A method for directional blasting recovery of point columns in steeply inclined empty space

Abstract

The application discloses a method for directional blasting recovery of point column in steeply inclined goaf, and belongs to the field of mining engineering, and comprises the following steps: detecting three-dimensional form parameters of the point column in the goaf; excavating a connecting roadway through the goaf; constructing a blast hole from the goaf to the point column; charging the blast hole and initiating the blasting to fall the ore; and loading the ore into a car through an ore leakage funnel in the connecting roadway and transporting the ore out of the mining field. By detecting the three-dimensional form parameters of the point column in the goaf, the safety of the recovery work is improved by directly avoiding exposing personnel to the collapse environment of the goaf. By excavating the connecting roadway through the goaf, constructing the blast hole from the outside to the point column and charging and initiating the blasting, the problem of exposing personnel in the operation stage is solved, and the safety of the point column recovery is improved. By cooperating the connecting roadway through the goaf with the ore loading into the car, the risk of exposing personnel and equipment to the goaf in the ore transfer stage is solved, so that the whole process is operated outside, and the problem of exposing personnel and equipment to the goaf in the point column recovery work is avoided.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of mine engineering, and particularly relates to a method for directional blasting recovery of point pillars in a steeply inclined goaf. BACKGROUND

[0002] In mining engineering, a point pillar is a regularly arranged ore body or rock pillar reserved for supporting the roof in underground mining, usually in the shape of a square or rectangle, with a size of 3-7 meters (for thin ore bodies) to 5-10 meters (for thick ore bodies), and a center-to-center distance of 8-14 meters. Its core function is to form a support structure by locally leaving ore, preventing the collapse of the roof in the goaf, and ensuring safety. Point pillars are commonly found in room-and-pillar mining and point-pillar filling mining methods, and are widely used in gently inclined medium-thick ore bodies. In steeply inclined ore bodies, the proportion of point pillars to ore can reach 15%-20%, and the original goaf is too narrow to implement conventional recovery techniques, with a permanent loss rate far exceeding the design value. Existing recovery techniques such as the artificial false lane method require personnel to enter the goaf for exposed operations, which violates safety regulations.

[0003] Therefore, there is an urgent need for a personnel-free point pillar recovery method for narrow goafs. SUMMARY

[0004] In view of the technical problems in the background art, the present application provides a method for directional blasting recovery of point pillars in a steeply inclined goaf, comprising:

[0005] detecting three-dimensional morphological parameters of point pillars in the goaf;

[0006] driving a connecting roadway through the vein;

[0007] constructing blast holes from the goaf to the point pillars;

[0008] charging explosives into the blast holes and detonating the ore;

[0009] loading the ore into a car through an ore discharge funnel in the connecting roadway and transporting it out of the mine.

[0010] In some embodiments, in the step of constructing blast holes from the goaf to the point pillars, it further comprises:

[0011] transporting a medium-depth hole drilling machine to the end of the connecting roadway through the vein or into the connecting roadway through the vein;

[0012] In some embodiments, after the step of transporting a medium-depth hole drilling machine to the end of the connecting roadway through the vein or into the connecting roadway through the vein, the step of constructing blast holes from the goaf to the point pillars further comprises:

[0013] using the medium-depth hole drilling machine to construct a lateral fan-shaped blast hole group until the blast hole length reaches the junction of the ore body and the upper wall rock;

[0014] In some embodiments, in the step of detecting three-dimensional morphological parameters of point pillars in the goaf, it further comprises:

[0015] The goaf formed by the shallow hole shrinkage method is scanned by the three-dimensional laser scanning technology to generate a point cloud model, and the position, size and shape of the point column are captured.

[0016] In some embodiments, after the three-dimensional shape parameters of the point column in the goaf are detected, the method for directional blasting and recovery of the point column in the steeply inclined goaf further comprises:

[0017] The three-dimensional coordinates of the point column are projected onto the horizontal plane to determine the corresponding area in the cross-vein roadway.

[0018] In some embodiments, in the cross-vein connecting roadway, it comprises:

[0019] The cross-vein connecting roadway is excavated from the cross-vein roadway to the projection point.

[0020] In some embodiments, in the cross-vein connecting roadway, it comprises:

[0021] The cross-vein connecting roadway is excavated to the projection boundary position of the point column.

[0022] In some embodiments, in the cross-vein connecting roadway, it comprises:

[0023] The cross-vein connecting roadway is excavated to the projection boundary position of the point column, and the along-vein drill roadway is constructed in the width direction of the point column projection, and the along-vein drill roadway boundary beyond the width direction of the point column projection.

[0024] In some embodiments, in the charging and detonating of the blast hole and the ore falling, it comprises:

[0025] The point column ore body section is charged, the lower wall rock section is left empty, and the explosive is blocked at the junction of the explosive and the wall rock section.

[0026] In some embodiments, in the charging and detonating of the blast hole and the ore falling, it further comprises:

[0027] The explosives in the lateral fan-shaped medium-deep hole are detonated in a millisecond blasting mode.

