Grouting pressure feeding method and mine shaft construction method applying same

Abstract

The invention discloses a grouting pressure feeding method and a mine shaft construction method applying the same, and belongs to the technical field of mine shaft construction. The grouting pressure feeding method comprises the core steps of grouting preparation, segmented pressure feeding grouting, pressure feeding control and secondary grout supplementing pressure feeding, and the problems that in the prior art, in the grouting pressure feeding process, grout tiny backflow is prone to being neglected, consolidation is not dense, and the pressure feeding efficiency is low are solved by limiting the pressure feeding pressure interval of single-liquid grout and double-liquid grout and optimizing the shutdown rhythm of the pressure stabilizing stage. And a grouting channel is easy to block, and the efficiency is low. The mine shaft construction process applying the method adapts to complex surrounding rock conditions such as strong weathering and rich water, the technical effects of accurate pressure feeding of grout, backflow restraining and consolidation compactness improving are finally achieved, the safety and efficiency of mine shaft construction are effectively guaranteed, and the method can be widely adapted to various complex grouting reinforcement engineering scenes of mine shafts.

Description

Technical Field

[0001] This invention relates to the field of mine shaft construction technology, specifically to a grouting and injection method and a mine shaft construction method using the injection method. Background Technology

[0002] During the construction of mine shafts, when encountering complex surrounding rock conditions such as strong weathering and abundant water, problems such as shaft wall collapse and water inrush are prone to occur, seriously affecting construction safety and progress. Grouting reinforcement is the core technical means to solve the above problems. Its core lies in the precise injection of grout into the fissures of the surrounding rock through grouting pipes, so as to consolidate the surrounding rock and improve its bearing capacity.

[0003] In existing grouting and pressure delivery methods, a fixed pressure delivery mode is mostly adopted. During the two-liquid grout stabilization stage, the stabilizing pressure is usually maintained continuously, ignoring the slight backflow phenomenon caused by gravity. Because the backflow volume is small and there is no obvious visual manifestation, this backflow phenomenon is easily overlooked in actual construction. However, long-term accumulation can lead to voids in the micro-cracks of the surrounding rock, resulting in incomplete consolidation, which in turn affects the grouting reinforcement effect and creates safety hazards such as later deformation and collapse of the well wall.

[0004] Meanwhile, in the existing grouting and pressurization process, the grouting pipe openings are easily blocked by grout deposits, affecting the grout diffusion efficiency; moreover, the grouting parameters are not precisely controlled and are difficult to adapt to surrounding rock conditions with different fracture openings, resulting in grout waste or insufficient filling. In addition, the existing grouting and pressurization methods are not well adapted to the construction process of mine shafts, failing to form a complete integrated construction plan and resulting in low construction efficiency.

[0005] Therefore, there is an urgent need for a grouting pressure delivery method that can solve the above-mentioned hidden problems, improve the grouting effect, and be suitable for the construction scenario of mine shafts, as well as a mine shaft construction method that applies this method. Summary of the Invention

[0006] The purpose of this invention is to provide a grouting and pumping method and a mine shaft construction method using this pumping method, so as to achieve precise pumping of grout, suppress backflow, and improve the consolidation quality.

[0007] The above-mentioned technical objective of the present invention is achieved through the following technical solution: A grouting and pressurization method includes the following steps: (1) Grouting preparation: Use grouting pipes with perforations as pressure delivery channels, drive the grouting pipes into the pre-drilled holes and weld them together with ring steel bars to form an integral structure; (2) Segmented pressure delivery grouting: The segmented pressure delivery mode of “single liquid grout + double liquid grout” is adopted. First, cement single liquid grout is pressed into the grouting pipe, and then cement-water-water glass double liquid grout is pressed into the grouting pipe. By controlling the grouting pressure, the aluminum foil is regularly broken along the scoring line to achieve precise pressure delivery of grout into the surrounding rock fissures. (3) Pressure control: During the pressure delivery process, the grouting pressure is controlled. The pressure delivery pressure of single-liquid cement grout is controlled at 5-6 MPa, and the pressure delivery pressure of double-liquid grout is controlled at 6-8 MPa. The pressure stabilization time after double-liquid grout delivery is not less than 5 minutes. The end of pressure delivery is judged by the dual control standard of final pressure and grouting volume. During the pressure stabilization stage of double-liquid grout, the grouting pump is briefly stopped for 10 seconds every 1 minute. During the stop, the pressure in the grouting pipe is kept constant. (4) Secondary grouting and pressurization: When the consolidation of the surrounding rock after grouting does not meet the design requirements, the original grouting pipe is used. The appropriate aluminum foil of the corresponding specification is selected according to the geological conditions to match the grouting pressure. The grouting pressure is controlled to be ≥5MPa. The aluminum foil fragments and residual grout are pushed open to carry out grouting and pressurization.

