Arrangement method of medium-length hole blasting well-forming blast holes capable of preventing top suspension

Abstract

The invention discloses a suspended roof prevention blast hole arrangement method for medium-length hole blasting well completion, relates to the field of medium-length hole blasting well completion, and mainly aims to reduce the suspended roof risk of medium-length hole blasting well completion and improve the operation efficiency. The blast holes including slotting holes and auxiliary inclined holes are distributed according to a designed drawing, punching, charging and detonating are conducted in sequence according to the steps provided by the invention for testing, the method is suitable for the raise with the well completion height ranging from 10 m to 16 m, cooperative operation of the blast hole arrangement structure and the charging structure is matched, and therefore the purposes of improving the field tunneling efficiency, reducing the construction cost and the like are achieved. And the engineering cost is saved, and the blasting well-forming suspended roof risk is reduced.

Description

Technical Field

[0001] The present invention relates to the field of medium-deep hole blasting for shaft sinking, and particularly to a method for arranging blast holes in medium-deep hole blasting for shaft sinking with anti-suspension roof applicable to the shaft sinking height in the range of 10-16m. Background Technique

[0002] Shaft construction is a key process in underground mining construction, and its formation speed, quality, and position all affect the application of mining methods. At present, shaft construction in underground mines in China is mainly divided into two categories: in-shaft construction and out-of-shaft construction. Among them, the in-shaft construction methods include the ordinary method, the hanging basket method, and the climbing basket method, and the out-of-shaft construction methods include the raise borer method and the blasting shaft sinking method. The ordinary method has complex technology, high labor intensity, and low efficiency; the shaft size is small, the cost is high, and the safety is poor; the raise borer method has good safety, can construct larger-sized shafts, and the shaft shape is regular, but the construction cost is relatively high, there are many equipment modules, and the labor intensity of equipment moving is large; the blasting shaft sinking method has good safety, high efficiency, can construct larger-sized shafts, low construction cost, and convenient equipment movement. However, due to the specific characteristics of the medium-deep hole blasting for shaft sinking process, such as small cut hole spacing and easy hole deviation, there will occasionally be a phenomenon of insufficient blasting height and the formation of a partition suspension roof.

[0003] Due to the instability of the roof of the rock drilling roadway after blasting, the rock mass near the shaft is prone to large deformation, and the drill holes may be damaged by blasting, affecting secondary charging; at the same time, it is impossible to confirm problems such as whether there is residual explosive in the suspension roof area, so the treatment of the suspension roof problem becomes extremely difficult.

[0004] To solve the above-mentioned suspension roof hidden danger existing in medium-deep hole blasting for shaft sinking construction, the present invention provides a method for arranging blast holes in medium-deep hole blasting for shaft sinking with anti-suspension roof. Summary of the Invention

[0005] In view of the above problems, the purpose of the present invention is to provide a method for arranging blast holes in medium-deep hole blasting for shaft sinking with anti-suspension roof to solve the suspension roof hidden danger existing in current medium-deep hole blasting for shaft sinking construction.

[0006] To solve the above technical problems, the technical solution of the present invention is: a method for arranging blast holes in medium-deep hole blasting for shaft sinking with anti-suspension roof, and the method specifically includes the steps:

[0007] S1) Delimit the shaft sinking area according to production requirements, and adjust the shaft sinking position according to the engineering geological conditions of the shaft sinking area;

[0008] S2) Clean the roadway according to the adjusted shaft sinking position in S1) until the hard bottom, then plaster with concrete with a thickness of 20-30 cm. After the concrete reaches a certain strength, use rock drilling equipment to drill holes on the concrete working platform, position the drilling points at the top of the roadway, and spray paint for marking at the drilling points;

[0009] S3) Open several blast holes in the well completion area, and load explosives into the blast holes respectively;

[0010] S4) Then place the explosive packages into the blast holes, install detonators between the explosive packages, and detonate them by the millisecond delay initiation method, and the raise is formed.

[0011] Further, the blast holes in the S3) include several cut holes and auxiliary inclined holes, and the diameters of the cut holes and the auxiliary inclined holes are both 80 - 120 mm;

[0012] And several cut holes are arranged in a square, and the hole spacing is not less than 300 mm;

[0013] And several auxiliary inclined holes are arranged in a circle, the hole spacing from the central cut hole is 724 mm, and the deviation of the hole shall not be greater than 0.5°.

[0014] Further, the number of the cut holes is 5 - 9, and the number of the auxiliary inclined holes is adjusted accordingly according to the raise specifications.