[0028] The application provides a method for directional blasting recovery of point columns in a steeply inclined goaf, which avoids the risk that personnel needs to enter the goaf during the detection stage by detecting the three-dimensional morphological parameters of the point columns in the goaf, and then directly avoids the exposure of personnel to the collapse environment of the goaf by replacing manual surveying with non-contact data acquisition, thereby improving the safety of the recovery work; the exposure problem of personnel during the operation stage is solved by excavating a connecting roadway through the vein, constructing blast holes to the point columns from the outside and detonating, and then the directional blasting ore falling is realized by constructing a physical isolation channel to make the equipment operate outside the goaf, and the personnel is kept away from the inside of the goaf by using the roadway barrier, so that the possibility of collapse accidents is avoided from the source, and the safety of the point column recovery is improved; the risk that personnel and equipment need to enter the goaf during the ore transportation stage is solved by the cooperation of the vein connecting roadway and the ore loading and unloading, and then the ore is directly collected to the vein roadway for loading and unloading after blasting by preinstalling an integrated mining and transportation path, and the need for temporary system construction is reduced by using the dual function of the roadway, so that the whole process is operated outside, and the problem that personnel and equipment are exposed to the goaf in the point column recovery work is avoided.

[0029] The above description is only a summary of the technical scheme of the application, in order to more clearly understand the technical means of the application, the specific embodiments of the application can be implemented according to the content of the specification, and in order to make the above and other purposes, characteristics and advantages of the application more obvious and easy to understand, the following will specifically describe the embodiments of the application. BRIEF DESCRIPTION OF DRAWINGS

[0030] In order to more clearly illustrate the technical scheme of the application, the drawings used in the application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without creating laborious work.

[0031] Figure 1 is a structure schematic diagram of a working condition applied in a method for directional blasting recovery of point columns in a steeply inclined goaf provided by an embodiment of the application;

[0032] Figure 2 is a structure schematic diagram of a mining and preparation engineering layout of a working condition applied in a method for directional blasting recovery of point columns in a steeply inclined goaf provided by an embodiment of the application;

[0033] Figure 3 is a schematic diagram of a drilling engineering for a point column applied in a method for directional blasting recovery of point columns in a steeply inclined goaf provided by an embodiment of the application;

[0034] Figure 4 is a schematic diagram of a drilling engineering for a point column with a wider width applied in a method for directional blasting recovery of point columns in a steeply inclined goaf provided by an embodiment of the application;

[0035] Figure 5 is a point column blast hole arrangement schematic diagram of a working condition applied in a method for point column directional blasting recovery in a steeply inclined goaf provided by an embodiment of the present application;

[0036] Figure 6 is a basic flow schematic diagram of a method for point column directional blasting recovery in a steeply inclined goaf provided by an embodiment of the present application;

[0037] Figure 7 is an optimization flow schematic diagram of a method for point column directional blasting recovery in a steeply inclined goaf provided by an embodiment of the present application regarding goaf outward point column construction blast hole;

[0038] Figure 8 is a further optimization flow schematic diagram of a method for point column directional blasting recovery in a steeply inclined goaf provided by an embodiment of the present application regarding goaf outward point column construction blast hole;

[0039] Figure 9 is an optimization flow schematic diagram of a method for point column directional blasting recovery in a steeply inclined goaf provided by an embodiment of the present application regarding detection method;

[0040] Figure 10 is a further optimization flow schematic diagram of a method for point column directional blasting recovery in a steeply inclined goaf provided by an embodiment of the present application regarding detection method;

[0041] Figure 11 is an optimization flow schematic diagram of a method for point column directional blasting recovery in a steeply inclined goaf provided by an embodiment of the present application regarding mining and preparation engineering layout;

[0042] Figure 12 is a further optimization flow schematic diagram of a method for point column directional blasting recovery in a steeply inclined goaf provided by an embodiment of the present application regarding mining and preparation engineering layout;

[0043] Figure 13 is an optimization flow schematic diagram of a method for point column directional blasting recovery in a steeply inclined goaf provided by an embodiment of the present application regarding mining and preparation engineering layout for wider point column mining;

[0044] Figure 14 is a blasting flow schematic diagram of a method for point column directional blasting recovery in a steeply inclined goaf provided by an embodiment of the present application;

[0045] Figure 15 is an optimization flow schematic diagram of blasting of a method for point column directional blasting recovery in a steeply inclined goaf provided by an embodiment of the present application.

[0046] 10, vein crossing roadway; 20, ore drawing hopper; 30, goaf; 40, point pillar; 50, lateral fan medium-length hole; 60, vein crossing connecting roadway; 70, along-vein drill roadway. DETAILED DESCRIPTION

[0047] The embodiments of the technical solutions of the present application will be described in detail below with reference to the drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present application, and therefore only serve as examples, and cannot limit the protection scope of the present application.

