Smooth blasting method containing induction structure and self-locking cartridge bag

Abstract

The invention provides a smooth blasting method containing an induction structure and a self-locking cartridge bag, and relates to the technical field of blasting control in geotechnical engineering and mineral engineering. According to the method, a hole arrangement optimization algorithm oriented to rock mass structure characteristics is constructed, an hourglass type charging structure with a multi-section energy zoning function is designed, a pre-blasting induced crack forming technology and an in-hole cartridge bag self-locking positioning mechanism are integrated, accurate control and quality improvement of the whole smooth blasting process are achieved, and the smooth blasting quality is improved. And smooth surface continuity and blasting consistency are remarkably improved, and the technical requirements of modern rock mass control excavation for high precision, low disturbance and high forming quality are met. The method is suitable for scenes with high requirements on rock mass disturbance control and forming precision, such as tunnel construction, mine roadway tunneling, side slope forming, ore body boundary control and the like, and has wide engineering applicability and popularization value.

Description

Technical Field

[0001] The present invention relates to controlled blasting technology in geotechnical engineering and mining engineering, in particular to the field of smooth blasting methods and charge structure optimization. Specifically, it is a precision-controlled smooth blasting method that integrates induced crack control, self-locking positioning charges and a multi-stage explosion pressure control structure. Background Art

[0002] Smooth blasting is a refined blasting technique designed to control rock disturbance and create a smooth boundary. It is widely used in engineering scenarios such as tunnel construction, mining, slope stripping, and roadway excavation. Its basic principle is to set up a circle of control holes around the main blasting area. Through appropriate drilling arrangements, interval charging, shock-absorbing detonation, and controlled sealing, the blasting energy is precisely released within the controlled area. This fragments the rock mass while maintaining the integrity of the smooth side to the greatest extent possible, forming a regular, continuous, and minimally damaging blasting boundary.

[0003] However, in actual engineering applications, traditional smooth blasting methods still face a number of technical challenges. First, hole layout design relies heavily on experience, and there is a lack of hole layout algorithms that can be adaptively optimized according to rock mass structure, making it difficult to formulate precise hole layout parameters for different geological conditions. Secondly, the traditional "explosive-air gap-explosive" charging structure is highly dependent on conditions such as hole wall smoothness and borehole verticality. In complex rock masses, problems such as segment slippage, charge displacement, and energy transfer disorder often occur, resulting in large fluctuations in the quality of smooth surface forming. Furthermore, the existing blasting process lacks effective means to control induced cracks in the hole. After the blast, the direction of main crack propagation is often uncontrolled, and local tearing, breaking, and instability of the smooth surface are frequent. In addition, in deep hole or multi-stage blasting, the charge is prone to sliding or rotating, affecting the blasting accuracy and coordination between segments, seriously restricting the improvement of the level of smooth surface control blasting.

[0004] Utility model patent publication number CN218380685U provides an explosive energy control device for long strips of explosives used for smooth blasting. The device comprises a focusing tube body and a pair of metal sheets. The focusing tube body is hollow and has a central cavity with an hourglass-shaped cross-section. The cavity has two V-shaped inner walls and two straight inner walls, the two V-shaped inner walls facing each other, and the two straight inner walls facing each other and being parallel to each other. The metal sheets are V-shaped or curved, with both sides of each metal sheet fixed and attached to the middle of the corresponding V-shaped inner wall. However, this device suffers from technical issues such as inaccurate energy release control, unstable charge structure, and poor post-blast smooth finish quality.

[0005] In view of this, it is necessary to study a smooth blasting method containing an induction structure and a self-locking charge to solve the above technical problems. Summary of the Invention

[0006] In order to overcome the problems existing in the existing smooth blasting technology, such as unreasonable blasthole arrangement, inaccurate energy release control, unstable charge structure and poor quality of smooth surface forming after blasting, the present invention proposes a smooth blasting method containing an induction structure and a self-locking charge. By constructing a hole layout optimization algorithm oriented to rock structure characteristics, designing an hourglass-shaped charge structure with multi-segment energy partitioning function, integrating pre-blasting induced crack formation technology and in-hole charge self-locking positioning mechanism, precise control and quality improvement of the entire smooth blasting process are achieved.

[0007] The present invention provides a smooth blasting method including an induction structure and a self-locking charge, comprising the following steps: S1: Build a hole layout optimization algorithm tailored to rock mass structural characteristics, including rock mass structure identification and parameter extraction, hole layout design variable modeling and control condition setting, as well as responsive hole layout construction and dynamic adjustment of the scheme; S2: Design an hourglass-shaped charge structure with multi-segment energy partitioning and a self-locking positioning structure for the charge inside the hole, thus constructing a charge structure that integrates energy partitioning and self-locking positioning. S3, constructing a multi-mode fracture induction structure for directional fracture control before blasting, with induction methods including structural induction and / or hole-laying guidance; S4, finally, smooth blasting with high profile continuity, low side wall disturbance and high operating efficiency is carried out.

