Conical bottom blasting one-time well completion construction method

Abstract

The invention provides a conical bottom blasting one-time well completion construction method which comprises the steps that a vertical shaft area is planned between a rock drilling roadway and a slag discharging roadway, a plurality of blast holes are formed in the vertical shaft area, and the blast holes are formed in a diffusion mode from inside to outside with the center of the vertical shaft area as the circle center; explosive charging operation is carried out in the blast holes, staged explosive charging is adopted in the blast holes, explosive distribution in each blast hole is adjusted, the explosive in the blast holes is controlled to be detonated in a staged mode in the direction from the slag discharging roadway to the rock drilling roadway, and therefore a conical area is formed at the bottoms of the blast holes in the vertical shaft area after single-section blasting in the blasting well forming process; the area of a lower section blasting free face is enlarged, the explosive blasting compensation space is enlarged, the blasting energy utilization efficiency is improved, and the influence of clamping manufacturing on the well completion effect is relieved.

Description

Technical Field

[0001] The present application relates to the technical field of mining blasting, and in particular to a one-time well construction method using cone-shaped bottom blasting. Background Art

[0002] Single-shot well completion blasting technology offers advantages such as high efficiency, low cost, and strong adaptability. It can significantly shorten construction cycles and reduce overall costs, thus possessing strong potential for engineering applications. However, due to the limited space during vertical shaft construction, resulting in a small free surface area and a significant rock mass clamping effect, blasting results are often unsatisfactory. This can easily lead to problems such as irregular well formation and blasting failure due to the small rock mass spacing and compression. Summary of the Invention

[0003] In view of the technical problems existing in the background technology, the present application provides a one-time well construction method of cone-shaped bottom blasting to achieve high efficiency, safety and good forming quality of wellbore blasting construction.

[0004] The present application provides a method for single-step well construction by cone-shaped bottom blasting, the specific steps of which include: A vertical shaft area is planned between the rock drilling roadway and the slag discharge roadway, and a plurality of blastholes are arranged in the vertical shaft area, and the plurality of blastholes are arranged in a diffuse pattern from the inside to the outside with the center of the vertical shaft area as the center of the circle; Charging operations are carried out in the blastholes. The blastholes are charged in stages, and the distribution of explosives in each blasthole is adjusted to control the explosives in the blastholes to be detonated in stages from the slag discharge tunnel toward the rock drilling tunnel. After each stage of detonation, a conical blasting surface is formed on the side of the vertical shaft area facing the slag discharge tunnel.

[0005] Furthermore, in this embodiment, the blasthole adopts staged charging including a first blasting stage, a subsequent blasting stage and a final blasting stage; in: In the first blasting stage, the charge height in the blastholes in the vertical shaft area decreases sequentially from the inside to the outside of the vertical shaft area. When the explosives in the blastholes are detonated, a conical blasting surface is formed on the side of the vertical shaft area facing the slag discharge roadway. In the subsequent blasting stage, the charge heights in the blast holes in the shaft area are the same; During the final blasting stage, explosives are loaded into the remaining blast holes.

[0006] Furthermore, in this embodiment, the blast hole includes a central groove hole, an expansion groove hole and a peripheral forming hole. The central groove hole is arranged at the center of the vertical shaft area, the peripheral forming hole is arranged at the edge of the vertical shaft area, and the expansion groove hole is located between the central groove hole and the peripheral forming hole.

[0007] Furthermore, in this embodiment, auxiliary holes are also included. The auxiliary holes are arranged in the vertical shaft area. The auxiliary holes and the cavity expansion holes are arranged in a square hole pattern. The cavity expansion holes are located at the midpoints of the four sides of the square, and the auxiliary holes are located at the four corners of the square.

[0008] Furthermore, in this embodiment, the diameter of the auxiliary hole is larger than the diameter of the cavity expansion hole.