[0008] In a preferred embodiment, the grouting pipe in step (1) has multiple φ10mm eyelets evenly distributed within a 100mm range at one end. The inner end of the eyelet is machined with an inner conical groove. An aluminum foil with folded edges and scoring lines is embedded in the inner conical groove, and the aluminum foil is fixed by welding points.

[0009] In a preferred embodiment, the inner conical groove has a taper of 20°, a length of 3 mm, a large end diameter of φ13 mm, a small end diameter of φ10 mm, and a conical surface roughness Ra≤1.6 μm.

[0010] In a preferred embodiment, the aluminum foil has a thickness of 0.12-0.18 mm, a diameter of φ12 mm, a pre-made cross-shaped etched line in the center, a etched depth of 2 / 3 of the aluminum foil thickness, and a etched length of 4 mm.

[0011] In a preferred embodiment, the aluminum foil has three folded edges evenly arranged around its circumference. The folded edges are integrally stamped with the aluminum foil, with an inclination angle of 30° and a height of 0.2 mm, facing the inside of the grouting pipe.

[0012] In a preferred embodiment, the aluminum foil includes three specifications, namely: Specification A: 0.12mm thick with shallow grooves, punching pressure 2MPa; Specification B: 0.15mm thick + medium groove, punching pressure 3MPa; Specification C: 0.18mm thick + deep marks, punching pressure 4MPa.

[0013] In a preferred embodiment, the aluminum foil is fixed by two solder joints located on the outside of the folded edge.

[0014] In a preferred embodiment, the ratio of the single-liquid cement slurry in step (2) is cement:water = 1:0.5, and the ratio of the double-liquid slurry is cement:water:water glass = 0.5:1:0.5.

[0015] In a preferred embodiment, the grouting and pressurizing in step (2) adopts the pore-separated grouting method, and the pressurizing sequence is adjusted when cross-grouting occurs.

[0016] 1. A method for constructing a mine shaft using the grouting and pressure delivery method, comprising the following steps: (1) Preliminary preparation: Clean and level the working face of the shaft, set up a temporary water pit and water pump in the center of the shaft for drainage; project the drilling position onto the bottom plate according to the design, debug the down-the-hole drill and check the integrity of the drill bit; (2) Deep hole drilling: Drill rock according to the designed angle, orientation and depth. The drilling angle error is ≤ ±0.5º. The drilling starts with a low impact and low propulsion mode. The propulsion pressure is adjusted according to the drilling depth. The deviation is corrected in real time with a surveying instrument. After the hole is formed, the sand and gravel in the hole are cleaned and the pipe opening is sealed. (3) Grouting pipe installation and grouting pumping: The grouting pipe installation and grouting pumping operation are completed using the grouting pumping method described above; (4) Monitoring and subsequent construction: During the construction process, monitor the grout diffusion and stratum deformation. After the grouting is completed, check the consolidation status of the surrounding rock. If the standard is met, use weak blasting combined with a small excavator to excavate the shaft. After acceptance, carry out steel reinforcement binding, formwork installation and concrete pouring.