[0015] Further, the raise height in the S3) is H 1 , the cut hole height is H 2 , the length of the auxiliary inclined hole is H 3 ,

[0016] The vertical height H 4 of the auxiliary inclined hole are respectively:

[0017] Cut hole height: H 2 = H 1 - 0.3 m;

[0018] Length of the auxiliary inclined hole:

[0019] Vertical height of the auxiliary inclined hole: H 4 = 2 / 3 × H 2 .

[0020] Further, the charging method of the cut holes in the S3) adopts a segmented coupled charging structure, where the charging length of the upper segment of the cut hole is H 5 , blocked with stemming clay, the blocking length is 0.5 m, the charging length of the lower segment of the cut hole is H 6 , the hole mouth is blocked with a hard cardboard, the blocking length is 0.3 m; the charging length of the auxiliary inclined hole is H 7 .

[0021] Further, in the charging structure, the charging length of the upper segment of the cut hole is H 5 , the charging length of the lower segment of the cut hole is H 6 and the charging length of the auxiliary inclined hole is H 7 are respectively:

[0022] Length of the upper segmented charge in the cut hole: H 5 = 0.4×(H 2 - 0.8 m);

[0023] Length of the lower segmented charge in the cut hole: H 6 = 0.6×(H 2 - 0.8 m);

[0024] Length of the charge in the auxiliary inclined hole: H 7 = 0.5×H 3 .

[0025] Furthermore, for the detonator installation in the step S4): when the length of the upper segmented charge (H 5 ) ≥ 5.5 m, two electronic detonators are used for detonation, and the electronic detonators are respectively installed in the second charge package and the second-to-last charge package; when the length of the upper segmented charge (H 5 ) < 5.5 m, a single electronic detonator is used for detonation, and the electronic detonator is installed in the charge package at the middle of the segmented height.

[0026] Furthermore, the initiation sequence in the step S4) needs to satisfy the relational expression of the rock swelling coefficient and the compensation space, that is:

[0027]

[0028] In the formula: S n - Blasted rock mass;

[0029] S m - Compensable space that can be provided;

[0030] k - Rock swelling coefficient.

[0031] The advantage of the method for arranging blast holes for medium-deep hole blasting to form a shaft with anti-suspension roof proposed by the present invention is that auxiliary inclined holes are added around the cut holes to achieve the effect of reducing the risk of suspension roof during the construction of blasting to form a shaft. The present invention is applicable to shafts with a shaft-forming height in the range of 10 - 16 m. After the lower segment and the upper segment of the cut holes are blasted in sequence, blasting funnels are formed downward and upward in the shaft-forming area. If a suspension roof phenomenon occurs in the middle part of the shaft, after sufficient slag throwing, the charged part of the auxiliary inclined holes is blasted, and oblique extrusion is generated to break the rock in the suspension roof part, and the shaft is penetrated, so as to achieve the effect of realizing medium-deep hole blasting to form a shaft, improving the on-site tunneling efficiency, enhancing the construction safety, saving the project cost, and reducing the risk of suspension roof in blasting to form a shaft.

[0032] In order to achieve the above and related purposes, one or more aspects of the present invention include the following detailed descriptions. Through the following drawings and embodiments, the present invention will be further described in detail. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is the cross-sectional view of the blast holes arrangement for medium-deep hole blasting and shaft sinking to prevent roof suspension in the present invention;

[0034] Figure 2 This is the layout diagram of the blast holes for medium-deep hole blasting and shaft sinking to prevent roof suspension in the present invention;

[0035] Figure 3 This is the charge structure diagram of the cut holes;

[0036] Figure 4 This is the charge structure diagram of the auxiliary inclined holes;

[0037] Figure 5 This is the schematic diagram of the staged initiation network;

[0038] Figure 6 This is the schematic diagram of the compensation space.

[0039] In the figure:

[0040] 1. Cut holes; 2. Auxiliary inclined holes; 3. Surrounding rock; 4. Tunnel; 5. Upper section of the cut holes; 6. Cartridge; 7. Stemming; 8. Lower section of the cut holes; 9. Industrial electronic digital detonator; 10. Leg wire; 11. Hard paper shell; 12. Hole mouth; 13. Charge part of the auxiliary inclined holes; 14. Rock mass to be blasted. Specific implementation manner

[0041] Aiming at the problem of roof suspension hidden danger existing in the medium-deep hole blasting and shaft sinking construction proposed above, the present invention provides a blast hole arrangement method for medium-deep hole blasting and shaft sinking to prevent roof suspension.