[0009] Furthermore, in this embodiment, the peripheral forming hole is located on the extension line of the center of the central groove hole and the cavity expansion groove hole or the auxiliary hole.

[0010] Furthermore, in this embodiment, in the process of controlling the explosives in the blasthole to be detonated in stages from the slag discharge tunnel toward the rock drilling tunnel, the detonation order of the blasthole in each stage is the central slot hole, the expanded cavity slot hole and the peripheral forming hole.

[0011] Furthermore, in this embodiment, the blasthole adopts staged charging including: a first blasting stage, a subsequent blasting stage and a final blasting stage; in: In the first blasting stage, the charge height in the blastholes in the vertical shaft area decreases sequentially from the inside to the outside of the vertical shaft area. When the explosives in the blastholes are detonated, a conical blasting surface is formed on the side of the vertical shaft area facing the slag discharge roadway. In the subsequent blasting stage, the charge heights in the blast holes in the shaft area are the same; In the final blasting stage, the remaining blast holes are filled with explosives.

[0012] Furthermore, in this embodiment, the diameter of the central cutout hole is larger than the diameter of the expanded cavity cutout hole.

[0013] Furthermore, in this embodiment, the blasthole is filled with emulsion explosive or mixed explosive.

[0014] Furthermore, in this embodiment, after the blastholes are filled with explosives, they are blocked in sequence by filling with mud and sand and blocking blocks.

[0015] Beneficial effect: The present application provides a method for one-time well construction by cone-shaped bottom blasting. According to the established vertical shaft construction plan, a vertical shaft area is planned between the rock drilling tunnel and the slag discharge tunnel, and the blasthole construction position for blasting is planned in the vertical shaft area. The rock drilling equipment is used to start the downward drilling construction in the upper rock drilling tunnel, and then the blasthole is opened between the rock drilling tunnel and the slag discharge tunnel. A plurality of blastholes are arranged in the vertical shaft area, wherein a central blasthole is provided in the center of the vertical shaft area, and the remaining blastholes are arranged around the central blasthole. The core is diffusely arranged from the inside to the outside in the vertical shaft area. After the drilling work of the blasthole between the rock drilling tunnel and the slag discharge tunnel is completed, the blasthole is filled with explosives. The explosives in the blasthole are charged in stages, and the distribution of explosives in each blasthole is adjusted during the charging process, so that the blastholes in the vertical shaft area form a cone-shaped area at the bottom after a single-stage blasting during the blasting well formation process, thereby expanding the area of the free surface of the lower blasting, increasing the blasting compensation space of the explosives, improving the utilization efficiency of the blasting energy, and reducing the influence of the clamping effect on the well formation effect.

[0016] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, 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 application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] To more clearly illustrate the technical solution of this application, the following is a brief introduction to the drawings used in this application. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be derived from these drawings without inventive effort.

[0018] Figure 1 A diagram of a conical bottom blasting well construction structure is provided for the embodiment of the present application; Figure 2 A blasthole distribution diagram is provided for the embodiments of this application.

[0019] Description of reference numerals: 10. Rock drilling tunnel; 20. Slag discharge tunnel; 30. Bomb hole; 310, center slot hole; 320, cavity expansion slot hole; 330, peripheral forming hole; 340, auxiliary hole; 40. Explosives. DETAILED DESCRIPTION

[0020] The following embodiments of the technical solution of the present application 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 application and are therefore only examples and are not intended to limit the scope of protection of the present application.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled 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 this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned figure descriptions are intended to cover non-exclusive inclusions.

[0022] In the description of the embodiments of this application, the technical terms "first" and "second" are used only to distinguish different objects and should not be understood to indicate or imply relative importance or implicitly specify the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise clearly and specifically defined.

[0023] References to "embodiments" herein 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 application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent 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.

[0024] In the description of the embodiments of this application, 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 exist simultaneously, and B exists alone. In addition, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0025] In the description of the embodiments of the present application, 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).

