Grouting reinforcement method for soft bottom area of steeply inclined complex structure coal seam
Through detailed analysis of soft bottom geology of the coal seam complex structure and reasonable setting of grouting holes, combined with the use of inorganic composite materials, the waste of materials and unreasonable engineering caused by inaccurate position of the reinforcement layer in traditional grouting and reinforcement methods is solved. , achieving improvements in the stability and safety of coal seams.
Patent Information
- Application Number
- CN202411632145.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-15
- Publication Date
- 2025-01-03
AI Technical Summary
In the soft bottom area of the coal seam with sharp inclined complex structure, the traditional grouting reinforcement method is prone to the location of the reinforcement layer too close or too far away from the coal seam, resulting in waste of slurry running and unreasonable drilling projects, affecting the reinforcement effect.
By analyzing the soft bottom geology of the coal seam in a complex structure with acute incline, setting equally spaced grouting holes, and selecting appropriate grouting materials and depths based on geological structure and material characteristics, using inorganic composite materials such as HWI-reinforcement materials or AKML- 70 Inorganic anchor material is reinforced, and the grouting pressure is monitored and controlled in real time to ensure the sealing and cleaning of grouting holes.
It effectively avoids the problem of too deep or too shallow grouting holes, improves the reinforcement strength of grouting holes, reduces material waste, improves the stability and safety of coal seams, and achieves economic and reasonable reinforcement effects.
Smart Images
Figure CN119244277A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of grouting reinforcement, in particular to a grouting reinforcement method for a soft bottom area of a steeply inclined complex structure coal seam. Background Art
[0002] The grouting reinforcement method for the soft bottom area of steeply inclined and complexly structured coal seams mainly involves injecting polymer chemical coal rock reinforcement agents into the broken rock strata of the coal seams. These reinforcement agents are used to bond the cracks together to achieve the purpose of reinforcement. This method is particularly suitable for the soft bottom areas of steeply inclined and complexly structured coal seams, because these areas are usually threatened by Ordovician limestone water, the coal seams have low compressive strength, are easily broken and deformed, and are prone to cracks and larger fault zones. By injecting polymer chemical coal rock reinforcement agents, the cracks can be bonded together, and the materials injected into the slurry can be strongly locked together to prevent relative movement between the locked rock blocks, ultimately achieving the purpose of coal rock reinforcement.
[0003] The grouting reinforcement method for the soft bottom area of steeply inclined and complex coal seams mainly involves the following steps and technologies: Development of drilling sites in coal seam tunnels at the working face: First, a hole is drilled in the coal seam, and the direction of the hole is pointed to the aquifer and aquifer of the coal seam floor. This step is to create a working space suitable for grouting reinforcement in the coal seam tunnel; Drilling construction: Using rotary drilling technology, after a certain depth below the coal seam floor, the drill is lifted, the hole is expanded, and a first-level sealing casing is installed for grouting and sealing. This step is to create the drill holes required for reinforcement in the coal seam floor; Grouting reinforcement: By injecting polymer chemical coal rock reinforcement agents, cracks and cracks are bonded together to enhance the stability and safety of the coal seam. This reinforcement agent can be polyurethane, epoxy resin, acrylamide Types, acrylates, urea-formaldehyde resins, etc. The specific selection depends on the characteristics of the coal seam and the reinforcement requirements; Pressure test: After the primary casing and the secondary casing are fixed, a pressure test is carried out to ensure the quality and effectiveness of grouting and sealing, which is to ensure that the effect of grouting reinforcement can be durable and reliable; Directional drilling construction: After the pressure test is passed, PDC drill bits are used for directional drilling to form a borehole. During the drilling process, the drilling direction is adjusted according to the measured parameters and the geological data obtained, so that the borehole extends along the predetermined reinforcement layer according to the designed trajectory, and finally a borehole for grouting reinforcement is formed. Through the above steps, the stability and safety problems in the soft bottom area of the steeply inclined and complex structure coal seam can be effectively solved, and the safe mining conditions of the coal seam can be improved.
