feasibility. It achieves scientific, precise, and practical optimization design of drill bit configurations for rock drilling rigs. By constructing a refined machine-rock coupled dynamic model, it can accurately reproduce the entire process of dynamic interaction between the drill bit and the surrounding rock, and comprehensively reveal the rock breaking mechanism under different drill bit configurations.

[0016] This invention innovatively proposes a rock-breaking topology pattern recognition method based on the connected domain characteristics of the damage zone in numerical simulation. Starting from actual rock-breaking results, it establishes an intrinsic relationship between drill bit configuration and rock-breaking performance, significantly improving the accuracy and reliability of rock-breaking pattern determination. The comprehensive evaluation method, which dynamically adjusts the weights of quantitative indicators based on topology patterns, can adapt to the performance-sensitive characteristics under different rock-breaking mechanisms, making the evaluation results more aligned with actual engineering needs.

[0017] This invention is the first to incorporate engineering feasibility into the drill bit optimization evaluation system. By introducing a construction process penalty factor, it effectively balances theoretical rock-breaking performance with on-site construction requirements, avoiding the drawbacks of theoretically optimal configurations being impractical due to problems such as poor chip removal and easy clogging. This invention significantly shortens the drill bit development cycle, reduces on-site testing costs and construction risks, significantly improves the drilling efficiency and operational stability of rock drilling rigs, ensures the reliability and economy of drill-and-blast tunnel construction, and provides important technical support for intelligent tunnel engineering construction. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the drill bit configuration optimization design method for the drill-blast tunnel boring machine-rock coupling method involved in this invention.

[0020] Figure 2 This is a schematic diagram illustrating the process of establishing a numerical simulation of drill bit-surrounding rock coupling involved in this invention.

[0021] Figure 3 This is a schematic diagram of the finite element numerical simulation involved in this invention.

[0022] Figure 4 This is a schematic diagram of the drilling process simulated in the present invention.

[0023] Figure 5 This is a schematic diagram of the numerical simulation cloud map under some of the working conditions involved in this invention.

[0024] Figure 6 This is a schematic diagram of the reaction force time history curve involved in this invention. Figure 7 This is a schematic diagram of the anti-torque time history curve involved in this invention. Detailed Implementation

[0025] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of the embodiments of the invention. Therefore, the drawings and description are considered to be exemplary in nature and not restrictive.

[0026] The following disclosure provides many different implementations or examples for carrying out different structures of the embodiments of the present invention. To simplify the disclosure of the embodiments of the present invention, specific examples of components and arrangements are described below. Of course, these are merely examples and are not intended to limit the embodiments of the present invention. Furthermore, reference numerals and / or reference letters may be repeated in different examples of the embodiments of the present invention; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various implementations and / or arrangements discussed.

[0027] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0028] like Figure 1 As shown, this embodiment provides a method for optimizing the configuration design of a drill bit coupled with a rock in a drill-and-blast method, including: S1: Determine the variable design parameters of the drill bit on the rock drilling rig; S2: Based on the aforementioned variable design parameters, the system sets up multiple sets of drill tooth configuration comparison conditions using a full factorial design method combined with orthogonal array reduction technology. S3: For each set of drill bit configuration comparison working conditions, establish a three-dimensional geometric model of the drill bit, and construct a refined finite element coupled model that includes the drill bit and the core drilling area of ​​the surrounding rock. S4: Extract and analyze the surrounding rock mechanical response index, key drilling parameters, and drill bit response index under each working condition from the numerical simulation results of the refined finite element coupled model. S5: Based on the extracted surrounding rock mechanical response index, drilling key parameters and drill bit response index, calculate and analyze the quantitative evaluation index under each working condition; S6: Analyze the cloud map damage area of ​​the numerical simulation results, extract and calculate the connected domain shape features of the damage area, and determine the point-line-surface rock breaking topology pattern corresponding to each working condition based on the actual rock breaking damage morphology. S7: Using the calculated quantitative evaluation indicators and the determined rock-breaking topology as inputs, and combining engineering experience, construct a comprehensive evaluation model that dynamically adjusts the weights of the quantitative evaluation indicators based on the rock-breaking topology. S8: The comprehensive evaluation model is used to make a preliminary score for each working condition. The preliminary score is corrected by introducing a penalty factor in combination with the two engineering feasibility factors of chip removal smoothness and anti-clogging performance. The score is sorted according to the corrected comprehensive score, and the optimal combination of drill tooth configuration parameters that takes into account rock breaking performance and engineering practicality under the target surrounding rock conditions is output.