[0048] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present application; the terms "include" and "have" and any variations thereof in the specification and claims of the present application and the above description of drawings are intended to cover non-exclusive inclusion.

[0049] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is two or more, unless otherwise explicitly and specifically limited.

[0050] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily all refer to the same embodiment, nor is it necessarily independent or alternative embodiments to other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0051] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the three cases of A alone, A and B together, and B alone. In addition, the character " / " in this paper generally represents that the front and rear associated objects are a "or" relationship.

[0052] In the description of the embodiments of the present application, the term "multiple" refers to two or more (including two), and similarly, "multiple groups" refers to two or more groups (including two groups), and "multiple pieces" refers to two or more pieces (including two pieces).

[0053] In the description of the embodiments of the present application, the orientations or positional relationships indicated by the technical terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the embodiments of the present application.

[0054] In the description of the embodiments of the present application, unless otherwise explicitly specified and limited, the technical terms "mounting", "connection", "connection", "fixing" and the like should be understood in a broad sense, for example, can be fixed connection, can also be detachable connection, or integral; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through an intermediate medium, can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0055] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application will be further described in detail below with reference to the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not to limit the present application.

[0056] Referring to Figure 1 and Figure 2 , an application scenario of a method for directional blasting and recovery of point pillars in a steeply inclined goaf is provided, for example, wherein the point pillars 40 in the goaf 30 are located at the middle of the goaf 30, and a vein roadway 10 is pre-bored at the bottom of the ore body, and the vein roadway 10 is arranged along the trend of the ore body; a ore drop funnel 20 is arranged at the top of the vein roadway 10 to receive the ore dropped by the point pillars 40 and load the ore in the vein roadway 10; the vein roadway 10 is vertically excavated to the vein connecting roadway 60 at the same horizontal plane, which provides an operation surface outside the goaf 30 for the medium-length hole drilling machine, thereby protecting the equipment and personnel safety; when the width of the point pillars 40 is large, a vein rock tunnel 70 is constructed along the trend of the point pillars 40 at the end of the vein connecting roadway 60, thereby avoiding the limitation of the edge hole angle due to insufficient length of the roadway; thereafter, a lateral fan-shaped medium-length hole 50 is directionally constructed by the medium-length hole drilling machine to the position of the point pillars 40 in the goaf, and the edge of the lateral fan-shaped medium-length hole 50 is located at the boundary between the ore body and the hanging wall surrounding rock; the lateral fan-shaped medium-length hole 50 is filled with explosives in the part of the point pillars 40 in the ore body for directional blasting.

[0057] Referring to Figure 6A method for point column directional blasting recovery in steeply inclined gob, comprising:

[0058] S101, detecting the three-dimensional form parameters of the point column in the gob; specifically, the core of this step is to provide spatial data basis for subsequent blasting design, and to replace traditional manual surveying with non-contact data collection to avoid personnel entering the gob for data collection, and to obtain the spatial coordinates, size and inclination angle parameters of the point column by using non-contact measurement means, establish a three-dimensional model to accurately locate the blasting target, and avoid blasting design deviation caused by data loss. For example, a six-rotor unmanned aerial vehicle chassis is equipped with a 360° rotary laser scanning head, and a high-precision inertial guidance system is used to synchronize the flight attitude and scanning angle in real time. The laser scanning head emits pulsed laser beams along the preset spiral trajectory in the gob, and calculates the spatial coordinates by receiving the reflected light signals on the surface of the point column; at the same time, the unmanned aerial vehicle dynamically adjusts the flight path to avoid obstacles by using the obstacle avoidance radar, and finally returns the point cloud data to the ground processing terminal in real time to generate a three-dimensional model of the point column and mark the key inclination angle parameters; for example, a telescopic carbon fiber probe is used to drill into the gob, and a sonar transmitter and a narrow-beam laser scanner are mounted at the end. The sonar module transmits high-frequency sound waves to detect the underwater profile of the point column, and the laser module synchronously scans the exposed surface; by fusing the sound reflection time and laser ranging data, a complete three-dimensional point cloud of the point column is generated and the structure below the water level is automatically marked; for example, a panoramic laser scanner is mounted on a track trolley to cover the boundary of the gob along a preset track. When the robot runs along the track, the scanner emits laser beams in a vertical sector, and the encoder records the movement distance and scanning angle; through multi-station point cloud stitching technology, the blind area is eliminated, and the column diameter, height and deflection angle are extracted by combining the point column boundary recognition algorithm.

[0059] S102, excavating a connecting roadway through the vein; specifically, the purpose of this step is to build a safe operation channel, so that personnel and equipment are always located outside the gob. By excavating a roadway, a path is formed that is laterally connected to the point column, providing a physical channel for the external construction blast hole, while ensuring that the operation surface is isolated from the gob, thereby avoiding the risk of personnel exposure to the collapse of the gob from the source.

