Choling blasting method for position close to slope covering layer

Abstract

The invention relates to the technical field of formation of an open-pit-to-underground mine first mining covering layer, in particular to a slotting blasting method for the position close to a slope covering layer. According to the groove broaching blasting method based on the combination of the vertical medium-length hole and the fan-shaped medium-length hole, the influence effect of ground stress on rock breaking and throwing is fully considered when the cutting blasting meshes are arranged, the medium-length hole cutting blasting effect is improved, and the purpose of forming a fan-shaped cutting groove at a time is achieved; and on the premise that the groove broaching blasting effect and the groove broaching quality are guaranteed, the tunneling process amount of roadway cutting and the corresponding safety risk are greatly reduced, so that follow-up stoping blasting operation can be promoted to be normally carried out, and the construction safety coefficient and the working efficiency are improved.

Description

Technical Field

[0001] The invention relates to the technical field of first mining covering layer formation in an open-pit-to-underground mine, and in particular to a slotting blasting method near a slope covering layer. Background Art

[0002] The demand for mineral resources by enterprises is increasing day by day, and it is very important to improve the efficiency of mining. This year, many mining enterprises in my country have begun the transformation from open-pit to underground, which has also brought challenges to the upgrading of mining technology. For metal frame mining, no matter which mining method is used, blasting must be used for excavation and ore landing. Therefore, blasting is the top priority of metal mining.

[0003] At present, the mining theory of my country's existing mining industry is developing slowly as a whole, and the mining technology is single. In addition, the distribution of mineral resources is relatively scattered and buried deep. It is technically difficult to achieve mineral resources with high mining requirements. However, some mining companies only mine resources that are easy to mine on the surface, resulting in serious waste of resources. There are three main reasons for the occurrence of mine safety accidents in my country: first, the mining technology is backward, and the safety of the mining environment is difficult to guarantee; second, some managers in the mining industry want to obtain high economic benefits with low investment, and do not pay enough attention to safety issues and lack safety protection measures; third, the safety management model is backward, and the quality of the groove and the efficiency directly restrict the mining efficiency.

[0004] Especially in some mines with narrow and scattered ore bodies, in the process of using the bottom-pillarless staged caving method to drop the ore, cutting grooves and cutting shafts are arranged at the end of each approach for joint grooving to provide sufficient space for subsequent blasting, and certain effects have been achieved in the application of medium and deep hole blasting. However, due to the large number of cutting grooves and cutting shafts that need to be arranged due to the scattered frame, the cutting workload is significantly increased and the production efficiency is seriously restricted. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a slotting blasting method near the position of the slope cover layer, so as to achieve the technical effect of improving the slotting blasting effect of medium and deep holes and realizing one-time forming of fan-shaped cutting.

[0006] To achieve this technical purpose, the present invention adopts the following scheme: A slot blasting method near the overburden layer of the slope is carried out in the following steps: S1. Arrange vertically upward medium-deep holes in the groove area, use the trolley perforation data recording system to record the changes in various parameters, infer the changes in rock hardness of each rock layer, and obtain the thickness of different rock layers according to the depth indication device; S2. Obtain the degree of development of the cracks at the location to be grooved; determine the seam filling morphology and distribution of the interface between the cracks and the rock layer on the rock mass section vertical to the medium-deep hole, and depict the overall morphology of the rock layer on the mapping software based on the changes in the cracks in the medium-deep hole; S3. Arrange the lines inside the mining tunnel according to the distribution of medium and deep hole fractures and determine the corresponding hole network parameters; According to the medium-deep hole rock drilling data chart, before the rock drilling operation is officially carried out, at least one test medium-deep hole with the same depth as the slot hole is drilled in the top plate of the slotting roadway in the vertical direction to reflect the thickness of different rock layers in the stratum where the slotting roadway is located, and at the same time reflect the hardness change of the rock layer, which is used as the basis for the arrangement of the slotting hole network in the reverse direction; According to the layout diagram of the medium-long holes, a combination of vertical medium-long holes and fan-shaped medium-long holes is used. The vertical direction adopts a vertical arrangement to keep the rows of holes parallel in the vertical direction to be used as slot holes. The holes are arranged in a fan-shaped pattern on the left and right sides, in which the charge row and the supply row are arranged at intervals. During the drilling process, the center hole is drilled first, then other vertical medium-depth holes on the same row, and then all the fan-shaped medium-depth holes on both sides are drilled in sequence. When drilling the fan-shaped medium-depth holes, the rock drilling centers of the vertical medium-depth holes on the left and right sides are used as the rock drilling centers of the fan-shaped medium-depth holes. Each row of medium-depth holes is drilled in sequence, and the drilling results are inspected after the drilling is completed; S4. During blasting, the charge is charged in an upper and lower segmented manner. The medium-deep hole is divided into upper and lower parts according to the groove height, and the middle is filled with flame-retardant filling materials; S5. Blasting is carried out in the order of the middle, then the two sides, then the surroundings, and finally the two sides of the fan-shaped medium and deep holes. After the blasting, the slag is removed to expose the formed cutting groove, and a 3D scanner is used to scan and inspect the grooving effect.