[0029] In some embodiments, in S1, the variable design parameters include the drill tooth shape, the number of external teeth, the number of internal teeth, the tooth diameter, and the spatial layout of the internal and external teeth; wherein the drill tooth shape is selected as spherical teeth or conical teeth according to the characteristics of the target surrounding rock, and each parameter is taken at three to five levels based on engineering experience, and the internal and external tooth layout includes the internal teeth being evenly distributed at the center and the external teeth being evenly distributed around the circumference.

[0030] In some embodiments, in S2, the working condition design of the drill tooth configuration is carried out by comprehensively considering the interaction of all factors such as drill tooth shape, number of external teeth, number of internal teeth, tooth diameter, and spatial layout of internal and external teeth; the working condition generated by the full factorial design is reduced by using an orthogonal array, thereby reducing the amount of calculation while ensuring that each factor and the interaction between factors can be fully analyzed.

[0031] In some embodiments, in S3, all model components in the refined finite element coupling model are simulated using solid elements, and local mesh refinement is performed on the core drilling area in the refined finite element coupling model to improve the accuracy of stress calculation; all external boundaries of the refined finite element coupling model are subject to fixed constraints, the drill bit in the refined finite element coupling model is defined as a rigid body, and drilling pressure and rotation speed consistent with actual construction are applied to reproduce the real dynamic drilling loading conditions.

[0032] In some embodiments, in S4, the surrounding rock mechanical response indicators include plastic strain, stress, and shear failure; the key drilling parameters include drilling acceleration, drilling displacement, and drilling speed; the drill bit response indicators include reaction force and reaction torque; the above three types of indicators together characterize the dynamic interaction process between the drill bit and the surrounding rock.

[0033] In some embodiments, in S5, the quantitative evaluation indicators include the proportion of surrounding rock damage volume, the average drilling torque, and the average specific energy; wherein the proportion of surrounding rock damage volume is obtained by post-processing and statistically analyzing the numerical simulation results, specifically: defining the area where the equivalent plastic strain of the surrounding rock unit is greater than or equal to 0.01 as the damage zone, and calculating the ratio of the total volume of the damage zone to the total volume of the core drilling area of ​​the surrounding rock; the average drilling torque is the arithmetic mean calculated from the drilling torque time history curve of the drill bit in the steady-state drilling stage, wherein the steady-state drilling stage is the period in the torque time history curve where the fluctuation amplitude is less than 10% of the average value.

[0034] In some embodiments, in S6, the determination rule for the point-line-surface rock breaking topology is as follows: when the connected domain of the damaged area exhibits a circular independent distribution feature, it is determined to be a point-shaped rock breaking mode; when the connected domain of the damaged area exhibits a continuous linear distribution feature, it is determined to be a linear rock breaking mode; when the connected domain of the damaged area exhibits a cross-network distribution feature, it is determined to be a surface-shaped rock breaking mode.

[0035] In some embodiments, in S7, the comprehensive evaluation model adopts a weighted scoring method. Based on the differences in sensitivity of different rock breaking topology modes to each quantitative evaluation index, the corresponding weight adjustment coefficients are determined in advance through engineering experience. When a certain working condition is determined to be a specific rock breaking topology mode, the weight of the corresponding quantitative evaluation index in the weighted scoring function is automatically multiplied by the corresponding adjustment coefficient.

