A quick hole plugging bag for roadway excavation and application thereof

Abstract

The application discloses a kind of blast hole rapid plugging bag for roadway excavation and application, belong to mining technical field.The plugging bag is composed of two-component polyurethane system, and is packaged using multi-layer composite aluminum foil bag:A component is isocyanate and modifier, B component contains polyol, blowing agent and composite system containing trimerization catalyst;When used on site, it is rapidly activated and mixed, packed to blast hole plugging section, rapidly foamed and solidified in hole, forming high-strength, high-closed-cell-rate and tightly bonded polyurethane foam plugging body with hole wall, which can effectively seal explosive gas, significantly improve blasting stress wave energy and explosion gas action time, thereby improving rock breaking effect, reducing explosive unit consumption, effectively controlling harmful effects such as flyrock and shock wave;The present application solves the core problems of traditional blast hole plugging construction, poor sealing and low strength by using stable packaging and specific reaction system, providing an efficient, safe and convenient plugging solution for blasting engineering.

Description

Technical Field

[0001] This invention relates to the field of mining technology, specifically to a rapid hole sealing kit for tunnel excavation and its application. Background Technology

[0002] With the continuous deepening of the concept of efficient and safe underground mining, rock drilling and blasting technology has been comprehensively promoted and innovated. Underground rock drilling and blasting technology is a key link in realizing ore and rock crushing and mining. Among them, the quality of borehole sealing is one of the core elements of blasting effect, which is crucial to mine production efficiency and safety. The compactness and stability of borehole sealing are important aspects of the blasting process. The quality of sealing directly determines the utilization efficiency of blasting energy, which is related to the control of mine blasting costs and the quality of ore and rock crushing, affecting the stability of the surrounding rock and the safety of the working environment, and even the progress of the overall mine mining. Precise and controllable blasting process is an important guarantee for achieving efficient, low-consumption, and safe underground mining.

[0003] After the explosive in the borehole detonates, the shock wave propagates into the packing structure, causing it to compress. Subsequently, the expansion pressure of the detonating gas overcomes the sliding friction between the packing structure and the borehole wall, as well as the weight of the packing structure itself, resulting in a projectile motion of the packing structure. Therefore, the motion of the packing structure can be roughly divided into two stages: the first stage is the microscopic wave stage under the impact of the blast shock wave, and the second stage is the macroscopic motion stage under the action of the detonating gas. Therefore, if the blast holes are not sealed or the sealing quality is poor, it will directly cause a series of serious problems: First, it will lead to a large leakage of explosive energy, causing a sharp increase in explosive consumption per blast and a low single-blast advance, significantly increasing mining costs; Second, it will cause air shock waves and flyrock to exceed the standard distance, seriously threatening the safety of personnel, equipment and structures underground, and constituting a major safety hazard; Third, it will reduce the uniformity of rock fragmentation, leading to an increase in the proportion of large pieces, directly affecting the efficiency of subsequent loading, transportation and crushing processes, forming a production bottleneck; Fourth, it will exacerbate the diffusion of blasting smoke and toxic gases, deteriorate the underground working environment, and endanger the health of personnel.

[0004] Traditional borehole sealing materials mainly consist of two types: bulk materials (sand and gravel) and binder materials (yellow mud and clay). Bulk material sealing has the following obvious drawbacks: First, the material itself lacks cohesion and relies solely on gravity to accumulate, resulting in a loose bond with the borehole wall and difficulty in forming an effective resistance structure, leading to extremely low sealing strength. Second, it is easily blasted out as a whole in the initial stage of the explosion gas expansion, resulting in low energy sealing efficiency and severely insufficient utilization of explosion energy. Third, it cannot effectively seal the toxic and harmful gases produced by the explosion, causing the blasting fumes to diffuse and linger in rock fissures, worsening the ventilation environment and prolonging ventilation time. Fourth, bulk materials are mostly sourced from on-site rock debris, with random particle size distribution, making standardized sealing impossible, resulting in large fluctuations in blasting effects and poor controllability. The disadvantages of traditional sealing materials are as follows: First, the material preparation process is complex, requiring on-site soil sampling, mixing, and kneading, which is time-consuming and labor-intensive, severely restricting the efficiency of the tunneling cycle. If mass-produced on the surface, it may break during transportation. Second, the initial setting strength is low, making it easily "blown out" under the high-pressure shock wave generated by the explosion, leading to sealing failure and energy leakage. Third, the moisture content is difficult to control precisely; too dry results in poor compaction, while too wet leads to slow strength development, resulting in unstable sealing quality and significant influence from human factors. Fourth, the adhesion to the borehole wall is limited, especially in fractured rock strata, easily forming through-cracks and reducing sealing reliability. Fifth, the mixed borehole mud has already shrunk, resulting in poor sealing compaction and failing to achieve the expected sealing effect. Moreover, the traditional borehole sealing process is too cumbersome, requiring a large amount of manpower, making cost calculation difficult, and the sealing effect is poor. Therefore, most mines no longer use traditional sealing materials during blasting, and the boreholes used are not sealed.

[0005] Against this backdrop, developing a sealing package that is easy to use and has a good sealing effect has become an urgent need in the modern mining and engineering blasting field to improve safety, efficiency and economic benefits. Summary of the Invention

[0006] To address or partially address the problems existing in related technologies, this invention provides a rapid blast hole sealing package for tunnel excavation and its application. This rapid blast hole sealing package solves the technical problems of traditional sealing materials, such as cumbersome operation, unstable sealing quality, low energy utilization, significant safety hazards, and low operational efficiency. Through structural innovation and material optimization, it achieves safe, reliable, economical, and efficient standardized blast hole sealing. The rapid blast hole sealing package provided by this invention is simple to operate, convenient to construct, produces dense sealing, has strong pressure resistance, uniform blasting block size, concentrated blast pile, and large single-blast advance. Its process flow is as follows: Figure 1 As shown.