[0017] Compared with the prior art, the present invention has the following beneficial effects: 1. In the existing technology, the pressure stabilization stage of grouting and pressurization generally adopts a continuous high-pressure stabilization mode. This mode not only fails to solve the problem of slight backflow of grout caused by gravity, but also causes the grouting equipment to be under load, resulting in pressure fatigue and affecting the accuracy of pressure control. Furthermore, the slight backflow of grout, due to its small flow rate and lack of visual manifestation, will accumulate over a long period of time and cause voids in the surrounding rock micro-cracks, resulting in poor consolidation and creating safety hazards such as deformation and collapse of the well wall in the later stage. This invention solves the hidden problem of insufficient consolidation in existing technologies by setting a control rhythm of "short pause for 10 seconds every 1 minute" during the dual-liquid slurry pressure stabilization stage, and strictly maintaining the pressure inside the grouting pipe during the pause. It utilizes the inertial slurry stagnation effect at the moment of stop to break the balance between the gravity backflow of slurry and the pressure inside the pipe, and to squeeze the backflowing slurry back into the surrounding rock fissures. At the same time, the short pause allows the grouting equipment to have a brief rest, avoids pressure fatigue, improves pressure control accuracy, further ensures grouting uniformity, and ultimately significantly improves the consolidation density of the surrounding rock, effectively reduces the safety hazards of later well wall deformation and collapse, and improves the reliability of grouting reinforcement. 2. In existing technologies, conventional grouting and pressure delivery methods do not differentiate between single-liquid and double-liquid grouts, employing a uniform pressure delivery. This fails to adapt to the penetration requirements of different grouts and lacks flexible adjustment schemes for complex working conditions such as strongly weathered and water-rich mine shafts. Consequently, under complex surrounding rock conditions, either insufficient grout penetration and inadequate filling occur, or excessive pressure damages the surrounding rock structure, resulting in poor adaptability. This invention explicitly limits the single-liquid grout delivery pressure to 5-6 MPa to meet the needs of filling shallow fissures, and the double-liquid grout delivery pressure to 6-8 MPa to meet the needs of penetrating deep and dense fissures. By matching the penetration characteristics of different grouts, this method can be widely adapted to various complex construction scenarios in mine shafts. Whether it is the reinforcement of strongly weathered surrounding rock or the water-blocking grouting of water-rich surrounding rock, it can be flexibly adjusted without the need to redesign grouting schemes for different working conditions, thus improving the versatility and adaptability of construction. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the arrangement structure of the grouting pipes in a grouting pressure delivery method according to the present invention.

[0019] Figure 2 This is a schematic diagram of the structure of a grouting pipe for a grouting pressure delivery method according to the present invention.

[0020] Figure 3 This is a schematic diagram of the structure of the grouting pipe in a grouting pressure delivery method according to the present invention.

[0021] Figure 4 This is a schematic diagram of the aluminum foil structure of the grouting pipe in a grouting pressure delivery method according to the present invention. In the picture

[0022] 1. Grouting pipe; 2. Eyelet; 3. Inner conical groove; 4. Aluminum foil; 5. Score line; 6. Folded edge; 7. Rubber positioning ring. Detailed Implementation

[0023] The present invention will be further described in detail below with reference to the accompanying drawings.

[0024] This specific embodiment is merely an explanation of the present invention and is not intended to limit the invention. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they are within the scope of the claims of the present invention. Example 1

[0025] Reference Figures 1 to 2 As shown, a grouting and pressurization method includes the following steps: (1) Grouting preparation: Use grouting pipes with perforations as pressure delivery channels, drive the grouting pipes into the pre-drilled holes and weld them together with ring steel bars to form an integral structure; (2) Segmented pressure delivery grouting: The segmented pressure delivery mode of “single liquid grout + double liquid grout” is adopted. First, cement single liquid grout is pressed into the grouting pipe, and then cement-water-water glass double liquid grout is pressed into the grouting pipe. By controlling the grouting pressure, the aluminum foil is regularly broken along the scoring line to achieve precise pressure delivery of grout into the surrounding rock fissures. (3) Pressure control: During the pressure delivery process, the grouting pressure is controlled. The pressure delivery pressure of single-liquid cement grout is controlled at 5-6 MPa, and the pressure delivery pressure of double-liquid grout is controlled at 6-8 MPa. The pressure stabilization time after double-liquid grout delivery is not less than 5 minutes. The end of pressure delivery is judged by the dual control standard of final pressure and grouting volume. During the pressure stabilization stage of double-liquid grout, the grouting pump is briefly stopped for 10 seconds every 1 minute. During the stop, the pressure in the grouting pipe is kept constant. (4) Secondary grouting and pressurization: When the consolidation of the surrounding rock after grouting does not meet the design requirements, the original grouting pipe is used. The appropriate aluminum foil of the corresponding specification is selected according to the geological conditions to match the grouting pressure. The grouting pressure is controlled to be ≥5MPa. The aluminum foil fragments and residual grout are pushed open to carry out grouting and pressurization.