[0036] In some embodiments, in S8, for the working condition of the planar rock breaking mode, since its dense drill bit layout easily leads to narrow cuttings removal channels and difficulty in removing rock cuttings, a corresponding scoring penalty factor is set according to its cuttings removal difficulty level and anti-clogging performance level to deduct the preliminary comprehensive score of the working condition.

[0037] In some embodiments, in S8, the output optimal drill tooth configuration parameter combination includes drill tooth shape, number of external teeth, number of internal teeth, tooth diameter, and spatial layout of internal and external teeth, along with the expected specific energy range and average torque range corresponding to the parameter combination, providing a direct basis for on-site drill bit manufacturing and construction parameter adjustment.

[0038] The technical concept of this invention is as follows: This invention first determines the core variable design parameters of the drill bit of the rock drilling rig, and uses a full factorial design method combined with orthogonal array reduction technology to systematically generate comparative working conditions of drill tooth configuration covering all combinations of key parameters. For each working condition, a refined three-dimensional geometric model of the drill bit is established, and a finite element coupled model containing the core drilling area of ​​the drill bit and the surrounding rock is constructed. Boundary conditions and dynamic loads consistent with actual construction are applied to simulate the real drilling process.

[0039] Multi-dimensional indicators such as surrounding rock mechanical response, drilling process parameters, and drill bit dynamic response are extracted from the numerical simulation results. Three core quantitative evaluation indicators, namely the proportion of surrounding rock damage volume, average drilling torque, and average specific energy, are calculated. By analyzing the damage area in the numerical simulation cloud map, the shape characteristics of the connected domain of the damage area are calculated, and the "point-line-surface" rock breaking topology mode corresponding to each working condition is determined.

[0040] Using quantitative evaluation indicators and rock-breaking topology patterns as inputs, a multi-indicator weighted comprehensive evaluation model is constructed based on the dynamic adjustment of the weights of quantitative indicators according to the topology patterns. In the comprehensive scoring and ranking stage, engineering feasibility factors such as chip removal smoothness and anti-clogging performance are introduced to apply corresponding scoring penalties to rock-breaking patterns that are prone to construction problems. Finally, the optimal combination of drill bit configuration parameters that takes into account both rock-breaking performance and engineering practicality under the target surrounding rock conditions is output, providing a direct basis for on-site drill bit design and construction parameter adjustment.

[0041] Traditional drill bit design often relies on empirical formulas or single-factor comparative experiments. This approach struggles to comprehensively capture the impact of multi-parameter coupling on rock-breaking efficiency, and is also time-consuming and costly. This invention, however, first determines the range of selectable drill bit shapes based on geological parameters such as the type of target surrounding rock, uniaxial compressive strength, and joint development (spherical teeth are suitable for hard and brittle surrounding rocks, while conical teeth are suitable for medium-hard surrounding rocks). Based on this, parameters such as the number of external teeth, the number of internal teeth, tooth diameter, and the layout of internal and external teeth are set as variable design factors. Each factor is divided into 3-5 levels based on practical engineering experience, and a full-factor design method is used to generate all possible drill bit configuration conditions.

[0042] For each drill bit configuration, a refined geometric model including the drill bit matrix and drill bits was created using modeling software and then imported into a finite element analysis platform. When constructing the finite element coupled model, the surrounding rock was defined as a Drucker-Prager constitutive model. Binding constraints were set to simulate the contact between the drill bit and the surrounding rock. The mesh was locally refined in the core drilling area, and boundary conditions consistent with the actual working parameters of the drilling rig were applied, such as a drill bit rotation speed of 60–120 r / min and a thrust of 10–30 kN.

