CN109341449B - Sectional control blasting well completion method for one-time rock drilling of large-section high raise - Google Patents
Sectional control blasting well completion method for one-time rock drilling of large-section high raise Download PDFInfo
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- CN109341449B CN109341449B CN201811227028.3A CN201811227028A CN109341449B CN 109341449 B CN109341449 B CN 109341449B CN 201811227028 A CN201811227028 A CN 201811227028A CN 109341449 B CN109341449 B CN 109341449B
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F42—AMMUNITION; BLASTING
- F42D—BLASTING
- F42D1/00—Blasting methods or apparatus, e.g. loading or tamping
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F42—AMMUNITION; BLASTING
- F42D—BLASTING
- F42D1/00—Blasting methods or apparatus, e.g. loading or tamping
- F42D1/08—Tamping methods; Methods for loading boreholes with explosives; Apparatus therefor
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F42—AMMUNITION; BLASTING
- F42D—BLASTING
- F42D3/00—Particular applications of blasting techniques
- F42D3/04—Particular applications of blasting techniques for rock blasting
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Abstract
The invention discloses a sectional control blasting well completion method for one-time rock drilling of a large-section raise shaft, which comprises the following steps of (1) determining the type of a drilling machine; (2) determining the specification of a primary blasting well; (3) a compensation space; (4) determining a blast hole; (5) charging; (6) a differential time; (7) detonating; the invention has the advantages that the whole construction process of drilling, charging and blasting is carried out by a 70-meter large-section high-one-time well-completion technology, and constructors complete the whole construction process in the upper rock drilling chamber, so that unmanned operation in the inner part and the lower part of the raise is realized, and potential safety hazards such as falling at high altitude, falling objects at high altitude, falling rocks on a top plate and the like are avoided; a special fan or an air pipe is not required for ventilation; a crawling ladder and an operation platform are not required to be built, an air-leg rock drill is not required to be used, the cost is saved, the labor intensity is low, the operation condition is good, and the intrinsically safe operation is realized; the one-time rock drilling and sectional blasting method has simple working procedures, and the construction period is 22 to 27 days from drilling to blasting to well formation.
Description
Technical Field
The invention relates to a coal mining method, in particular to a one-time rock drilling and subsection control blasting well completion method for a large-section high raise.
Technical Field
In the underground mining of iron ore, a full-stage (upward and downward) combined blasting mining method, namely an FCM method, is mainly adopted, and in the construction of extending of mine cutting patios, ore pass shafts and blind vertical shafts of the same type, the patio tunneling is always a difficult problem in the mine mining industry and is also the most important link of the mine mining due to the large height and the large hardness of the ore.
In conventional mining methods, such as the conventional method, the hanging can method, etc.; the ordinary method is used for tunneling the raise generally with the height of less than 60 meters, an air-leg rock drill is used for drilling an upward hole, a pedestrian ladder is installed, a support is erected, and a workbench moves upwards along with tunneling. Before blasting, equipment such as the platform, the air and water pipe and the drilling machine are removed, and blasting damage is prevented. The raise is tunneled in an upward reverse tunneling mode, ventilation is difficult, and ventilation time is long. The process has the defects of complex working procedures, high working platform frame, high labor intensity, low tunneling speed, low efficiency, long ventilation time, high material consumption, high cost, unsafe operation and the like.
Although the construction procedures are reduced and the ventilation and the working environment are improved in the construction of the cutting well by the tank lifting method, personnel need to construct in the cutting well, and meanwhile, auxiliary personnel are added, so that the capital investment is large.
The raise boring machine method is a method of forming holes by using rotary drilling to break rock and reversely expand holes, and using hobbing cutter to extrude, scrape and shear the broken rock into well.
The common method and the raise boring machine method can perform groove broaching only by performing secondary expanding brushing on the cutting well, and have the problems of complex procedure, poor construction effect, insufficient groove expanding height and the like.
Disclosure of Invention
The invention aims to provide a one-time rock drilling and subsection control blasting well completion method for a large-section high raise, which can improve the construction efficiency of a cutting well, improve the construction safety coefficient, reduce the labor intensity of workers, improve the construction environment, and is short in construction period and safe in mine exploitation.