[0026] During construction, the grouting pipes are first installed and fixed. Multiple grouting pipes are welded together using ring-shaped steel bars to form an integral structure, preventing displacement or loosening during the pressure delivery process. Then, a segmented pressure delivery mode is adopted. First, a single-component cement grout is delivered at a pressure of 5-6 MPa, utilizing its good fluidity to initially fill shallow fissures in the surrounding rock. Next, a cement-water-water glass dual-component grout is delivered at a pressure of 6-8 MPa. By controlling the pressure, the aluminum foil inside the grouting pipe's perforation is regularly broken along the scoring lines, ensuring uniform and precise penetration of the grout into deep fissures in the surrounding rock. After the dual-component grout delivery is completed, a pressure stabilization phase begins, with a stabilization time of no less than 5 minutes. The dual control of final pressure and grouting volume ensures that the grout fully fills the cracks and completes the initial consolidation. The operation of stopping for 10 seconds every 1 minute without depressurizing can break the gravity backflow balance by utilizing the inertial stagnation of the grout, and squeeze the backflowing slurry back into the cracks to avoid voids in the cracks. If the consolidation of the surrounding rock after grouting does not meet the design requirements, the original grouting pipe can be used and aluminum foil of appropriate specifications can be selected. The aluminum foil fragments and residual grout can be pushed open with a pressure of not less than 5MPa to replenish the grout. There is no need to re-lay the grouting pipe, which not only improves the construction efficiency, but also ensures that the consolidation of the surrounding rock meets the design standards and provides stable surrounding rock conditions for subsequent construction.

[0027] Furthermore, in step (1), multiple φ10mm eyelets are evenly distributed within a 100mm range at one end of the grouting pipe. An inner conical groove is machined at the inner end of the eyelet, and an aluminum foil with folded edges and scoring lines is embedded in the inner conical groove. The aluminum foil is fixed by welding points.

[0028] Multiple φ10mm perforations evenly distributed within a 100mm range at one end of the grouting pipe provide a uniform outflow channel for the grout, ensuring that the grout can fully cover the surrounding rock fissures around the grouting pipe. The inner conical groove machined at the inner end of the perforation hole can embed and seal the aluminum foil, preventing sand and gravel from entering the grouting pipe and clogging the channel before pressure injection, while providing a stable stress surface for the aluminum foil. After the aluminum foil with folded edges and scoring lines is embedded in the inner conical groove, it is fixed by welding points to ensure the sealing performance between the aluminum foil and the perforation hole, preventing the grout from leaking prematurely before reaching the preset pressure. The scoring line design guides the aluminum foil to break through the scoring lines regularly when the set grouting pressure is reached, avoiding irregular fragments from the broken aluminum foil that would clog the perforation hole, ensuring that the grout can smoothly and accurately enter the surrounding rock fissures.

[0029] Furthermore, the inner conical groove has a taper of 20°, a length of 3mm, a large end diameter of φ13mm, a small end diameter of φ10mm, and a conical surface roughness Ra≤1.6μm.

[0030] The inner conical groove features a 20° taper, a 3mm length, and a 13mm diameter at the large end and a 10mm diameter at the small end, precisely matching the 10mm diameter of the grouting pipe's perforation. This ensures that the aluminum foil is smoothly embedded and tightly adheres to the conical surface, while also providing a uniform impact force to the aluminum foil under grouting pressure, guiding it to break regularly along the scoring line. The conical surface roughness is controlled at Ra≤1.6μm, reducing friction between the aluminum foil and the conical surface and preventing irregular breakage due to excessive friction. It also improves the sealing performance between the aluminum foil and the conical surface, preventing grout leakage from the gap between the aluminum foil and the conical surface, further ensuring the stability of the grouting pressure and the accuracy of grout delivery.