[0043] The numerical simulation results extract surrounding rock response indices such as stress, plastic strain, and shear damage; key drilling parameters such as drilling displacement, drilling speed, and drilling acceleration; and drill bit response indices such as the time history curves of the drill bit's reaction force and reaction torque. Through post-processing, the system statistically analyzes the proportion of surrounding rock damage volume; it extracts steady-state drilling periods from the torque time history curve where the fluctuation amplitude is less than 10% of the average value, calculates the average torque during these periods, and calculates the average specific energy using the formula: ; in Indicates average specific energy. For drilling pressure, For rotational speed, The average torque. This represents the load-bearing area of ​​the drill bit (the cross-sectional area of ​​the drill bit). This represents the drilling speed. Simultaneously, image analysis is performed on the damaged area in the simulation result cloud map to calculate the number and shape features of connected components within the damaged area, identifying its "point-line-surface" rock-breaking topology. Specifically, the damaged area cloud map is extracted using ABAQUS post-processing; the number of connected components in the damaged area is calculated using an 8-neighborhood connectivity recognition algorithm, and shape feature parameters such as aspect ratio and area percentage are quantified to accurately determine the "point-line-surface" rock-breaking topology. A multi-index weighted comprehensive evaluation model is constructed by using three quantitative indicators—surrounding rock damage volume, average torque, and average specific energy—along with the topological pattern as input. The weights are determined using the entropy weight method combined with engineering experience: the entropy value of each indicator is calculated to obtain the objective weight. Furthermore, different rock-breaking topological patterns exhibit varying sensitivities to the quantitative indicators, and the weights of the weighted scoring function are dynamically adjusted to ultimately achieve a comprehensive score.

[0044] When comprehensively scoring and ranking working conditions, construction process factors such as chip removal smoothness and anti-clogging performance are considered. For working conditions with a planar rock breaking topology, corresponding scoring penalties are applied. The highest-scoring drill bit configuration parameter combination is output, including drill bit shape, number of external teeth, number of internal teeth, tooth diameter, and spatial layout of the drill bits. The expected specific energy range and average torque range of this combination are also provided for use in on-site drill bit design and construction parameter adjustments.

[0045] In some embodiments, in step S2, multiple working conditions are set. Based on the variables defined in step S1, and according to the surrounding rock conditions, a certain range of parameter values ​​are selected. Using a full-factor design method, multiple sets of drill bit configuration comparison working conditions are systematically set. Typical working conditions include: B-L6S3 (spherical teeth, 6mm outer diameter, 3mm inner diameter), B-L6S2 (spherical teeth, 6mm outer diameter, 2mm inner diameter), B-L3S3 (spherical teeth, 3mm outer diameter, 3mm inner diameter), B-D9~B-D11 (different tooth diameters, 6mm outer diameter, 3mm inner diameter), and C-L6S3 (conical teeth, 6mm outer diameter, 3mm inner diameter), etc. To avoid an excessive number of design working conditions, the full-factor design method uses orthogonal arrays to reduce the number of working conditions while ensuring that the interactions between factors can be analyzed.

[0046] In some embodiments, in S3, a numerical model is established with dimensions of 300mm*200mm*300mm (length*width*height), wherein the diameter of the core drilling area is 90mm. (Reference) Figure 2 The specific steps are as follows: S301: Based on the surveyed variable design parameters of the drill bit, construct a refined geometric model of the drill bit, including tooth surface distribution and tooth profile. S302: Assign corresponding parameters to the numerical simulation based on the geological conditions of the target surrounding rock, construct the surrounding rock model, and delineate the key borehole areas; S303: Apply fixed constraints to the external boundary of the constructed numerical simulation, and implement local mesh refinement for the core drilling area to ensure the accuracy of the numerical simulation; S304: Collaborate and refine the drill bit geometry model and the surrounding rock model to construct a three-dimensional numerical model of drill bit-surrounding rock coupling; S305: Based on the analysis of the dynamic parameters of the drill bit of the rock drilling rig, the corresponding dynamic parameters are assigned to the drill bit in the coupled model; S306: Outputs numerical simulation results of drill bit-surrounding rock coupling under different working conditions, including the mechanical response indices of the surrounding rock, drilling parameters, and drill bit response indices. The completed finite element numerical model itself is referenced. Figure 3 The model's dynamic drilling process reference Figure 4 This represents the changes in the surrounding rock response during the drilling process: Figure 4 (1) in the figure represents the change in the surrounding rock response when the drill bit contacts the surrounding rock. Figure 4 (2) in the figure represents the change in the surrounding rock response during continuous drilling. Figure 4 (3) in the figure represents the change in the surrounding rock response formed by the borehole.