[0007] One objective of this invention is to provide a rapid sealing package for blast holes in tunnel excavation, which is a double-cavity integrated bag composed of three layers of composite aluminum foil bags. One cavity of the double-cavity integrated bag contains component A, which includes 80%-95% isocyanate and 5%-20% modifier by mass percentage. The other cavity contains component B, which includes 60%-75% polyol, 10%-20% foaming agent, 3%-6% catalyst, 1%-4% foam stabilizer and 0%-10% functional additives by mass percentage.

[0008] Preferably, the three-layer composite aluminum foil bag of the present invention consists of polyethylene, aluminum foil and polyester film from the inside out, with a heat-sealing strength of not less than 35N / 15mm and a thickness of not less than 0.10mm.

[0009] Preferably, the mass ratio of component A to component B in this invention is 1:(0.3-2).

[0010] Preferably, the isocyanate in component A of the present invention is polymethylene polyphenyl polyisocyanate (polymeric MDI), with a -NCO mass fraction of 30%–32%, an average functionality of 2.5–3.0, and a CAS number of 9016-87-9.

[0011] Preferably, the modifier in component A of the present invention is a polymer of toluene diamine and propylene oxide (TDA-EO polymer, CAS: 63641-63-4).

[0012] Preferably, the polyol of the present invention is composed of highly reactive polyether polyol, highly functional polyether polyol, aromatic polyester polyol and amine polyether polyol, and satisfies the following mass ratio: highly reactive polyether polyol: 30%-50%, highly functional polyether polyol: 20%-40%, aromatic polyester polyol: 10%-30%, amine polyether polyol: 5%-15%, wherein the hydroxyl value of the polyol is ≥300mgKOH / g.

[0013] Preferably, the foaming agent is selected from one or more of cyclopentane, n-pentane, and isopentane, in any proportion.

[0014] Preferably, the catalyst comprises, by mass percentage, 40%-65% gel catalyst, 30%-55% trimerizing catalyst, and 5-15% delayed equilibrium catalyst. The gel catalyst includes one of dimethylcyclohexylamine and N,N-dimethylbenzylamine, ensuring the reaction initiates within a 10-20 second kneading time, preventing delayed reaction that could result in the sealing pack failing to foam after being inserted into the borehole. The trimerizing catalyst includes one of pentamethyldiethylenetriamine and 1,3,5-tris(dimethylaminopropyl)-1,3,5-hexahydrotriazine. Experimental results show that when the mass percentage of trimerizing catalyst is below 30%, the foam is prone to structural collapse during simulated bursting tests (high-temperature impact). The delayed equilibrium catalyst is 2-hydroxy-N,N,N-trimethyl-1-propylaminocarbamate; a content exceeding 15% can lead to an excessively slow reaction, affecting the sealing speed; a content below 5% can easily lead to uncontrolled reaction and large pores.

[0015] Preferably, the foam stabilizer is a polyether siloxane.

[0016] Preferably, the functional additives include one or more of flame retardants, reinforcing fillers, or toughening agents, in any proportion.

[0017] The second objective of this invention is to propose the application of the aforementioned rapid borehole sealing package, the specific steps of which are: cleaning the borehole, fully mixing component A and component B in the rapid borehole sealing package, and then inserting it into the predetermined position of the borehole.

[0018] To ensure effective sealing, the rapid sealing kit described in this invention should adhere to the following principles: (1) The sealing bag must not come into direct contact with the explosive, otherwise the explosion stress wave will have a cutting effect on it, causing premature failure.

[0019] (2) The sealing bag must not be exposed outside the blast hole to avoid cracking due to stress concentration and uneven expansion, and also to avoid insufficient friction due to reduced contact area.

[0020] In summary, Group A (black component) uses a polymer of isocyanate, toluene diamine, and propylene oxide as its core, while Group B (white component) utilizes polyols, foaming agents, catalysts, foam stabilizers, and functional additives to synthesize and foam polyurethane foam. This foam seals the pores, solidifying to form a high-strength, high-closed-cell-ratio polyurethane foam sealant that is tightly bonded to the pore walls. The reaction products are as follows: Figure 2 As shown.

[0021] Beneficial effects of this invention: (1) Excellent sealing effect: Polyurethane foam is formed in situ in the plugging section after the blast hole is loaded. The in situ foamed polyurethane foam pushes the aluminum foil bag to bond tightly with the blast hole wall, which can perfectly fill all the uneven gaps in the hole wall and form a "tailor-made" sealing plug, which greatly reduces the early leakage of explosive gas; this allows the pressure in the blast hole to be established and maintained more effectively.

[0022] (2) High strength and high energy resistance: Through formulation design, especially the introduction of isocyanurate structure, the cured foam has excellent compressive strength and impact resistance; it can more effectively couple and transfer the explosion energy to the rock mass, and enhance the stress wave peak value and energy transfer efficiency.

[0023] (3) Extending the gas action time: The high sealing and high strength of the sealing body effectively prevents the escape of the explosive gas and significantly extends the quasi-static pressure action time of the gas in the borehole, thereby enhancing the shearing, throwing and crushing effect of the rock.

[0024] (4) Improved overall blasting efficiency: ① Improve energy utilization: Under the same explosive consumption, the fragment size is more uniform and the proportion of large fragments is reduced.

[0025] ② Reduce explosive consumption: To achieve the same crushing effect, the amount of explosives used can be reduced by about 5%-15%.

[0026] ③ Control harmful effects: Reduce punching, reduce the intensity of air shock waves and the distance of flying rocks, and improve the safety of blasting.

[0027] ④ Improve blasting pattern: It is conducive to forming a more regular slope and excavation outline.

[0028] (5) Simplified hole plugging construction: The operation is extremely simple and quick, requiring no large equipment. A single person can complete a high-quality plugging of a blast hole in a few minutes. The construction efficiency is 5-10 times higher than the traditional method, and it is not affected by the blast hole angle or a small amount of seepage.

[0029] (6) Stable and reliable storage and transportation: The aluminum foil bag composite packaging ensures the long-term storage stability and immediate reliability of the product in the complex environment of the construction site. Attached Figure Description

[0030] Figure 1 This is a process flow diagram of the present invention.

[0031] Figure 2 It is the product of the reaction of components AB of this invention.