[0004] However, traditional grouting reinforcement has the following disadvantages: In traditional grouting reinforcement, each reinforcement point has the same depth, but the situation in the soft bottom area of the coal seam is complicated, and it is easy for the reinforcement layer to be too close to the coal seam. During the grouting process, a large amount of grouting may occur, wasting grouting materials and failing to achieve the purpose of reinforcement. Or the grouting layer is too far away from the coal seam, the drilling project is large, and the technical and economic issues are unreasonable, which affects the reinforcement effect. Summary of the invention
[0005] The purpose of the present invention is to provide a grouting reinforcement method for the soft bottom area of a steeply inclined and complexly structured coal seam, so as to solve the problem that in the traditional grouting reinforcement proposed in the above background technology, the depth of each reinforcement point is the same, but the situation in the soft bottom area of the coal seam is complicated, and it is easy for the reinforcement layer to be too close to the coal seam. During the grouting process, a large amount of grouting may occur, wasting grouting materials, and the purpose of reinforcement cannot be achieved; or the grouting position layer is too far away from the coal seam, the drilling project is large, and the technical and economic issues are unreasonable, which affects the reinforcement effect.
[0006] To achieve the above object, the present invention provides the following technical solution: a grouting reinforcement method for the soft bottom area of a steeply inclined complex structure coal seam, comprising the following steps: Step 1: Geological analysis: Analyze the soft bottom geology of the steeply inclined complex structure coal seam in the grouting reinforcement area; Step 2: Setting the grouting holes: Setting the positions and depths of the grouting holes according to the geological analysis materials in step 1; Step 3: Determine the grouting material: select the grouting material to be placed in the grouting hole according to the reinforcement hardness requirements; Step 4: Prepare grouting material: prepare the selected grouting material and store it in a grouting tank; Step 5: Sealing the grouting hole: After cleaning the impurities in the grouting hole, insert the grouting pipe into the grouting hole and seal the gap between the grouting pipe and the grouting hole; Step 6: Material grouting: connect the grouting tank to the pump body, connect the pump body to the grouting pipe, and the pump body extracts the grouting material in the grouting tank and transports it to the grouting hole through the grouting pipe; Step 7: Clean the pipeline: The pressure sensor senses the pressure in the grouting hole in real time. When the set pressure value is reached, the grouting pipe is withdrawn and cleaned with cleaning equipment.
[0007] As a preferred technical solution of the present invention, the geological analysis in step 1 specifically includes the geological structure of the coal seam, the thickness of the coal seam, the inclination of the coal seam and the complexity of the geological structure.
[0008] As a preferred technical solution of the present invention, the positions of the grouting holes in the step 2 are specifically three grouting holes are set in a single plane, and the three grouting holes are arranged at equal intervals, and the equal intervals are greater than or equal to 500 mm.
[0009] As a preferred technical solution of the present invention, the depth of the grouting hole is specifically set by theoretical calculation method, tunnel observation method and borehole perspective method. The calculation formula of the theoretical calculation method is as follows: depth = rock layer depth - drainage depth - borehole length - grouting agent height difference. The tunnel observation method is determined according to the purpose of grouting, geological conditions and grouting material factors. The borehole perspective method drills two holes at a suitable location like the coal seam floor, places an infinite transmitter in one hole, and places a receiver in the other hole. Radio waves are attenuated to varying degrees when propagating in different media or in a damaged homogeneous body, and the magnitude of the attenuation is determined by the resistivity of the medium.
[0010] As a preferred technical solution of the present invention, the grouting material determined in step three is specifically as follows: the first category is inorganic materials, mainly cement-based materials, such as cement, gypsum and various high-water materials, which do not produce chemical reactions when used; the second category is organic polymer materials, which are mainly polyurethane or other resin materials, which produce reaction heat of more than 120°C when used; the third category is inorganic composite materials.
[0011] As a preferred technical solution of the present invention, the inorganic composite material is specifically HWI-reinforcement material and AKML-70 inorganic anchoring material, and the HWI-reinforcement material is a composite grouting reinforcement material composed of inorganic ultrafine powder.
[0012] As a preferred technical solution of the present invention, the sealing in step five is specifically to seal the grouting hole at the designated position of the grouting pipe by wrapping hemp rope and covering it with epoxy resin material.
[0013] As a preferred technical solution of the present invention, the pressure value set in step seven is specifically a grouting final pressure of 5.0 MPa.