[0047] In some embodiments, S4 involves analyzing the response indices and key parameters obtained from numerical simulation, specifically analyzing shear failure, plastic strain zone, and stress contour plot, and analyzing the time history curves of reaction force and reaction torque (e.g., Figure 6 and Figure 7 ), and analyze drilling speed, drilling displacement and drilling acceleration.

[0048] In some embodiments, in S5, quantitative indicators are calculated. Based on the analysis results in S4 and the post-processed data, the system statistically analyzes the proportion of surrounding rock damage volume and the average torque for each working condition; and calculates the average specific energy for each working condition using the average specific energy calculation formula.

[0049] In some embodiments, in S6, the numerical simulation cloud map of the working conditions after reduction by orthogonal experiment (e.g.) is used. Figure 5 ), analyze and calculate the shape characteristics of the connected domains in the damaged area, and determine the corresponding rock-breaking topology.

[0050] In some embodiments, S7, quantitative indicators and topological patterns are used as inputs (ratio of surrounding rock damage volume). average specific energy average torque T Topology pattern quantization score M Based on engineering experience, a comprehensive evaluation model was constructed.

[0051] MThe topology pattern is quantized and set as: point pattern. M =1, linear mode M =3, Area mode M =5.

[0052] The weights of each indicator are determined using the entropy weight method. The steps are briefly described as follows: Construct the original data matrix, arranging the values ​​of m working conditions and n evaluation indicators into a matrix. Perform forward normalization and data forwarding, forward processing of inverse indicators, and then calculate the characteristic ratio p for each working condition under each indicator. ij ; Calculate the information entropy e of each indicator using the existing formula; calculate the difference coefficient of each indicator, the larger the difference coefficient, the richer the information; finally determine the objective weight, that is, the proportion of the difference coefficient of each indicator to the sum of the difference coefficients of all indicators.

[0053] A weighted scoring method is used for the overall score. The formula for the overall score is: ; Among them, the average specific energy weight Damage volume ratio weight Average torque weight These are objective weights determined by the entropy weight method. The superscript "~" indicates the index value after normalization, and M is the topological pattern quantization score.

[0054] Different rock-breaking topology modes exhibit varying degrees of sensitivity to quantitative indicators. For example, based on engineering experience, it has been found that the "point-like mode" is particularly sensitive to the "surrounding rock damage volume ratio," but not to fluctuations in the "average torque." Therefore, adjustments are made based on engineering experience: when the rock-breaking topology mode is point-like, the surrounding rock damage volume ratio is the most sensitive, so its weight is multiplied by a coefficient of 1.3, and the average specific energy weight is multiplied by a coefficient of 0.8; when it is linear, the average specific energy is the most sensitive to energy efficiency, so its weight is multiplied by a coefficient of 1.4; and when it is planar, the average torque is the most sensitive to chip removal resistance, so its weight is multiplied by a coefficient of 1.5.

[0055] The final weight is obtained by multiplying the objective weight by the corresponding adjustment coefficient, and the topology pattern quantization score weight. It is fixed at 0.1 and does not participate in dynamic adjustment.

