CN111854551A - A kind of micro-perturbation non-cutting blasting method - Google Patents

Abstract

A micro-disturbance non-cutting blasting method, which is used for the approach mining of weak and broken narrow ore veins, comprises the following steps: 1. Determine the position of the main weak structural surface of the tunnel face through measurement and data analysis; 2. Slot holes shall be drilled on both sides or one side of the structural surface, and peripheral holes shall be drilled on the periphery of the face; 3. After the upper layered approach is recovered, a buffer layer with a thickness of 10-20cm is laid on the bottom plate; 4. In the mining approach Reserve 10-20cm of retaining wall mines on both sides of the battery; 5. Use full-hole charge; 6. Use reverse differential detonation. Through the implementation of the above steps, the damage degree of blasting vibration to the upper layered cemented filling layer and the surrounding rock of the upper and lower walls is fundamentally solved, and the difficulty and cost of later support are effectively reduced. The invention utilizes the weak structure of the rock mass itself as a free surface, and reserves wall mines on both sides of the mining approach, which greatly reduces the number of blastholes arranged, thereby greatly reducing the construction amount of openings and the consumption of explosives. Improve the overall mining efficiency.

Description

A kind of micro-perturbation non-cutting blasting method

technical field

The invention relates to the field of underground mine blasting, in particular to a micro-disturbance non-cutting blasting method, which is mainly suitable for approach mining of weak and broken narrow ore veins.

Background technique

When mining weak and broken narrow ore veins, the commonly used mining methods are the upward approach filling mining method, the downward approach filling mining method and the upward horizontal layered filling mining method. Among them, the downward approach filling mining method has the highest proportion of ore out. No matter what kind of approach and filling method is used for mining, it is necessary to excavate hollow holes and undercut holes during rock drilling and blasting, and blast them with full-hole charge. Due to the large vibration of blasting, the crushing degree of the surrounding rock of the upper and lower walls, which is weak and broken, will be intensified, and the cost and difficulty of stope support will be further increased, resulting in an increase in the entire recovery cost, which indirectly reduces the overall benefit of the enterprise.

There are two main ways to reduce blasting vibration: smooth blasting and pre-split blasting. Usually, a large number of peripheral holes need to be excavated. Although blasting vibration is reduced, the whole construction process is more complicated, which seriously slows down the construction progress and reduces the recovery rate. . The patent with the authorization number of CN 103628878 B discloses a method for backfilling and mining of a broken surrounding rock ore body with a downward approach layered and non-segmented roadway. For the special condition of a sloping and thin ore body with a thickness of less than 5m, a non-cutting method is adopted. Differential blasting technology, that is to use the top reserved crushing cushion and the working face as the blasting free surface, to achieve non-cutting blasting, but the specific implementation method has not been announced, and it is only suitable for reserved crushing above the mining approach. Downward approach mining method of mine cushion. The patent application publication number CN109443117 A discloses a process for blasting a deep hole without cutting into a well, which is essentially a method of straight-tube cutting, that is, a deep hole with a diameter of 600mm needs to be constructed as a free surface first, and then the surrounding blastholes are successively drilled. Hole blasting to achieve one-time well formation. None of the above methods or methods can efficiently and cost-effectively solve the approach mining of weakly broken narrow ore veins.

SUMMARY OF THE INVENTION

In order to overcome the deficiencies in the background technology, the present invention discloses a micro-disturbance non-cutting blasting method, the purpose of which is to provide a method that can efficiently And the method of low-cost realization of weakly broken narrow ore vein approach mining.