[0008] As a further improvement of the present invention, in step S1, the specific process of rock mass structure identification and parameter extraction in step S11 is as follows: First, the rock mass structural parameters of the blasting area are obtained through drill core interpretation, joint line survey, in-hole videography, and acoustic detection techniques, including joint density, main controlling structural surface inclination angle θ, dip φ, lithology soft and hard indexes, and structural surface spatial extension characteristic parameters. Then, the acquired parameter data are normalized to construct a two-dimensional or three-dimensional structural surface distribution map, and the blasting zones are divided according to the main controlling direction of the joints.

[0009] As a further improvement of the present invention, in step S1, the specific process of hole arrangement design variable modeling and control condition setting in step S12 is: constructing a parameter calculation system based on rock mass structure construction index-energy response interval-hole arrangement projection fitting, and establishing a hole arrangement parameter system and control constraint rules, including: S121, construction of rock mass structure index R s ; S122, calculate the blasting energy response range R b ; S123, hole arrangement parameter mapping relationship and hole arrangement projection fitting.

[0010] As a further improvement of the present invention, in step S121, the rock mass structure construction index R s The expression is: ; Among them, J v is the joint volume density; ρ s is the structural surface tendency concentration coefficient; RQD It is an indicator of rock mass integrity; α1, α2, and α3 are the mine rock mass adjustment coefficients, which are assigned according to the lithologic characteristics of the area.

[0011] As a further improvement of the present invention, in step S122, the blasting energy response interval R b The calculation formula is: ; Where E is the effective blast energy input of a single hole, which is calculated based on the hole depth, line charge density and charging method; λs is the structural influence coefficient, which is determined empirically based on the structural integrity of the rock mass; b1 is the rock mass control coefficient, which is determined according to the elastic longitudinal wave velocity of the rock mass and the basic physical properties of the rock mass.

[0012] As a further improvement of the present invention, in step S123, the process of the hole arrangement parameter mapping relationship and the hole arrangement projection fitting is as follows: Project the hole layout parameters [a, b, h, α, γ] into the response interval R b Function set: 1) Calculation of hole spacing a: The hole spacing is used to control the energy overlap between adjacent blast holes in the smooth direction. It should be set based on the coupling relationship between the structural direction and the explosion pressure propagation direction. The expression is: ; Among them, k d is the coupling adjustment coefficient, which indicates the maximum tolerable degree of optical wavefront crossover within the effective radius of the explosion pressure. The recommended value is 0.6~0.8, which is determined by construction experience. θ is the angle between the adjacent hole directions and the main control structure surface, in degrees, ranging from 0° to 90°, and is used to adjust the energy offset caused by joint guidance; 2) Calculation of row spacing b: The row spacing determines the interference area between the upper and lower rows of blasting, and should take into account the explosion pressure attenuation rate and the structural surface influence coefficient. The expression is: ; k sThe coverage factor of the explosion pressure effect is recommended to be 0.7~1.0, which can be modified according to the complexity of the structure; 3) Calculation of hole depth h: The hole depth must cover the structural control area below the design contour surface to avoid the risk of subsequent spalling due to "unbroken joints". The expression is: ; in, H j The depth of the bottom boundary of the layer with the strongest joint development is determined by the field geological model; δ h To guide the extension depth, 0.3-0.5 m is generally used to ensure complete penetration of the structural surface; 4) Hole inclination angle α and hole direction γ setting: To improve the ability of cracks to expand in the preset smooth direction, it is necessary to make the blasthole direction form a sufficient intersection angle with the main controlling joint. The expression is: ; in, β is the inclination angle of the structural surface; Δ α , Δ γ It is the direction adjustment angle, which is generally controlled within the range of ±15°.

[0013] As a further improvement of the present invention, in step S1, the specific process of the responsive hole layout construction and dynamic adjustment of the plan in step S13 is as follows: after the hole layout parameters are determined, a construction diagram containing hole positions, hole directions, angles, and structural partition identifiers is output to facilitate on-site layout and drilling; during the construction process, if joint strike deviations, rock property mutations, hole collapse, hole inclination, etc. are encountered, adjustments can be made according to preset rules, and the adjustment method is as follows: When the joint direction deviation exceeds the limit, adjust the hole direction to maintain the intersection angle; The lithology change is optimized by adjusting the length of the void section to release the explosive pressure; When the hole is abnormal, compensation holes can be arranged or the charge structure can be corrected; When the hole position deviation exceeds the limit, the adjacent parameters are adjusted in a linked manner to prevent energy interference; All adjustments are recorded in the hole layout response table, which serves as the basis for post-blast evaluation and subsequent optimization, and establishes a closed-loop control system between hole layout design and actual construction.