[0056] In some embodiments, S8, considering the drilling chip removal smoothness construction process factors, a penalty factor P is set to correct the above comprehensive score, resulting in the final score. While the densely packed cutting tooth layout in the "planar" rock-breaking topology mode offers high rock-breaking efficiency, it also increases the risk of difficulties in chip removal and insufficient cooling, thereby reducing overall efficiency and service life. Therefore, appropriate scoring penalties are needed for different drill tooth operating conditions. ; Among them, the penalty factor P The value is determined based on the width of the drill tooth chip removal channel. Wc Ratio to tooth diameter Determined, when When the value is greater than 0.6, chip removal is smooth. P =0; when 0.3 < When the concentration is ≤0.6, chip removal is generally normal. P =0.1; when When the concentration is ≤0.3, chip removal is difficult. P =0.3. Wherein Wc and The calculation method is as follows: ; ; Where R is the circumference radius of the external teeth obtained from the three-dimensional geometric model established in S3, N is the number of external teeth, and D is the diameter of the drill teeth.

[0057] The system comprehensively scores and ranks each working condition, and outputs the optimal combination of drill bit configuration parameters that has excellent performance, feasible process, and good engineering adaptability under the target surrounding rock conditions.

[0058] The embodiments described above are for illustrative purposes only and are not intended to limit the invention. Therefore, any changes in numerical values ​​or substitutions of equivalent elements should still fall within the scope of this invention.

[0059] The above detailed description will enable those skilled in the art to understand that the present invention can indeed achieve the aforementioned objectives and has complied with the provisions of the Patent Law.

[0060] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the invention. The above descriptions are merely preferred embodiments of the invention and are not intended to limit the invention. It should be noted that any modifications, equivalent substitutions, and improvements made within the spirit and principles of the invention should be included within the scope of protection of the invention.

[0061] It should be noted that the above description of the process is for illustrative purposes only and does not limit the scope of this specification. Those skilled in the art can make various modifications and changes to the process under the guidance of this specification. However, these modifications and changes remain within the scope of this specification.

[0062] The basic concepts have been described above. Obviously, for those skilled in the art who have read this application, the above disclosure is merely illustrative and does not constitute a limitation of this application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements, and corrections to this application. Such modifications, improvements, and corrections are suggested in this application, and therefore, such modifications, improvements, and corrections still fall within the spirit and scope of the exemplary embodiments of this application.

[0063] Furthermore, this application uses specific terms to describe its embodiments. For example, "an embodiment," "one embodiment," and / or "some embodiments" refer to a particular feature, structure, or characteristic related to at least one embodiment of this application. Therefore, it should be emphasized and noted that "an embodiment," "one embodiment," or "an alternative embodiment" mentioned twice or more in different positions in this specification do not necessarily refer to the same embodiment. In addition, certain features, structures, or characteristics in one or more embodiments of this application can be appropriately combined.

[0064] Furthermore, those skilled in the art will understand that aspects of this application can be described and illustrated through several patentable types or situations, including any new and useful combination of processes, machines, products, or substances, or any new and useful improvements thereof. Therefore, aspects of this application can be implemented entirely in hardware, entirely in software (including firmware, resident software, microcode, etc.), or a combination of hardware and software. All of the above hardware or software can be referred to as a “unit,” “module,” or “system.” Furthermore, aspects of this application can take the form of a computer program product embodied in one or more computer-readable media, wherein computer-readable program code is contained therein.

[0065] The computer program code required for the operation of each part of this application can be written in any one or more programming languages, including object-oriented programming languages ​​such as Java, Scala, Smalltalk, Eiffel, JADE, Emerald, C++, C#, VB.NET, and Python; general programming languages ​​such as C; Visual Basic, Fortran2103, Perl, COBOL2102, PHP, and ABAP; dynamic programming languages ​​such as Python, Ruby, and Groovy; or other programming languages. This program code can run entirely on the user's computer, or as a standalone software package on the user's computer, or partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the latter case, the remote computer can be connected to the user's computer via any network, such as a local area network (LAN) or wide area network (WAN), or connected to an external computer (e.g., via the Internet), or in a cloud computing environment, or used as a service such as Software as a Service (SaaS).