[0007] Compared with the prior art, the preferred solution adopted by the present invention is: The present invention is based on a slotting blasting method combining vertical medium-deep holes with fan-shaped medium-deep holes, and based on the inductive effect of compensation space on blasting crack expansion discovered during engineering work. When laying out slotting blasting meshes, the influence of ground stress on rock crushing and throwing is fully considered, thereby improving the slotting blasting effect of medium-deep holes and achieving the purpose of forming a fan-shaped cutting groove at one time. The blasting method has a simple structure, a reasonable design layout, and a simple organization process, and can greatly save the excavation process volume and corresponding safety risks of the cutting tunnel under the premise of ensuring the slotting blasting effect and slotting quality, thereby promoting the normal progress of subsequent recovery blasting operations, improving the construction safety factor and work efficiency, improving the blasting effect, and improving the comprehensive benefits.

[0008] Further, the preferred embodiment of the present invention is: In step S3, when arranging holes, vertical parallel holes are used within a width of 1 m with the center line of the tunnel as the center, and fan-shaped medium-depth holes are used for two times of arranging holes.

[0009] In step S3, the medium and deep hole wiring is arranged at equal intervals, with a total of 5 rows and a row spacing of 0.5m, among which the odd-numbered rows are charging rows and the even-numbered rows are supply rows. The hole spacing between the 1st row and the 5th row is 500mm, and the hole spacing between the 2nd row and the bottom 4 rows is 250mm. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 The wiring plan layout diagram of the present invention; Figure 2 It is the layout diagram of medium-deep holes; No. 8 is a vertical medium-deep hole; Figure 3 It is the plan layout of vertical medium and deep holes; Figure 4 It is a schematic diagram of the charge structure; Figure 5 This is the time diagram of the detonation sequence of the medium-deep hole; Figure 6 This is a schematic diagram of the slag throwing direction; DETAILED DESCRIPTION

[0011] In order to fully understand the purpose, features and effects of the present invention, the following specific embodiments are provided. Figures 1 to 6 The present invention is described in detail with reference to the accompanying drawings, but the present invention is not limited thereto.

[0012] The present invention provides a slot blasting method near the slope cover layer. The arrangement of the medium-deep hole line and hole layout is arranged by comprehensively considering the geological and topographical factors and the influence of the medium-deep hole clamping effect on the rock crushing and throwing. It is conducive to making full use of the geological conditions and the deadweight factors of the rock to eliminate the clamping effect of the deep hole surrounding rock, thereby improving the blasting effect of the slot blasting and increasing the slot height. The specific contents are as follows: S1. During the tunnel excavation stage, the direction of the rock strata is continuously observed to determine the rock properties of the approach and to obtain a preliminary understanding of the basic conditions such as rock hardness in combination with the blasting effect. The data obtained guides the selection of various parameters for grooving. The positions of medium and deep holes are determined in the area to be grooved, and the changes in various parameters of the trolley perforation data recording system are used to infer the changes in the rock hardness of each rock layer, and the thickness of different rock layers is obtained based on the depth indication device.

[0013] S2. Obtain the degree of development of the cracks at the location where the groove is to be drawn; on the rock section perpendicular to the circumference of the medium-deep hole, determine the distribution of the interface between the cracks and the rock strata on the rock section perpendicular to the axial direction of the medium-deep hole based on the visible cracks on the free surface. Specifically, determine the morphology and distribution of the interface with the vertical medium-deep hole as the center, and depict the overall morphology of the rock strata on the mapping software based on the changes in the cracks in the medium-deep hole, including the thickness change, inclination, and direction of the interface.