[0014] As a further improvement of the present invention, in step S2, the hourglass-shaped charge structure with a multi-segment energy partitioning function is hourglass-shaped or dumbbell-shaped as a whole, and is composed of a central cylindrical main charge area and ellipsoidal cavity areas at both ends thereof. It is prefabricated using a flexible composite shell, and the internal partitions are continuous and integrated; The central cylindrical main charging area is filled with high-energy-density explosives and serves as the main crushing section. Its length is customized according to the joint distribution and the depth of the control area; the ellipsoidal cavity areas at both ends are hollow shells or filled with low-density slow-release materials. No explosives are loaded, forming a natural "explosive-air-explosive" space sequence.

[0015] As a further improvement of the present invention, in step S2, the self-locking positioning structure is arranged on the outer edge of the cavity section of the multi-segment functional charge structure, distributed in an annular shape, and is composed of a high-toughness flexible support matrix and high-friction particles embedded in the high-toughness flexible support matrix; The self-locking positioning structure is compressed and attached to the surface of the charge structure during the insertion process of the blast hole, and is elastically released after being pushed to the predetermined position, forming annular contact with the wall of the blast hole; wherein, the high-toughness flexible support matrix provides moderate deformation ability when the wall of the blast hole is irregular, thereby improving the fit; the high-friction particles are embedded in a dotted manner, forming an interface with the wall of the blast hole.

[0016] As a further improvement of the present invention, in step S3, the structural induction type crack control method is suitable for areas with joint groups, obvious structural surfaces or clear crack distribution directions, and artificial control of the crack initiation point is achieved by micro-processing the hole wall or adjusting the charge structure; the structural induction type crack control method adopts one or more combinations of pre-grooving induction method, hole wall weakening treatment method, and eccentric charge induction method.

[0017] As a further improvement of the present invention, the hole layout guidance type fracture control method is suitable for areas with high rock integrity and weak guidance of natural joints. By changing the arrangement relationship of blastholes to form a stress release gradient or directional interference, the crack development path is controlled; the hole layout guidance type fracture control method adopts one or more combinations of hole induction method, water-filled hole pressure guidance method, and micro-delay detonation combination method.

[0018] Beneficial effects: 1. The smooth blasting method provided by this invention, which incorporates an induction structure and self-locking explosive charges, integrates an intelligent hole-placement algorithm driven by geological parameters, an hourglass-shaped flexible charge structure with energy segmentation, multiple pre-blasting crack-inducing methods, and an automatic positioning-capable charge self-locking mechanism. This method can achieve multiple functions, including directional control of blasthole energy, induction of crack propagation paths, and enhanced charge positioning stability, even under complex geological conditions. It significantly improves smooth surface continuity and blasting consistency, meeting the technical requirements of modern rock mass controlled excavation for high precision, low disturbance, and high-quality formation.

[0019] 2. The smooth blasting method provided by the present invention, which includes an induction structure and a self-locking charge, combines intelligent geological structure identification with a hole layout optimization algorithm. Through the innovative design of the charge structure within the blasthole, it achieves directional release of blasting energy and multi-segment energy isolation control. At the same time, it introduces a deployable self-locking positioning structure to ensure the stable positioning of the charge within the hole, preventing slippage and offset. The multi-segment functional charge structure and the self-locking positioning structure are integrated into a design, significantly improving segment loading accuracy and blasting consistency. This method is suitable for scenarios requiring high rock disturbance control and shaping accuracy, such as tunnel construction, mine tunneling, slope shaping, and ore body boundary control. It has broad engineering applicability and promotional value.

[0020] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are specifically listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] To more clearly illustrate the technical solution of the present invention, the following briefly introduces the drawings used in the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be derived from these drawings without inventive effort.

[0022] Figure 1 This is a schematic diagram of the overall process of a smooth blasting method including an induction structure and a self-locking explosive pack provided by an embodiment of the present invention; Figure 2 It is a schematic diagram of an hourglass-shaped charge structure with a multi-segment energy partitioning function provided by an embodiment of the present invention.

[0023] Description of reference numerals: 1. Cylindrical main charge area; 2. Ellipsoidal cavity area; 3. High-friction particles; 4. High-toughness flexible support matrix. DETAILED DESCRIPTION

[0024] The following embodiments of the technical solution of the present invention will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention and are therefore only examples and are not intended to limit the scope of protection of the present invention.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meanings as commonly understood by those skilled in the art to which the present invention belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention; the terms "including" and "having" and any variations thereof in the specification and claims of the present invention and the above-mentioned drawings are intended to cover non-exclusive inclusions.

[0026] In the description of the embodiments of the present invention, technical terms such as "first" and "second" are used solely to distinguish between different objects and should not be understood to indicate or imply relative importance or to implicitly specify the quantity, specific order, or primary and secondary relationship of the technical features indicated. In the description of the embodiments of the present invention, "plurality" means more than two, unless otherwise specifically defined.