[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: by analyzing the geological information of the soft bottom area of the steeply inclined and complex structure coal seam, the depth of the grouting hole is calculated and set, thereby avoiding the phenomenon of the grouting hole being too deep or too shallow, and reinforcing the grouting hole by HWI-reinforcement material or AKML-70 inorganic anchoring material, thereby improving the reinforcement strength of the grouting hole and meeting people's usage needs. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Figure 1 It is a flow chart of the present invention. DETAILED DESCRIPTION
[0016] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.
[0017] See also Figure 1 The present invention provides a grouting reinforcement method for the soft bottom area of a steeply inclined complex structure coal seam, comprising the following steps: Step 1: Geological analysis: Analyze the soft bottom geology of the steeply inclined complex structure coal seam in the grouting reinforcement area; Step 2: Setting the grouting holes: Setting the positions and depths of the grouting holes according to the geological analysis materials in step 1; Step 3: Determine the grouting material: select the grouting material to be placed in the grouting hole according to the reinforcement hardness requirements; Step 4: Prepare grouting material: prepare the selected grouting material and store it in a grouting tank; Step 5: Sealing the grouting hole: After cleaning the impurities in the grouting hole, insert the grouting pipe into the grouting hole and seal the gap between the grouting pipe and the grouting hole; Step 6: Material grouting: connect the grouting tank to the pump body, connect the pump body to the grouting pipe, and the pump body extracts the grouting material in the grouting tank and transports it to the grouting hole through the grouting pipe; Step 7: Clean the pipeline: The pressure sensor senses the pressure in the grouting hole in real time. When the set pressure value is reached, the grouting pipe is withdrawn and cleaned with cleaning equipment.
[0018] The geological analysis in step one specifically includes the geological structure of the coal seam, the thickness of the coal seam, the inclination of the coal seam and the complexity of the geological structure.
[0019] The positions of the grouting holes in step 2 are specifically to set three grouting holes in a single plane, and the three grouting holes are set at equal intervals, and the equal intervals are greater than or equal to 500 mm.
[0020] The depth of the grouting hole is specifically set through theoretical calculation method, tunnel observation method and borehole perspective method. The calculation formula of the theoretical calculation method is as follows: Depth = rock layer depth - drainage depth - borehole length - grouting agent height difference. The tunnel observation method is determined according to the purpose of grouting, geological conditions and grouting material factors. The borehole perspective method drills two holes at a suitable location like the coal seam floor, places an infinite transmitter in one hole and a receiver in the other hole. Radio waves are attenuated to varying degrees when propagating in different media or in a damaged homogeneous body. The magnitude of the attenuation is determined by the resistivity of the medium.
[0021] The grouting materials determined in step three are specifically classified into the following categories: the first category is inorganic materials, mainly cement-based materials, such as cement, gypsum and various high-water materials, which do not produce chemical reactions when used; the second category is organic polymer materials, which are mainly polyurethane or other resin materials, which produce reaction heat of more than 120°C when used; the third category is inorganic composite materials.
[0022] The inorganic composite materials are specifically HWI-reinforcement materials and AKML-70 inorganic anchoring materials. The HWI-reinforcement materials are composite grouting reinforcement materials composed of inorganic ultrafine powders.
[0023] The sealing in step five is specifically to seal the grouting hole by wrapping hemp rope and covering it with epoxy resin material on the outside of the designated position of the grouting pipe.
[0024] The pressure value set in step seven is specifically 5.0 MPa as the final grouting pressure.