[0026] In the description of the embodiments of the present application, 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 application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0027] In the description of the embodiments of the present application, unless otherwise expressly specified or limited, technical terms such as "installed," "connected," "connected," 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; internal connections between two components or interactions between two components. Those skilled in the art can understand the specific meanings of the above terms in the embodiments of the present application based on specific circumstances.

[0028] In underground mining, vertical shafts are a core component of the entire mine construction and production lifecycle. Currently, most mines in my country still primarily utilize traditional tunneling methods or raise boring for vertical shaft construction. However, these methods are generally associated with long construction cycles, high operating costs, and significant safety risks.

[0029] In comparison, single-shot well blasting technology offers advantages such as high efficiency, low cost, and strong adaptability. It can significantly shorten construction periods and reduce overall costs, thus possessing strong potential for engineering applications. However, due to the limited space during vertical shaft construction, resulting in a small free surface area and a significant clamping effect between rock masses, blasting results are often unsatisfactory, and are prone to problems such as irregular well formation and blasting failure due to the small space between rocks.

[0030] In order to solve the problems of limited space during shaft construction, resulting in a small free surface area, significant clamping effect between rock masses, often unsatisfactory blasting effect, irregular well formation, small rock space and mutual squeezing leading to blasting failure, etc., the present application provides a one-time well formation construction method by cone-shaped bottom blasting, which adopts concentric circle uniform arrangement to set blast holes, and combines reasonable detonation sequence and charging parameter design to control the wellbore contour and regular formation during the blasting process, significantly improve the overall forming quality and flatness of the well wall, and reduce the subsequent finishing workload, so as to achieve high efficiency, safety and good forming quality of wellbore blasting construction.

[0031] Please refer to Figure 1 , Figure 1A construction diagram of a conical bottom blasting well is provided for the embodiment of the present application. The specific steps include: A vertical shaft area is planned between the rock drilling tunnel 10 and the slag discharge tunnel 20, and a plurality of blastholes 30 are set in the vertical shaft area, and the plurality of blastholes are diffusely arranged from the inside to the outside with the center of the vertical shaft area as the center of the circle; charging operations are carried out in the blastholes, and the blastholes are charged in stages, and the distribution of explosives 40 in each blasthole is adjusted. The explosives 40 in the blastholes are controlled to be detonated in stages from the slag discharge tunnel 20 toward the rock drilling tunnel 10, and after each stage of detonation, a conical blasting surface is formed on the side of the vertical shaft area facing the slag discharge tunnel 20.

[0032] Specifically, in this embodiment, a vertical shaft construction plan is formulated, and a vertical shaft area is planned between the rock drilling tunnel 10 and the slag discharge tunnel 20 according to the formulated vertical shaft construction plan, and blasthole construction positions for blasting are planned in the vertical shaft area. Rock drilling equipment is used to start downward drilling construction in the upper rock drilling tunnel 10, and then blastholes are opened between the rock drilling tunnel 10 and the slag discharge tunnel 20. A plurality of blastholes are set in the vertical shaft area, wherein a central blasthole is set in the center of the vertical shaft area, and the remaining blastholes are arranged from the inside out with the central blasthole as the center. It is diffusely arranged in the vertical shaft area. After the blastholes between the rock drilling tunnel 10 and the slag discharge tunnel 20 are opened, the explosives 40 are filled into the blastholes. The explosives 40 in the blastholes are charged in stages, and the distribution of the explosives 40 in each blasthole is adjusted during the charging process, so that the blastholes in the vertical shaft area form a conical area at the bottom after a single-stage blasting during the blasting well formation process, thereby expanding the area of the free surface of the lower blasting, increasing the blasting compensation space of the explosives 40, improving the efficiency of blasting energy utilization, and reducing the influence of the clamping effect on the well formation effect.