[0014] S3. Arrange the lines inside the mining tunnel according to the distribution of medium and deep hole fractures and determine the corresponding hole network parameters. like Figure 4 As shown in the figure, according to the medium-deep hole rock drilling data chart, before the formal rock drilling operation is carried out, at least one vertically placed medium-deep hole for testing with the same depth as the slotting hole is drilled on the top plate of the slotting tunnel to reflect the thickness of different rock layers in the stratum where the slotting tunnel is located, and at the same time reflect the hardness change of the rock. In reverse, it serves as the basis for the arrangement of the slotting hole network to adapt to the rock structure and hardness characteristics of the tunnel, thereby helping to improve the blasting effect of medium-deep hole slotting.

[0015] like Figures 1 to 3 As shown, a combination of vertical medium-deep holes and fan-shaped medium-deep holes is used in hole arrangement. The vertical medium-deep holes in the same row are arranged in parallel as slot holes. The center line of the tunnel is used as the center when arranging holes. Vertical medium-deep holes are used within a width of 1m. The vertical medium-deep holes are arranged in equal rows, with a total of 5 rows and a row spacing of 0.5m. At the drilling site, surveyors use total stations to lay out the centerline coordinates on the design drawings using the determined control points. To ensure the accuracy of each line, a midpoint is required for each line. The total station is realigned using the placed midline point. The lines are marked on both sides of the tunnel according to their angles, and the corresponding row numbers are indicated. Among the 5 rows of vertical medium-deep holes, the 1st, 3rd and 5th rows are charge rows, and the drill diameter of the holes is 76mm. The 2nd and 4th rows are supply rows, and the drill diameter of the holes is 89mm. The spacing between the 1st and 5th rows of medium-deep holes is 500mm, and the spacing between the 2nd and 4th rows is 250mm. The 3rd row is used as a slot hole. In order to increase the charge amount, one 76mm drill hole and two 89mm drill holes are added. Sector-shaped medium-deep holes are set on the left and right sides of each row of holes, with a hole bottom distance of 1.5m and a side hole angle of 55°.

[0016] During the drilling process, drill the center hole first, then drill other vertical medium-depth holes in the same row, and then drill all the fan-shaped medium-depth holes on both sides in turn. When drilling the fan-shaped medium-depth holes, use the rock drilling center of the vertical medium-depth holes on the left and right sides as the rock drilling center of the fan-shaped medium-depth holes. Punch each row of medium-depth holes in turn. After the drilling is completed, inspect the drilling results to accurately grasp the depth and angle of each medium-depth hole.

[0017] S4, such as Figure 5 As shown, during blasting, the upper and lower sections are used for charging. The medium-deep hole is divided into upper and lower sections according to the groove height. During charging, the detonating bomb is sent to the bottom of the hole together with the drug delivery tube, and the charging trolley is started for charging. The operator keeps a close eye on the depth display on the instrument. When the depth of the drug delivery tube reaches the set depth, the charging is stopped, the drug delivery tube is retracted, and then the prepared flame-retardant filling material is placed on the end of the drug delivery tube. The flame-retardant filling material is sent to the set depth position along the drug delivery tube and then the drug delivery tube is retracted. Finally, the detonating bomb is installed for charging in the lower section. The detonating bomb is sent to the set depth in the same way to start charging. When the depth indicator shows that the drug delivery tube has reached the predetermined depth, the charging is stopped.

[0018] The flame retardant filling material in this embodiment is used to separate the upper and lower sections, so as to form a buffer zone between the upper and lower ends of the explosive columns to avoid the occurrence of sympathetic detonation between the explosive columns and affect the blasting effect.

[0019] S5. During blasting, if Figure 6 As shown in the figure, the blasting sequence is to blast the middle first, then the two sides, then the surroundings, and finally the two sides of the fan-shaped medium and deep holes are blasted in order to achieve the purpose of groove drawing. After blasting, the slag is removed to expose the formed cutting groove, and a 3D scanner is used to scan and inspect the groove drawing effect.

[0020] During blasting, the upper and lower ends of the medium-depth hole are detonated respectively. The lower section of the corresponding medium-depth hole will explode first, and the upper section will explode after a period of time. This allows the compensation space formed by the blasting throwing or natural falling of the slag after the blasting of the lower section to be utilized by the surrounding and upper sections, thereby improving the blasting effect.

[0021] According to public information, for medium-deep hole slot blasting, the clamping effect is large, resulting in the effective crushing range at the bottom of the hole being smaller than the hole mouth. Considering that the clamping force of the rock mass also affects the blasting effect of the blasthole, in order to reduce the impact of the clamping effect, the delay time of the medium-deep hole blasting should be changed. The delay time between adjacent medium-deep holes should be no less than 500ms, so that the slag after the blasting has sufficient time to be thrown or fall naturally under the action of gravity, thereby providing sufficient free space for the subsequent blasting hole.