For realizing the above-mentioned purpose of the invention, the present invention adopts following technical scheme:

A micro-disturbance non-undercut blasting method, which is used for the approach mining of weakly broken narrow ore veins, comprises the following steps:

S1: Determine the position of the main weak structural surface of the face through measurement and data analysis;

S2: dig slotted holes on both sides or one side of the weak structural surface, and dig peripheral holes on the periphery of the face, wherein the digging depth of the slotted holes is greater than the digging depth of the peripheral holes;

S3: After the upper layer is recovered, a buffer layer with a thickness of 10-20cm is laid on the bottom plate to reduce the damage of the lower layer mining vibration to the upper layer cemented backfill;

S4: Reserve 10-20cm of retaining wall ore on both sides of the mining approach as a buffer protection layer for the surrounding rocks on both sides;

S5: Use full-hole charge, and use plugs to block the slotted holes and the blastholes on the peripheral holes;

S6: The reverse differential detonation is used, the slotted hole is detonated first, and then the peripheral hole is detonated.

To further improve the technical solution, in S1, use a compass and a tape measure to measure the position of the main weak structural surface of the face.

To further improve the technical solution, in S2, when the weak structure surface is close to one side of the upper and lower plates or the top and bottom plates of the working surface, a slotted hole is drilled on the inner side of the weak structure surface; when the weak structure surface is located at the center of the working surface When in position, a slotted hole is drilled on both sides of the weak structural surface.

Further improving the technical solution, in S2, the excavation depth of the slotted hole is 0.2m deeper than the excavation depth of the peripheral hole.

Further improving the technical scheme, the diameter of the peripheral hole and the slotted hole is 28-30mm, and the diameter of the medicine roll is 27mm.

To further improve the technical solution, in S3, the buffer layer is composed of ore, or collapsed gravel, or a mixture of the two.

To further improve the technical solution, in S4, the retaining wall ore is mined and recovered by an air pick or other machinery after blasting.

To further improve the technical solution, in S5, the blockage is waste paper, or taphole mud, or a wooden stick.

To further improve the technical solution, in S6, the time difference of the differential detonation is millisecond level.

Due to adopting the above-mentioned technical scheme, compared with the background technology, the present invention has the following beneficial effects:

1. Small amount of opening construction and low consumption of explosives

The invention utilizes the weak structure of the rock mass itself as a free surface, and no longer specially cuts the cutting holes; reserves wall mines on both sides of the mining approach, reducing the number of blast holes arranged. These measures greatly reduce the construction volume of openings and the consumption of explosives.

2. The blasting vibration is small, and the difficulty and cost of later support are low

By setting the blasting buffer layers on both sides and the top of the mining approach, the invention reduces the damage degree of blasting vibration to the upper layered cemented filling layer and the surrounding rock of the upper and lower walls, thus effectively reducing the difficulty and cost of later support .

3. Conducive to the mining of ore

While ensuring the reduction of blasting vibration, the invention increases the degree of blasting to the wall-protecting ore through the full-hole charging of the peripheral holes, so as to cooperate with the later mining of the wall-protecting ore by machinery.

Description of drawings

FIG. 1 is a schematic diagram of a typical application of the present invention in Embodiment 1. FIG.

FIG. 2 is a schematic top-view cross-sectional structural diagram of FIG. 1 .

FIG. 3 is a schematic diagram of a typical application of the present invention in Embodiment 2. FIG.

In the figure: 1. The upper layer of cemented filling layer; 2. The buffer layer; 3. The retaining wall; 4. The bottom hole; 5. The weak structure surface;

Detailed ways

Preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principle of the present invention, and are not intended to limit the protection scope of the present invention.

Example 1:

A micro-disturbance non-undercut blasting method, which is used for the approach mining of weakly broken narrow ore veins, comprises the following steps:

S1: Determine the position of the main weak structural surface 5 of the face through measurement and data analysis.

During rock drilling, according to the development of face joints and fissures, find the main weak structural planes5. As shown in Fig. 1-2, the weak structural surface 5 is an inclined band-shaped surface, which is located in the middle part of the face of the tunnel. Use the compass and tape measure to measure the position of the main weak structure surface 5 of the face, and measure the tendency of the weak structure surface 5 through the compass, and obtain the trend of the weak structure surface 5 after adding or subtracting 90°.

S2: A slotted hole 6 is drilled on both sides of the weak structural surface 5, and a peripheral hole 7 is drilled on the periphery of the face.