[0060] S103, drilling a blast hole from the point column in the gob; specifically, this step is the core operation of remote blasting and mining, and the blast hole is designed based on the three-dimensional form parameters to accurately determine the orientation and depth, so that the blast hole penetrates from the stable surrounding rock zone to the inside of the point column, and the energy transmission direction is controlled by using directional drilling technology, ensuring that the blasting energy is concentrated on the target point column, reducing the disturbance to the surrounding rock, and avoiding personnel entering the gob by drilling an external hole. For easy understanding, as shown in Figure 2 and Figure 3 , a lateral fan-shaped medium-length hole 50 is drilled from the point column 40 in the gob 30 through the vein connecting roadway 60.

[0061] S104, charging and detonating the blast hole to break the ore pillar; specifically, the purpose of this step is to break the ore pillar and control the blasting influence range. By charging the explosives outside and implementing directional detonation, the ore pillar is broken in a predetermined shape, and the controlled caving is realized by using the structural weakness of the ore pillar, thereby reducing the damage of blasting vibration to the stability of the roof of the goaf.

[0062] S105, loading and transporting the ore out of the stope through the ore pass. The purpose of this step is to complete the transportation of the ore from the goaf to the roadway through the pre-installed ore pass system, thereby avoiding personnel or equipment entering the goaf, and improving the safety of the mining work.

[0063] S101 and S103 of the present application have a cooperative relationship: in S101, the spatial coordinates, size and inclination angle parameters of the ore pillar are obtained by non-contact measurement (such as unmanned aerial vehicle laser scanning or probe sonar fusion), and a three-dimensional model is established, and in S103, the position and depth of the blast hole are accurately designed based on the model, so that the blast hole penetrates from the stable surrounding rock zone to the inside of the ore pillar. The cooperative relationship between the two is reflected in the use of data-driven blasting design: the three-dimensional shape parameters provided by S101 provide spatial data basis for the positioning of the blast hole in S103, the energy transmission direction is controlled through directional drilling technology, and the blasting energy is concentrated on the target ore pillar, reducing the disturbance to the surrounding rock, thereby avoiding the problem of blasting design deviation caused by data missing in the goaf, and then avoiding invalid drilling or energy waste, improving the blasting accuracy and resource recovery rate.

[0064] S102 and S103, S104 of the present application have a cooperative relationship: S102 constructs the connecting roadway to form an operation channel laterally connected to the ore pillar, and S103, S104 constructs the blast hole and charges and detonates it from the outside to the ore pillar through the channel. The cooperative relationship between the two is the cooperation of physical channel and operation safety: the roadway serves as an isolation barrier, keeping personnel and equipment outside the goaf, providing a safe physical operation space for S103 and S104. By external construction and internal action through roadway excavation, personnel are avoided from being exposed to the goaf from the source, avoiding the risk caused by collapse. This cooperation avoids the problem that personnel need to enter the dangerous area in the traditional steeply inclined thin ore body ore pillar mining operation, and at the same time provides a stable construction environment for directional blasting and reduces roof instability accidents.

[0065] The S103 and the S104 of the present application have a cooperative relationship: the S103 designs the hole position and depth based on the three-dimensional model, and the S104 implements directional initiation through external charging. The cooperation of the two is that the hole penetration path of the S103 combines the structural weakness of the point column itself (such as the inclination parameter), so that the blasting energy of the S104 can be dissociated in the preset form, the hole guided blasting wave expands along the internal fracture of the point column, and the controllable caving is realized. This cooperation reduces the damage of blasting vibration to the roof of the goaf, avoids the problem of surrounding rock instability caused by energy diffusion, and improves the ore crushing efficiency.

[0066] The S101 and the S105 of the present application have a cooperative relationship: the point column three-dimensional model generated by the S101 marks the key inclination and structural parameters, and the S105 carries out loading and transportation through the ore-drawing hopper passing through the crossheading. The cooperation of the two is that the model guides the resource recovery path: the three-dimensional model accurately locates the spatial distribution of caved ore, providing a basis for the layout of the ore-drawing hopper of the S105. The optimized ore-drawing position is used to ensure that the ore is efficiently collected to the transportation channel. This cooperation solves the problem of low recovery efficiency caused by the scattered distribution of low-grade ore bodies, avoids the entry of equipment into the empty area, and improves the transportation safety.

[0067] The S102 and the S105 of the present application have a cooperative relationship: the crossheading connecting roadway of the S102 provides a preset ore-drawing channel for the S105, and the two form a mining and transportation integration: the roadway is both a blasting operation channel and an ore transfer path, and the transportation route is planned during excavation, so that the ore after blasting can directly enter the crossheading through the crossheading connecting roadway for loading. This cooperation reduces the cost of secondary development, solves the problem of temporary system construction for ore transfer in the goaf, and avoids personnel and equipment entering the goaf, realizing external operation in the whole process.