[0033] The present invention provides a method for well construction by one-step cone bottom blasting, which includes the following steps: S1. A vertical shaft area is planned between the rock drilling tunnel 10 and the slag discharge tunnel 20. A plurality of blastholes are set in the vertical shaft area, and the plurality of blastholes are diffusely arranged from the inside to the outside with the center of the vertical shaft area as the center of the circle.

[0034] In this embodiment, if Figure 2 As shown, the blasthole includes a central groove hole 310, an expansion groove hole 320 and a peripheral forming hole 330, wherein the central groove hole 310 is arranged at the center of the vertical shaft area, the peripheral forming hole 330 is arranged at the edge of the vertical shaft area, and the expansion groove hole 320 is located between the central groove hole 310 and the peripheral forming hole 330.

[0035] Specifically, the center slot hole 310 is located in the center of the shaft area and is used to first create an initial, relatively small free surface or cavity inside the hard rock. During the blasting process, the center slot hole 310 is detonated first, and the explosive energy is used to crush and throw the rock in the center to form a "slot hole", which provides a crucial new free surface for the subsequent blasting of the blasthole, making the rock more likely to break under tensile stress.

[0036] The cavity expansion slot hole 320 is located immediately around the central slot hole 310 and is used to further expand the volume and range of the slot area based on the initial free surface created by the central slot hole 310 to form a larger cavity. During the blasting process, after the central slot hole 310 is detonated (usually the next extended period, such as MS3), the cavity expansion slot hole 320 is detonated using the newly formed free surface. The explosive energy further crushes the rock around the central slot hole 310 and throws it into the central cavity, significantly expanding the size of the slot area.

[0037] Peripheral forming holes 330, located at the outermost edge of the shaft area, closely follow the designed excavation contour of the shaft area. They are used to precisely form the required excavation contour, minimize damage to the retained rock mass (overbreak or underbreak), and maintain surrounding rock stability and surface smoothness. During the blasting process, peripheral forming holes 330 are detonated last, using a lower charge density (small-diameter cartridges, air-spaced charges) and a closer spacing between holes. After the central cutout hole 310 and the expansion cutout hole 320 are blasted, the peripheral forming holes 330 are detonated simultaneously or with slight delays, creating through-hole fractures between the holes and smoothly fracturing the rock along the contour.

[0038] In some embodiments, an auxiliary hole 340 is further provided in the vertical shaft area. The auxiliary hole 340 is arranged between the central groove hole 310 and the peripheral forming hole 330, and is staggered with the expansion cavity groove hole 320. In this embodiment, the auxiliary hole 340 is not charged with explosives and is used to increase the free surface of the groove hole blasting.

[0039] For example, in this embodiment, the central cut hole 310 is located in the center of the vertical shaft area, and the auxiliary holes 340 and the expanded cavity cut holes 320 are arranged in a square pattern. The expanded cavity cut holes 320 are located at the midpoints of the four sides of the square, and the auxiliary holes 340 are located at the four corners of the square. When the expanded cavity cut holes 320 are detonated, they blast toward the cavity created by the central hole (the line of least resistance points to the center). The auxiliary holes 340 located at the four corners of the square provide additional, closer free surfaces, which significantly reduces the rock's clamping force on the expanded cavity cut holes 320 in the corner direction. Secondly, the auxiliary holes 340 located at the four corners of the square cause stress waves to reflect and concentrate around them, which helps to crack or break the rock at the auxiliary holes 340 and further "soften" the boundaries of the cut area.

[0040] In some embodiments, the peripheral forming hole 330 is located on the extension line of the center of the central groove hole 310 and the expanded cavity groove hole 320 or the auxiliary hole 340. In this embodiment, the extension line layout ensures that the minimum resistance line of each peripheral hole points to the formed groove cavity, so that the blasting energy is released along the path of least resistance, avoiding energy dispersion, thereby ensuring maximum energy utilization.