[0027] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present invention. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute a separate or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0028] In the description of the embodiments of the present invention, the term "and / or" is simply a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent the following three situations: A exists alone, A and B exists simultaneously, and B exists alone. In addition, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0029] In the description of the embodiments of the present invention, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0030] In the description of the embodiments of the present invention, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of 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 operate in a specific orientation, and therefore cannot be understood as limiting the embodiments of the present invention.

[0031] In the description of the embodiments of the present invention, unless otherwise expressly specified or limited, technical terms such as "installed," "connected," "connect," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and can refer to internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the embodiments of the present invention based on specific circumstances.

[0032] In order to overcome the technical problems existing in the existing smooth blasting technology, such as unreasonable blasthole arrangement, inaccurate energy release control, unstable charge structure and poor quality of smooth surface forming after blasting, the present invention proposes a smooth blasting method containing an induction structure and a self-locking charge. By constructing a hole layout optimization algorithm oriented to the rock structure characteristics, designing an hourglass-shaped charge structure with multi-segment energy partitioning function, integrating pre-blasting induced crack formation technology and in-hole charge self-locking positioning mechanism, precise control and quality improvement of the entire smooth blasting process are achieved.

[0033] See also Figure 1 As shown, the present invention provides a smooth blasting method including an induction structure and a self-locking charge, comprising the following steps: S1, build a hole layout optimization algorithm based on rock mass structural characteristics. The specific process is as follows: The rock mass structure-driven hole layout optimization calculation method provided by this invention is an engineering layout mechanism for constructing a blasting hole layout system for rock mass joint and fissure structures. It mainly converts rock mass structural surface information into hole layout calculation parameters, builds a constraint model based on the blasting disturbance control target, and generates a hole layout plan that is highly adaptable to geological conditions. The calculation method includes multiple core steps such as structure identification, parameter modeling, hole layout solution space generation, plan optimization, and construction response, specifically including: S11, rock mass structure identification and parameter extraction: First, the rock structure parameters of the blasting area are obtained through drill core interpretation, joint line survey, in-hole videography, and acoustic detection, with a focus on extracting parameters such as the joint number density (Jv), the inclination angle θ of the main controlling structural surface, the dip φ, the rock hardness index, and the spatial extension characteristics of the structural surface.

[0034] Then, the collected parameter data are normalized to construct a two-dimensional or three-dimensional structural surface distribution map, and the blasting zones are divided according to the main control direction of the joints, which serves as the basis for the subsequent hole layout direction and density setting.

[0035] S12, hole layout design variable modeling and control condition setting: After the rock mass structure is identified, the spatial distribution pattern of the structural surface needs to be converted into control parameters that can be used for hole layout design. Therefore, a parameter calculation system based on the "rock mass structure construction index-energy response interval-hole layout projection fitting" is constructed. Based on this core relationship, a hole layout parameter system and control constraint rules are established to realize the construction of a reasonable hole layout plan driven by the structure, as follows: S121, rock mass structure index R s : In order to characterize the adaptability of rock mass to the hole arrangement method, a comprehensive structural index Rs was constructed, which is expressed as follows: ; Among them, J v - Joint bulk density; ρ s - structural surface tendency concentration coefficient; RQD - rock mass integrity indicators; α1, α2, α3 - mine rock mass adjustment coefficients, assigned according to the lithologic characteristics of the area.

[0036] The index R s It reflects the "structural complexity" of the rock mass. The larger the value, the more broken the rock mass and the more complex the structure.

[0037] S122, blasting energy response interval R b : Combined with the integrity characteristics of rock mass characterization, the range of the single-hole blasting energy action zone of structural rock mass is described, and an energy response interval model is constructed: ; Where E-single hole effective blast energy input (calculated based on hole depth, line charge density and charging method); λ s - Structural influence coefficient (determined empirically based on the structural integrity of the rock mass); b1-rock mass control coefficient, determined according to the elastic longitudinal wave velocity of the rock mass and the basic physical properties of the rock mass.

[0038] This shows that, under the same energy, the more complex the structure, the smaller the effective propagation range of the blasting energy.

[0039] S123, hole layout parameter mapping relationship: Project the hole layout parameters [a, b, h, α, γ] into the response interval R b Function set: 1) Calculation of hole distance a: The hole spacing is used to control the energy overlap of adjacent blast holes in the smooth surface direction and should be set according to the coupling relationship between the structural direction and the explosion pressure propagation direction.

[0040] ; Among them, k d -coupling adjustment coefficient, which indicates the maximum tolerable degree of light surface wavefront crossing within the effective radius of explosion pressure. The recommended value is 0.6~0.8, which is determined by construction experience. θ-the angle between the adjacent hole direction and the main control structure surface, in degrees, ranging from 0° to 90°, is used to adjust the energy offset caused by joint guidance.