[0068] The present application solves the risk of personnel entering the goaf during the detection stage by detecting the three-dimensional form parameters of the point column in the goaf, and then replaces manual surveying with non-contact data acquisition, directly avoiding personnel exposure to the collapse environment in the goaf, thereby improving the safety of the recovery work; the cooperation of excavating the crossheading connecting roadway, constructing the hole from the outside of the point column and initiating the explosion solves the problem of personnel exposure during the operation stage, and then the physical isolation channel is constructed to make the equipment operate outside the goaf for directional blasting and ore drawing, and the roadway barrier ensures that personnel are far away from the inside of the goaf, thereby avoiding the possibility of collapse accidents from the source; thereby improving the safety of point column recovery; the cooperation of the crossheading connecting roadway and the ore-drawing loading solves the risk of personnel and equipment entering the goaf during the ore transfer stage, and then the integrated mining and transportation path is preset to realize the direct collection of ore to the crossheading for loading after blasting, and the double function of the roadway reduces the need for temporary system construction, thereby ensuring external operation in the whole process, and avoiding the problem of personnel and equipment exposure in the goaf in the point column recovery work.

[0069] In some embodiments, with reference to Figure 7 In S103, drilling the borehole from the outside of the goaf to the point column in the goaf includes: S1031, transporting the medium-deep hole drilling machine to the end of the cross-vein connecting roadway or into the cross-vein roadway. Specifically, the medium-deep hole drilling machine is positioned at the end of the cross-vein connecting roadway or in the cross-vein roadway, and the physical isolation space formed in advance in the cross-vein connecting roadway is used as a drilling machine transportation channel and an operation platform, so that the drilling machine can complete the directional drilling of the borehole in the stable surrounding rock area, thereby avoiding personnel entering the goaf for drilling operation. This design relies on the isolation effect of the roadway space on the dangerous area of the goaf to limit the drilling operation in the stable external surrounding rock area, and through the relative position relationship between the end of the roadway or the cross-vein roadway and the point column, the borehole is accurately penetrated from the outside to the inside to the target position of the point column, thereby providing an accurate energy transmission path for subsequent directional blasting.

[0070] In some embodiments, with reference to Figure 8 After the medium-deep hole drilling machine is transported to the end of the cross-vein connecting roadway or into the cross-vein roadway, S103, drilling the borehole from the outside of the goaf to the point column in the goaf also includes: S1032, using the medium-deep hole drilling machine to drill lateral fan-shaped borehole groups until the borehole length reaches the junction of the ore body and the hanging wall surrounding rock. The purpose of this step is to build a geometric channel for directional energy transmission, and through the geometric layout of the lateral fan-shaped borehole groups, the blasting energy is accurately focused on the point column area to avoid the disorderly diffusion of energy. Its role is reflected in two aspects: on the one hand, the fan-shaped radial borehole groups cover the cross section of the point column to form a space convergence point of blasting energy, preferentially destroying the weak points in the internal structure of the point column, realizing the "from inside to outside" directional caving, and reducing the impact on the surrounding rock; on the other hand, the borehole length is strictly terminated at the junction of the ore body and the hanging wall surrounding rock, blocking the transmission path of the blasting stress wave to the surrounding rock, limiting the disturbance range from a geometric point of view, forming a natural energy reflection barrier, inhibiting the transmission of stress waves to the goaf roof and floor, and maintaining the stability of the surrounding rock. For example, in combination with Figure 3 or Figure 4 Drilling from the cross-vein connecting roadway 60 into the point column 40 in the goaf 30 and forming lateral fan-shaped medium-deep holes 50.

[0071] In some embodiments, with reference to Figure 9In S101, the point column three-dimensional form parameter of the goaf is detected, including: S1011, using three-dimensional laser scanning technology to scan the goaf formed by the short-hole shrinkage method to generate a point cloud model, and capturing the position, size and form of the point column. The purpose of this step is to build a non-contact sensing system for spatial data of the goaf, and to replace the traditional manual surveying by remote scanning to provide accurate spatial reference for subsequent blasting design, thereby eliminating the necessity of personnel entering the goaf. Specifically, it is holographic acquisition of three-dimensional data: relying on the laser ranging and polar coordinate measurement principle, the surface of the goaf is scanned by a high-speed pulsed laser beam, and the three-dimensional coordinates of each point on the surface of the point column are calculated by receiving the reflected signal; the point cloud model is automatically fitted with the point column boundary and form parameter through a spatial data reconstruction algorithm, non-destructive capture of hidden structures (such as the contour below the water line) is realized, and then the whole goaf is covered by full-face scanning to generate a point cloud model that completely maps the spatial coordinates, geometric dimensions and structure inclination angle of the point column, thereby providing an irreplaceable data basis for directional blasting design.

[0072] In some embodiments, with reference to Figure 10 After S101, the point column three-dimensional form parameter of the goaf is detected, the method for directional blasting recovery of the point column in the steeply inclined goaf further includes: S1012, projecting the three-dimensional coordinates of the point column to the horizontal plane to determine the corresponding area thereof in the crossheading. The purpose of this step is to establish a spatial mapping reference, to locate the distribution area of the caved ore in the crossheading by projecting the three-dimensional coordinates of the point column to the horizontal plane, thereby providing a geometric positioning basis for the closed transportation system, defining the shortest path for ore transfer, and reducing the frequency of equipment movement and the contact with the surrounding rock of the roadway.