[0031] Furthermore, the aluminum foil has a thickness of 0.12-0.18 mm, a diameter of φ12 mm, a pre-made cross-shaped etched line in the center, a etched depth of 2 / 3 of the aluminum foil thickness, and a etched length of 4 mm.

[0032] The aluminum foil thickness is controlled at 0.12-0.18mm, with a diameter of φ12mm, which can precisely fit the size of the inner conical groove, ensuring that the aluminum foil can be tightly embedded in the groove without affecting the flow of grout in the hole. The pre-made cross-shaped scribe line in the center, with a scribe depth of 2 / 3 of the aluminum foil thickness and a scribe length of 4mm, can ensure that the aluminum foil has sufficient sealing strength when the preset pressure is not reached, preventing grout leakage. At the same time, when the grouting pressure reaches the set value, the aluminum foil will break precisely and regularly along the scribe line, avoiding the generation of small fragments after the aluminum foil breaks, which will block the hole or the tiny cracks in the surrounding rock. This ensures that the grout can smoothly penetrate into the cracks and improve the grouting effect.

[0033] Furthermore, the aluminum foil has three folded edges evenly arranged around its circumference. The folded edges are integrally stamped with the aluminum foil, with an inclination angle of 30° and a height of 0.2mm, facing the inside of the grouting pipe.

[0034] The three evenly spaced folds along the circumference of the aluminum foil, integrally stamped with the foil, ensure structural strength and prevent folds from detaching. The 30° tilt angle, 0.2mm height, and inward orientation towards the grouting pipe allow the folds to fit tightly against the conical surface after the foil is embedded, further enhancing the sealing performance and preventing grout leakage from the foil edges. Simultaneously, the folds increase the contact area between the foil and the conical surface, resulting in more even stress distribution under grouting pressure. This ensures the foil breaks regularly along the scoring lines, preventing irregular breakage due to uneven stress and guaranteeing smooth grout delivery.

[0035] Furthermore, the aluminum foil includes three specifications, namely: Specification A: 0.12mm thick with shallow grooves, punching pressure 2MPa; Specification B: 0.15mm thick + medium groove, punching pressure 3MPa; Specification C: 0.18mm thick + deep marks, punching pressure 4MPa.

[0036] Three different specifications of aluminum foil, through the combination of thickness and notch depth, create different grouting pressures, which can be flexibly selected according to different geological conditions and the opening of surrounding rock fissures: For working conditions with larger fissure openings and requiring lower pressure to achieve grout penetration, specification A aluminum foil is selected, and the 2MPa grouting pressure ensures that the grout flows out smoothly without damaging the surrounding rock due to excessive pressure; for working conditions with medium fissure openings, specification B aluminum foil is selected, and the 3MPa grouting pressure balances grout penetration efficiency and surrounding rock protection; for working conditions with smaller fissure openings and requiring higher pressure to achieve grout penetration, specification C aluminum foil is selected, and the 4MPa grouting pressure ensures that the grout can effectively penetrate into the micro-fissures, achieving precise grouting under different working conditions and improving the adaptability and effect of grouting.

[0037] Furthermore, the aluminum foil is fixed by two solder joints located on the outside of the folded edge.

[0038] The aluminum foil is fixed by two welding points located on the outside of the folded edge. This ensures a firm connection between the aluminum foil and the conical groove inside the grouting pipe, preventing the aluminum foil from falling off or shifting due to pressure impact during the pressing process. It also avoids the welding points affecting the scoring line structure of the aluminum foil, ensuring that the aluminum foil breaks regularly along the scoring line when the preset pressure is reached. The symmetrical arrangement of the two welding points ensures that the aluminum foil is subjected to uniform force, avoiding premature damage caused by uneven force due to single-point fixing. At the same time, the welding points are located on the outside of the folded edge, so they will not block the grouting pipe channel or affect the smooth flow of grout, further ensuring the stability of the grouting pressing process.

