Digging method for underground large-section geological drilling chamber

Abstract

The invention discloses a digging method for an underground large-section geological drilling chamber. The digging method comprises the following steps: (1) determining the size of the geological chamber and the length of a connection way; (2) firstly, determining the construction position of a geological chamber, vertically tunneling a connection way to the center of the chamber in a roadway closest to the chamber, and expanding and brushing according to the specification and size of the chamber until the plane size of the chamber is met; (3) carrying out top-lifting blasting upwards according to the size of the chamber to form a bottom chamber, and controlling the height to be 5m; (4) a measure connection slope ramp is tunneled at a roadway setting position, the gradient is controlled, and a place with a specified height from a floor is designed to be communicated with the top of the chamber; (5) after tunneling to the top of the chamber, excavating the top chamber according to the three-star arch technical standard to form the overall dimension of the top chamber, and controlling the height of the top of the chamber to be 5m; and (6) reinforcing and supporting the 5m chamber at the top by adopting a shotcrete anchor net, controlling the shotcrete anchor thickness, and ensuring the safety of personnel and equipment during drilling.

Description

Technical Field

[0001] This invention belongs to the field of mine chamber excavation technology, specifically relating to a method for excavating large-section geological drilling chambers underground. Background Technology

[0002] This invention mainly addresses the problem in underground mines where, during geological exploration, drilling ultra-deep geological boreholes (≥2000m) requires the excavation of large-section geological chambers to effectively house the drill rig due to its excessive height. However, the excavation of large-section underground chambers presents significant construction difficulties and substantial safety risks.

[0003] In the process of mineral resource exploration, geological drilling is essential. By analyzing and testing the core samples from these boreholes, physicochemical information and composition of the ore are collected, thereby determining the type, composition, grade, and other physicochemical properties of the ore in the exploration area. Drilling is usually carried out at the surface, which is convenient, quick, and simple to operate. However, when surface drilling conditions are not suitable, or when an old mine has been mined to a deep level and further exploration is needed, it is necessary to excavate and drill geological chambers underground. The deeper the borehole, the larger the required chamber size. When the borehole depth exceeds 2000m, the drill rig height generally exceeds 14m. Therefore, the minimum dimensions of the drill rig chamber must be 10*9*15 (length*width*height). When the height of an underground chamber exceeds 15 meters, current mining technology typically employs traditional muck-raising methods, using shallow stripping to gradually increase the height. However, this method poses a significant safety risk because the safety passage can become blocked by rock debris at a certain depth. Another approach is to manually excavate a raised shaft to a height of 15 meters, then gradually expand and excavate the top of the chamber until the overall chamber outline is formed. This is followed by manual excavation and expansion layer by layer downwards. This method is also labor-intensive, inefficient, and carries high safety risks, making construction extremely difficult. Therefore, when constructing deep underground chambers, both methods are not only challenging but also pose significant safety risks.

[0004] This invention employs a layered construction technique, which solves the technical problems existing in traditional chamber excavation methods. It is easy to construct, simple to operate, and highly safe, thus effectively addressing the technical challenges in traditional geological chamber construction. Summary of the Invention

[0005] This invention provides a large-section geological drilling chamber for underground drilling, which solves the technical problems existing in traditional chamber excavation methods. It is easy to construct, simple to operate, and highly safe, thus effectively solving the technical problems existing in the construction of traditional geological chambers.

[0006] Therefore, the present invention adopts the following technical solution: A method for excavating large-section geological drilling chambers in underground wells includes the following steps: (1) Determine the dimensions of the geological chamber and the length of the connecting tunnel; (2) Determine the construction location of the geological chamber, and excavate the connecting roadway vertically from the nearest roadway to the center of the chamber. Expand and slab according to the specifications and dimensions of the chamber until the plan dimensions of the chamber are met. (3) Then, according to the dimensions of the chamber, the top is blasted upwards to form the bottom chamber, with the height controlled to one-third of the total height of the chamber; (4) Set up a connecting ramp at the location of the tunnel, control the slope, and design it to connect with the top of the chamber at a specified height above the floor; (5) After the tunneling reaches the top of the chamber, the top chamber is excavated according to the three-star arch technical standard to form the outline size of the top chamber. The height of the top of the chamber is also controlled to one-third of the total height of the chamber. (6) The top chamber is reinforced with shotcrete and anchor mesh, and the thickness of the shotcrete and anchor mesh is controlled to ensure the safety of personnel and equipment during drilling; (7) After the bottom one-third and top one-third of the chamber are excavated according to the dimensions, the remaining one-third of the middle part of the chamber is solid. The remaining one-third of the middle part of the solid rock is blasted by micro-differential blasting to form the final chamber outline in one well. The surrounding holes are blasted by smooth blasting with multiple holes and less explosives. (8) After the middle third of the solid is blasted, the slag is not cleaned up. Instead, the middle third of the rock wall is supported by spraying anchor mesh on the slag using the slag climbing method and connected to the top support as a whole. After the support is completed, the remaining slag is cleaned up. (9) Finally, the bottom third of the chamber is supported by shotcrete and anchor mesh, and it must be closely connected with the support mesh of the middle wall to form a whole and improve the support strength. (10) Finally, clean up the remaining slag at the bottom of the chamber and level the floor. Harden the floor with cement to form the geological drilling working chamber.