[0032] Figure 3 This is the natural state of the present invention.

[0033] Figure 4 This is the expanded state of the present invention.

[0034] Figure 5 This is a diagram of the on-site blast hole sealing of the present invention.

[0035] Figure 6 This is a comparison diagram of the blasting block size in a mine sealing test in Yunnan Province, as shown in Embodiment 1 of the present invention; where (a) is unsealed and (b) is sealed with a sealing package.

[0036] Figure 7 This is a diagram of a half-hole sealing the sidewall of a mine in Yunnan Province, as shown in Embodiment 1 of the present invention.

[0037] Figure 8 This is a comparison chart of the average blasting advance in sealing a mine in Yunnan Province, as shown in Embodiment 1 of the present invention.

[0038] Figure 9 This is a comparison diagram of the blasting block size in a mine sealing test in Gansu Province, as shown in Embodiment 1 of the present invention; where (a, b) represent unsealed areas; and (c, d) represent sealed areas.

[0039] Figure 10 This is a comparative diagram of the layout of blast holes in a sealing test at a mine in Gansu Province, as shown in Embodiment 1 of the present invention. Detailed Implementation

[0040] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings, but the scope of protection of the present invention is not limited thereto; unless otherwise specified, all reagents used are commercially available analytical grade reagents, and all raw materials used can be purchased through conventional commercial channels, as shown in Table 1: Table 1 Main Components of the Rapid Hole Sealing Kit

[0041] In this invention, the parameters of the sealing bag aluminum foil can be customized according to the specific borehole size, as shown in Table 2: Table 2 Parameters of Aluminum Foil Bags Example 1

[0042] The rapid sealing kit for blast holes used in tunnel excavation, as described in this invention, has the following specific components: (1) Aluminum foil bag Specifically, it has a composite structure of at least three layers, from the inside out: a chemical-resistant polyethylene (PE) inner heat-sealing film, an intermediate aluminum foil barrier layer, and a high-strength polyester (PET) outer reinforcing film.

[0043] ① Inner layer polyethylene heat-sealing film (PE): Polyethylene (PE) is a thermoplastic resin obtained by polymerization of ethylene monomers.

[0044] ② Intermediate aluminum foil barrier layer (AL): Aluminum foil is an extremely thin sheet formed by rolling high-purity aluminum multiple times. It is an excellent heat conductor and light shield.

[0045] ③ Outer high-strength polyester film (PET): Polyethylene terephthalate (PET), commonly known as polyester, is an unsaturated polyester material composed of elements such as carbon, hydrogen, and oxygen. It is a thermoplastic polyester with the molecular formula (C... 10 H8O4) n .

[0046] This structure (PET / AL / PE) ensures extreme protection against moisture, air, and light, preventing isocyanate from absorbing moisture and deteriorating, and preventing foaming agent from evaporating, thus ensuring the long-term stability and activity consistency of the material under harsh storage conditions (shelf life of 6 months).

[0047] Before foaming, the aluminum foil bag is divided into cavity A and cavity B by a dividing tube in the middle, such as... Figure 3 As shown; cavity A is filled with component A, and cavity B is filled with component B. In this embodiment, the length of the aluminum film bag before foaming is 525mm and the width is 100mm.

[0048] (2) Component A packaging: The first aluminum foil bag encapsulates the black material system, the core of which is a high-functionality isocyanate group (-NCO) to ensure the formation of a rigid foam with a high cross-linking density, and a polymer of toluene diamine and propylene oxide as a modifier to enhance toughness, as detailed below: ① Core isocyanate: 80% high-functionality polymeric MDI (PMDI).

[0049] Main component selection: The black material system is based on polymethylene polyphenyl polyisocyanate (commonly known as polymeric MDI or crude MDI), and BASF M20S type polymeric MDI (BASF AG, M20S) is selected, with a -NCO mass fraction of 31.8% and an average functionality of about 2.9.

[0050] ②Key modifier: 20% of a polymer of toluene diamine and propylene oxide (TDA-EO polymer, CAS: 63641-63-4).

[0051] Chemical nature: This substance is a chain extender / crosslinker precursor containing amino or hydroxyl groups; it is prepared by an addition reaction between toluene diamine (TDA) and propylene oxide (PO), and the molecular chain retains the rigidity of the benzene ring while introducing the flexibility of the ether bond.

[0052] The total mass percentage of the isocyanate and modifier in component A is 100%.

[0053] (3) Component B packaging: a second aluminum foil bag encapsulating the white material system, composed of the following components by mass percentage: ① High-activity, high-hydroxyl-value polyol composition: 60%, providing abundant reactive hydroxyl groups to ensure rapid gelation and the formation of a high-strength polyurethane network molecular backbone; wherein, the high-activity polyether polyol is glycerol polyether, with a mass percentage of 50%; the high-functionality polyether polyol is sucrose polyether, with a mass percentage of 20%; the aromatic polyester polyol is phthalic anhydride polyester polyol, with a mass percentage of 20%; the amino polyether polyol is ethylenediamine polyether, with a mass percentage of 10%, and the total mass percentage of all substances is 100%.

[0054] ②Blowing agent: 20% cyclopentane, an organic compound with the chemical formula C5H 10 The molecular weight is 70.13, CAS Registry No. 287-92-3, EINECS Registry No. 206-016-6; the substance is a colorless and transparent liquid with a density of 0.751 g / cm³ and a boiling point of 49.2℃. Its foaming ratio and speed are specially designed to meet the filling requirements of different pore sizes.

[0055] ③ Composite catalyst system: 6%; among which, the high-efficiency gel catalyst is dimethylcyclohexylamine, with a mass percentage of 60%, which ensures the initial reaction rate in the sealing pack; the strong trimerizing catalyst is pentamethyldiethylenetriamine, with a mass percentage of 30%, which promotes the trimerization of isocyanate in the sealing pack to form stable isocyanurate rings, greatly improving the heat resistance, flame retardancy and compressive strength of the foam to withstand the high temperature and high pressure impact at the moment of explosion; the delayed equilibrium catalyst is 2-hydroxy-N,N,N-trimethyl-1-propylaminocarbamate, with a mass percentage of 10%, which controls the reaction rhythm, precisely controls the balance between foaming and gelation, and prevents "bulging" or internal cracking. The total mass percentage of all substances in the composite catalyst system is 100%.