[0041] S2. Fill the blastholes with explosives 40. The explosives 40 in the blastholes are charged in stages, and the distribution of the explosives 40 in each blasthole is adjusted during the charging process, so that the blastholes in the vertical shaft area form a cone-shaped area at the bottom after a single-stage blasting during the blasting well formation process.

[0042] In this embodiment, the blasting process of the blasthole is mainly divided into three stages, namely the first blasting stage, the subsequent blasting stage and the final blasting stage.

[0043] S21. The first blasting stage: The first blasting stage is mainly used to form a cone-shaped area in the shaft area.

[0044] When the explosives 40 are filled into the blasthole during the first blasting phase, the charge heights in the central cutout hole 310 , the expanded cavity cutout hole 320 and the peripheral formed hole 330 are reduced in sequence.

[0045] The charge height in the central cut hole 310 is the highest, so the explosives 40 in the central cut hole 310 generate a strong shock wave after explosion, which preferentially breaks the rock downward to form a cone tip.

[0046] The charge height in the expanded cavity cutout hole 320 is reduced compared to the central cutout hole 310 . After the explosive 40 in the expanded cavity cutout hole 320 explodes, the energy of the explosive 40 diffuses laterally to form a cone.

[0047] The charge height in the peripheral forming hole 330 is further reduced compared to the cavity expansion and grooving hole 320 . After the explosive 40 in the peripheral forming hole 330 explodes, the weak explosive force initially trims the contour to avoid damaging the surrounding rock.

[0048] S22, subsequent blasting stage, the subsequent blasting stage is used to deepen the vertical wellbore.

[0049] In the subsequent blasting stage, the height of the explosives in the central slot hole 310, the expanded cavity slot hole 320 and the peripheral forming hole 330 approaches the same, so in the subsequent blasting stage, the depth of the shaft is further extended, and the blasting surface at the bottom of the shaft is kept in a conical structure during the shaft extension process.

[0050] S23, the final blasting stage, in the final blasting stage, the full filling and one-time blasting and slag removal method is adopted to achieve the final shaft forming. It can be understood that in the final blasting stage, will.

[0051] In some embodiments, during the controlled detonation of explosives 40 in blastholes from the slag discharge tunnel 20 toward the rock drilling tunnel 10, the detonation order for each blasthole is the central cutout hole 310, the expanded cavity cutout hole 320, and the peripheral formed hole 330, achieving efficient blasting through mechanical relay and energy synergy. It is understood that the central cutout hole 310 is the first to be detonated, forcibly tearing the homogeneous rock mass, creating initial compensation space and generating a radial fracture network, providing an energy transfer channel for subsequent blasting. The expanded cavity cutout hole 320 then takes over, using the radial fractures generated by the central hole as a pre-crack surface to preferentially crush the rock along the fracture direction. The peripheral formed hole 330 is then detonated to form a complete free surface.

[0052] In some embodiments, the detonation interval between the central slot hole 310, the expanded cavity slot hole 320 and the peripheral forming hole 330 is 25ms. By controlling the detonation delay between the central slot hole 310, the expanded cavity slot hole 320 and the peripheral forming hole 330, directional energy transfer is achieved.

[0053] Specifically, when the blasting of the central cut hole 310 transitions to the blasting of the expanded cavity cut hole 320 , the detonation interval between the central cut hole 310 and the expanded cavity cut hole 320 is 25ms, waiting for the gas pressure generated by the explosion of the central cut hole 310 to reach the peak value, so as to fully utilize the gas expansion energy.

[0054] When the blasting of the cavity expansion slot hole 320 transitions to the blasting of the peripheral forming hole 330 , the detonation interval between the central slot hole 310 and the cavity expansion slot hole 320 is 25ms to meet the rock throwing time.

[0055] In some embodiments, the aperture of the auxiliary hole 340 is larger than the aperture of the expansion cavity groove hole 320. For example, in this embodiment, the auxiliary hole 340 with a large aperture is used to generate a stronger reflected tensile stress concentration under the action of the explosion stress wave, thereby improving the blasting effect.