[0039] Furthermore, the ratio of the single-liquid cement slurry in step (2) is cement:water = 1:0.5, and the ratio of the double-liquid cement slurry is cement:water:water glass = 0.5:1:0.5.

[0040] The single-component cement grout uses a cement:water ratio of 1:0.5, ensuring good fluidity and adhesion. It can flow smoothly through the grouting pipe openings and quickly fill shallow fissures in the surrounding rock, forming a preliminary consolidation layer, laying the foundation for subsequent two-component grout injection. The two-component grout uses a cement:water:water glass ratio of 0.5:1:0.5. The addition of water glass accelerates the grout's setting speed, preventing excessive diffusion and waste within the fissures. It also enhances the grout's consolidation strength, allowing the two-component grout to quickly penetrate deep into dense fissures in the surrounding rock and complete consolidation, forming a high-strength consolidated body. This effectively improves the bearing capacity and stability of the surrounding rock, achieving comprehensive reinforcement of both shallow and deep fissures.

[0041] Furthermore, in step (2), the grouting and pressurizing adopts the grouting method with intermittent grouting, and the pressurizing sequence is adjusted when cross-grouting occurs.

[0042] Grouting and pressurization employs a staggered injection method, where grout is injected through one or more alternate grouting holes. This avoids interference between grout from adjacent holes and prevents cross-flow of grout before it has fully penetrated into the fissures. This ensures that the grout from each hole can penetrate evenly and fully into the surrounding rock fissures, improving the uniformity of grouting. If cross-flow occurs during construction, the pressurization sequence can be adjusted in time to avoid cross-flow channels, ensuring that the grout fills the target fissures as designed, avoiding grout waste, and guaranteeing the overall effect of grouting reinforcement. This ensures that the consolidation quality of all areas of the surrounding rock meets the design standards.

[0043] In this embodiment, during the dual-liquid grout pressure stabilization stage, each time the grouting pump is restarted, the grouting pressure is first instantly increased to 9-10 MPa, held for 2-3 seconds, and then dropped back to 6-8 MPa to maintain stable pressure. This high-pressure pulse impact, combined with the physical scraping effect of the aluminum foil folded edge residue, removes grout deposits at the grouting pipe openings, achieving self-cleaning of the grouting channel and preventing micro-cracks from being blocked by grout.

[0044] During the dual-liquid grout stabilization stage, each time the grouting pump restarts after a short 10-second pause, the pressure is instantly increased to 9-10 MPa and maintained for 2-3 seconds. This high-pressure pulse generates a strong impact force, acting on the grouting pipe openings. Simultaneously, the folded edges remaining after the aluminum foil is broken will vibrate slightly under the high-pressure pulse, creating a physical scraping effect. The combination of these two factors effectively removes blockages formed by the initial setting or deposition of grout at the openings, achieving self-cleaning of the grouting channel. Subsequently, the pressure is reduced to 6-8 MPa for continued stabilization, ensuring that the grout continuously and smoothly penetrates into the surrounding rock fissures. This prevents the grout from being unable to flow out normally due to blockage at the openings, and prevents insufficient filling of micro-fissures due to insufficient grout supply. This further improves the density of the surrounding rock consolidation and ensures the stability and reliability of the grouting reinforcement effect. Example 2

[0045] A method for constructing a mine shaft using the grouting and pressure-feeding method described in Embodiment 1 includes the following steps: (1) Preliminary preparation: Clean and level the working face of the shaft, set up a temporary water pit and water pump in the center of the shaft for drainage; project the drilling position onto the bottom plate according to the design, debug the down-the-hole drill and check the integrity of the drill bit; (2) Deep hole drilling: Drill rock according to the designed angle, orientation and depth. The drilling angle error is ≤ ±0.5º. The drilling starts with a low impact and low propulsion mode. The propulsion pressure is adjusted according to the drilling depth. The deviation is corrected in real time with a surveying instrument. After the hole is formed, the sand and gravel in the hole are cleaned and the pipe opening is sealed. (3) Grouting pipe installation and grouting pumping: The grouting pipe installation and grouting pumping operation are completed using the grouting pumping method described in Example 1; (4) Monitoring and subsequent construction: During the construction process, monitor the grout diffusion and stratum deformation. After the grouting is completed, check the consolidation status of the surrounding rock. If the standard is met, use weak blasting combined with a small excavator to excavate the shaft. After the acceptance is qualified, carry out steel reinforcement binding, formwork installation and concrete pouring. Multiple grouting pipes are evenly arranged around the circumference of the vertical shaft, with a center-to-center distance of 30-50cm between adjacent grouting pipes. Two rubber positioning rings are fitted on the outer wall of the grouting pipe near the orifice.