[0041] 2) Calculation of row spacing b: The row spacing determines the interference area between the upper and lower rows of blasting, and should take into account the explosion pressure decay rate and the structural surface influence coefficient.

[0042] ; k s - Coverage factor of explosion pressure action, recommended value is 0.7~1.0, slightly adjusted with the complexity of the structure.

[0043] 3) Calculation of hole depth h: The hole depth must cover the structural control area below the designed contour surface to avoid the risk of subsequent spalling due to "unbroken joints", that is: ; in, H j -The depth to the bottom of the layer with the strongest joint development, determined by the on-site geological model; δ h - The guide extension depth is generally 0.3~0.5m to ensure complete penetration of the structural surface.

[0044] 4) Hole inclination angle α and hole direction γ settings: In order to improve the ability of cracks to expand in the preset smooth direction, it is necessary to ensure that the direction of the blasthole forms a sufficient angle with the main controlling joint.

[0045] ; Among them, β-structural plane inclination angle; Δ α , Δ γ -Direction adjustment angle is generally controlled within the range of ±15°. S13, responsive hole layout construction and dynamic adjustment of plans: To ensure that the hole layout parameters are adaptable to complex rock conditions, after the hole layout parameters are determined, a construction diagram containing hole position, hole direction, angle and structural partition identification is output to facilitate on-site layout and drilling.

[0046] During the construction process, if there are joint deviations, rock property mutations, hole collapse, hole inclination, etc., adjustments can be made according to the preset rules, as follows: When the joint direction deviation exceeds the limit, adjust the hole direction to maintain the intersection angle; The lithology change is optimized by adjusting the length of the void section to release the explosive pressure; When the hole is abnormal, compensation holes can be arranged or the charge structure can be corrected; When the hole position deviation exceeds the limit, the adjacent parameters are adjusted in a linked manner to prevent energy interference.

[0047] The above adjustment rules are generally based on data derived from long-term experience gained in similar mine construction projects. Parameters may vary from mine to mine. However, most are derived from empirical summaries, calculations using empirical formulas, or analogies.

[0048] Specific examples can be found below (not limited to the following adjustment methods): 1. When the measurement found that the angle between the main control direction of the joint and the original hole direction deviated from the designed value of 45° to 25°, approaching the induced cracking limit, the hole direction was adjusted on site by Δγ=+10° to restore it to the range of ≥35°; 2. If the core shows that the lithology of the middle section changes from medium-hard to soft interlayer, the empty section position is moved up and the original empty section length is increased from 0.4m to 0.6m; 3. In response to the 0.3m collapse in the tunnel, a "secondary blast hole" was added 0.5m below the collapsed hole section, and the charge was adjusted to 80% of the main hole; 4. If the hole mouth deviation exceeds the ±5cm control line, the hole angles on both sides will be adjusted by ±3° to avoid uneven explosion pressure in the smooth surface direction causing cracking and deviation.

[0049] All adjustments are recorded in the hole layout response table, which serves as the basis for post-blast evaluation and subsequent optimization, and establishes a closed-loop control system between hole layout design and actual construction.

[0050] S2: Design an hourglass-shaped charge structure with multi-segment energy partitioning and a self-locking positioning mechanism for the charge inside the hole, thus constructing a charge structure that integrates energy partitioning and self-locking positioning. The specific process is as follows: To achieve better smooth blasting results, an integrated charge structure with distributed energy control and self-locking positioning has been designed. This structure features uncoupled energy release and in-hole self-locking positioning. This solves technical issues in traditional smooth blasting, such as large smooth surface disturbances and discontinuous formation caused by unstable charge structures, offset charge segments, and excessive radial coupling. This integrated charge structure achieves zonal control of blasting energy and self-stabilizing charge structure control through geometric design and material functional integration.

[0051] S21, hourglass-shaped charge structure design with multi-segment energy partitioning function: See also Figure 2 As shown, the charge structure is dumbbell- or hourglass-shaped, consisting of a central cylindrical main charge area 1 and ellipsoidal cavity areas 2 at either end. The entire structure is prefabricated using a flexible composite shell, with the internal partitions continuous and integrated. The central cylindrical main charge area 1 is filled with high-energy-density explosives and serves as the primary crushing section. Its length can be customized based on the joint distribution and depth of the control area. The ellipsoidal cavity areas 2 at either end are hollow shells or filled with low-density slow-release materials and are not charged, forming a natural "explosive-air-explosive" spatial sequence.

[0052] Since there is a clear gap between the cavities at both ends and the borehole wall in the radial direction, a clear uncoupled area is formed, which can effectively slow down the transmission intensity of the energy of the main explosion section in the radial direction, control the direct impact of the stress wave on the smooth surface side, reduce destructiveness, and improve the smoothness of the smooth surface forming.

[0053] During loading, the entire structure can be inserted into the blast hole in sequence through a guide rod or a reinforcement rod, avoiding the risk of slippage and dislocation caused by multiple sections of charging, and achieving concentrated energy release and direction control.