[0025] Embodiment 1: In the present invention, the soft bottom geology of the steeply inclined complex structure coal seam in the grouting reinforcement area is analyzed; the position and depth of the grouting hole are set according to the geological analysis material; three grouting holes are set in a single plane, and the three grouting holes are set at equal intervals, and the equal intervals are greater than or equal to 500mm. The depth of the grouting hole is specifically set by theoretical calculation method, tunnel observation method and borehole perspective method. The calculation formula of the theoretical calculation method is as follows: depth = rock layer depth-drainage depth-borehole length-grouting agent height difference. The tunnel observation method is determined according to the purpose of grouting, geological conditions and grouting material factors. The borehole perspective method drills two holes in the coal seam floor at a suitable position, places an infinite transmitter in one hole, and places a receiver in the other hole. Radio waves are attenuated to varying degrees when propagating in different media or in a damaged homogeneous body. The magnitude of the attenuation is determined by the resistivity of the medium. The angle of the grouting hole is greater than 5° of the coal seam inclination. , according to the requirement of reinforcement hardness, the grouting material to be placed in the grouting hole is selected, and the selected material is HWI-reinforcement material grouting. First, the slurry is prepared according to the water-cement ratio of 1:0.4-1, and then the grouting equipment is used to inject it into the cracks of the broken coal rock mass through the grouting borehole under high pressure. Under the action of high pressure, the slurry penetrates and expands in the reinforced stratum, and then a series of physical and chemical reactions are generated to generate a network skeleton of a consolidated body that has strong adhesion to the broken coal rock mass and fills the entire crack, thereby reinforcing and filling the reinforced stratum. After cleaning the impurities in the grouting hole, the grouting pipe is inserted into the grouting hole, and the gap between the grouting pipe and the grouting hole is sealed; the grouting tank is connected to the pump body, the pump body is connected to the grouting pipe, the pump body extracts the grouting material in the grouting tank and transports it to the grouting hole through the grouting pipe; the pressure sensor senses the pressure in the grouting hole in real time, and the grouting pipe is withdrawn when the set pressure value is reached, and the grouting pipe is cleaned using a cleaning device.
[0026] Embodiment 2: In the present invention, the soft bottom geology of the steeply inclined complex structure coal seam in the grouting reinforcement area is analyzed; the position and depth of the grouting hole are set according to the geological analysis material; three grouting holes are set in a single plane, and the three grouting holes are set at equal intervals, and the equal intervals are greater than or equal to 500mm. The depth of the grouting hole is specifically set by theoretical calculation method, tunnel observation method and borehole perspective method. The calculation formula of the theoretical calculation method is as follows: depth = rock layer depth - drainage depth - borehole length - grouting agent height difference, and the tunnel observation method is determined according to the purpose of grouting, geological conditions and grouting material factors. The drilling perspective method is to drill two holes at a suitable location like the coal seam floor, place an infinite transmitter in one hole, and place a receiver in the other hole. When radio waves propagate in different media or in a damaged homogeneous body, they are attenuated to varying degrees. The magnitude of the attenuation depends on the resistivity of the medium. The angle of the grouting hole is greater than the coal seam inclination angle of 5°. The grouting material is selected according to the reinforcement hardness requirements. The selected material is AKML-70 inorganic anchoring material grouting. After adding an appropriate amount of water to the grouting bucket, the required amount of anchoring material is added in turn, and stirring is performed while adding. After complete addition, a high-torque stirrer must be used to stir quickly for at least 10 minutes. n or more. During the grouting process, a low-speed agitator is used to stir to prevent solidification. According to different tunnel environments and different support conditions of the coal seam, the appropriate water-cement ratio is determined. Usually, the water-cement ratio of the grouting material is 0.25-0.35. After the anchoring material is fully stirred, special grouting equipment must be used for grouting construction. The grouting pressure is not less than 7MPa, and the grouting pressure is controlled within a certain range, usually 5-9MPa. Different foundation conditions require different grouting pressures. After the grouting is completed, the grouting nut is installed to prevent the slurry from flowing back and the equipment is cleaned in time. After cleaning the impurities in the grouting hole, the grouting pipe is inserted into the grouting hole, and the gap between the grouting pipe and the grouting hole is sealed; the grouting tank is connected to the pump body, the pump body is connected to the grouting pipe, the pump body extracts the grouting material in the grouting tank and transports it to the grouting hole through the grouting pipe; the pressure sensor senses the pressure in the grouting hole in real time, and the grouting pipe is withdrawn when the set pressure value is reached, and the grouting pipe is cleaned using a cleaning device.
[0027] In order to verify the actual application effect of anchor-grouting support, the scheme effect was evaluated by surface displacement observation, deep base point monitoring, roof drilling and surrounding rock loosening zone detection methods. The results showed that the roof subsidence of the 6 measuring points with uninterrupted surface displacement monitoring at 70 m in front of the working face was 37-47 mm, with an average of 41.8 mm; the side convergence of the 6 measuring points was 25-43 mm, most of which were 43-59 mm, with an average of 51.2 mm. With the mining of the working face, the displacement of the surrounding area increased sharply within 30 m ahead of the working face. The maximum deformation was 24.6 mm in the tunnel area, the average deformation of 3-6 m deep was only 5 mm, and the loosening zone of the tunnel side was only 1.2 m. The stability of the tunnel surrounding rock was good, and there was no surrounding rock instability. At this stage, the grouting reinforcement in the soft bottom area of the steeply inclined complex structure coal seam shows that the anchor-grouting strengthened support has achieved the expected ideal effect.