[0066] Furthermore, unless expressly stated in the claims, the order of processing elements and sequences, the use of numbers and letters, or other names described in this application are not intended to limit the order of the processes and methods of this application. Although some currently considered useful embodiments of the invention have been discussed in the foregoing disclosure by way of various examples, it should be understood that such details are for illustrative purposes only, and the appended claims are not limited to the disclosed embodiments; rather, the claims are intended to cover all modifications and equivalent combinations that conform to the substance and scope of the embodiments of this application. For example, although the implementation of the various components described above can be embodied in a hardware device, it can also be implemented as a purely software solution, such as an installation on an existing server or mobile device.

[0067] Similarly, it should be noted that, in order to simplify the description of the present application and thus aid in the understanding of one or more embodiments of the invention, the foregoing description of the embodiments of the present application sometimes combines multiple features into a single embodiment, drawing, or description thereof. However, this approach of the present application should not be construed as reflecting an intention that the claimed subject matter requires more features than expressly recited in each claim. Rather, the subject of the invention should possess fewer features than in any single embodiment described above.

Claims

1. A method for optimizing the configuration of a drill bit coupled with rock in a drill-and-blast tunnel boring machine, characterized in that, include: S1: Determine the variable design parameters of the drill bit on the rock drilling rig; S2: Based on the aforementioned variable design parameters, a full factorial design method combined with orthogonal array reduction technology is used to set up multiple sets of drill tooth configuration comparison working conditions; S3: For each set of drill bit configuration comparison working conditions, establish a three-dimensional geometric model of the drill bit, and construct a refined finite element coupled model that includes the drill bit and the core drilling area of ​​the surrounding rock. S4: Extract and analyze the surrounding rock mechanical response index, key drilling parameters, and drill bit response index under each working condition from the numerical simulation results of the refined finite element coupled model. S5: Based on the extracted surrounding rock mechanical response index, drilling key parameters and drill bit response index, calculate and analyze the quantitative evaluation index under each working condition; S6: Analyze the cloud map damage area of ​​the numerical simulation results, extract and calculate the connected domain shape features of the damage area, and determine the point-line-surface rock breaking topology pattern corresponding to each working condition based on the actual rock breaking damage morphology. S7: Using the calculated quantitative evaluation indicators and the determined rock-breaking topology as inputs, and combining engineering experience, construct a comprehensive evaluation model that dynamically adjusts the weights of the quantitative evaluation indicators based on the rock-breaking topology. S8: The comprehensive evaluation model is used to make a preliminary score for each working condition. The preliminary score is corrected by introducing a penalty factor in combination with the two engineering feasibility factors of chip removal smoothness and anti-clogging performance. The score is sorted according to the corrected comprehensive score, and the optimal combination of drill tooth configuration parameters that takes into account rock breaking performance and engineering practicality under the target surrounding rock conditions is output.

2. The method for optimizing the configuration of a drill bit in the drill-and-blast tunnel boring machine-rock coupling method according to claim 1, characterized in that, In S1, the variable design parameters include the drill bit shape, the number of external teeth, the number of internal teeth, the tooth diameter, and the spatial layout of the internal and external teeth. The drill bit shape is selected as spherical or conical teeth according to the characteristics of the target surrounding rock. Each parameter is taken at three to five levels based on engineering experience. The layout of the internal and external teeth includes the internal teeth being evenly distributed at the center and the external teeth being evenly distributed around the circumference.