As shown in Figure 2, according to the size of the palm face and the development of the weak structure surface 5, according to the principle of the minimum resistance line, the peripheral hole 7 is set to be 30~40cm away from the weak structure surface 5, and the distance from the arm guard mine 3 is 15~20cm . In this embodiment, the peripheral hole 7 is 30 cm away from the weak structure surface 5 and 15 cm away from the arm guard mine 3 . There are 8 peripheral holes 7, including 3 bottom eye holes 4 located at the bottom of the palm face. The diameter of the peripheral hole 7 is 28 mm, and the diameter of the slotted hole 6 is 30 mm. Since the slotted hole 6 is blasted on an incomplete free surface, the utilization rate of the blasthole is low due to the limitation of the rock clamping operation. Generally, the utilization rate of the blasthole can only reach 80%-95%. Therefore, the slotted hole 6 It is necessary to be 0.2 m deeper than the peripheral hole 7 .

S3: After the upper layer approach is recovered, a buffer layer 2 with a thickness of 10 cm is laid on the bottom plate.

In order to obtain local materials and reduce costs, the buffer layer 2 is composed of a mixture of mined ore and caving gravel. After laying, a cemented filling body is laid on the buffer layer 2 to form a solid upper layered cemented filling layer 1 . The upper layer cemented backfill layer 1 provides reliable top protection for the recovery of the lower layer. Since the ore and gravel in the buffer layer 2 have a certain gap space, they can be used as a free surface during blasting to absorb the damage of the upper layered cemented filling layer 1 due to blasting vibration.

S4: Reserve 10cm of retaining wall mine 3 on both sides of the mining approach.

After the blasting, the blasting cracks of the peripheral hole 7 spread to the surrounding, which will damage the surrounding rocks on both sides of the upper and lower walls, thereby increasing the difficulty and cost of later support. The reserved retaining wall mine 3 plays a buffering protection role for the surrounding rock on both sides of the upper and lower walls, and protects it from large blasting damage. As for the retaining wall mine 3, cracks are generated due to the impact of blasting, which is beneficial to mining and recycling by air picks or other mining machinery.

S5: Use full-hole charging, and use plugs to block the blastholes on the slotted hole 6 and the peripheral hole 7.

The full-hole charge is used to increase the blasting energy of the explosive, and the required blasting energy and blasting effect can be achieved by using fewer blast holes. The blockage of the blast hole can be made of waste paper, mud, or wooden sticks.

S6: The reverse differential detonation is used, and the slotted hole 6 is detonated first, and then the peripheral hole 7 is detonated.

The time difference between the differential detonation is milliseconds. Because the blasting time interval between the adjacent blastholes is very short, the energy field generated by blasting of each blasthole has a great influence on each other. Setting the time difference of the differential detonation to millisecond level can not only improve the blasting effect, but also reduce the blasting seismic effect, shock wave and flying stone hazards. The weak structural surface 5 provides a free surface for the detonation of the slotted hole 6, and guides the directional blasting of the slotted hole 6. At the same time, the blasting crack generated after the detonation of the slotted hole 6 provides a free surface for the detonation of the peripheral hole 7, and guides the peripheral hole. 7 Directional blasting to finally form the desired blasting surface.

Example 2:

S1: Determine the position of the main weak structural surface 5 of the face through measurement and data analysis.

During rock drilling, according to the development of face joints and fissures, find the main weak structural planes5. As shown in FIG. 3 , the weak structure surface 5 is a nearly horizontal inclined band-shaped surface, which is close to the top of the face of the palm. Use the compass and tape measure to measure the position of the main weak structure surface 5 of the face, and measure the tendency of the weak structure surface 5 through the compass, and obtain the trend of the weak structure surface 5 after adding or subtracting 90°.

S2: A slotted hole 6 is drilled on the inner side of the weak structural surface 5, near the center of the face, and a peripheral hole 7 is drilled on the periphery of the face.