[0028] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.
Claims
1. A grouting reinforcement method for the soft bottom area of a steeply inclined complex structure coal seam, characterized in that: The following steps are involved: Step 1: Geological analysis: Analyze the soft bottom geology of the steeply inclined complex structure coal seam in the grouting reinforcement area; Step 2: Setting the grouting holes: Setting the positions and depths of the grouting holes according to the geological analysis materials in step 1; Step 3: Determine the grouting material: select the grouting material to be placed in the grouting hole according to the requirements of reinforcement hardness; Step 4: Prepare grouting material: prepare the selected grouting material and store it in a grouting tank; Step 5: Sealing the grouting hole: After cleaning the impurities in the grouting hole, insert the grouting pipe into the grouting hole and seal the gap between the grouting pipe and the grouting hole; Step 6: Material grouting: connect the grouting tank to the pump body, connect the pump body to the grouting pipe, and the pump body extracts the grouting material in the grouting tank and transports it to the grouting hole through the grouting pipe; Step 7: Clean the pipeline: The pressure sensor senses the pressure in the grouting hole in real time. When the set pressure value is reached, the grouting pipe is withdrawn and cleaned with cleaning equipment.
2. The grouting reinforcement method for the soft bottom area of a steeply inclined complex structure coal seam according to claim 1 is characterized by: The geological analysis in step 1 specifically includes the geological structure of the coal seam, the thickness of the coal seam, the inclination of the coal seam and the complexity of the geological structure.
3. The grouting reinforcement method for the soft bottom area of a steeply inclined complex structure coal seam according to claim 1 is characterized by: The positions of the grouting holes in the step 2 are specifically three grouting holes arranged in a single plane, and the three grouting holes are arranged at equal intervals, and the equal intervals are greater than or equal to 500 mm.
4. The method for grouting reinforcement of soft bottom area of steeply inclined complex structure coal seam according to claim 1, characterized in that: The depth of the grouting hole is specifically set by theoretical calculation method, tunnel observation method and borehole perspective method. The calculation formula of the theoretical calculation method is as follows: depth = rock layer depth - drainage depth - borehole length - grouting agent height difference. The tunnel observation method is determined according to the purpose of grouting, geological conditions and grouting material factors. The borehole perspective method drills two holes at a suitable location like the coal seam floor, places an infinite transmitter in one hole, and places a receiver in the other hole. Radio waves are attenuated to varying degrees when propagating in different media or in a damaged homogeneous body, and the magnitude of the attenuation is determined by the resistivity of the medium.
5. The method for grouting reinforcement of soft bottom area of steeply inclined complex structure coal seam according to claim 1, characterized in that: The grouting materials determined in step three are specifically classified into the first category, which is inorganic materials, mainly cement-based materials, such as cement, gypsum and various high-water materials, which do not produce chemical reactions when used; the second category is organic polymer materials, which are mainly polyurethane or other resin materials, which produce reaction heat of more than 120°C when used; and the third category is inorganic composite materials.
6. A grouting reinforcement method for the soft bottom area of a steeply inclined complex structure coal seam according to claim 5, characterized in that: The inorganic composite material is specifically HWI-reinforcement material and AKML-70 inorganic anchoring material. The HWI-reinforcement material is a composite grouting reinforcement material composed of inorganic ultrafine powder.
7. The method for grouting reinforcement of soft bottom area of steeply inclined complex structure coal seam according to claim 1, characterized in that: The sealing in step five is specifically to seal the grouting hole by wrapping hemp rope and covering it with epoxy resin material on the outside of the designated position of the grouting pipe.
8. The method for grouting reinforcement of soft bottom area of steeply inclined complex structure coal seam according to claim 1, characterized in that: The pressure value set in step seven is specifically 5.0 MPa as the final grouting pressure.