CN216741503U - Bottom structure of medium-length hole stope easy to recycle - Google Patents
Bottom structure of medium-length hole stope easy to recycle Download PDFInfo
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- CN216741503U CN216741503U CN202220125638.8U CN202220125638U CN216741503U CN 216741503 U CN216741503 U CN 216741503U CN 202220125638 U CN202220125638 U CN 202220125638U CN 216741503 U CN216741503 U CN 216741503U
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Abstract
The utility model provides an easily-recycled bottom structure of a medium-length hole stope, which comprises a plurality of adjacent unit stopes, wherein each unit stope comprises two adjacent sectional stopes which are distributed in a mirror symmetry manner, drilling tunnels which are respectively arranged at the bottoms of the two sectional stopes and a large triangular ore pillar between the two drilling tunnels, and the two drilling tunnels are respectively clung to two boundaries of the unit stopes and are distributed in a mirror symmetry manner; the large triangular ore pillar comprises a small-section rock drilling roadway arranged at the bottom of the middle of the large triangular ore pillar, a plurality of upward medium-length hole blast holes extending from the small-section rock drilling roadway to the free surface of the large triangular ore pillar and horizontal medium-length hole blast holes, so that the large triangular ore pillar is recycled. According to the utility model, by optimizing the bottom structure of the medium-length hole stope, the quantity of the bottom pillars to be recovered is reduced, the volume is increased, the mining and cutting engineering quantity is reduced, and the recovery process is convenient; still improved the rate of recovery of sill pillar, the mining efficiency and the ore recovery rate in whole panel stope, and the stability and the security of big sill pillar are higher.
Description
Technical Field
The utility model relates to the technical field of stope recovery structures, in particular to a bottom structure of a medium-length hole stope, which is easy to recover.
Background
The ore recovery rate, also called mining recovery rate, is the percentage of the extracted quantity of underground mineral resources; the method is a very important technical index for evaluating the mining working quality and the utilization degree of underground mineral resources, and is also closely related to the economic benefit of mineral resource development. At present, when most medium-length hole stopes are mined, the sector medium-length holes are generally constructed from a rock drilling roadway at the bottom, explosive charging and blasting are carried out to realize ore caving, then a trench bottom structure is adopted to carry out ore removal, and a V-shaped structure is formed at the bottom of the stope by the mining and ore removal mode. In the blasting production process of normal row face in stope, the ore of trench bottom structure can't be retrieved along with normal blasting process, leads to the whole rate of recovery of stope ore to be on the low side. Mining ore recovery rates are low, which results in waste of mineral resources and reduced mine output, thus resulting in low economic benefits in the mine.
In the prior art, in the construction process of medium-length hole stopes, two adjacent stopes all adopt trench bottom structures to carry out ore removal, so that triangular ore pillars are formed at the adjacent positions of the two stopes, and the recovery of the triangular ore pillars is a difficult problem which puzzles mine production. When the quality of a filling body of a stope is poor, the triangular ore pillar reserves the dado ore with large thickness, and the part of ore can not be recovered, so that the recovery rate of the ore pillar is low, and the recovery rate of the whole stope is low. In addition, the triangular ore pillars of the stope are small in size and are influenced by selection of ore pillar recovery construction equipment, and recovery work is difficult. Therefore, it is urgently needed to research a bottom recovery structure of a medium-length hole stope, which is easy to recover, does not increase the mining and cutting workload of the stope, has high safety, and can improve the ore recovery rate of the stope.
In view of the above, there is a need for an improved bottom structure of a medium-length stope, which is easy to recover, to solve the above problems.
SUMMERY OF THE UTILITY MODEL
The utility model aims to provide an easily-recycled bottom structure of a medium-length hole stope, which is characterized in that a triangular large ore pillar which is easy to recycle in the middle of a unit stope is obtained by dividing unit stopes of the medium-length hole stope and optimizing the bottom structure of the unit stope; through the small-section rock drilling roadway arranged in the middle of the bottom of the large triangular ore pillar and the plurality of medium-length hole blast holes extending from the small-section rock drilling roadway to the free surface of the large triangular ore pillar, the recovery of the large triangular ore pillar at the bottom of a stope is realized. The triangular large ore pillar at the bottom of the stope has larger size, is easy to recover, reduces the mining and cutting engineering quantity, improves the mining efficiency and the ore recovery rate, and has higher application value.