[0056] In some embodiments, the aperture of the central slot hole 310 is larger than the aperture of the expanded cavity slot hole 320. It can be understood that in this embodiment, the amount of explosives per unit height in the central slot hole 310 is higher than the amount of explosives per unit height in the expanded cavity slot hole 320. Under the same charging height, more explosives 40 can be loaded in the central slot hole 310, so that after blasting, the central slot hole 310 can generate a strong shock wave, forcibly tearing the homogeneous rock mass to create an initial compensation space.

[0057] In some embodiments, the blasthole is filled with emulsion explosive 40 or mixed explosive 40. Both emulsion explosive 40 and mixed explosive 40 have good explosive performance, which can produce a strong impact and crushing effect on the rock, reduce explosion rejection and residual explosion, and improve blasting safety, reliability and efficiency.

[0058] In some embodiments, after the blasthole is filled with explosives 40, it is sealed in turn by filling with mud and sand and sealing blocks. The sealing body forms a physical barrier, forcing the high-temperature and high-pressure gas and shock wave generated by the explosion of the explosives 40 to act in a directionally directed manner on the rock of the hole wall, reducing the energy dissipation from the hole mouth, thereby enhancing the rock crushing effect and improving the blasting fragmentation.

[0059] Please also refer to Figure 1-2 The cone blasting one-time well construction method provided in the embodiment of the present application specifically includes: Downward drilling construction was started in the upper drilling tunnel 10 using rock drilling equipment. First, a central slot hole 310 with a diameter of 90 mm was drilled at the center of the vertical shaft projection surface. Subsequently, the cavity expansion slot holes 320 and the auxiliary holes 340 were arranged in a square hole arrangement. The diameter of the cavity expansion slot hole 320 was 60 mm and it was arranged at the midpoint of the four sides of the square. The hole spacing between the central slot hole 310 and the cavity expansion slot hole 320 was 350 mm. The diameter of the auxiliary holes 340 was 90 mm and they were arranged at the four vertices of the square. The peripheral forming holes 330 were arranged according to the extension line of the connection line between the central slot hole 310 and the cavity expansion hole and the auxiliary holes 340. The diameter of the eight forming holes was 60 mm and they were evenly arranged on the periphery of the central slot hole 310, with a distance of 800 mm from the central slot hole 310.

[0060] Before charging, the sealing block 3 needs to be installed. A long anti-electric rope is used, with one end left on the rock drilling tunnel 10 for fixation, and the other end is sent from the top of the blasthole to the safe area outside the bottom slag discharge tunnel 20 according to the required blasthole sealing requirements. Then, the top handle of the sealing block is tied tightly. Because the base size of the sealing block is larger than the aperture of the blasthole, it is pulled and re-fixed on one end of the rock drilling tunnel 10 so that the sealing block fits the bottom of the hole and a small amount of mud and sand is added to ensure uniform bottom sealing.

[0061] The blasting construction adopts staged charging. Except for the auxiliary hole 340 used to increase the free surface, all other types of holes are involved in the charging.

[0062] In the first blast, explosives 40 were loaded into the central cutout 310, the expanded cavity cutout 320, and the peripheral forming holes 330. To ensure a tapered structure at the shaft bottom after blasting, the charge height ratios were 1:0.65:0.15, and the charge volume ratios were 1:0.29:0.07. Subsequent blasts employed charge height ratios of 1:0.97:0.97, and charge volume ratios of 1:0.43:0.43. The final charge, to achieve the specified shaft height and shape, employed a charge height ratio of 1:1.29:1.74, and a charge volume ratio of 1:0.57:0.77. The remaining portion was blasted and slag removed in a single blast, achieving the final shaft formation.

[0063] Detonation is controlled by electronic digital detonators, with detonation initiated at the hole mouth. Detonations are performed sequentially, following the central cutout 310, the expanded cavity cutout 320, and the peripheral formed holes 330. The detonation time difference is set to 25 ms to ensure orderly energy transfer and control the directional rock fragmentation effect.