In this embodiment, according to the size of the face and the development of the weak structure surface 5, according to the principle of the minimum resistance line, the peripheral hole 7 is set to be 40 cm from the weak structure surface 5 and 20 cm from the arm guard mine 3. There are 8 peripheral holes 7, including 3 bottom eye holes 4 located at the bottom of the palm face. The diameter of the peripheral hole 7 is 28 mm, and the diameter of the slotted hole 6 is 30 mm. The slotted hole 6 needs to be 0.2 m deeper than the peripheral hole 7 .

S3: After the upper layer approach is recovered, a buffer layer 2 with a thickness of 20 cm is laid on the bottom plate.

Since the weak structural surface 5 is close to the top of the face, in order to reduce the damage of the upper cemented filling layer 1 due to blasting vibration, the laying thickness of the buffer layer 2 is appropriately increased.

S4: Reserve 20cm of retaining wall mine 3 on both sides of the mining approach.

Since the weak structural surface 5 extends along the lateral direction of the face, in order to reduce the damage of the blasting vibration to the surrounding rocks on both sides of the upper and lower walls, the thickness of the retaining wall mine 3 is appropriately increased.

Steps S5 and S6 are the same as those in Embodiment 1, and will not be repeated here.

Parts not detailed are prior art. Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, and substitutions can be made in these embodiments without departing from the principle and spirit of the invention and modifications, the scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims (9)

1. a micro-perturbation non-cutting blasting method is used for the approach mining of weakly broken narrow ore veins, it is characterized in that: comprise the following steps: S1: Determine the position of the main weak structural surface of the face through measurement and data analysis; S2: dig slotted holes on both sides or one side of the weak structural surface, and dig peripheral holes on the periphery of the face, wherein the digging depth of the slotted holes is greater than the digging depth of the peripheral holes; S3: After the upper layer is recovered, a buffer layer with a thickness of 10-20cm is laid on the bottom plate to reduce the damage of the lower layer mining vibration to the upper layer cemented backfill; S4: Reserve 10-20cm of retaining wall ore on both sides of the mining approach as a buffer protection layer for the surrounding rocks on both sides; S5: Use full-hole charge, and use plugs to block the slotted holes and the blastholes on the peripheral holes; S6: The reverse differential detonation is used, the slotted hole is detonated first, and then the peripheral hole is detonated. 2. A micro-perturbation non-cutting blasting method as claimed in claim 1, wherein in S1, a compass and a tape measure are used to measure the position of the main weak structural surface of the face. 3. a kind of micro-perturbation non-cutting blasting method as claimed in claim 1 is characterized in that: in S2, when the weak structure surface is close to one side of the upper and lower plates of the face or the top and bottom plates, in the weak structure surface A slotted hole is drilled on the inner side of the weak structure surface; when the weak structure surface is located at the center of the face, a slotted hole is drilled on both sides of the weak structure surface. 4. A kind of micro-disturbance non-cutting blasting method as claimed in claim 1, it is characterized in that: in S2, the cutting depth of the slotted hole is 0.2m deeper than the cutting depth of the peripheral hole. 5. A kind of micro-disturbance non-cutting blasting method as claimed in claim 1, it is characterized in that: the aperture of described peripheral hole and described slotted hole is 28-30mm, and the diameter of the coil of charge is 27mm. 6 . The micro-disturbance non-undercut blasting method according to claim 1 , wherein in S3 , the buffer layer is composed of ore, or collapsed gravel, or a mixture of the two. 7 . 7. A kind of micro-disturbance non-cutting blasting method as claimed in claim 1, it is characterized in that: in S4, described retaining wall ore is mined and recovered by air pick or other machinery after blasting. 8. A kind of micro-disturbance non-cutting blasting method as claimed in claim 1, it is characterized in that: in S5, described blockage is waste paper, or is tap mud, or is wooden stick. 9 . The micro-disturbance non-cutting blasting method of claim 1 , wherein in S6 , the time difference of the micro-difference initiation is millisecond. 10 .

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