In order to realize the purpose of the utility model, the utility model provides an easily-recycled bottom structure of a medium-length hole stope, which comprises a plurality of adjacent unit stopes, wherein each unit stope comprises two adjacent sublevel stopes which are distributed in a mirror symmetry manner, rock drilling roadways which are respectively arranged at the bottoms of the two sublevel stopes and a triangular large ore pillar which is arranged between the two rock drilling roadways; the two rock drilling tunnels are respectively close to two boundaries of the unit stope and are distributed in a mirror symmetry mode;
the big ore pillar of triangle includes the middle bottom set up little section rock drilling tunnel, by little section rock drilling tunnel to a plurality of upward medium-length hole big gun holes and the horizontal medium-length hole big gun hole that the free surface of the big ore pillar of triangle extends, it is right to realize the recovery of the big ore pillar of triangle.
As a further improvement of the utility model, the small-section rock drilling roadway and the rock drilling roadway are arranged along the trend of the ore body of the stope and are arranged in parallel.
As a further improvement of the method, in the extending direction of the small-section rock drilling roadway, the upward medium-length hole blast holes and the horizontal medium-length hole blast holes are kept in the same row, and the row spacing is 2.2-2.8 m.
As a further improvement of the utility model, the blast holes of the upward medium-length hole are distributed on the same row of surfaces in a fan-shaped structure, and the distance between the blast holes of the upward medium-length hole and the bottom of the horizontal medium-length hole is 2-3 m.
As a further improvement of the utility model, the hole bottom distance between a plurality of the upward medium-length hole blast holes on the same row of surfaces is 2.0-2.5 m.
As a further improvement of the utility model, the sublevel stope is also provided with a high-strength filling body in the external space of the free surface of the large triangular pillar and the rock drilling roadway.
As a further improvement of the utility model, a vein-passing ore removal roadway, a middle-section transportation flat roadway, a ore-sliding connection roadway and a ore-sliding shaft are also arranged in the unit stope.
As a further improvement of the utility model, the drift ore removal roadway is communicated with the rock drilling roadway of the adjacent sublevel stope, so that convenient ore removal is realized during normal mining.
As a further improvement of the utility model, the middle-section transportation flat roadways are arranged into two groups and are respectively arranged at the front end and the rear end of the bottom of the medium-length hole stope, and the middle-section transportation flat roadways are arranged perpendicular to the rock drilling roadway.
As a further improvement of the utility model, the included angle between the vein-passing ore removal roadway and the rock drilling roadway is 40-50 degrees, and the distance between two adjacent vein-passing ore removal roadways is 10-12 m.
The utility model has the beneficial effects that:
1. the bottom structure of the medium-length hole stope easy to recover comprises a plurality of adjacent unit stopes, wherein each unit stope comprises two adjacent sectional stopes which are in mirror symmetry distribution, drilling tunnels which are respectively arranged at the bottoms of the two sectional stopes and a triangular large ore pillar between the two drilling tunnels, and the two drilling tunnels are respectively attached to two boundaries of the unit stopes and are in mirror symmetry distribution; the large triangular ore pillar comprises a small-section rock drilling roadway arranged at the bottom of the middle part, a plurality of medium-length hole blast holes extending from the small-section rock drilling roadway to the free surface of the large triangular ore pillar and horizontal medium-length hole blast holes, so that the large triangular ore pillar can be recycled. According to the utility model, the bottom structure of the medium-deep hole stope is changed, so that the number of the bottom pillars required to be recovered in the subsequent engineering is reduced, only one bottom pillar is required to be recovered in every two sectional stopes, the mining and cutting engineering quantity is reduced, and the recovery rate of the bottom pillars is improved; and the stability and the security of big base pillar are higher.
2. The utility model takes two adjacent sectional stopes which are distributed in mirror symmetry as a unit stope, and small-section rock drilling tunnels are tunneled in the middle of large triangular pillars formed in the unit stope; recovering the triangular large ore pillars after upward medium-length hole blast holes and horizontal medium-length hole blast holes are constructed in the rock drilling roadway; and (5) recovering the large triangular ore pillars in the bottom structure in the whole medium-length hole stope by adopting the same method. The method takes two sectional stopes as unit stopes, forms large-volume ore pillars by changing the position of a rock drilling roadway, and recovers the ore pillars, thereby reducing the loss rate of ores; and the triangular large ore pillar at the bottom of the stope is large in size and easy to recover, the mining and cutting work amount is reduced, the mining efficiency and the ore recovery rate are improved, and the application value is high.