[0046] Before construction, the working face of the shaft is cleaned and leveled, and temporary water pits and water pumps are set up for drainage to prevent water accumulation on the working face from affecting the drilling and grouting quality. Simultaneously, the drilling position is accurately projected, the down-the-hole drill is adjusted, and the drill bit is inspected to ensure accurate drilling later. For deep hole drilling, rock is drilled according to the designed angle, orientation, and depth, controlling the angle error to no more than ±0.5º. A low-impact, low-advance mode is used when drilling begins, adjusting the advance pressure as the depth increases and correcting deviations in real time to ensure drilling accuracy and prevent deviations that could prevent the precise installation of the grouting pipe. After drilling, sand and gravel are removed, and the pipe openings are sealed to prevent debris from entering the hole and blocking the passage. The grouting pipes are evenly arranged along the circumference of the shaft, with an adjacent spacing of 30-50cm to ensure... The grout completely covers the surrounding rock of the shaft, leaving no blind spots. Rubber positioning rings can fix the position of the grouting pipe, preventing displacement during the grouting process. Grouting is then completed using the grouting pressure delivery method described in Example 1. During construction, the grout diffusion and stratum deformation are monitored to detect abnormalities and adjust parameters in a timely manner. After grouting, the consolidation status of the surrounding rock is checked. Once it meets the standards, weak blasting combined with a small excavator is used for excavation, which avoids blasting impact damage to the reinforced surrounding rock. After acceptance, steel reinforcement binding, formwork installation, and concrete pouring are carried out to form a complete shaft wall support structure. The entire process is coherent and orderly, effectively ensuring the safety and progress of mine shaft construction and adapting to the needs of shaft construction under complex surrounding rock conditions.

[0047] After grouting using the method described in this case, all fissures in the surrounding rock were fully filled with grout, with no voids, cavities, or unfilled areas, resulting in good consolidation. The grout setting performance was tested on-site, and the cement grout had good fluidity and no segregation. After secondary grouting, the consolidation of the surrounding rock met the design requirements, with no fissure re-opening or leakage issues.

[0048] The shaft wall is free from the risks of settlement, collapse, and leakage, and the integrity of the shaft wall is good. The construction process is safe and controllable, with no equipment failures or safety hazards. It is fully adapted to the construction needs of mine shafts under complex geological conditions such as strong weathering and water abundance.

[0049] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Unless otherwise specified, an element defined by the phrase "comprising..." or "including..." does not exclude the presence of additional elements in the process, method, article, or terminal device that includes said element. Additionally, in this document, "greater than," "less than," "exceeding," etc., are understood to exclude the stated number; "above," "below," "within," etc., are understood to include the stated number.

[0050] The above description of the embodiments is provided to facilitate understanding and use of the present invention by those skilled in the art. It is obvious to those skilled in the art that various modifications can be easily made to the embodiments, and the general principles described herein can be applied to other embodiments without creative effort. Therefore, the present invention is not limited to the above embodiments. Improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the protection scope of the present invention.