[0056] ④ Foam stabilizer: 4%, which is polyether siloxane (Momentive, product batch number: Y-10762), used to stabilize the cell structure and form uniform and fine closed cells, which is the key to achieving high sealing performance and compressive strength. In the production of polyurethane foam (whether flexible, rigid, or semi-rigid), polyether siloxane is not an "optional" additive, but an essential key component. Its core role is to control and stabilize the foam structure, which directly determines the performance and quality of the final product. The EO content of polyether siloxane as a foam stabilizer is higher than that of ordinary polyether siloxane.

[0057] ⑤ Functional additives: 10%, including any proportion of halogen-free phosphate flame retardant (diphenyl phosphate, Wansheng Co., Ltd., CAS: 57583-54-7), and chopped glass fiber (China Jushi Co., Ltd., ECS13-3.0-988A, length 3mm), to further optimize the erosion and ablation resistance of the plug.

[0058] The total mass percentage of the polyol composition, foaming agent, composite catalyst system, foam stabilizer and functional additives in component B is 100%.

[0059] The mass ratio of component A to component B is 1:0.3, and the content of component A in the aluminum foil bag before foaming is 50 kg / m³. 3 The aluminum foil bags of component A and component B are arranged side by side and sealed together inside an outer protective bag with puncture-resistant and abrasion-resistant properties, forming a sealing package I.

[0060] In summary, Example 1 was conducted in a deep mine where the underground temperature is high. Therefore, cyclopentane (boiling point 49.2℃) was chosen as the foaming agent to ensure that the foaming effect occurs after the reaction is exothermic.

[0061] The sealing package I obtained in this embodiment was applied and tested in practice. The specific steps are as follows: (1) When drilling through holes, you may encounter loose stones, hole collapse, etc. In order to ensure that the sealing bag can be smoothly inserted into the hole when sealing the hole, it is recommended to blow out the loose stones in the hole with a sealing pipe or air pipe before sealing the hole.

[0062] (2) After the tape at the beginning of the divider strip is tied into the bag, starting from the first sealed bag on the side of the flower tube, remove the transparent tape at the front end of each divider strip; pinch the tape end with two fingers, rotate it in the opposite direction to remove it, and pull out the divider strip in the middle of the sealed bag.

[0063] (3) Knead for 10 seconds to mix component A and component B evenly. Quickly insert the sealed bag into the hole (5cm from the hole opening). After about 2 minutes, component A and component B will expand several times in volume through the polyurethane foaming reaction, resulting in a foamed body. The foamed body will expand the aluminum foil bag, resulting in a foamed aluminum foil bag as shown. Figure 4 As shown; the sealing bag expands inside the pore, and the material reacts within the bag and between the pore walls. The reaction liquid rapidly foams and expands inside the pore, tightly filling and adhering to the pore walls of the entire plugging section, forming a gapless sealing layer. After 10 minutes, the material completely solidifies, forming a high-strength, high-closed-cell rate polyurethane foam plugging body that is tightly bonded to the pore walls, as shown. Figure 5 As shown.

[0064] (4) Networked detonation: After all the borehole sealing bodies have solidified, the blasting network is connected and safety precautions are set up according to the design, and then the detonation is carried out.

[0065] The specific experimental results are as follows: Application 1: (1) Preliminary research Table 3. Statistical data of test results when the sealing package of this invention was not used in an underground tunneling project at a copper mine in Yunnan.

[0066] When using the existing blasting process in the mine without using the sealing package of this invention, the blasting parameters were statistically analyzed. The number of blasting holes was 49, of which 43 were charging holes. The average explosive charge was 108 kg, the hole depth was 3.3 m, the blasting advance was 2.6 m, and the hole utilization rate was 79%.

[0067] (2) Experiment 1: Implementation technical parameters: Without adjusting the layout of blast holes or the charging structure of the original blasting process in the mine, the rapid sealing package described in this invention is added.

[0068] Data statistics: The blasting parameters were collected and organized, including the usage of φ32 explosive coils, digital electronic detonators (5m), detonating cord, number of blast holes, and blasting advance.

[0069] Implementation period: Three parallel tests were conducted at the same blasting site.

[0070] The statistics are shown in the table below: Table 4. Statistical table of test data for mines with existing blasting technology unchanged and using sealing bags.

[0071] Using the existing blasting process in the mine and the sealing package of this invention, the blasting parameters were statistically analyzed. The average number of blasting holes was 52.3, of which 46.3 were charging holes. The average explosive charge was 110.7 kg, the hole depth was 3.18 m, the blasting advance was 3.0 m, and the hole utilization rate was 94.2%.

[0072] Compared to the case without the sealing pack, in Experiment 1, using the existing blasting process in the mine, the utilization rate of the blast holes increased from 79% to 94.2% simply by adding the rapid sealing pack of the present invention, which is a significant improvement.

[0073] (3) Experiment 2: Technical parameters implemented: Without adjusting the layout of the blast holes in the original blasting process of the mine, the amount of φ32 rolls of explosives was reduced, and the rapid sealing package described in this invention was used.

[0074] Data statistics: The blasting parameters were collected and organized, including the usage of φ32 explosive coils, digital electronic detonators (5m), detonating cord, number of blast holes, and blasting advance.

[0075] Implementation period: Two tests will be conducted at the same blasting site.

[0076] The statistics are shown in the table below: Table 5. Statistical table of experimental data on reducing the dosage of φ32 roll medicine.

[0077] Without adjusting the existing blasting process and borehole layout in the mine, the amount of φ32 rolls of explosive was reduced. After using the rapid sealing pack described in this invention, the blasting parameters were statistically analyzed. The average number of blasting boreholes was 52.5, of which 46.5 were charging holes. The average explosive charge was 100.5 kg, the borehole depth was 3.28 m, the blasting advance was 3.0 m, and the borehole utilization rate was 97.7%.