[0007] The control principle of the excavation method of this invention is as follows: 1. Strictly follow the design for measurement and layout, and ensure construction accuracy to guarantee that the upper and lower parts of the chamber are on the same vertical plane.

[0008] 2. During the operation, it is essential to ensure that the height of the upper, middle, and lower chambers is approximately 5m to ensure that the cross-sectional dimensions of the chambers are under control.

[0009] 3. During the construction of the chamber, the surrounding holes must adopt the smooth blasting technique of drilling multiple holes and using less explosives to ensure that the outline of the chamber is smooth and to minimize the blasting vibration damage to the surrounding rock, thus creating favorable conditions for the safety of subsequent construction.

[0010] 4. When blasting in the middle 5m, the hole network parameters should be scientifically designed according to the lithology and the construction should be carried out according to the design parameters. The charge quantity should be accurately calculated. On the premise of ensuring the blasting quality, the damage to the rock wall of the chamber caused by the blasting of the surrounding holes should be reduced.

[0011] 5. Strictly follow the design of shotcrete and anchor mesh support for support, and do a good job in the acceptance and management of concealed works to ensure the quality of the chamber support.

[0012] The innovation of this invention lies in: 1. Three-section underground chamber excavation technology. Due to the extreme difficulty in constructing large-section underground chambers, this invention divides the chamber excavation into three sections: upper, middle, and lower, each with a thickness of 5m (this method can be used for excavating even taller geological chambers, with similar methods). The overall design concept simplifies the operation process and improves construction efficiency.

[0013] 2. Traditionally, underground geological chamber excavation is carried out by manually excavating the ceiling, raising it layer by layer from bottom to top. After excavating to the designed top height of the chamber, the chamber is expanded and scoured from the top to finally form the top outline of the chamber. All operations are completed manually.

[0014] This invention changes traditional thinking by using mechanical equipment instead of manual excavation. The excavation first reaches the top of the chamber, then the top 5 meters are excavated to form the top outline. This solves the technical difficulties of traditional manual excavation methods for chambers, making construction easier, simpler to operate, and safer, thus effectively addressing the problems existing in traditional chamber construction.

[0015] 3. By using a small-section connecting tunnel to excavate to the top of the chamber, and first supporting the top 5m before excavating the chamber layer by layer downwards, the construction at the top is more convenient than traditional construction techniques, ensuring construction safety and quality, and eliminating the risks of traditional chamber construction.

[0016] 4. The 5m excavation in the middle section adopts micro-differential blasting technology to form a single blast. Because it has two free surfaces, the blasting effect is guaranteed, which reduces the difficulty of the chamber construction and improves the efficiency of the chamber construction.

[0017] 5. It simplified the construction operation method, realized mechanization to replace manpower, improved the level of mechanized operation in underground chamber excavation, and ensured the inherent safety of underground chamber excavation.

[0018] The beneficial effects of this invention are as follows: This invention features a simple process and employs a three-stage excavation technique, which changes the traditional approach to underground chamber construction, improves mechanization, and replaces manual labor with mechanized operations. This significantly reduces the risks associated with manual labor, resulting in highly efficient and rapid operations. It completely solves the technical difficulties and safety risks inherent in the construction of traditional large-section geological chambers underground, ensuring the safety of construction personnel and improving the inherent safety of underground geological chamber excavation. After widespread application, it provides a solution to the high difficulty and safety risks associated with excavating large underground chambers (over 10m in height and over 8m in length and width). Attached Figure Description

[0019] Figure 1 This is a plan of the geological drilling chamber; Figure 2 It is the construction design of the tunnel. Figure 1 ; Figure 3 It is the construction design of the tunnel. Figure 2 ; Figure 4 It is the construction design of the tunnel. Figure 3 . Detailed Implementation

[0020] The present invention will be further described below with reference to the accompanying drawings and specific embodiments: like Figures 1-4 As shown, a method for excavating large-section geological drilling chambers in underground wells includes the following specific steps: (1) Dimensions of the geological chamber: 10*9*15m (length*width*height), connecting passage length 22m, see Figure 1 .