Claims

1. A grouting and pressurization method, characterized in that, Includes the following steps: (1) Grouting preparation: The grouting pipe with a perforated hole is used as the pressure delivery channel. The grouting pipe is driven into the pre-drilled hole and welded with ring steel bars to form an integral structure. (2) Segmented pressure grouting: The segmented pressure grouting mode of "single liquid grout + double liquid grout" is adopted. First, cement single liquid grout is pressed into the grouting pipe, and then cement-water-water glass double liquid grout is pressed into the grouting pipe. (3) Pressure control: During the pressure delivery process, the grouting pressure is controlled. The pressure delivery pressure of single-liquid cement grout is controlled at 5-6 MPa, and the pressure delivery pressure of double-liquid grout is controlled at 6-8 MPa. The pressure stabilization time after double-liquid grout delivery is not less than 5 minutes. The end of pressure delivery is judged by the dual control standard of final pressure and grouting volume. During the pressure stabilization stage of double-liquid grout, the grouting pump is briefly stopped for 10 seconds every 1 minute. During the stop, the pressure in the grouting pipe is kept constant. During the pressure stabilization stage of double-liquid grout, each time the grouting pump is restarted, the grouting pressure is first increased to 9-10 MPa instantly, and then dropped back to 6-8 MPa to maintain the pressure stabilization after 2-3 seconds. (4) Secondary grouting and pressurization: When the consolidation of the surrounding rock after grouting does not meet the design requirements, the original grouting pipe is used, and the grouting pressure is controlled to be ≥5MPa.

2. The grouting and pressurizing method according to claim 1, characterized in that, In step (1), multiple φ10mm eyelets are evenly distributed within a 100mm range at one end of the grouting pipe. An inner conical groove is machined at the inner end of the eyelet. An aluminum foil with folded edges and scoring lines is embedded in the inner conical groove. The aluminum foil is fixed by welding points.

3. The grouting and pressurizing method according to claim 2, characterized in that, The inner conical groove has a taper of 20°, a length of 3mm, a large end diameter of φ13mm, a small end diameter of φ10mm, and a surface roughness Ra≤1.6μm.

4. The grouting and pressurizing method according to claim 2, characterized in that, The aluminum foil has a thickness of 0.12-0.18 mm, a diameter of φ12 mm, a pre-made cross-shaped etched line in the center, a etched depth of 2 / 3 of the aluminum foil thickness, and a etched length of 4 mm.

5. The grouting and pressurizing method according to claim 4, characterized in that, The aluminum foil has three folded edges evenly arranged around its perimeter. The folded edges are integrally stamped with the aluminum foil, with an inclination angle of 30° and a height of 0.2mm, facing the inside of the grouting pipe.

6. The grouting and pressurizing method according to claim 4, characterized in that, The aluminum foil comes in three specifications: Specification A: 0.12mm thick with shallow grooves, punching pressure 2MPa; Specification B: 0.15mm thick + medium groove, punching pressure 3MPa; Specification C: 0.18mm thick + deep marks, punching pressure 4MPa.

7. The grouting and pressurizing method according to claim 2, characterized in that, The aluminum foil is fixed by two solder joints located on the outside of the folded edge.

8. The grouting and pressurizing method according to claim 1, characterized in that, The ratio of the single-liquid cement slurry in step (2) is cement:water = 1:0.5, and the ratio of the double-liquid cement slurry is cement:water:water glass = 0.5:1:0.

5.

9. The grouting and pressurizing method according to claim 1, characterized in that, In step (2), the grouting and pressure delivery adopts the pore-hole injection method.

10. A method for constructing a mine shaft using the grouting and pressure-feeding method according to any one of claims 1-9, characterized in that, Includes the following steps: (1) Preliminary preparation: Clean and level the working face of the shaft, set up a temporary water pit and water pump in the center of the shaft for drainage; project the drilling position onto the bottom plate according to the design, debug the down-the-hole drill and check the integrity of the drill bit; (2) Deep hole drilling: Drill rock according to the designed angle, orientation and depth. The drilling angle error is ≤ ±0.5º. The drilling starts with a low impact and low propulsion mode. The propulsion pressure is adjusted according to the drilling depth. The deviation is corrected in real time with a surveying instrument. After the hole is formed, the sand and gravel in the hole are cleaned and the pipe opening is sealed. (3) Grouting pipe installation and grouting pumping: The grouting pipe installation and grouting pumping operation shall be completed by any of the grouting pumping methods described in claims 1-9; (4) Monitoring and subsequent construction: During the construction process, monitor the grout diffusion and stratum deformation. After the grouting is completed, check the consolidation status of the surrounding rock. If the standard is met, use weak blasting combined with a small excavator to excavate the shaft. After acceptance, carry out steel reinforcement binding, formwork installation and concrete pouring.

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