CN110926859A - Method for testing ground stress in deep part of coal mine - Google Patents
Method for testing ground stress in deep part of coal mine Download PDFInfo
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- CN110926859A CN110926859A CN201911241400.0A CN201911241400A CN110926859A CN 110926859 A CN110926859 A CN 110926859A CN 201911241400 A CN201911241400 A CN 201911241400A CN 110926859 A CN110926859 A CN 110926859A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/02—Devices for withdrawing samples
- G01N1/04—Devices for withdrawing samples in the solid state, e.g. by cutting
- G01N1/08—Devices for withdrawing samples in the solid state, e.g. by cutting involving an extracting tool, e.g. core bit
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L1/00—Measuring force or stress, in general
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
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Abstract
A method for testing the ground stress at deep position in coal mine includes such steps as determining the measuring points, determining the required test range and the geological state of mine, choosing the feasible positions on the plan of mine excavation, choosing the positions, avoiding the influence of underground excavation and fault zone, examining the positions chosen from the plan to underground, choosing the most suitable position, drilling holes at ①, choosing the tunnel in the region with better lithology, installing measuring points, and measuring the water and electricity in the tunnel.
Description
Technical Field
The invention relates to the technical field of ground stress testing, in particular to a method for testing ground stress in a deep part of a coal mine.
Background
The traditional theory is based on the hydrostatic pressure theory when the stability of mining engineering is evaluated by applying ground stress parameters. However, with the continuous expansion of mining scale and the continuous development to deep part, the influence of ground stress is more serious, such as prediction of ground surface subsidence deformation caused by coal mining, geological structure research, underground water permeability change caused by mining, mine water damage prevention and control and the like. Particularly, as the mining depth increases, the difference between the ground stress calculated based on the hydrostatic pressure theory and the actually measured ground stress is large, and the rock mechanics calculation performed according to the difference cannot meet the actual requirement, so that the improvement of the related technology is severely restricted. Therefore, in recent years, rock mechanics calculation based on ground stress actual measurement is widely applied to coal mine production, and under the condition, research on ground stress conditions of the whole mining area is increasingly necessary.
The system and theory of the ground stress testing method in the prior art need to be further improved, errors are easy to occur in the measuring process, the data deviation is large, and meanwhile, the ground stress measuring efficiency is reduced, so that the research and development of the ground stress testing method in the deep part of the coal mine are urgently needed.
Disclosure of Invention
This section is for the purpose of summarizing some aspects of embodiments of the invention and to briefly introduce some preferred embodiments. In this section, as well as in the abstract and the title of the invention of this application, simplifications or omissions may be made to avoid obscuring the purpose of the section, the abstract and the title, and such simplifications or omissions are not intended to limit the scope of the invention.
The invention has been developed in view of the above and/or other problems associated with existing methods for testing stresses in deep coal mines.
Therefore, the invention aims to provide a method for testing the ground stress at the deep part of the coal mine, realize systematic and theoretical measurement, improve the precision of data and improve the measurement efficiency.