Drawings
Fig. 1 is a schematic view of a unit stope with an easily recyclable medium-length hole stope bottom structure according to the present invention.
Fig. 2 is a stope distribution diagram of the bottom structure of the medium-length hole stope easy to recover.
Fig. 3 is a top sectional view of a stope in an embodiment of the utility model.
Reference numerals
100-unit stope; 1-sectional stope; 11-rock drilling roadway; 12-triangular large pillar; 121-small section rock drilling roadway; 122-upward medium-length hole blast holes; 123-horizontal medium-length hole blast holes; 2-drawing a vein through ore removal roadway; 3-middle section transportation flat roadway; 4-ore pass communication roadway; 5-slipping in a mine.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in detail with reference to the accompanying drawings and specific embodiments.
It should be noted that, in order to avoid obscuring the present invention with unnecessary details, only the structures and/or processing steps closely related to the aspects of the present invention are shown in the drawings, and other details not closely related to the present invention are omitted.
In addition, it should be further noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
Examples
Referring to fig. 1-2, an easily-recycled bottom structure of a medium-length hole stope comprises a plurality of adjacent unit stopes 100, wherein each unit stope 100 comprises two adjacent sublevel stopes 1 which are distributed in a mirror symmetry manner, a rock drilling roadway 11 which is respectively arranged at the bottom of each sublevel stope 1, and a triangular large ore pillar 12 between the two rock drilling roadways 11; two rock drilling tunnels 11 are respectively and closely attached to two boundaries of the unit stope 100 and are distributed in a mirror symmetry mode; the large triangular pillar 12 comprises a small-section rock drilling roadway 121 arranged at the bottom of the middle, a plurality of upward medium-length hole blast holes 122 extending from the small-section rock drilling roadway 121 to the free surface of the large triangular pillar 12, and a horizontal medium-length hole blast hole 123, so that the large triangular pillar 12 is recovered. The small-section rock drilling roadway 121 and the rock drilling roadway 11 are arranged along the trend of the ore body of the stope and are arranged in parallel. According to the utility model, the bottom structure of the medium-deep hole stope is changed, so that the number of the bottom pillars required to be recovered in the subsequent engineering is reduced, only one bottom pillar needs to be recovered in every two sectional stopes 1, the mining and cutting engineering quantity is reduced, and the recovery rate of the bottom pillars is improved; and the stability and the safety of the triangular large pillar 12 are higher.
The position of the rock drilling roadway 11 is modified from the traditional arrangement at the center of the stope to the arrangement at two boundaries close to the unit stope 100; such two adjacent sublevel stopes 11 form a triangular large pillar 12 which is larger in volume and easy to recover. According to the utility model, the bottom structure of the medium-deep hole stope is changed, so that the number of the bottom pillars required to be recovered is reduced, only one bottom pillar is required to be recovered in every two stopes, the mining and cutting engineering quantity is reduced, the recovery rate can reach 40-60%, and compared with the recovery rate of a traditional bottom pillar recovery mode which is 20-40%, the recovery rate of the bottom pillars is greatly improved, and the economic benefit of mining is improved; and the stability and the security of big base pillar are higher, are favorable to safe construction.
It should be noted that, by adopting the mining process of the stope bottom structure of the utility model, the unit stopes 100 in the whole panel area need to be mined at intervals, the unit stopes 100 at intervals can be mined simultaneously, two sublevel stopes 1 in the same unit stope 100 can be mined simultaneously, and the filling is carried out after the whole unit stope 100 is mined; by adopting the mode of mining and filling, the stability of the adjacent unit stopes 100 during mining can be further ensured.
In some specific embodiments, two drilling roadways 11 in each unit stope 100 may be spaced from the boundary of the stope by a distance between the central axes of the two drilling roadways 11 that is greater than the width of a single sublevel stope 1; the distance between the central axes of the two rock drilling roadways 11 is 1.2-1.47 times of the width of a single sublevel stope 1. With the arrangement, two small ore pillars are respectively formed at the two boundaries of the rock drilling roadway 11 and the unit stope 100, and the small ore pillars do not need to be recovered, but only the large triangular ore pillars 12 need to be recovered; at this time, the unit panels 100 in the whole panel may not follow the principle of the cut-and-fill but still adopt the cut-and-fill mode.