In order to solve the technical problems, the invention provides a sectional control blasting well-forming method for one-time rock drilling of a large-section raise shaft, which has the technical key points as follows:
(1) determining the type of a drilling machine according to the properties of mine rock masses, the blasting charge amount and the like, and determining the diameter of a drilled hole according to the type of the drilling machine;
(2) determining the specification of a primary blasting well, wherein the height of a raise section is mainly related to rock properties and a compensation space, the height of a raise section of 70 meters is large, a section of 3 meters by 3 meters is adopted, and the height of the blasting section is 5 meters;
(3) the compensation space is used for accommodating each subsection blasting broken rock, after each subsection blasting, the rock blocks fall into the lower chamber to form a pile, the height of a primary blasting raise section is set to be H, the section area is set to be S, the raise inclination angle is set to be alpha, and the height of the lower chamber is set to be H;
Vb＝Sh
Vz＝SH(k-1)/sinα
in the formula, Vb is a rock mass compensation space; vz is the volume of the rock mass after crushing and expansion, and k is the crushing and expansion coefficient; if the rocks which want to be caved down can be completely accommodated by the lower rock engineering chamber, Vb is required to be larger than Vz;
(4) according to the action of each blast hole in the patio, cut holes are arranged on the periphery of a central blast hole, peripheral holes are arranged at the positions forming the patio shape, and the peripheral holes are arranged at four corners of the patio outline;
(5) charging, namely, adopting blasting chemicals matched with the blasting resistance line;
(6) the differential time is T between the first shot hole and the second shot hole
T＝t1+t2+t3
t1 is the time for the occurrence of cracks and the expansion of the cracks of the rock, t2 is the time for throwing the rock slag to fill the cavity, and t3 is the time for the rock slag to fall off to form the cavity;
(7) in order to ensure that enough free surface exists during blasting of the back blasting hole and improve blasting quality, a half-second delay detonating tube detonator is connected with a detonating cord for detonation, and a detonating cartridge is placed at the bottom of the blasting hole.
Preferably, the section area of the raise is determined according to the maximum size of the lump ore of the ore falling, and the section of the wellhead is gradually reduced as the well depth is increased and the well head is upward; the area of the cross section is 9 square meters, the compensation coefficient is 0.55-0.7, and the height of a single blasting section can reach 5-7 meters; if the compensation coefficient is less than 0.5, the height of a single blasting section is 2-4 meters; the well is blasted in soft rock, the blasting section height can be more than 10 meters, and for rock stratum properties of medium hardness and above, the blasting section height should be less than 10 meters.
Preferably, the blast holes are detonated one by one, and if the time difference is very large, the raise can be realized as long as the distance between the blast holes reaches the standard and the rock breaking volume can be accommodated by the lower chamber no matter how the blast holes are arranged; however, in order to facilitate the construction of the drilling machine, the positions of blast holes still need to be arranged according to a certain rule.
Preferably, the reasonable differential time between the auxiliary holes and the cut holes is generally 95-105ms, and the reasonable differential time between the peripheral holes and the auxiliary holes is more than 150ms, so that a better blasting effect can be obtained.
Preferably, the explosive with the detonation velocity of about 3000m/s is suitable for medium-hard rock and can achieve a better blasting effect; the explosive with the detonation velocity of about 4000m/s is suitable for hard rock, and the detonation effect is good; in addition, in order to prevent the first shot hole from being impacted, because the detonation energy is too large, too large impact dynamic pressure is caused, broken rocks are blocked in the hole, the determination of the charging structure, the charging density and the charging amount of the first shot hole is very important, the great influence is brought to the initiation of the subsequent shot hole, and the blasting effect is determined.
Preferably, in order to prevent the blasting failure and influence the blasting quality of the blast holes, each blast hole is detonated by a double-conductive-tube detonator.
The invention has the advantages that the whole construction process of drilling, charging and blasting is carried out by a 70-meter large-section high-one-time well-completion technology, and constructors complete the whole construction process in the upper rock drilling chamber, so that unmanned operation in the inner part and the lower part of the raise is realized, and potential safety hazards such as falling at high altitude, falling objects at high altitude, falling rocks on a top plate and the like are avoided; a special fan or an air pipe is not required for ventilation; a crawling ladder and an operation platform are not required to be built, an air-leg rock drill is not required to be used, the cost is saved, the labor intensity is low, the operation condition is good, and the intrinsically safe operation is realized; the one-time rock drilling and sectional blasting method has simple working procedures, and the construction period is 22 to 27 days from drilling to blasting to well formation.
Drawings
FIG. 1 is a schematic view of the present invention of hole distribution
Detailed Description
The present invention will be described in further detail in order to make the objects, technical solutions and advantages of the present invention more apparent.