[0078] Compared to the case without the use of the sealing pack, in Experiment 2, the amount of φ32 rolls of explosives used in the original blasting process of the mine was reduced, and the rapid sealing pack for blast holes of the present invention was used. The utilization rate of blast holes increased from the original 79% to 97.7%, which is a significant effect. This shows that after using the sealing pack described in the present invention, the amount of explosives used can be effectively reduced, and the pollution caused by explosives to the environment can be reduced.

[0079] (4) Experiment 3: Rapid sealing test with increased borehole depth Implementation technical parameters: Without adjusting the layout of the blast holes in the original blasting process of the mine, the depth of the blast holes is increased, the charging structure is adjusted, and the rapid sealing package described in this invention is used.

[0080] Data statistics: The blasting parameters were collected and organized, including the usage of φ32 explosive coils, digital electronic detonators (5m), detonating cord, and blasting advance statistics.

[0081] Implementation cycle: The number of blasting operations at each blasting site is counted as 1.

[0082] The statistics are shown in the table below: Table 6. Statistical Table of Rapid Sealing Test Data with Increased Hole Depth

[0083] Summary: Through statistical analysis of the blasting sealing test (increasing the depth of the blast hole), the average number of blast holes was 53, of which 47 were charging holes, the average explosive charge was 144 kg, the blast hole depth was 3.95 m, the blasting advance was 3.6 m, and the blast hole utilization rate was 91.1%.

[0084] Increasing the borehole depth usually leads to a decrease in borehole utilization. However, after using the sealing pack of this invention, the borehole utilization rate increased significantly compared to the previous survey (low borehole depth, no sealing pack used). Although the amount of φ32 rolls of explosive used in the borehole also increased with the increase in borehole depth, simply increasing the amount of explosive without changing the charge structure often only exacerbates vibration, flyrock, and excessive crushing. The increase in borehole utilization rate from 79% to 91.1% is mainly attributed to the application of the sealing pack, which greatly improves the energy distribution and utilization of explosives, overcomes the rock mass clamping force, and controls the impact range of flyrock.

[0085] Regarding block size, unsealed blasting, such as Figure 6 As shown in (a), the proportion of large blocks in the blast pile is significantly increased, the forward thrust of the blast pile is long and the shape is "narrow and scattered", and energy dissipates in non-target directions. This is due to premature gas leakage leading to low energy utilization and incomplete rock mass loading. Using the plugging blasting method of this invention, as shown in (a), Figure 6 As shown in (b), the rock fragments in the blast pile are uniformly distributed with no obvious large pieces. The size of the fragments is concentrated, and the forward rushing distance of the blast pile is short. The pile shape is "wide and short", which reflects that the energy is concentrated on the target rock mass. This is because the high sealing performance of the expanding foam prolongs the action time of the blasting gas, and the energy is fully applied to the rock mass to break it up, reducing the energy dissipation.

[0086] Regarding the formation of tunnels, such as Figure 7 As shown, after using the plugging pack I to plug the hole, the utilization rate of blasting energy increased, the effect of blasting gas penetrating the fracture was fully utilized, the half-hole marks increased, and the tunnel formation effect was good.

[0087] The following results were achieved in this engineering experiment: (1) such as Figure 8 As shown, after applying the sealing package I obtained in Example 1, the average single-shot advance increased from 2.7m to 3.2m, representing a 9.52% increase in single-shot advance.

[0088] (2) Every 10 shots can reduce one cycle.

[0089] (3) Each shot increases the cost of plugging holes by about 280 yuan, saving 461.45 yuan in costs.

[0090] (4) The hole depth was increased to 3.7m, and the advance reached 3.4m.

[0091] (5) The blasted blocks after using the rapid sealing pack are uniform in size, with no obvious large blocks and concentrated blast piles.

[0092] (6) After using the quick-sealing pack, the blasting half hole marks are obvious and the outline is smooth.

[0093] This series of tests successfully verified the positive role of rapid plugging technology in downhole tunneling blasting and found an optimized solution that can improve efficiency and save costs, providing solid data support and directional guidance for subsequent large-scale applications.

[0094] Application 2: (1) Implementation background: A nickel mine in Gansu Province adopts the downward access backfilling mining method for mining operations. The mine is a low-grade ore mining area, which has high requirements for technical and economic indicators such as the utilization rate of blast holes. At the same time, in order to control the dilution rate and ensure the safety of mining operations, stricter standards are also put forward for the quality of roadway formation.

[0095] (2) Analysis method: This experiment adopted a combination of quantitative and qualitative analysis methods. By comparing key data indicators of different experimental groups, such as the degree of rock fragmentation, block size distribution and throwing distance, the direct effect and energy release characteristics of blasting were objectively measured. The blasting safety, technical economy and on-site operability were systematically evaluated to provide a comprehensive basis for the selection of the scheme. All analyses were carried out under the premise of consistent geological conditions to ensure the scientific nature of the comparison and the reliability of the conclusions.

[0096] (3) Test results: Regarding block size, in blasting without effective orifice sealing, the results are as follows Figure 9 As shown in (a) and (b), the blast pile exhibits characteristics of high bulk density, long forward thrust, and scattered shape, with a large amount of energy dissipating in non-target directions; in contrast, the blasting method using this invention for sealing results in the following... Figure 9 As shown in (c, d), the explosive piles are uniformly concentrated with no obvious large blocks, the forward thrust is short, and the pile shape is more compact, indicating that the energy is effectively concentrated and utilized.

[0097] Regarding the utilization rate of blast holes, two groups were set up: an unsealed group and a sealed group in this embodiment. Five different roadways were selected, and after testing, the average utilization rate of blast holes increased by 6.02% (as shown in Table 7).