In the extending direction of the small-section rock drilling roadway 121, the upward medium-length hole blast holes 122 and the horizontal medium-length hole blast holes 123 are in the same row, and the row spacing is 2.2-2.8 m; the upward medium-length hole blast holes 122 are distributed in an upward fan-shaped structure on the same row surface, and the distance between the upward medium-length hole blast holes 122 and the bottom of the horizontal medium-length hole blast holes 123 is 2-3 m; the distance between the bottoms of a plurality of upward medium-length hole blast holes 122 on the same row of surfaces is 2.0-2.5 m. So set up, guarantee the comprehensive nature of blasting, improve the ore recovery rate of big ore pillar 12 of triangle, finally improve the recovery rate and the economic benefits of whole stope.
Particularly, the sublevel stope 1 is also provided with high-strength filling bodies in the external space of the free surface of the large triangular pillar 12 and the rock drilling roadway 11, and the stability of the stope and the construction safety can be ensured by the high-strength filling bodies.
Referring to fig. 3, in the specific application of the present invention, a vein-through ore removal roadway 2, a middle-section transportation flat roadway 3, a ore-pass communication roadway 4 and an ore-pass shaft 5 are further disposed in the unit stope 100. The vein-penetrating ore removal roadway 2 is communicated with the rock drilling roadway of the adjacent sublevel stope 1, so that convenient ore removal is realized. The middle section transportation flat laneways 3 are arranged into two groups and are respectively arranged at the front end and the rear end of the bottom of the medium-length hole stope, and the middle section transportation flat laneways 3 are perpendicular to the rock drilling laneways 11. The included angle between the vein-penetrating ore removal roadway 2 and the rock drilling roadway 11 is 40-50 degrees, and the distance between two adjacent vein-penetrating ore removal roadways 2 is 10-12 m. So set up, when the stope normally mined, the ore both can carry out the ore removal from the stope front and back, also can follow 2 intercommunication adjacent segmentation stopes of drawing a mine drift of drawing a vein 1 and carry out the ore removal, has increased the ore removal route of stope, realizes convenient ore removal, has improved mining efficiency.
In some embodiments, after loading explosive in the blast holes of the upward medium-length hole blast holes 122 and the horizontal medium-length hole blast holes 123, performing ore caving by using an intra-row differential blasting method, wherein the delay interval time is 25-75 ms; the blasting sequence is that the blast holes at two sides are blasted in sequence in the row according to the middle blast hole. The bottom pillar recovery is carried out by adopting the medium-length hole differential blasting method, the impact force after the differential blasting is small, the damage to a filling body is reduced, the dilution rate of ore after ore removal is reduced, the mining quality is improved, and meanwhile, the safety of the bottom pillar recovery process is improved.
In a specific embodiment of the present application, a small-face rock drilling roadway 121 is tunneled in the triangular large pillars 12 inside the unit stopes 100; constructing upward medium-length hole blast holes 122 and horizontal medium-length hole blast holes 123 in the small-section rock drilling roadway 121; and (4) carrying out charging and blasting work on the blast hole, and carrying out high-strength filling on the unit stope after ore removal of the caving ore. Wherein, the hole bottom distance of the upward medium-length hole blast holes 122 is 2.0 m. The blasting adopts a row-inside differential blasting method, and the delay interval time is 50 ms; the blasting sequence is that the blast holes at two sides are blasted in sequence in the row according to the middle blast hole. And (4) recovering the large triangular pillar 12 by adopting the same method, and finally recovering the large triangular pillar 12 in the bottom structure in the whole medium-length hole stope.