[0073] In some embodiments, with reference to Figure 11 In S102, the crossheading connecting roadway is excavated, including: S1021, excavating the crossheading connecting roadway from the crossheading to the projection point. The purpose of this step is to establish a data-driven precise docking mechanism of the physical channel, and to accurately guide the spatial layout of the roadway construction. Specifically, the horizontal projection point obtained in S1012 is taken as the spatial target point, and the crossheading connecting roadway is excavated from the crossheading to ensure that the connecting roadway accurately penetrates to the predetermined position on the side of the point column, thereby creating an adaptive operation space for subsequent blasthole construction; on the other hand, based on the accurate projection point, the excavation of the invalid rock mass is greatly reduced, and only the connecting roadway of the shortest straight line path between the crossheading and the projection point is needed. This not only reduces the mechanical disturbance to the surrounding rock, but also avoids the stability risk of the goaf caused by overbreak or deviation of the roadway.

[0074] In some embodiments, with reference to Figure 12In S102, the tunneling through the vein connecting roadway includes: S1022, tunneling through the vein connecting roadway to the point column projection boundary position. Specifically, after detecting and obtaining the point column shape parameters and generating the horizontal projection, the projection boundary position directly demarcates the maximum contour range of the point column on the horizontal plane. Tunneling the roadway to the boundary position essentially establishes a physical channel and an operation platform for subsequent blasthole construction, enabling the blasthole group to obtain a relatively optimal operation surface to optimize the blasthole angle and blasthole position as much as possible, thereby facilitating the blasting and mining of the point column in the goaf. For example, if the roadway does not reach the projection boundary, the blasthole needs to penetrate thicker rock layers obliquely to cover the point column, which not only increases the drilling difficulty but also disperses the blasting energy; after accurate positioning to the boundary, the blasthole can be directly expanded along the lateral fan shape, ensuring that the explosive energy is concentrated on the point column body, thereby improving the blasting effect. For ease of understanding, refer to Figure 2 Tunneling through the vein connecting roadway 60 from the vein roadway 10 to the point column 40 projection boundary position.

[0075] In some embodiments, refer to Figure 13 In S102, the tunneling through the vein connecting roadway includes: S1023, tunneling through the vein connecting roadway to the point column projection boundary position, and constructing the vein following rock drilling roadway to the vein following rock drilling roadway boundary beyond the point column projection width direction. Specifically, after tunneling through the vein connecting roadway to the point column projection boundary position, the vein following rock drilling roadway is extended along the point column width direction, so that its length exceeds the point column projection boundary, thereby allowing the blasthole to be uniformly arranged at a fan angle pointing to the center of the point column when facing a point column with a larger width, avoiding the limitation of the edge blasthole angle due to insufficient roadway length. For ease of understanding, refer to Figure 2 Tunneling through the vein connecting roadway 60 from the vein roadway 10 to the point column 40 projection boundary position, and then constructing the vein following rock drilling roadway 70 to the vein following rock drilling roadway 70 boundary beyond the point column 40 projection width direction.

[0076] In some embodiments, refer to Figure 14In S104, charging and detonating the blast hole to fall the ore, comprising: S1041, charging in the point column ore body section, leaving the lower wall rock section empty, and using stemming to block at the junction of the explosive and the wall rock section. Specifically, the charging is limited to the point column ore body section, that is, the explosive is arranged in the point column ore body section to be recovered, so as to improve the breaking efficiency of the blast energy on the ore body and avoid the diffusion of the energy to the non-target area; the lower wall rock section is left empty, that is, the part of the blast hole extending to the lower wall rock after passing through the point column is kept without explosive, if the lower wall rock section is charged, part of the energy will be consumed in crushing the non-target rock, which reduces the ore breaking quality and causes overbreak, this step is based on the three-dimensional coordinates of the ore column provided in S101, by strictly restricting the blast energy to the target ore body, the blast efficiency and resource recovery rate are improved, and the stability of the stope is maintained, and the chain risk caused by the damage of the surrounding rock is avoided. The stemming is filled with inert materials (such as a mixture of clay and sand) at the junction of the explosive and the wall rock section, which blocks the escape of the explosion gas to the surrounding rock cracks by using the compressibility and sealing property of the inert materials, and at the same time, the effective working time of the explosion gas on the ore body is improved, and the uniformity of the ore breaking is enhanced.