To solve the above technical problem, according to an aspect of the present invention, the present invention provides the following technical solutions:
a coal mine deep crustal stress testing method comprises the following steps:
the method comprises the following steps: and (3) measuring point determination: according to the required test range and the mine field geological condition, according to the engineering purpose to be achieved by the determined ground stress measurement, firstly selecting some feasible position points on a mine excavation engineering plan, when selecting the positions, paying attention to avoid the influence of some larger structures such as underground excavation activities, fault zones and the like, simultaneously carrying out underground field investigation on the selected positions on the plan, and then selecting a most appropriate position;
step two: drilling a geological drill:
①, selecting a place, selecting a roadway in an area with better integral lithology, and installing a measuring point, wherein the water and electricity in the roadway are convenient to measure, the roadway transportation is not influenced when the geological drill works, the drilling machine is required to move quickly and conveniently, and enough drilling machine installation and coring space is provided;
② drilling and coring, using a drilling machine and a special coring sleeve and a drill bit, drilling a nearly horizontal drilling hole with a certain inclination angle, namely a large hole, with the diameter of 133mm on the rock wall of the roadway to be measured, taking out the rock core when the drilling hole reaches a preset length, and numbering and bagging to protect the rock core;
③ punching pericardium hole, and punching small bag hole with small drill bit of 370mm length and 40mm diameter;
④ flushing the drilled hole, drawing out the drill rod by 5cm after the small hole is formed, and flushing by using a water pipe of a drilling machine;
step three: installing a hollow bag body:
①, firstly, using a multimeter 2000 omega grade to measure whether each strain gauge of the hollow bag body is connected or not, wherein the connection reading of light green and other color strain gauge channels is 124 omega, and the reading of other two colors is 244 omega;
② measuring the length of big hole L1 and recording, and measuring the length of hollow inclusion as Lk 1;
③ drying and drilling, namely winding cotton yarn on the hole washer, pouring acetone, and conveying the hole washer to the bottom of the hole by using the mounting rod to perform drilling, drying and cleaning for one to two times;
④ preparing epoxy glue, weighing the epoxy glue and curing agent strictly by using an injector and a tray balance, placing in a beaker, and mixing uniformly;
⑤ installing a hollow bag body, polishing the surface of the hollow bag body, especially the position of a strain gauge, to a thickness of about 1mm by using abrasive paper, pouring the prepared epoxy glue into the cavity of the stress gauge, smearing butter in the positioning groove of the positioner, installing the hollow bag body on the positioner, carefully feeding the bag body into the small hole, extruding the epoxy glue from the inner cavity of the bag body to glue the hollow bag body with the wall of the drilled hole, and completely closing the hollow bag body;
step four: taking a guide wire rod: after 15h, the epoxy glue is tightly bonded, the position angle reading of the bag body, the azimuth angle and the inclination angle of the drilled hole are measured through the orientation instrument, then the drill rod and the orientation instrument are taken out and installed, and the cable of the positioner is pulled tightly when the rod is taken;
step five: stress relief:
① moving the drill back, aligning the hole precisely, then leading the lead cable of the hollow bag body out of the coring pipe, the drill rod hole, the drill and the modified water joint, connecting to the digital strain gauge, and only connecting 1-12 channels;
② connecting the drill rod and the pipeline and leading water;
③ starting the drilling machine to start water injection, wherein the reading of the strain gauge changes slightly, and the footage reading is started after the reading is stable;
④ starting the drilling machine, sleeving the core to remove stress, changing the strain value on the strain gauge, automatically recording the strain value in the strain gauge, taking out the core with the hollow inclusion after the core sleeving is finished, wrapping the core to prevent the change of lithology, bringing the core to the ground, and preparing for the next test.
The invention relates to a preferable scheme of a coal mine deep ground stress testing method, wherein: and the geological drilling hole drilling in the second step is inclined upwards by 3-20 degrees.
The invention relates to a preferable scheme of a coal mine deep ground stress testing method, wherein: the large hole is ground to be flat and then a horn hole is drilled, and when the small hole is drilled, the drill bit fully grinds and smoothes the small hole, the hole bottom is ground to be flat, and the diameter of the small hole is ensured to be suitable for installation of the hollow bag body.
The invention relates to a preferable scheme of a coal mine deep ground stress testing method, wherein: when drilling, a recording personnel needs to record the sequence of the core mark numbers taken out by the drilling personnel, and particularly, a section which is best close to the mounting small hole of the hollow bag body is determined.
The invention relates to a preferable scheme of a coal mine deep ground stress testing method, wherein: when the large hole is drilled, the drilled core is found to be excessively crushed, and another suitable drilled hole needs to be replaced in time in order to ensure the successful installation and removal of the hollow inclusion.
The invention relates to a preferable scheme of a coal mine deep ground stress testing method, wherein: when the hollow bag body is installed, the peeping probe and the digital display screen of the direction finder can clearly display the progress and the hole entering process of the bag body in the process of installing the hollow bag body.