The working principle of the utility model is as follows:
firstly, respectively tunneling rock drilling roadways 11 at the bottoms of two sublevel stopes 1 of a plurality of unit stopes 100, wherein the distance between the central axes of the two rock drilling roadways 11 of each unit stope 100 is greater than the width of the single sublevel stope 1, and then, normally blasting and mining the stopes by adopting upward medium-length hole blast holes; after mining is finished and filling is finished, a large triangular pillar 12 is formed in the middle of the unit stope 100; a small-section rock drilling roadway 121 is dug in the middle of the large triangular ore column 12, upward medium-length hole blast holes 122 are constructed in the small-section rock drilling roadway 121, and a stope bottom structure easy to recover is formed; finally, charging and blasting the blast holes 122 of the upward medium-length holes, and performing auxiliary ore removal by using the drift ore removal roadway 2 and the middle-section transportation flat roadway 3; all unit stopes 100 are recovered by the same method until all the pillars left in the stopes of the whole panel are mined. According to the utility model, the quantity of the bottom pillars needing to be recovered in the subsequent engineering is reduced by changing the bottom structure of the medium-length hole stope, only one bottom pillar needs to be recovered in every two stopes, the quantity of mining and cutting engineering is reduced, and the recovery rate of the bottom pillars is improved; and the stability and the security of big base pillar are higher.
Although the present invention has been described in detail with reference to the preferred embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the spirit and scope of the present invention.
Claims (10)
1. The bottom structure of the medium-length hole stope easy to recover is characterized by comprising a plurality of adjacent unit stopes (100), wherein each unit stope (100) comprises two adjacent sectional stopes (1) which are distributed in mirror symmetry, a rock drilling roadway (11) which is respectively arranged at the bottoms of the two sectional stopes (1) and a large triangular ore pillar (12) between the two rock drilling roadways (11); the two rock drilling roadways (11) are respectively and closely attached to two boundaries of the unit stope (100) and are distributed in a mirror symmetry mode;
big ore pillar of triangle (12) including middle bottom set up small section rock drilling tunnel (121), by small section rock drilling tunnel (121) to a plurality of upward medium-length hole blast holes (122) and horizontal medium-length hole blast hole (123) that the free surface of big ore pillar of triangle (12) extends, it is right to realize the recovery of big ore pillar of triangle (12).
2. The bottom structure of an easily recoverable medium-length hole stope according to claim 1, wherein the small-section rock drilling roadway (121) and the rock drilling roadway (11) are arranged along the trend of an ore body of the stope and are arranged in parallel.
3. The easy-to-recover medium-length hole stope bottom structure according to claim 1, wherein the upward medium-length hole blast holes (122) and the horizontal medium-length hole blast holes (123) are maintained in the same row with a row spacing of 2.2-2.8 m in the extending direction of the small-section rock drilling roadway (121).
4. The bottom structure of the easily-recycled medium-length hole stope is characterized in that the upward medium-length hole blast holes (122) are distributed in a fan-shaped structure on the same row plane, and the hole bottom distance between the upward medium-length hole blast holes and the horizontal medium-length hole blast holes (123) is 2-3 m.
5. The bottom structure of the medium-length hole stope easy to recycle according to claim 4, wherein the hole bottom distance between a plurality of the upward medium-length hole blast holes (122) in the same row is 2.0-2.5 m.
6. The easy-to-recover medium-length hole stope bottom structure according to claim 1, wherein the sublevel stope (1) is further provided with a high-strength filling body in the outside space of the free surface of the large triangularly-shaped ore pillar (12) and the rock drilling roadway (11).
7. The bottom structure of the medium-length hole stope easy to recover according to the claim 1, wherein a vein-through ore removal roadway (2), a middle transportation flat roadway (3), a ore pass communication roadway (4) and an ore pass shaft (5) are further arranged in the unit stope (100).
8. The bottom structure of the medium-length hole stope easy to recover is characterized in that the drift ore removal roadway (2) is communicated with the rock drilling roadway (11) of the adjacent sublevel stope (1), so that the ore removal is convenient during normal mining.
9. The bottom structure of an easily recoverable medium-length hole stope according to claim 7, wherein the middle-length hole transportation flat roadways (3) are arranged in two groups and are respectively arranged at the front end and the rear end of the bottom of the medium-length hole stope, and the middle-length hole transportation flat roadways (3) are arranged perpendicular to the rock drilling roadway (11).
10. The bottom structure of the easy-to-recover medium-length hole stope is characterized in that the included angle between the through-vein ore removal roadway (2) and the rock drilling roadway (11) is 40-50 degrees, and the distance between two adjacent through-vein ore removal roadways (2) is 10-12 m.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202220125638.8U CN216741503U (en) | 2022-01-18 | 2022-01-18 | Bottom structure of medium-length hole stope easy to recycle |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202220125638.8U CN216741503U (en) | 2022-01-18 | 2022-01-18 | Bottom structure of medium-length hole stope easy to recycle |
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