3. The method for optimizing the configuration of a drill bit in a drill-and-blast tunnel boring machine-rock coupling method according to claim 2, characterized in that, In S2, the working conditions of the drill tooth configuration are designed by comprehensively considering the interaction of all factors such as the shape of the drill tooth, the number of external teeth, the number of internal teeth, the tooth diameter, and the spatial layout of the internal and external teeth. Orthogonal arrays are used to reduce the working conditions generated by the full factorial design, thereby reducing the amount of calculation while ensuring that each factor and the interaction between factors can be fully analyzed.

4. The method for optimizing the configuration of a drill bit in a drill-and-blast tunnel boring machine-rock coupling method according to claim 1, characterized in that, In S3, all model components in the refined finite element coupled model are simulated using solid elements, and local mesh refinement is implemented in the core drilling area of ​​the refined finite element coupled model to improve the accuracy of stress calculation. All external boundaries of the refined finite element coupled model are subject to fixed constraints. The drill bit in the refined finite element coupled model is defined as a rigid body, and drilling pressure and rotation speed consistent with actual construction are applied to reproduce the real dynamic drilling loading conditions.

5. The method for optimizing the configuration of a drill bit in a drill-and-blast tunnel boring machine-rock coupling method according to claim 1, characterized in that, In S4, the surrounding rock mechanical response indicators include plastic strain, stress, and shear failure; the key drilling parameters include drilling acceleration, drilling displacement, and drilling speed; and the drill bit response indicators include reaction force and reaction torque. The above three types of indicators are used to jointly characterize the dynamic interaction process between the drill bit and the surrounding rock.

6. The method for optimizing the configuration of a drill bit in the drill-and-blast tunnel boring machine-rock coupling method according to claim 1, characterized in that, In S5, the quantitative evaluation indicators include the proportion of surrounding rock damage volume, average drilling torque, and average specific energy. The proportion of surrounding rock damage volume is obtained by post-processing and statistical analysis of the numerical simulation results. The average drilling torque is the arithmetic mean calculated from the drilling torque time history curve of the drill bit in the steady-state drilling stage. The steady-state drilling stage is the period in the torque time history curve where the fluctuation amplitude is less than 10% of the average value.

7. The method for optimizing the configuration of a drill bit in the drill-and-blast tunnel boring machine-rock coupling method according to claim 1, characterized in that, In S6, the rules for determining the point-line-surface rock breaking topology are as follows: when the connected domains of the damaged area show a circular independent distribution feature, it is determined to be a point rock breaking mode; when the connected domains of the damaged area show a continuous linear distribution feature, it is determined to be a linear rock breaking mode; when the connected domains of the damaged area show a cross-network distribution feature, it is determined to be a surface rock breaking mode.

8. The method for optimizing the configuration of a drill bit in the drill-and-blast tunnel boring machine-rock coupling method according to claim 7, characterized in that, In S7, the comprehensive evaluation model adopts a weighted scoring method. Based on the differences in sensitivity of different rock breaking topology modes to each quantitative evaluation index, the corresponding weight adjustment coefficients are determined in advance through engineering experience. When a certain working condition is determined to be a specific rock breaking topology mode, the weight of the corresponding quantitative evaluation index in the weighted scoring function is automatically multiplied by the corresponding adjustment coefficient.

9. The method for optimizing the configuration of a drill bit in a drill-and-blast tunnel boring machine-rock coupling method according to claim 7, characterized in that, In S8, for the working condition of planar rock breaking mode, corresponding scoring penalty factors are set according to its chip removal difficulty level and anti-clogging performance level, and the preliminary comprehensive score of the working condition is deducted.

10. The method for optimizing the configuration of a drill bit in a drill-and-blast tunnel boring machine-rock coupling method according to claim 1, characterized in that, In S8, the optimal combination of drill tooth configuration parameters output includes the drill tooth shape, number of external teeth, number of internal teeth, tooth diameter, and spatial layout of internal and external teeth. It also includes the expected specific energy range and average torque range corresponding to the parameter combination, providing a direct basis for on-site drill bit manufacturing and construction parameter adjustment.

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