[0054] S22, self-locking positioning structure design: See also Figure 2 As shown, in order to ensure the positioning accuracy and stability of the hourglass-shaped charge structure with multi-stage energy partitioning function in the blast hole, the multi-stage functional charge structure is provided with a self-locking positioning structure on the outer edge of the cavity section. The positioning structure is distributed in a ring shape and is composed of a high-toughness flexible support matrix 4 and embedded high-friction particles 3.

[0055] The self-locking positioning structure is compressed and attached to the surface of the charging area during the insertion process of the blast hole, and is elastically released after being pushed to the predetermined position, forming annular contact with the hole wall; among them, the flexible supporting material, namely the high-toughness flexible supporting matrix 4, provides moderate deformation ability when the hole wall is irregular, thereby improving the fit; and the high-friction particles 3 (embedded in a dotted manner) produce an interface fit with the hole wall, significantly increasing the frictional resistance and effectively preventing the charge body from sliding down or rotating axially.

[0056] The self-locking positioning structure is prefabricated on the main body of the charge (an hourglass-shaped charge structure with multi-segment energy partitioning function). No additional operation is required during construction. It is adaptable to different apertures, inclination angles and wall conditions to ensure segment loading accuracy and spatial stability.

[0057] The present invention integrates an hourglass-shaped charging structure with multi-segment energy partitioning function and a self-locking positioning structure to construct an integrated charging structure with energy distribution control and self-locking positioning. It realizes natural uncoupled charging through geometric cavity design, and ensures charging stability through embedded friction composite positioning belt. It is suitable for application scenarios with high requirements on energy release direction control accuracy and segment positioning in smooth blasting, can significantly improve blasting forming quality and contour consistency, and has good engineering promotion value.

[0058] S3: Construct a multi-mode fracture induction structure for directional fracture control before blasting. The specific process is as follows: To improve the controllability of the main crack initiation direction and the consistency of its extension path, and to address the issues of discrete crack initiation points, uneven post-blast contours, and discontinuous smooth surface formation in traditional controlled blasting, a pre-blast directional crack control induction structure system suitable for smooth surface blasting has been proposed. This system pre-processes the blasthole body or surrounding structure before initiation to create a cracking-dominant zone or stress-concentration guiding area. Under the action of blast pressure, cracks are preferentially initiated and connected along the preset direction, thus forming a continuous smooth surface. This structure can be divided into two categories: structural induction and hole-laying guidance, depending on the rock mass integrity and joint distribution.

[0059] S31, structural induction crack control method is applicable to areas with joint groups, obvious structural surfaces or clear crack distribution direction. It can achieve artificial control of crack initiation point by micro-processing the hole wall or adjusting the charge structure. Specifically include: ① Pre-grooving induction method: Use special tools (such as directional core sampling tools) to carve shallow grooves on the smooth side of the blasthole. The groove depth is generally 5-10mm and the groove width is 2-5mm to form a weak surface crack initiation point; ② Hole wall weakening treatment method: inject physical softener (water-soluble swelling material) or apply soft coating material on the hole wall surface in the target direction section to form an asymmetric fracture interface after the explosion pressure is triggered; ③ Eccentric charge induction method: The charge is placed on the side away from the light surface with an eccentricity of 0.3~0.5, and a bias effect is formed through non-uniform coupling to control the biased initiation of the main crack.

[0060] In some specific implementations, the above three methods can be used individually or in combination, and the layout and selection can be carried out according to the lithology and structural adaptability.

[0061] Alternatively, S32, the hole-guiding fracture control method is suitable for areas with high rock integrity and weak natural joint guidance. By changing the arrangement of blastholes, a stress release gradient or directional interference is formed, thereby controlling the fracture development path. Specifically, it includes: ① Hole induction method: Holes are arranged parallel to the main blast hole on the side of the main blast hole with a spacing of 0.3-0.5m. The holes are not charged with explosives or filled with weak dielectric materials. During the transmission of the blasting wavefront, a low-pressure energy window is formed to guide the cracks to converge towards it. ② Water-filled hole pressure-guiding method: Taking advantage of the low compressibility and high wave impedance of water, water-filled holes are set in the target direction, so that the wave energy forms a reflection overlap zone in this area, promoting the preferential extension of the main crack in this direction; ③ Micro-delay detonation combination method: When the main blast holes are arranged in groups, the time difference between the holes on both sides of the smooth surface direction is controlled (such as 2~5ms), and the initial explosion crack disturbance is used to induce the expansion direction of the subsequent blast holes, forming a blast pressure coordinated crack control mode.

[0062] In some specific implementations, the above three methods can be used individually or in combination, and the layout and selection can be carried out according to the lithology and structural adaptability.