The invention provides a sectional control blasting well completion method for one-time rock drilling of a large-section raise shaft, which has the technical key points as follows:
(1) determining the type of a drilling machine according to the properties of mine rock masses, the blasting charge amount and the like, and determining the diameter of a drilled hole according to the type of the drilling machine;
(2) determining the specification of a primary blasting well, wherein the height of a raise section is mainly related to rock properties and a compensation space, the height of a raise section of 70 meters is large, a section of 3 meters by 3 meters is adopted, and the height of the blasting section is 5 meters;
(3) the compensation space is used for accommodating each subsection blasting broken rock, after each subsection blasting, the rock blocks fall into the lower chamber to form a pile, the height of a primary blasting raise section is set to be H, the section area is set to be S, the raise inclination angle is set to be alpha, and the height of the lower chamber is set to be H;
Vb＝Sh
Vz＝SH(k-1)/sinα
in the formula, Vb is a rock mass compensation space; vz is the volume of the rock mass after crushing and expansion, and k is the crushing and expansion coefficient; if the rocks which want to be caved down can be completely accommodated by the lower rock engineering chamber, Vb is required to be larger than Vz;
(4) according to the action of each blast hole in the patio, cut holes are arranged on the periphery of a central blast hole, peripheral holes are arranged at the positions forming the patio shape, and the peripheral holes are arranged at four corners of the patio outline;
(5) charging, namely, adopting blasting chemicals matched with the blasting resistance line;
(6) the differential time is T between the first shot hole and the second shot hole
T＝t1+t2+t3
t1 is the time for the occurrence of cracks and the expansion of the cracks of the rock, t2 is the time for throwing the rock slag to fill the cavity, and t3 is the time for the rock slag to fall off to form the cavity;
(7) in order to ensure that enough free surface exists during blasting of the back blasting hole and improve blasting quality, a half-second delay detonating tube detonator is connected with a detonating cord for detonation, and a detonating cartridge is placed at the bottom of the blasting hole.
Preferably, the section area of the raise is determined according to the maximum size of the lump ore of the ore falling, and the section of the wellhead is gradually reduced as the well depth is increased and the well head is upward; the area of the cross section is 9 square meters, the compensation coefficient is 0.55-0.7, and the height of a single blasting section can reach 5-7 meters; if the compensation coefficient is less than 0.5, the height of a single blasting section is 2-4 meters; the well is blasted in soft rock, the blasting section height can be more than 10 meters, and for rock stratum properties of medium hardness and above, the blasting section height should be less than 10 meters.
Preferably, the blast holes are detonated one by one, and if the time difference is very large, the raise can be realized as long as the distance between the blast holes reaches the standard and the rock breaking volume can be accommodated by the lower chamber no matter how the blast holes are arranged; however, in order to facilitate the construction of the drilling machine, the positions of blast holes still need to be arranged according to a certain rule.
Preferably, the reasonable differential time between the auxiliary holes and the cut holes is generally 95-105ms, and the reasonable differential time between the peripheral holes and the auxiliary holes is more than 150ms, so that a better blasting effect can be obtained.
Preferably, the explosive with the detonation velocity of about 3000m/s is suitable for medium-hard rock and can achieve a better blasting effect; the explosive with the detonation velocity of about 4000m/s is suitable for hard rock, and the detonation effect is good; in addition, in order to prevent the first shot hole from being impacted, because the detonation energy is too large, too large impact dynamic pressure is caused, broken rocks are blocked in the hole, the determination of the charging structure, the charging density and the charging amount of the first shot hole is very important, the great influence is brought to the initiation of the subsequent shot hole, and the blasting effect is determined.
Preferably, in order to prevent the blasting failure and influence the blasting quality of the blast holes, each blast hole is detonated by a double-conductive-tube detonator.
The invention has the advantages that the whole construction process of drilling, charging and blasting is carried out by a 70-meter large-section high-one-time well-completion technology, and constructors complete the whole construction process in the upper rock drilling chamber, so that unmanned operation in the inner part and the lower part of the raise is realized, and potential safety hazards such as falling at high altitude, falling objects at high altitude, falling rocks on a top plate and the like are avoided; a special fan or an air pipe is not required for ventilation; a crawling ladder and an operation platform are not required to be built, an air-leg rock drill is not required to be used, the cost is saved, the labor intensity is low, the operation condition is good, and the intrinsically safe operation is realized; the one-time rock drilling and sectional blasting method has simple working procedures, and the construction period is 22 to 27 days from drilling to blasting to well formation.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are included in the scope of the present invention.