[0022] In this embodiment, the number of slot holes often needs to be determined according to the actual engineering situation. When the number of slot holes increases or decreases, the slot holes can still be arranged in a rectangular pattern as the basis for modular medium and deep hole arrangement. In this way, the modular pattern can fully utilize the effective crushing range of the medium and deep holes without repeated design, thereby simplifying the design of the hole network parameters.

[0023] The present invention is based on a slotting blasting method combining vertical medium-deep holes with fan-shaped medium-deep holes, and based on the inductive effect of compensation space on blasting crack expansion discovered during engineering work. When laying out slotting blasting meshes, the influence of ground stress on rock crushing and throwing is fully considered, thereby improving the slotting blasting effect of medium-deep holes and achieving the purpose of forming a fan-shaped cutting groove at one time. The blasting method has a simple structure, a reasonable design layout, and a simple organization process, and can greatly save the excavation process volume and corresponding safety risks of the cutting tunnel under the premise of ensuring the slotting blasting effect and slotting quality, thereby promoting the normal progress of subsequent recovery blasting operations, improving the construction safety factor and work efficiency, improving the blasting effect, and improving the comprehensive benefits.

[0024] Finally, it should be noted that the above are only preferred embodiments of the present invention. Of course, those skilled in the art can make changes and modifications to the present invention. If these modifications and variations fall within the scope of the claims of the present invention and their equivalent technologies, they should be considered to be within the scope of protection of the present invention.

Claims

1. A slotting blasting method near the overburden layer of a slope, characterized in that: Follow these steps: S1. Arrange vertically upward medium-deep holes in the groove area, use the trolley perforation data recording system to record the changes in various parameters, infer the changes in rock hardness of each rock layer, and obtain the thickness of different rock layers according to the depth indication device; S2. Obtain the degree of development of the cracks at the location to be grooved; determine the seam filling morphology and distribution of the interface between the cracks and the rock layer on the rock mass section vertical to the medium-deep hole, and depict the overall morphology of the rock layer on the mapping software based on the changes in the cracks in the medium-deep hole; S3. Arrange the lines inside the mining tunnel according to the distribution of medium and deep hole fractures and determine the corresponding hole network parameters; According to the medium-deep hole rock drilling data chart, before the rock drilling operation is officially carried out, at least one test medium-deep hole with the same depth as the slot hole is drilled in the top plate of the slotting roadway in the vertical direction to reflect the thickness of different rock layers in the stratum where the slotting roadway is located, and at the same time reflect the hardness change of the rock layer, which is used as the basis for the arrangement of the slotting hole network in the reverse direction; According to the layout diagram of the medium-long holes, a combination of vertical medium-long holes and fan-shaped medium-long holes is used. The vertical direction adopts a vertical arrangement to keep the rows of holes parallel in the vertical direction to be used as slot holes. The holes are arranged in a fan-shaped pattern on the left and right sides, in which the charge row and the supply row are arranged at intervals. During the drilling process, the center hole is drilled first, then other vertical medium-depth holes on the same row, and then all the fan-shaped medium-depth holes on both sides are drilled in sequence. When drilling the fan-shaped medium-depth holes, the rock drilling centers of the vertical medium-depth holes on the left and right sides are used as the rock drilling centers of the fan-shaped medium-depth holes. Each row of medium-depth holes is drilled in sequence, and the drilling results are inspected after the drilling is completed; S4. During blasting, the charge is charged in an upper and lower segmented manner. The medium-deep hole is divided into upper and lower parts according to the groove height, and the middle is filled with flame-retardant filling materials; S5. Blasting is carried out in the order of the middle, then the two sides, then the surroundings, and finally the two sides of the fan-shaped medium and deep holes. After the blasting, the slag is removed to expose the formed cutting groove, and a 3D scanner is used to scan and inspect the grooving effect.

2. The method for blasting a slot near a slope cover layer according to claim 1, characterized in that: In step S3, when arranging holes, vertical parallel holes are used within a width of 1 m with the center line of the lane as the center, and fan-shaped medium-depth holes are used for two times of arranging holes.

3. The method for blasting a slot near a slope cover layer according to claim 1, characterized in that: In step S3, the medium and deep hole wiring is arranged at equal intervals, with a total of 5 rows and a row spacing of 0.5m. The odd-numbered rows are charging rows, and the even-numbered rows are supply rows. The hole spacing between the 1st and 5th rows is 500mm, the hole spacing between the 2nd row and the bottom 4 rows is 250mm, and two drill holes are added to the 3rd row.

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