[0077] In some embodiments, with reference to Figure 15 In S104, charging and detonating the blast hole to fall the ore, comprising: S1042, using micro-difference blasting to directionally detonate the explosive in the lateral fan-shaped medium-length hole. Specifically, the core of this technical solution is to control the release direction of the blast energy by time sequence, so as to solve the problems of blast disturbance control and ore breaking efficiency in the point column recovery process. Specifically, the micro-difference blasting controls the time interval of the detonation of the adjacent blast holes, so that the explosion stress wave forms a superposition effect in the ore body, and the blast energy is concentrated on the central area of the point column, which on the one hand promotes the point column ore body to be fully broken along the preset free surface, and on the other hand reduces the vibration influence on the surrounding rock of the goaf through the stress wave mutual cancellation mechanism, for example, the time interval of the micro-difference blasting is set to 50 milliseconds.

[0078] The surrounding rock of the steeply inclined goaf is prone to slip and collapse under the blast vibration, and the micro-difference blasting decomposes the total blast energy into multiple small-scale energy releases, so that the main frequency of the vibration is shifted to the non-resonant frequency band, and the vibration intensity is reduced. At the same time, the energy is directionally converged to ensure that the point column is fully broken at one time, and the cumulative damage of the secondary blasting to the stability of the goaf is avoided. Thus, the point column is efficiently and low-disturbance recovered without the need for personnel to enter the goaf.

[0079] In some embodiments, with reference to Figures 1 to 5 For example, a thin ore vein segmented medium-length hole multi-directional coordinated ore falling mining method comprises the following steps:

[0080] S1, adopt three-dimensional laser detection technology to detect the mined-out area 30 formed by the shallow hole shrinkage method of steeply inclined ore body, accurately determine the three-dimensional form of the mined-out area 30 and the position, size and form of the point column 40 in the mined-out area 30.

[0081] S2, according to the specific position of the point column 40 in the mined-out area 30, the projection area in the horizontal direction is determined, and the cross-vein connecting roadway 60 is excavated to the projection position of the point column 40 in the cross-vein roadway 10.

[0082] The specification of the cross-vein connecting roadway 60 is 2m×2m-2.2m×2.2m, and the length of the cross-vein connecting roadway 60 is determined according to the position of the point column 40 in the mined-out area 30. In order to ensure the effect of rock drilling and blasting, the cross-vein connecting roadway 60 is constructed to the boundary position of the projection of the point column 40 as far as possible.

[0083] When the width of the point column 40 is large, the cross-vein rock drilling roadway 70 needs to be constructed along the ore body strike direction at the end of the cross-vein connecting roadway 60. The specification of the cross-vein rock drilling roadway 70 is 2.5m×2.5m-3.m×3m, and the length of the cross-vein rock drilling roadway 70 is determined according to the width of the point column 40. In order to better construction, the length should be greater than the width of the point column 40.

[0084] S3, in the end of the cross-vein connecting roadway 60 or the cross-vein rock drilling roadway 70, a lateral fan-shaped medium-depth hole 50 is constructed by using a medium-depth hole drilling machine to the position of the point column 40 in the mined-out area 30. The lateral fan-shaped medium-depth hole 50 should be constructed to the boundary position of the point column 40 between the ore body and the hanging wall surrounding rock. The length of the lateral fan-shaped medium-depth hole 50 is determined according to the specific position of the point column 40 in the mined-out area 30.

[0085] The hole spacing of the hole row surface line formed by the lateral fan-shaped medium-depth hole 50 in the point column 40 is 1.2m-1.4m, and the hole bottom distance of the lateral fan-shaped medium-depth hole 50 is 1.4m-1.6m.

[0086] S4, after the directional construction of the lateral fan-shaped medium-depth hole 50 is completed, the explosive is loaded into the lateral fan-shaped medium-depth hole 50, and only the ore body in the point column 40 is charged.

[0087] S5, after the charging is completed, the explosive in the lateral fan-shaped medium-depth hole 50 is plugged by using stemming to prevent the blasting capacity from leaking along the uncharged lateral fan-shaped medium-depth hole 50 during the detonation of the explosive, which affects the blasting effect.

[0088] The length of the stemming used to plug the explosive in the lateral fan-shaped medium-depth hole 50 is not less than 0.5m.

[0089] S6. The explosives in the lateral fan-shaped deep holes 50 are detonated in a directional manner using a micro-delay blasting method. The detonation sequence is to first detonate the lateral fan-shaped deep holes 50 on both sides, and then detonate the lateral fan-shaped deep holes 50 in the middle. The detonation sequence of each row of lateral fan-shaped deep holes 50 is to first detonate the middle hole, and then detonate the holes at both ends.

[0090] The detonation time interval for the explosive in the lateral fan-shaped deep hole 50 is 50ms.

[0091] S7. The point pillar 40 in the goaf 30 is collapsed by explosive blasting. The collapsed ore falls directly into the goaf 30 and falls into the bottom ore discharge funnel 20 by gravity. It is then loaded into trucks and transported out of the mining area through the ore discharge funnel 20 in the cross-vein roadway 10.

[0092] S8. Repeat steps S3-S7 sequentially according to the number of point pillars 40 in goaf 30 until all point pillars 40 in goaf 30 are recovered.