Claims (5)
1. The sectional control blasting well completion method for one-time rock drilling of the large-section high raise is characterized by comprising the following steps of:
(1) determining the type of a drilling machine according to the properties of mine rock masses, the blasting charge amount and the like, and determining the diameter of a drilled hole according to the type of the drilling machine;
(2) determining the specification of a primary blasting well, wherein the height of a raise section is mainly related to rock properties and a compensation space, the height of a raise section of 70 meters is large, a section of 3 meters by 3 meters is adopted, and the height of the blasting section is 5 meters;
(3) the compensation space is used for accommodating each subsection blasting broken rock, after each subsection blasting, the rock blocks fall into the lower chamber to form a pile, the height of a primary blasting raise section is set to be H, the section area is set to be S, the raise inclination angle is set to be alpha, and the height of the lower chamber is set to be H;
Vb＝Sh
Vz＝SH(k-1)/sinα
in the formula, Vb is a rock mass compensation space; vz is the volume of the rock mass after crushing and expansion, and k is the crushing and expansion coefficient; if the rocks which want to be caved down can be completely accommodated by the lower rock engineering chamber, Vb is required to be larger than Vz;
(4) according to the action of each blast hole in the patio, cut holes are arranged on the periphery of a central blast hole, peripheral holes are arranged at the positions forming the patio shape, and the peripheral holes are arranged at four corners of the patio outline;
(5) charging, namely, adopting blasting chemicals matched with the blasting resistance line;
(6) the differential time is T between the first shot hole and the second shot hole
T＝t1+t2+t3
t1 is the time for the occurrence of cracks and the expansion of the cracks of the rock, t2 is the time for throwing the rock slag to fill the cavity, and t3 is the time for the rock slag to fall off to form the cavity;
(7) and (3) connecting a detonating fuse with a half-second delay detonating tube detonator for detonating, and placing a detonating explosive package at the bottom of the blast hole.
2. The method for forming the shaft of the large-section raise shaft through one-time rock drilling and sectional control blasting according to claim 1, wherein the raise shaft can be realized no matter how the blast holes are arranged and the rock breaking volume can be accommodated by a lower chamber as long as the distance between the blast holes reaches the standard, if the blast holes are detonated one by one and the time difference is large; however, in order to facilitate the construction of the drilling machine, the positions of blast holes still need to be arranged according to a certain rule.
3. A sectional control blasting well completion method for one-time rock drilling of a large-section raise shaft according to claim 1, characterized in that the reasonable differential time between the auxiliary holes and the cut holes is generally 95-105ms, and the reasonable differential time between the peripheral holes and the auxiliary holes is more than 150ms, so that a better blasting effect can be obtained.
4. The method for forming the well by the one-time rock drilling and the sectional control blasting of the large-section raise shaft according to claim 1, wherein the explosive with the blasting speed of about 3000m/s is suitable for medium-hard rock and can achieve a good blasting effect; the explosive with the detonation velocity of about 4000m/s is suitable for hard rock and has good detonation effect.
5. The method for achieving the large-section high-rise well through one-time rock drilling and section control blasting according to claim 1, wherein each blast hole is detonated through a double-lead blasting cap.
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| CN110043302B (en) * | 2019-05-28 | 2021-07-20 | 河南发恩德矿业有限公司 | Safe and efficient construction method for long-distance single-head tunneling surface ventilation patio |
| CN110307762B (en) * | 2019-08-08 | 2023-11-21 | 福州大学 | Quick well forming method for courtyard based on deep hole-by-hole detonation technology |
| CN110578465A (en) * | 2019-08-27 | 2019-12-17 | 湖南柿竹园有色金属有限责任公司 | One-time well drilling and hole distribution method |
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| CN112179225A (en) * | 2020-09-27 | 2021-01-05 | 鞍钢集团矿业有限公司 | One-time well-completion blasting method |
| CN112211639A (en) * | 2020-10-13 | 2021-01-12 | 宝钢集团新疆八一钢铁有限公司 | One-step well completion method for high-depth large-section medium-deep hole |
| CN114001606B (en) * | 2021-10-27 | 2023-03-28 | 湖南柿竹园有色金属有限责任公司 | Method for enlarging and distributing holes of circular shaft |
| CN113983883B (en) * | 2021-10-27 | 2023-04-11 | 湖南柿竹园有色金属有限责任公司 | Sectional energy-gathering detonation one-time well completion method in deep hole |
| CN114688928A (en) * | 2022-02-18 | 2022-07-01 | 安徽开发矿业有限公司 | Large-aperture drilling one-time blasting well-forming blast hole arrangement and blasting method for ultra-deep cutting (slip) well |
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Denomination of invention: A method of one-time rock drilling and subsection controlled blasting for large section high raise Effective date of registration: 20220107 Granted publication date: 20210219 Pledgee: China Construction Bank Corporation Linyi Luozhuang sub branch Pledgor: LINYI HUI BAO LING IRON Co.,Ltd. Registration number: Y2022980000200 |
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