[0098] Table 7 Results of borehole utilization test

[0099] In terms of economic benefits, the arrangement of boreholes without plugging and with plugging according to the present invention is as follows: Figure 10 As shown, the hole-plugging arrangement of the present invention reduces the number of charging holes by 9 per section compared to the unplugged arrangement, resulting in a saving of 1130.25 yuan per blast in material costs, labor costs, rock drilling costs, etc. (as shown in Table 8). Table 8 Cost Comparison Example 2

[0100] The rapid sealing package for blast holes in tunnel excavation, as described in this invention, mainly consists of an aluminum foil bag, a component A package, and a component B package. Its specific components are as follows: (1) Aluminum foil bag: from the inside out, it consists of: a chemical-resistant polyethylene (PE) inner heat-sealing film, an aluminum foil barrier layer in the middle, and a high-strength polyester (PET) outer reinforcing film; the length of the aluminum foil bag before foaming is 250mm and the width is 40mm.

[0101] (2) Packaging of Component A: ① The core isocyanate is high-functionality polymeric MDI (PMDI), with a mass percentage of 85%. The black material system is mainly composed of polymethylene polyphenyl polyisocyanate, and PM-200 type polymeric MDI (Wanhua Chemical Group, product brand: WANNATE®PM-200) is selected, with a -NCO mass fraction of 31.5% and an average functionality of 2.7.

[0102] ②The key modifier is a polymer of toluene diamine and propylene oxide, with a mass percentage of 15%.

[0103] The total mass percentage of the isocyanate and modifier in component A is 100%.

[0104] (3) Component B packaging: a second aluminum foil bag encapsulating the white material system, composed of the following components by mass percentage: ① High-activity, high-hydroxyl-value polyether polyol composition: 75%; specifically includes: The highly active polyether polyol is glycerol polyether, with a mass percentage of 30%; the high-functionality polyether polyol is sucrose polyether, with a mass percentage of 40%; the aromatic polyester polyol is phthalic anhydride polyester polyol, with a mass percentage of 25%; the amino polyether polyol is ethylenediamine polyether, with a mass percentage of 5%, and the total mass percentage of all substances is 100%.

[0105] ② Foaming agent: 18% n-pentane, an organic compound with the chemical formula C5H 12 It has a molecular weight of 72.15, CAS Registry No. 109-66-0, and EINECS Registry No. 203-692-4; it belongs to the aliphatic saturated hydrocarbon organic compound, and is a colorless transparent liquid with a faint minty aroma. Its density is 0.626 g / cm³, and its boiling point is 36.1℃.

[0106] ③ Composite catalyst system: 3%, specifically including: the high-efficiency gel catalyst is N,N-dimethylbenzylamine, with a mass percentage of 55%; the strong trimerizing catalyst is 1,3,5-tris(dimethylaminopropyl)-1,3,5-hexahydrotriazine, with a mass percentage of 40%; the delayed equilibrium catalyst is 2-hydroxy-N,N,N-trimethyl-1-propylaminocarbamate, with a mass percentage of 5%; the total mass percentage of all substances in the composite catalyst system is 100%.

[0107] ④ The foam stabilizer is polyether siloxane, with a mass percentage of 4%.

[0108] ⑤ The mass percentage of functional additives is 0%.

[0109] The total mass percentage of the polyol composition, foaming agent, composite catalyst system, foam stabilizer and functional additives in component B is 100%.

[0110] The mass ratio of component A to component B is 1:1.2, and the content of component A in the aluminum foil bag before foaming is 10 kg / m³. 3 The aluminum foil bags of component A and component B are arranged side by side and sealed together inside an outer protective bag with puncture-resistant and abrasion-resistant properties, forming a sealing package II.

[0111] When using the sealing pack II, the kneading time is 15 seconds.

[0112] Example 2's sealing pack II is a rapidly curing, high-strength, and high-crosslinking-density polyurethane sealing material based on high-functionality isocyanate and high-hydroxyl-value polyether. It achieves rapid reaction and shaping through an aggressive catalyst system, generating a foam with a rigid closed-cell structure. It has excellent compressive strength, dimensional stability, and rapid sealing ability, making it particularly suitable for engineering scenarios that require rapid establishment of high-strength support and sealing. However, its flexibility is relatively insufficient, and it has extremely strict requirements for operational timeliness. It is suitable for sealing environments in mines where the temperature does not exceed 35°C. Example 3

[0113] The rapid sealing package for blast holes in tunnel excavation, as described in this invention, mainly consists of an aluminum foil bag, a component A package, and a component B package. Its specific components are as follows: (1) Aluminum foil bag: from the inside out, it consists of: a chemical-resistant polyethylene (PE) inner heat-sealing film, an aluminum foil barrier layer in the middle, and a high-strength polyester (PET) outer reinforcing film; the length of the aluminum foil bag before foaming is 800mm and the width is 165mm.

[0114] (2) Packaging of Component A: ① The core isocyanate is high-functionality polymeric MDI (PMDI), with a mass percentage of 90%; it is mainly composed of polymethylene polyphenyl polyisocyanate, with a -NCO mass fraction of 32%; PMDI is a mixture of isocyanates with an average functionality of 3.0, and its molecular structure contains a large number of benzene rings and methylene groups.

[0115] ②The key modifier is a polymer of toluene diamine and propylene oxide, with a mass percentage of 10%.

[0116] (3) Component B packaging: a second aluminum foil bag encapsulating the white material system, composed of the following components by mass percentage: ① High-activity, high-hydroxyl-value polyether polyol composition: 73%; specifically includes: The highly active polyether polyol is glycerol polyether, with a mass percentage of 45%; the high-functionality polyether polyol is sucrose polyether, with a mass percentage of 30%; the aromatic polyester polyol is phthalic anhydride polyester polyol, with a mass percentage of 10%; the amino polyether polyol is ethylenediamine polyether, with a mass percentage of 15%; and the total mass percentage of all substances in the polyol composition is 100%.

[0117] ② Foaming agent: 10% isopentane, an organic compound with the chemical formula C5H 12 The substance has a molecular weight of 72.15, CAS Registry Number 78-78-4, and EINECS Registry Number 201-142-8; it is a colorless, transparent liquid with a density of 0.62 g / cm³. 3 Boiling point 27.8℃.