[0093] like Figure 5 As shown, in some embodiments of the present invention, four rows of lateral fan-shaped deep holes 50 are arranged, and four blast holes are arranged in each row of lateral fan-shaped deep holes 50. During blasting, the blasting sequence is as follows: first, the two middle blast holes in the first row of lateral fan-shaped deep holes 50 are detonated, followed by the two blast holes at both ends in the first row of lateral fan-shaped deep holes 50, the two middle blast holes in the fourth row of lateral fan-shaped deep holes 50, the two blast holes at both ends in the fourth row of lateral fan-shaped deep holes 50, the two middle blast holes in the second row of lateral fan-shaped deep holes 50, the two blast holes at both ends in the second row of lateral fan-shaped deep holes 50, the two middle blast holes in the third row of lateral fan-shaped deep holes 50, and the two blast holes at both ends in the third row of lateral fan-shaped deep holes 50.

[0094] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications, equivalent substitutions, and improvements made by those skilled in the art within the scope of the technology disclosed in the present invention, and within the spirit and principles of the present invention, should be covered within the scope of protection of the present invention.

[0095] It should be noted that this application is not limited to the above-described embodiments. The above embodiments are merely examples, and any embodiments with the same structure and effect as the technical concept within the scope of this application are included in the technical scope of this application. Furthermore, various modifications that can be conceived by those skilled in the art to the embodiments, and other ways of constructing by combining some of the constituent elements of the embodiments, without departing from the spirit of this application, are also included in the scope of this application.

Claims

1. A method for pillar directional blasting recovery in steeply inclined voids, characterized by, The application relates to a method for constructing a blast hole in a point pillar of a goaf formed by a shallow hole shrinkage method. The method comprises the following steps: adopting a three-dimensional laser scanning technology to perform full-section scanning on the goaf formed by the shallow hole shrinkage method, generating a point cloud model, capturing a point pillar position, size and shape of the goaf to detect three-dimensional shape parameters of the point pillar; pre-drilling a vein-passing roadway at the bottom of the ore body, and the vein-passing roadway is arranged along the bottom of the ore body; projecting the three-dimensional coordinates of the point pillar to a horizontal plane to determine the corresponding area of the point pillar in the vein-passing roadway; driving a vein-passing connecting roadway from the vein-passing roadway to the projection point to form a path connected with the point pillar in a lateral direction, and providing a physical channel for an external construction blast hole, and ensuring that the working face is isolated from the goaf; transporting a medium-deep hole drilling machine to the end of the vein-passing connecting roadway or the vein-passing roadway, accurately designing the blast hole direction and depth based on the three-dimensional shape parameters, and making the blast hole penetrate from the stable surrounding rock zone to the inside of the point pillar, so that the blast hole is constructed from the outside of the goaf to the point pillar of the goaf, and personnel are prevented from entering the goaf by external drilling; loading explosives into the blast hole and initiating the blast hole to make the point pillar break according to the preset shape, and realizing controllable caving by using the structural weakness of the point pillar; 2. The method of pillar blasting in steeply inclined stope according to claim 1, characterized in that, locating the spatial distribution of the caved ore by the three-dimensional model to provide a basis for the layout of an ore-drawing hopper, and transporting the ore out of the stope by the ore-drawing hopper in the vein-passing roadway. After the medium-deep hole drilling machine is transported to the end of the vein-passing connecting roadway or the vein-passing roadway, the blast hole is constructed from the outside of the goaf to the point pillar of the goaf, and the method further comprises the following steps:

3. The method of pillar blasting in steeply inclined stope according to claim 1, characterized in that, using the medium-deep hole drilling machine to construct a lateral fan-shaped blast hole group until the length of the blast hole reaches the junction of the ore body and the upper wall surrounding rock. In the step of driving the vein-passing connecting roadway from the vein-passing roadway to the projection point, the method further comprises the following steps:

4. The method of pillar blasting in steeply inclined, empty areas according to claim 1, characterized in that, driving the vein-passing connecting roadway to the projection boundary position of the point pillar. In the step of driving the vein-passing connecting roadway from the vein-passing roadway to the projection point, the method further comprises the following steps:

5. The method of pillar blasting in steeply inclined, empty areas according to claim 1, characterized in that, driving the vein-passing connecting roadway to the projection boundary position of the point pillar, and constructing an along-vein drill roadway to the boundary of the along-vein drill roadway which exceeds the projection width direction of the point pillar. In the step of loading explosives into the blast hole and initiating the blast hole to make the point pillar break, the method further comprises the following steps:

6. The method of pillar blasting and recovery in a steeply inclined void according to claim 5, wherein, loading explosives in the point pillar ore body section, leaving a gap in the lower wall surrounding rock section, and using stemming to block the junction of the explosives and the surrounding rock section. In the step of loading explosives into the blast hole and initiating the blast hole to make the point pillar break, the method further comprises the following steps: adopting a millisecond blasting method to initiate the explosives in the lateral fan-shaped medium-deep hole in a directional manner.

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