[0064] The method described in this invention is simple to construct, requires minimal equipment, and is reliable, effectively reducing construction time and costs. A company using this method to excavate a 14-meter vertical shaft reduced the original construction period from 20 days to just four. This effectively shortened the construction period and achieved superior results compared to traditional shaft excavation methods.

[0065] It should be noted that the present application 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 present application are all included in the technical scope of the present application. In addition, without departing from the scope of the present application, any 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 application.

Claims

1. A method for well construction by one-step cone bottom blasting, characterized in that: The specific steps include: A vertical shaft area is planned between the rock drilling roadway and the slag discharge roadway, and a plurality of blastholes are arranged in the vertical shaft area, and the plurality of blastholes are arranged in a diffuse pattern from the inside to the outside with the center of the vertical shaft area as the center of the circle; Charging operations are carried out in the blastholes. The blastholes are charged in stages, and the distribution of explosives in each blasthole is adjusted to control the explosives in the blastholes to be detonated in stages from the slag discharge tunnel toward the rock drilling tunnel. After each stage of detonation, a conical blasting surface is formed on the side of the vertical shaft area facing the slag discharge tunnel.

2. The method for one-step well construction by cone-shaped bottom blasting according to claim 1, characterized in that: The blasthole is charged in stages, including the first blasting stage, the subsequent blasting stage and the final blasting stage; in: In the first blasting stage, the charge height in the blastholes in the vertical shaft area decreases sequentially from the inside to the outside of the vertical shaft area. When the explosives in the blastholes are detonated, a conical blasting surface is formed on the side of the vertical shaft area facing the slag discharge roadway. In the subsequent blasting stage, the charge heights in the blast holes in the shaft area are the same; During the final blasting stage, explosives are loaded into the remaining blast holes.

3. The method for one-step well construction by cone-shaped bottom blasting according to claim 1, characterized in that: The blasthole includes a central slot hole, an expansion slot hole and a peripheral forming hole. The central slot hole is arranged at the center of the shaft area, the peripheral forming hole is arranged at the edge of the shaft area, and the expansion slot hole is located between the central slot hole and the peripheral forming hole.

4. The method for one-step well construction by cone-shaped bottom blasting according to claim 3, characterized in that: It also includes auxiliary holes, which are arranged in the vertical shaft area. The auxiliary holes and the cavity expansion and groove holes are arranged in a square pattern. The cavity expansion and groove holes are located at the midpoints of the four sides of the square, and the auxiliary holes are located at the four corners of the square.

5. The method for one-step well construction by cone-shaped bottom blasting according to claim 4, characterized in that: The aperture of the auxiliary hole is larger than the aperture of the cavity expansion hole.

6. The method for one-step well construction by cone-shaped bottom blasting according to claim 4, characterized in that: The peripheral forming hole is located on the extension line of the center of the central groove hole and the cavity expansion groove hole or the auxiliary hole.

7. The method for one-step well construction by cone-shaped bottom blasting according to claim 3, characterized in that: In the process of controlling the explosives in the blastholes to be detonated in stages from the slag discharge tunnel to the rock drilling tunnel, the detonation order of the blastholes in each stage is the central slot hole, the cavity expansion slot hole and the peripheral forming hole.

8. The method for one-step well construction by cone-shaped bottom blasting according to claim 3, characterized in that: The diameter of the central cutout hole is larger than the diameter of the expanded cavity cutout hole.

9. The method for one-step well construction by cone-shaped bottom blasting according to claim 1, characterized in that: The blasthole is filled with emulsion explosive or mixed explosive.

10. The method for one-step well construction by cone-shaped bottom blasting according to claim 1, characterized in that: After the blastholes are filled with explosives, they are blocked in sequence by filling with mud and sand and blocking blocks.

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