[0118] ③ Composite catalyst system: 6%; wherein the high-efficiency gel catalyst is N,N-dimethylbenzylamine, with a mass percentage of 50%; the strong trimerizing catalyst is tris(dimethylaminopropyl)hexahydrotriazine, with a mass percentage of 35%; the delayed equilibrium catalyst is 2-hydroxy-N,N,N-trimethyl-1-propylcarbamate, with a mass percentage of 15%; the total mass percentage of all substances in the composite catalyst system is 100%.

[0119] ④ The foam stabilizer is polyether siloxane, with a mass percentage of 1%.

[0120] ⑤ The functional additives account for 10% by mass, including any proportion of halogen-free phosphate flame retardant (diphenyl phosphate, Wansheng Co., Ltd., CAS: 57583-54-7), reinforcing filler chopped glass fiber (China Jushi Co., Ltd., ECS13-3.0-988A), and toughening agent hydroxyl-terminated polybutadiene liquid rubber (Evonik Industries, Polyvest HT).

[0121] The total mass percentage of the polyol composition, foaming agent, composite catalyst system, foam stabilizer and functional additives in component B is 100%.

[0122] The mass ratio of component A to component B is 1:2, and the content of component A in the aluminum foil bag before foaming is 100 kg / m³. 3 .

[0123] The remaining steps are the same as in Example 1, forming a sealing package III.

[0124] When using the sealing pack III, the kneading time is 20 seconds.

[0125] Blocking Pack III can be used in various scenarios, such as: ① Deep hole, large diameter pre-splitting blasting or smooth blasting: The sealing and anti-explosion properties of the plug are extremely important to control the blasting profile.

[0126] ② High-power blasting in hard rock strata: The explosive impact pressure is large, requiring the sealing body to have extremely high compressive strength.

[0127] ③ Special projects that require precise control of blasting energy: such as vibration reduction blasting in urban tunnels and blasting near important facilities. The reliability of the sealing body is directly related to the blasting effect and safety.

[0128] Applying the sealing package III from Example 3 to borehole sealing provides a solution that is almost at the level of an "engineering structural component." Its core value lies in its unparalleled compressive strength and sealing reliability. It is particularly suitable for critical blasting scenarios where the requirements for combating the "sealing body rupture" problem are the most stringent and the requirements for blasting energy utilization are the highest. However, when applying it, its cost, requirements for construction equipment and processes must be considered, and its filling and compaction capabilities under specific borehole conditions must be evaluated. Example 4

[0129] The rapid sealing package for blast holes in tunnel excavation, as described in this invention, mainly consists of an aluminum foil bag, a component A package, and a component B package. Its specific components are as follows: (1) Aluminum foil bag: Same as in Example 1.

[0130] (2) Packaging of Component A: ① Core isocyanate: It is a high-functionality polymeric MDI (PMDI) with a mass percentage of 95%, mainly composed of polymethylene polyphenyl polyisocyanate, with a -NCO mass fraction of 30%; PMDI is a mixture of isocyanates with an average functionality of 2.5, and its molecular structure contains a large number of benzene rings and methylene groups.

[0131] ②The key modifier is a polymer of toluene diamine and propylene oxide, with a mass percentage of 5%.

[0132] The total mass percentage of the isocyanate and modifier in component A is 100%.

[0133] (3) Component B packaging: a second aluminum foil bag encapsulating the white material system, composed of the following components by mass percentage: ① High-activity, high-hydroxyl-value polyether polyol composition: 67%, specifically including: The highly active polyether polyol is glycerol polyether, with a mass percentage of 40%; the high-functionality polyether polyol is sucrose polyether, with a mass percentage of 20%; the aromatic polyester polyol is phthalic anhydride polyester polyol, with a mass percentage of 30%; the amino polyether polyol is ethylenediamine polyether, with a mass percentage of 10%, and the total mass percentage of all substances is 100%.

[0134] ② Foaming agent: 15%, of which cyclopentane is 50% and n-pentane is 50%.

[0135] ③ Composite catalyst system: 5%, of which the high-efficiency gel catalyst is dimethylcyclohexylamine, with a mass percentage of 65%; the strong trimerizing catalyst is pentamethyldiethylenetriamine, with a mass percentage of 30%; the delayed equilibrium catalyst is 2-hydroxy-N,N,N-trimethyl-1-propylcarbamate, with a mass percentage of 5%; the total mass percentage of all substances in the composite catalyst system is 100%.

[0136] ④ The foam stabilizer is polyether siloxane, with a mass percentage of 3%.

[0137] ⑤ The functional additives account for 10% by mass, including any proportion of halogen-free phosphate flame retardants, chopped glass fiber reinforced fillers, and toughening agents such as hydroxyl-terminated polybutadiene liquid rubber.

[0138] The total mass percentage of the polyol composition, foaming agent, composite catalyst system, foam stabilizer and functional additives in component B is 100%.

[0139] The mass ratio of component A to component B is 1:2, and the content of component A in the aluminum foil bag before foaming is 100 kg / m³. 3 .

[0140] The remaining steps are the same as in Example 1, forming a sealing package IV.

[0141] Example 4's borehole plugging pack IV is a multifunctional, high-performance plugging material with a composite reinforcement design. While maintaining the rapid reaction and high cross-linking density of high-hydroxyl polyether polyol, it innovatively introduces up to 10% functional additives (which may include flame retardants, chopped glass fibers, and other reinforcing fillers and toughening agents). This not only gives it excellent rapid curing and sealing performance, but also significantly improves its mechanical strength, impact toughness, and flame retardant safety. In borehole plugging applications, this material can fill the borehole wall cracks with its good foaming properties, and form a high-strength, anti-explosion, and tight plugging body by relying on the reinforcing components. At the same time, its flame retardant properties are particularly suitable for mine blasting in hazardous environments such as those containing gas. Therefore, plugging pack IV is very suitable for deep-hole blasting, hard rock blasting, and blasting engineering scenarios with high requirements for plugging strength, safety, and comprehensive performance, as well as complex safety conditions. Example 5

[0142] The rapid sealing package for blast holes in tunnel excavation, as described in this invention, mainly consists of an aluminum foil bag, a component A package, and a component B package. Its specific components are as follows: (1) Aluminum foil bag: Same as in Example 1.