[0042] The following will describe in detail the specific embodiments of the present invention with reference to the accompanying drawings. The blast hole arrangement method for medium-deep hole blasting and shaft sinking to prevent roof suspension described above is used in the shaft construction of underground mines, and includes the following steps:

[0043] (1) Determine the position: delimit the shaft sinking area according to production requirements, and adjust the shaft sinking position according to the engineering geological conditions of the shaft sinking area; select harder rock mass for construction, which helps to effectively reduce the drilling deviation rate;

[0044] (2) Preliminary preparation: clean the tunnel until the hard bottom according to the shaft sinking position, lay a concrete plaster with a thickness of 20 - 30 cm on the construction area, and after the concrete reaches a certain strength, the rock drilling equipment can drill holes on the concrete working platform; position the drilling points on the top of the tunnel and mark them with paint;

[0045] (3) Drilling construction: use a rock drilling jumbo for drilling construction, open 17 blast holes in the shaft sinking area, the diameter of all blast holes is 100 mm, including 9 cut holes and 8 auxiliary inclined holes, the shaft sinking height is H 1 , the height of the cut holes is H 2 , the length of the auxiliary inclined holes is H 3, where 9 cut holes are arranged in a square, and the cut hole numbers are: Blast Hole 0# to Blast Hole 8#, the hole spacing is 300 mm, 8 auxiliary inclined holes are arranged in a circle, and the auxiliary inclined hole numbers are: Blast Hole 9# to Blast Hole 16#, and the hole spacing from the central cut hole is 724 mm, and the vertical height of the auxiliary inclined hole is H 4 , the deviation of the drilling shall not be greater than 0.5°, the cross-sectional view of the blast hole arrangement is shown in Figure 1, and the layout plan of the blast hole is shown in Figure 2;

[0046] Cut hole height: H 2 =H 1 -0.3 m;

[0047] Length of the auxiliary inclined hole:

[0048] Vertical height of the auxiliary inclined hole: H 4 =2 / 3×H 2 .

[0049] (4) Charging structure: The cut holes adopt a segmented coupled charging structure, where the charging length of the upper segment of the cut hole is H 5 , and it is blocked with gun mud, and the blocking length is 0.5 m. The charging length of the lower segment of the cut hole is H 6 , and the orifice is blocked with a hard cardboard shell, and the blocking length is 0.3 m. The charging structure diagram of the cut hole is shown in Figure 4; The charging length of the auxiliary inclined hole is H 7 , and it is blocked with a hard cardboard shell to prevent the medicine package from falling. The charging structure diagram of the auxiliary inclined hole is shown in Figure 5;

[0050] Charging length of the upper segment of the cut hole: H 5 =0.4×(H 2 -0.8 m);

[0051] Charging length of the lower segment of the cut hole: H 6 =0.6×(H 2 -0.8 m);

[0052] Charging length of the auxiliary inclined hole: H 7 =0.5×H 3 .

[0053] (5) Detonator installation: When the charging length of the upper segment (H 5 )≥5.5 m, it is detonated with double electronic detonators, and the electronic detonators are respectively installed in the second medicine package and the second-to-last medicine package; When the charging length of the upper segment (H 5 )<5.5 m, it is detonated with a single electronic detonator, and the electronic detonator is installed in the medicine package in the middle of the segmented height;

[0054] (6) Initiation sequence: Millisecond initiation is adopted. The cut holes are blasted in two segments (hole 0#, hole 1# → hole 2# → hole 3#, hole 4# → hole 5# to hole 8#) → the upper segments of the cut holes are blasted (hole 0#, hole 1# → hole 2# → hole 3#, hole 4# → hole 5# to hole 8#) → the auxiliary inclined holes are blasted (hole 9# to 16#). According to the height of the compensation space and the movement law of the blasted and broken rock slag, a reasonable delay blasting time is determined, and an industrial electronic digital detonator network is used for initiation;

[0055] (7) Cleaning of slag after blasting: After blasting is completed and sufficient ventilation is carried out, the loose rock on the top of the surrounding roadways in the blasted area is cleaned. After the surrounding rock mass is stable, the forklift can enter for slag cleaning, and then the quality of the raise formed can be observed.