[0063] In some specific embodiments, the pre-blasting induced crack control structure of the present invention has the advantages of multi-mode combination, controllable construction process, and adjustable design parameters. It can be flexibly selected and combined according to different rock structure characteristics and blasting targets to achieve concentrated crack starting points, clear directions, and continuous penetration. It has important engineering application value in scenarios with high requirements for surface quality, such as high slope renovation and tunnel contour forming.

[0064] S4, loading the charge structure of step S2 into the blasthole, and finally performing smooth blasting with high profile continuity, low side wall disturbance and high operation efficiency.

[0065] In summary, the present invention provides a smooth blasting method containing an induction structure and a self-locking charge, which relates to the field of controlled blasting technology in geotechnical engineering and mining engineering. This method achieves precise control and quality improvement of the entire smooth blasting process by constructing a hole layout optimization algorithm oriented to rock structure characteristics, designing an hourglass-shaped charge structure with a multi-segment energy partitioning function, integrating pre-blasting induced crack formation technology and an in-hole charge self-locking positioning mechanism, significantly improving the smooth surface continuity and blasting consistency, and meeting the technical requirements of modern rock control excavation for high precision, low disturbance, and high forming quality. It is suitable for scenarios with high requirements for rock disturbance control and forming accuracy, such as tunnel construction, mine tunneling, slope forming, and ore boundary control, and has wide engineering applicability and promotion value.

[0066] It should be noted that the present invention is not limited to the above-mentioned embodiments. The above-mentioned embodiments are merely examples, and any embodiments having substantially the same structure and effect as the technical concept within the scope of the technical solution of the present invention are all included in the technical scope of the present invention. In addition, without departing from the scope of the present invention, other embodiments that can be conceived by those skilled in the art and that combine some of the constituent elements in the embodiments are also included in the scope of the present invention.

Claims

1. A smooth blasting method with an induction structure and a self-locking charge, characterized in that: The steps include: S1: Build a hole layout optimization algorithm tailored to rock mass structural characteristics, including rock mass structure identification and parameter extraction, hole layout design variable modeling and control condition setting, as well as responsive hole layout construction and dynamic adjustment of the scheme; S2: Design an hourglass-shaped charge structure with multi-segment energy partitioning and a self-locking positioning structure for the charge inside the hole, thus constructing a charge structure that integrates energy partitioning and self-locking positioning. S3, constructing a multi-mode fracture induction structure for directional fracture control before blasting, with induction methods including structural induction and / or hole-laying guidance; S4, loading the charge structure of step S2 into the blasthole, and implementing smooth blasting with high profile continuity, low side wall disturbance and high operation efficiency.

2. A smooth blasting method with an induction structure and a self-locking charge according to claim 1, characterized in that: In step S1, the specific process of rock mass structure identification and parameter extraction in step S11 is as follows: First, the rock mass structural parameters of the blasting area are obtained through drill core interpretation, joint line survey, in-hole videography, and acoustic detection techniques, including joint density, main controlling structural surface inclination angle θ, dip φ, lithology soft and hard indexes, and structural surface spatial extension characteristic parameters. Then, the acquired parameter data are normalized to construct a two-dimensional or three-dimensional structural surface distribution map, and the blasting zones are divided according to the main controlling direction of the joints.

3. A smooth blasting method with an induction structure and a self-locking charge according to claim 1, characterized in that: In step S1, the specific process of hole arrangement design variable modeling and control condition setting in step S12 is: constructing a parameter calculation system based on rock mass structure construction index-energy response interval-hole arrangement projection fitting, and establishing a hole arrangement parameter system and control constraint rules, including: S121, construction of rock mass structure index R s ; S122, calculate the blasting energy response range R b ; S123, hole arrangement parameter mapping relationship and hole arrangement projection fitting.

4. A smooth blasting method with an induction structure and a self-locking charge according to claim 3, characterized in that: In step S121, the rock mass structure construction index R s The expression is: ； Among them, J v is the joint volume density; ρ s is the structural surface tendency concentration coefficient; RQD It is an indicator of rock mass integrity; α1, α2, and α3 are mine rock mass adjustment coefficients, which are assigned based on regional lithologic characteristics.

5. A smooth blasting method with an induction structure and a self-locking charge according to claim 4, characterized in that: In step S122, the blasting energy response interval R b The calculation formula is: ； Where E is the effective blast energy input of a single hole, which is calculated based on the hole depth, line charge density and charging method; λs is the structural influence coefficient, which is determined empirically based on the structural integrity of the rock mass; b1 is the rock mass control coefficient, which is determined according to the elastic longitudinal wave velocity of the rock mass and the basic physical properties of the rock mass.