Compared with the prior art: the system and the theoretical measurement are realized, the data precision is improved, and the measurement efficiency is improved.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and detailed embodiments, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without inventive exercise. Wherein:
FIG. 1 is a block diagram of the present invention.
Detailed Description
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be practiced in other ways than those specifically described herein, and it will be apparent to those of ordinary skill in the art that the present invention may be practiced without departing from the spirit and scope of the present invention, and therefore the present invention is not limited to the specific embodiments disclosed below.
In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in further detail below.
The invention provides a method for testing the ground stress of a coal mine deep part, which comprises the following steps:
the method comprises the following steps: and (3) measuring point determination: according to the required test range and the mine field geological condition, according to the engineering purpose to be achieved by the determined ground stress measurement, firstly selecting some feasible position points on a mine excavation engineering plan, when selecting the positions, paying attention to avoid the influence of some larger structures such as underground excavation activities, fault zones and the like, simultaneously carrying out underground field investigation on the selected positions on the plan, and then selecting a most appropriate position;
step two: drilling a geological drill:
①, selecting a place, selecting a roadway in an area with better integral lithology, and installing a measuring point, wherein the water and electricity in the roadway are convenient to measure, the roadway transportation is not influenced when the geological drill works, the drilling machine is required to move quickly and conveniently, and enough drilling machine installation and coring space is provided;
② punching and coring, wherein the geological drill needs to incline 3-20 degrees upwards to drain water and is easy to clean the drill hole, a drilling machine is used, a special coring sleeve and a drill bit are used, a nearly horizontal drill hole with a certain inclination angle and the diameter of 133mm, namely a large hole, is drilled on the rock wall of the measured roadway, and when the drill hole reaches a preset length, the rock core is taken out, and the number of the drill hole is numbered and the bag is used for protecting the rock core;
③, punching a hole in the pericardium, and punching a small bag body pinhole by a small drill bit with the length of 370mm and the diameter of 40mm, wherein the sequence of the marks of the cores taken out by a recording person is required on site during drilling, especially a section which is preferably closest to the hollow bag body installation pinhole is determined, and an irregular fracture surface of the cores is reserved to determine the corresponding direction of the cores of the bag body section which corresponds to the A strain rosette, so that the laboratory can measure the physical properties of the rocks conveniently;
④ flushing the drilled hole, drawing out the drill rod by 5cm after the small hole is formed, and flushing by using a water pipe of a drilling machine;
step three: installing a hollow bag body:
①, firstly, using a multimeter 2000 omega grade to measure whether each strain gauge of the hollow bag body is connected or not, wherein the connection reading of light green and other color strain gauge channels is 124 omega, and the reading of other two colors is 244 omega;
②, measuring and recording the length L1 of a big hole, measuring and measuring the length Lk1 of the hollow bag body, polishing the big hole, drilling a horn hole, polishing the small hole by a drill bit fully and smoothly when drilling the small hole, polishing the bottom of the hole flatly, ensuring that the diameter of the small hole is suitable for the installation of the hollow bag body, finding that the drilled core is excessively crushed when drilling the big hole, and needing to replace another suitable drilled hole in time for ensuring the successful installation and removal of the hollow bag body;
③ drying and drilling, namely winding cotton yarn on the hole washer, pouring acetone, and conveying the hole washer to the bottom of the hole by using the mounting rod to perform drilling, drying and cleaning for one to two times;
④ preparing epoxy glue, weighing the epoxy glue and curing agent strictly by using an injector and a tray balance, placing in a beaker, and mixing uniformly;