[0021] (2) First, determine the construction location of the geological chamber. Then, excavate the connecting roadway vertically from the nearest roadway to the center of the chamber and expand it according to the specifications and dimensions of the chamber until the dimensions of the chamber are met.

[0022] (3) Then, according to the dimensions of the chamber, perform upward blasting to form the bottom chamber, with the height controlled to 5m. See Figure 2 .

[0023] (4) A connecting ramp with a slope of 12.5° was excavated at an appropriate location in the roadway, designed to connect with the top of the chamber at a height of 10m above the floor. See Appendix. Figure 3 .

[0024] (5) After the excavation reaches the top of the chamber, the top chamber will be excavated according to the three-star arch technical standard to form the outline dimensions of the top chamber. The height of the top of the chamber will also be controlled to 5m. See Figure 3 .

[0025] (6) The top 5m chamber is reinforced with shotcrete and anchor netting with a thickness of 150mm to ensure the safety of personnel and equipment during drilling.

[0026] (7) After the bottom 5m and top 5m of the chamber have been excavated according to the dimensions, the remaining 5m of solid rock in the middle of the chamber is the key part of the excavation. Micro-delay blasting is used on the remaining 5m of solid rock in the middle to form the final chamber outline in one operation. The surrounding holes are blasted using a smooth blasting technique with multiple holes and less explosive charge. See [link to relevant documentation]. Figure 4 .

[0027] (8) After the blasting of the central 5m solid, do not clean up the slag. Use the slag climbing method to support the central 5m rock wall with shotcrete and anchor mesh, and connect it with the top support as a whole. After the support is completed, clean up the remaining slag.

[0028] (9) Finally, the bottom 5m chamber is supported by shotcrete and anchor mesh, and it must be closely connected with the support mesh of the middle wall to form a whole and improve the support strength.

[0029] (10) Finally, clean up the remaining slag at the bottom of the chamber and level the floor. Harden the floor with cement to form the geological drilling working chamber.

Claims

1. A method for excavating large-section geological drilling chambers in underground mines, characterized in that, Includes the following steps: (1) Determine the dimensions of the geological chamber and the length of the connecting tunnel; (2) Determine the construction location of the geological chamber, and excavate the connecting roadway vertically from the nearest roadway to the center of the chamber. Expand and slab according to the specifications and dimensions of the chamber until the plan dimensions of the chamber are met. (3) Then, according to the dimensions of the chamber, the top is blasted upwards to form the bottom chamber, with the height controlled to one-third of the total height of the chamber; (4) Set up a connecting ramp at the location of the tunnel, control the slope, and design it to connect with the top of the chamber at a specified height above the floor; (5) After the tunneling reaches the top of the chamber, the top chamber is excavated according to the three-star arch technical standard to form the outline size of the top chamber. The height of the top of the chamber is also controlled to one-third of the total height of the chamber. (6) The top chamber is reinforced with shotcrete and anchor mesh, and the thickness of the shotcrete and anchor mesh is controlled to ensure the safety of personnel and equipment during drilling; (7) After the bottom one-third and top one-third of the chamber are excavated according to the dimensions, the remaining one-third of the middle part of the chamber is solid. The remaining one-third of the middle part of the solid rock is blasted by micro-differential blasting to form the final chamber outline in one well. The surrounding holes are blasted by smooth blasting with multiple holes and less explosives. (8) After the middle third of the solid is blasted, the slag is not cleaned up. Instead, the middle third of the rock wall is supported by spraying anchor mesh on the slag using the slag climbing method and connected to the top support as a whole. After the support is completed, the remaining slag is cleaned up. (9) Finally, the bottom third of the chamber is supported by shotcrete and anchor mesh, and it must be closely connected with the support mesh of the middle wall to form a whole and improve the support strength. (10) Finally, clean up the remaining slag at the bottom of the chamber and level the floor. Harden the floor with cement to form the geological drilling working chamber.

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