6. A smooth blasting method with an induction structure and a self-locking charge according to claim 5, characterized in that: In step S123, the process of the hole arrangement parameter mapping relationship and hole arrangement projection fitting is as follows: Project the hole layout parameters [a, b, h, α, γ] into the response interval R b Function set: (1) Calculation of hole spacing a: The hole spacing is used to control the energy overlap between adjacent blast holes in the smooth surface direction. It should be set based on the coupling relationship between the structural direction and the explosion pressure propagation direction. The expression is: ； Among them, k d is the coupling adjustment coefficient, which indicates the maximum tolerable degree of optical wavefront crossover within the effective radius of the explosion pressure. The recommended value is 0.6~0.8, which is determined by construction experience. θ is the angle between the adjacent hole directions and the main control structure surface, in degrees, ranging from 0° to 90°, and is used to adjust the energy offset caused by joint guidance; (2) Calculation of row spacing b: The row spacing determines the interference area between the upper and lower rows of blasting. It should take into account the blast pressure attenuation rate and the structural surface influence coefficient. The expression is: ； k s The coverage factor of the explosion pressure effect is recommended to be 0.7~1.0, which can be modified according to the complexity of the structure; (3) Calculation of hole depth h: The hole depth needs to cover the structural control area below the design contour surface to avoid the risk of subsequent spalling due to "unbroken joints". The expression is: ； in, H j The depth of the bottom boundary of the layer with the strongest joint development is determined by the field geological model; δ h To guide the extension depth, 0.3-0.5 m is generally used to ensure complete penetration of the structural surface; (4) Hole inclination angle α and hole direction γ setting: In order to improve the ability of cracks to expand in the preset smooth direction, it is necessary to make the blasthole direction form a sufficient intersection angle with the main controlling joint. The expression is: ； in, β is the inclination angle of the structural surface; Δ α , Δ γ It is the direction adjustment angle, which is generally controlled within the range of ±15°.

7. A smooth blasting method with an induction structure and a self-locking charge according to claim 1, characterized in that: In step S1, the specific process of responsive hole layout construction and dynamic adjustment of the plan in step S13 is as follows: after the hole layout parameters are determined, a construction diagram containing hole positions, hole directions, angles, and structural partitioning marks is output to facilitate on-site layout and drilling; during the construction process, if joint strike deviations, rock type mutations, hole collapses, hole inclinations, etc. are encountered, adjustments can be made according to preset rules, and the adjustment method is as follows: When the joint direction deviation exceeds the limit, adjust the hole direction to maintain the intersection angle; The lithology change is optimized by adjusting the length of the void section to release the explosive pressure; When the hole is abnormal, compensation holes can be arranged or the charge structure can be corrected; When the hole position deviation exceeds the limit, the adjacent parameters are adjusted in a linked manner to prevent energy interference; All adjustments are recorded in the hole layout response table, which serves as the basis for post-blast evaluation and subsequent optimization, and establishes a closed-loop control system between hole layout design and actual construction.

8. The smooth blasting method with an induction structure and a self-locking charge according to claim 1, characterized in that: In step S2, the hourglass-shaped charge structure with multi-segment energy partitioning function is composed of a central cylindrical main charge area and ellipsoidal cavity areas located at both ends of the central cylindrical main charge, and is prefabricated using a flexible composite shell, with the internal partitions being continuous and integrated; The central cylindrical main charging area is filled with high-energy-density explosives and serves as the main crushing section. Its length is customized according to the joint distribution and the depth of the control area. The ellipsoidal cavity areas at both ends are hollow shells or filled with low-density slow-release materials. No explosives are charged, forming a natural "explosive-air-explosive" spatial sequence.

9. A smooth blasting method with an induction structure and a self-locking charge according to claim 8, characterized in that: In step S2, the self-locking positioning structure is arranged on the outer edge of the cavity section of the hourglass-shaped charge structure with multi-segment energy partitioning function, distributed in an annular shape, and is composed of a high-toughness flexible support matrix and high-friction particles embedded in the high-toughness flexible support matrix; The self-locking positioning structure is compressed and attached to the surface of the charge structure during the insertion process of the blast hole, and is elastically released after being pushed to the predetermined position, forming annular contact with the wall of the blast hole; wherein, the high-toughness flexible support matrix provides moderate deformation ability when the wall of the blast hole is irregular; the high-friction particles are embedded in a dotted manner, forming an interface with the wall of the blast hole.

10. A smooth blasting method with an induction structure and a self-locking charge according to claim 2, characterized in that: In step S3, the structural induction crack control method is applicable to areas with joint groups, obvious structural surfaces or clear crack distribution directions, and the crack initiation point is artificially controlled by micro-processing the hole wall or adjusting the charge structure; the structural induction crack control method adopts one or a combination of pre-grooving induction method, hole wall weakening treatment method, and eccentric charge induction method; The hole-layout guidance fracture control method is suitable for areas with high rock integrity and weak natural joint guidance. By changing the arrangement of blastholes, a stress release gradient or directional interference is formed, thereby controlling the crack development path. The hole-layout guidance fracture control method adopts one or more combinations of hole induction method, water-filled hole pressure guidance method, and micro-delay detonation combination method.

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