[0143] (2) Packaging of Component A: ①The core isocyanate is high-functionality polymeric MDI (PMDI), with a mass percentage of 80%, mainly composed of polymethylene polyphenyl polyisocyanate, and its -NCO mass fraction is 30%; PMDI is a mixture of isocyanates with an average functionality of 2.5, and its molecular structure contains a large number of benzene rings and methylene groups.

[0144] ②The key modifier is a polymer of toluene diamine and propylene oxide, with a mass percentage of 20%.

[0145] The total mass percentage of the isocyanate and modifier in component A is 100%.

[0146] (3) Component B packaging: a second aluminum foil bag encapsulating the white material system, composed of the following components by mass percentage: ① High-activity, high-hydroxyl-value polyether polyol composition: 75%, specifically including: 50% by mass of glycerol polyether, 20% by mass of sucrose polyether, 20% by mass of phthalic anhydride polyester polyol, 20% by mass of phthalic anhydride polyester polyol, and 10% by mass of ethylenediamine polyether polyol, with a total mass percentage of 100%.

[0147] ② Foaming agent: 15%, of which n-pentane is 50% and isopentane is 50%.

[0148] ③ Composite catalyst system: 4%, specifically including: the high-efficiency gel catalyst is dimethylcyclohexylamine, with a mass percentage of 55%; the strong trimerizing catalyst is pentamethyldiethylenetriamine, with a mass percentage of 40%; the delayed equilibrium catalyst is 2-hydroxy-N,N,N-trimethyl-1-propylcarbamate, with a mass percentage of 5%; the total mass percentage of all substances in the composite catalyst system is 100%.

[0149] ④ The foam stabilizer is polyether siloxane, with a mass percentage of 1%.

[0150] ⑤ The functional additives account for 5% by weight, including any proportion of halogen-free phosphate flame retardants, chopped glass fiber reinforced fillers, and toughening agents such as hydroxyl-terminated polybutadiene liquid rubber.

[0151] The total mass percentage of the polyol composition, foaming agent, composite catalyst system, foam stabilizer and functional additives in component B is 100%.

[0152] The mass ratio of component A to component B is 1:2, and the content of component A in the aluminum foil bag before foaming is 100 kg / m³. 3 .

[0153] The remaining steps are the same as in Example 1, forming a sealing package V.

[0154] The borehole plugging kit in Example 5 is a general-purpose plugging material that balances rapid response, good foaming performance, and enhanced basic functionality. Its formulation maintains a high polyether polyol content (75%) and a moderate foaming agent content (15%), ensuring good reactivity, high foaming rate, and filling capacity. It also retains 5% functional additives to provide customizable flame-retardant, reinforced, or toughened bases. In borehole plugging applications, this material can rapidly foam and fill boreholes, forming a plug with a certain strength and sealing performance. Its balance between reaction speed and foaming characteristics makes it suitable for conventional blasting operations, exhibiting good applicability and cost-effectiveness. It is particularly suitable for medium-condition blasting projects that require a certain level of plugging speed, filling density, and basic functionality, but do not require extremely high strength or special performance.

[0155] Based on the above embodiments, the performance and applicable scenarios of each borehole sealing package are shown in the table below:

[0156] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A rapid hole sealing kit for tunnel excavation, characterized in that, The rapid borehole sealing package is a double-chamber integrated bag composed of three layers of composite aluminum foil bags. One chamber of the double-chamber integrated bag contains component A, which includes 80%-95% isocyanate and 5%-20% modifier by mass percentage. The other chamber contains component B, which includes 60%-75% polyol, 10%-20% foaming agent, 3%-6% catalyst, 1%-4% foam stabilizer and 0%-10% functional additives by mass percentage.

2. The rapid hole sealing kit for tunnel excavation according to claim 1, characterized in that... The three-layer composite aluminum foil bag is composed of polyethylene, aluminum foil and polyester film.

3. A rapid hole sealing kit for tunnel excavation according to claim 1, characterized in that... The mass ratio of component A to component B is 1:(0.3-2).

4. A rapid hole sealing kit for tunnel excavation according to claim 1, characterized in that... The modifier in component A is a polymer of toluene diamine and propylene oxide.

5. A rapid hole sealing kit for tunnel excavation according to claim 1, characterized in that: The polyol is composed of highly reactive polyether polyol, high-functionality polyether polyol, aromatic polyester polyol and amine polyether polyol, and meets the following mass ratio: highly reactive polyether polyol: 30%-50%, high-functionality polyether polyol: 20%-40%, aromatic polyester polyol: 10%-30%, amine polyether polyol: 5%-15%, wherein the hydroxyl value of the polyol is ≥300mgKOH / g.

6. A rapid hole sealing kit for tunnel excavation according to claim 1, characterized in that: The foaming agent is selected from one or more of cyclopentane, n-pentane, and isopentane, in any proportion.

7. A rapid hole sealing kit for tunnel excavation according to claim 1, characterized in that: The catalyst comprises, by mass percentage, 40%-65% gel catalyst, 30%-55% trimerizing catalyst, and 5-15% delayed equilibrium catalyst; wherein the gel catalyst comprises one of dimethylcyclohexylamine and N,N-dimethylbenzylamine, the trimerizing catalyst comprises one of pentamethyldiethylenetriamine and 1,3,5-tris(dimethylaminopropyl)-1,3,5-hexahydrotriazine, and the delayed equilibrium catalyst is 2-hydroxy-N,N,N-trimethyl-1-propylaminocarbamate.

8. A rapid hole sealing kit for tunnel excavation according to claim 1, characterized in that: The foam stabilizer is polyether siloxane.

9. A rapid hole sealing kit for tunnel excavation according to claim 1, characterized in that: The functional additives include one or more of flame retardants, reinforcing fillers, or toughening agents, in any proportion.

10. The application of the rapid borehole sealing kit according to any one of claims 1-9, characterized in that... The specific steps are as follows: clean the blast hole, fully mix components A and B in the blast hole rapid sealing package, and then insert it into the predetermined position in the blast hole.

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