[0056] Examples of the present invention:

[0057] The test site is the section from -187m to -170m in a certain underground mine. The height of the raise formed is 13.6m, among which the height of the cut holes is 13.3m, the length of the charged inclined holes is 8.87m, among which the charged length of the upper segments of the cut holes is 4.88m, and a single electronic detonator is used for initiation. The charged length of the lower segments of the cut holes is 7.32m, and a double electronic detonator is used for initiation. The charged length of the charged inclined holes is 4.44m; among which the schematic diagram of the segmented initiation network is as Figure 5 shown. According to the hole layout structure and the initiation sequence, the compensation space is calculated. The obtained compensation space calculation table is shown in Table 1, and the schematic diagram of the compensation space is as Figure 6 shown.

[0058] Table 1 Compensation space calculation table

[0059]

[0060] This test method provides a new approach for the construction of medium-deep hole blasting raises in underground mines, and provides a strong guarantee for the effect of preventing roof suspension in medium-deep hole blasting raises.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the present invention and do not limit the technical solutions described in the present invention; therefore, although this specification has described the present invention in detail with reference to the above-mentioned various embodiments, those of ordinary skill in the art should understand that the present invention can still be modified or equivalently replaced; and all technical solutions and their improvements that do not depart from the spirit and scope of the present invention should be covered within the scope of the claims of the present invention.

Claims

1. A method for arranging blastholes for medium-deep hole blasting to prevent overhanging roof, characterized in that: The method specifically comprises the steps of: S1) Delineate the well drilling area according to production needs and adjust the well drilling location according to the engineering geological conditions of the well drilling area; S2) Clean the tunnel according to the well position adjusted in S1) until the hard bottom, then apply concrete plastering with a thickness of 20 to 30 cm. After the concrete reaches a certain strength, use rock drilling equipment to drill holes on the concrete working platform, locate the drilling points at the top of the tunnel, and spray paint on the drilling points for marking; S3) opening a plurality of blast holes in the well formation area and respectively loading explosives in the blast holes; S4) placing the explosive packs in the blastholes, installing detonators between the explosive packs, and detonating them by micro-difference detonation to obtain a raised well.

2. The method according to claim 1, characterized in that: The blastholes in S3) include a plurality of slotted holes and auxiliary inclined holes, and the apertures of the slotted holes and the auxiliary inclined holes are both 80-120 mm; And several slotted holes are arranged in a square shape, with a hole spacing of no less than 300mm; And several auxiliary inclined holes are arranged in a circle, the spacing between the slot holes from the center is 724mm, and the deviation of the holes shall not exceed 0.5°.

3. The method according to claim 2, characterized in that: The number of the slot holes is 5-9, and the number of the auxiliary inclined holes is adjusted accordingly according to the well drilling specifications.

4. The method according to claim 2, characterized in that: The well height in S3) is H1, the slot hole height is H2, and the auxiliary inclined hole length is H3. The vertical heights H4 of the auxiliary inclined holes are: Grooving hole height: H2 = H1-0.3m; Auxiliary inclined hole length: Vertical height of auxiliary inclined hole: H4=2 / 3×H2.

5. The method according to claim 2, characterized in that: The charging method of the slot hole in S3) adopts a segmented coupled charging structure, wherein the upper segmented charging length of the slot hole is H5, and it is blocked with gun mud with a blocking length of 0.5m; the lower segmented charging length of the slot hole is H6, and the hole mouth is blocked with cardboard with a blocking length of 0.3m; the charging length of the auxiliary inclined hole is H7.

6. The method according to claim 5, characterized in that: In the charging structure, the length of the upper segmented charging of the slot hole is H5, the length of the lower segmented charging of the slot hole is H6, and the length of the charging of the auxiliary inclined hole is H7, respectively: Length of segmented charge on the slot hole: H5 = 0.4 × (H2-0.8m); Length of segmented charge under the slot hole: H6 = 0.6 × (H2-0.8m); Auxiliary inclined hole charging length: H7 = 0.5 × H3.

7. The method according to claim 5, characterized in that: The detonator installation in S4) is as follows: when the upper segment charge length (H5) is ≥5.5m, double electronic detonators are used for detonation, and the electronic detonators are respectively installed in the second section charge and the penultimate section charge; when the upper segment charge length (H5) is <5.5m, single electronic detonator is used for detonation, and the electronic detonator is installed in the charge at the middle of the segment height.

8. The method according to claim 1, characterized in that: The detonation sequence of the micro-difference detonation method in S4) must satisfy the relationship between the rock expansion coefficient and the compensation space, that is: Where: S n - blasting rock mass; S m - Compensation space can be provided; k-rock expansion coefficient.

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