⑤ installing a hollow bag body, firstly polishing the surface of the hollow bag body, especially the position of a strain gauge, to a thickness of about 1mm by using abrasive paper, pouring the prepared epoxy glue into the cavity of the stress gauge, then smearing butter in the positioning groove of the positioner, installing the hollow bag body on the positioner, carefully feeding the bag body into the small hole, extruding the epoxy glue from the inner cavity of the bag body to glue the hollow bag body with the wall of the drilled hole, at the moment, the hollow bag body is completely closed, and when installing the hollow bag body, the peeping probe and the display screen of the orientation instrument can clearly display the progress and the hole entering process of the bag body in the process of installing the hollow bag body;
step four: taking a guide wire rod: after 15h, the epoxy glue is tightly bonded, the position angle reading of the bag body, the azimuth angle and the inclination angle of the drilled hole are measured through the orientation instrument, then the drill rod and the orientation instrument are taken out and installed, and the cable of the positioner is pulled tightly when the rod is taken;
step five: stress relief:
① moving the drill back, aligning the hole precisely, then leading the lead cable of the hollow bag body out of the coring pipe, the drill rod hole, the drill and the modified water joint, connecting to the digital strain gauge, and only connecting 1-12 channels;
② connecting the drill rod and the pipeline and leading water;
③ starting the drilling machine to start water injection, wherein the reading of the strain gauge changes slightly, and the footage reading is started after the reading is stable;
④ starting the drilling machine, sleeving the core to remove stress, changing the strain value on the strain gauge, automatically recording the strain value in the strain gauge, taking out the core with the hollow inclusion after the core sleeving is finished, wrapping the core to prevent the change of lithology, bringing the core to the ground, and preparing for the next test.
The method for testing the ground stress in the deep part of the coal mine can effectively improve the measurement of systematization and theorization, improve the precision of data and the efficiency of measurement, and has good economic benefit.
While the invention has been described above with reference to an embodiment, various modifications may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In particular, the various features of the disclosed embodiments of the invention may be used in any combination, provided that no structural conflict exists, and the combinations are not exhaustively described in this specification merely for the sake of brevity and resource conservation. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.
Claims (6)
1. A method for testing the ground stress at the deep part of a coal mine is characterized by comprising the following steps: the method for testing the ground stress at the deep part of the coal mine comprises the following steps:
the method comprises the following steps: and (3) measuring point determination: according to the required test range and the mine field geological condition, according to the engineering purpose to be achieved by the determined ground stress measurement, firstly selecting some feasible position points on a mine excavation engineering plan, when selecting the positions, paying attention to avoid the influence of some larger structures such as underground excavation activities, fault zones and the like, simultaneously carrying out underground field investigation on the selected positions on the plan, and then selecting a most appropriate position;
step two: drilling a geological drill:
①, selecting a place, selecting a roadway in an area with better integral lithology, and installing a measuring point, wherein the water and electricity in the roadway are convenient to measure, the roadway transportation is not influenced when the geological drill works, the drilling machine is required to move quickly and conveniently, and enough drilling machine installation and coring space is provided;
② drilling and coring, using a drilling machine and a special coring sleeve and a drill bit, drilling a nearly horizontal drilling hole with a certain inclination angle, namely a large hole, with the diameter of 133mm on the rock wall of the roadway to be measured, taking out the rock core when the drilling hole reaches a preset length, and numbering and bagging to protect the rock core;
③ punching pericardium hole, and punching small bag hole with small drill bit of 370mm length and 40mm diameter;
④ flushing the drilled hole, drawing out the drill rod by 5cm after the small hole is formed, and flushing by using a water pipe of a drilling machine;
step three: installing a hollow bag body:
①, firstly, using a multimeter 2000 omega grade to measure whether each strain gauge of the hollow bag body is connected or not, wherein the connection reading of light green and other color strain gauge channels is 124 omega, and the reading of other two colors is 244 omega;
② measuring the length of big hole L1 and recording, and measuring the length of hollow inclusion as Lk 1;
③ drying and drilling, namely winding cotton yarn on the hole washer, pouring acetone, and conveying the hole washer to the bottom of the hole by using the mounting rod to perform drilling, drying and cleaning for one to two times;
④ preparing epoxy glue, weighing the epoxy glue and curing agent strictly by using an injector and a tray balance, placing in a beaker, and mixing uniformly;
⑤ installing a hollow bag body, polishing the surface of the hollow bag body, especially the position of a strain gauge, to a thickness of about 1mm by using abrasive paper, pouring the prepared epoxy glue into the cavity of the stress gauge, smearing butter in the positioning groove of the positioner, installing the hollow bag body on the positioner, carefully feeding the bag body into the small hole, extruding the epoxy glue from the inner cavity of the bag body to glue the hollow bag body with the wall of the drilled hole, and completely closing the hollow bag body;
step four: taking a guide wire rod: after 15h, the epoxy glue is tightly bonded, the position angle reading of the bag body, the azimuth angle and the inclination angle of the drilled hole are measured through the orientation instrument, then the drill rod and the orientation instrument are taken out and installed, and the cable of the positioner is pulled tightly when the rod is taken;
step five: stress relief:
① moving the drill back, aligning the hole precisely, then leading the lead cable of the hollow bag body out of the coring pipe, the drill rod hole, the drill and the modified water joint, connecting to the digital strain gauge, and only connecting 1-12 channels;
② connecting the drill rod and the pipeline and leading water;
③ starting the drilling machine to start water injection, wherein the reading of the strain gauge changes slightly, and the footage reading is started after the reading is stable;
④ starting the drilling machine, sleeving the core to remove stress, changing the strain value on the strain gauge, automatically recording the strain value in the strain gauge, taking out the core with the hollow inclusion after the core sleeving is finished, wrapping the core to prevent the change of lithology, bringing the core to the ground, and preparing for the next test.
2. The method for testing the ground stress in the deep part of the coal mine according to claim 1, which is characterized in that: and the geological drilling hole drilling in the second step is inclined upwards by 3-20 degrees.
3. The method for testing the ground stress in the deep part of the coal mine according to claim 1, which is characterized in that: the large hole is ground to be flat and then a horn hole is drilled, and when the small hole is drilled, the drill bit fully grinds and smoothes the small hole, the hole bottom is ground to be flat, and the diameter of the small hole is ensured to be suitable for installation of the hollow bag body.
4. The method for testing the ground stress in the deep part of the coal mine according to claim 1, which is characterized in that: when drilling, a recording personnel needs to record the sequence of the core mark numbers taken out by the drilling personnel, and particularly, a section which is best close to the mounting small hole of the hollow bag body is determined.
5. The method for testing the ground stress in the deep part of the coal mine according to claim 1, which is characterized in that: when the large hole is drilled, the drilled core is found to be excessively crushed, and another suitable drilled hole needs to be replaced in time in order to ensure the successful installation and removal of the hollow inclusion.
6. The method for testing the ground stress in the deep part of the coal mine according to claim 1, which is characterized in that: when the hollow bag body is installed, the peeping probe and the digital display screen of the direction finder can clearly display the progress and the hole entering process of the bag body in the process of installing the hollow bag body.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN201911241400.0A CN110926859A (en) | 2019-12-06 | 2019-12-06 | Method for testing ground stress in deep part of coal mine |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201911241400.0A CN110926859A (en) | 2019-12-06 | 2019-12-06 | Method for testing ground stress in deep part of coal mine |
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| CN110926859A true CN110926859A (en) | 2020-03-27 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111855271A (en) * | 2020-07-28 | 2020-10-30 | 中国海洋石油集团有限公司 | Coring instrument capable of drilling rock core in specified direction in well |
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2019
- 2019-12-06 CN CN201911241400.0A patent/CN110926859A/en not_active Withdrawn
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111855271A (en) * | 2020-07-28 | 2020-10-30 | 中国海洋石油集团有限公司 | Coring instrument capable of drilling rock core in specified direction in well |
| CN111855271B (en) * | 2020-07-28 | 2023-09-15 | 中国海洋石油集团有限公司 | Coring instrument capable of drilling underground designated azimuth core |
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Application publication date: 20200327 |