Water coupling presplitting blasting charging structure and blasting method thereof

Abstract

The invention discloses a water-coupled presplitting blasting charging structure and a blasting method thereof.The bottom of a blasting hole is filled with mixed explosives tightly attached to the hole wall of the blasting hole to form a charging section, a primer detonator is pre-buried in the charging section to detonate the mixed explosives, and a detonator leg wire of the primer detonator is led out of the blasting hole to be connected with a detonating network; a water coupling section is formed by injecting water into a blast hole in the charging section, the top of the water coupling section is filled with stemming to seal an orifice of the blast hole, a filling section is formed, impact energy generated after the charging section is detonated is stably attenuated in the water coupling section, formation of a rock mass along a set pre-crack is promoted, and excess energy is absorbed to avoid excessive damage to other rock mass directions. The water coupling presplitting blasting charging structure suitable for the mixed charging truck is adopted during presplitting blasting, the charging structure is simple, the characteristic that shock waves generated by explosives are slow in attenuation in water is fully utilized, the blasting cost is reduced, the success rate of presplitting blasting forming is increased, the production efficiency is improved, and good economic benefits are achieved.

Description

Technical Field

[0001] The invention discloses a water-coupled pre-splitting blasting charge structure and a blasting method thereof, belonging to pre-splitting blasting engineering technology. Background Art

[0002] In the actual production process of mines, pre-splitting blasting is a commonly used controlled blasting method. Its main function is to form pre-cracks before the main blasting to achieve the effect of reducing blasting vibration. The existing pre-splitting blasting process adopts a continuous charging structure, and the pre-splitting blasting blasthole is filled with explosives except for the filling length. This leads to high explosive consumption and high blasting vibration intensity, which easily causes excessive damage to the surrounding rock mass. In addition, most pre-splitting blasting operations currently use packaged emulsion explosives for charging, resulting in gaps between the explosives in the axial and radial directions of the blasthole, which in turn affects the effect of pre-splitting blasting. At the same time, the charging process requires manual operation, which leads to long operation time, high labor intensity and low work efficiency. Summary of the Invention

[0003] The technical problem solved by the present invention is to provide a water-coupled pre-splitting blasting charging structure and a blasting method thereof in view of the problem that the existing pre-splitting blasting adopts a continuous charging structure and the pre-splitting blasting effect is poor.

[0004] The present invention is implemented by the following technical solutions: The present invention first discloses a water-coupled pre-splitting blasting charge structure, wherein the bottom of the blasting blasthole is closely attached to the blasthole wall and filled with mixed explosives 1 to form a charge section, wherein a detonating cap 4 is pre-buried in the charge section, and a detonator leg line of the detonating cap 4 is led out of the blasthole, and a water-coupled section is provided for the blasthole on the charge section, and the top of the water-coupled section to the blasthole mouth is filled with gun mud to seal it.

[0005] In the water-coupled pre-splitting blasting charge structure disclosed in the present invention, further, the mixed explosive 1 is prepared by mixing a hydrophobic oil phase material with the explosive.

[0006] In a water-coupled pre-splitting blasting charge structure disclosed in the present invention, further, the water-coupled section is surrounded by the charge section at the bottom of the blasthole and the blasthole wall to form a container, and water is directly injected into the blasthole to form the water-coupled section.

[0007] In the water-coupled pre-splitting blasting charge structure disclosed in the present invention, further, the detonator is an electronic detonator.

[0008] In a water-coupled pre-splitting blasting charge structure disclosed in the present invention, further, the length of the filling section is 9-12% of the length of the blasting hole, the length of the water-coupling section is 63-71% of the length of the blasting hole, and the length of the charging section is 20-25% of the length of the blasting hole.

[0009] The present invention also discloses a blasting method using the water-coupled pre-splitting blasting charge structure, which specifically comprises the following steps: S1. Use a drilling rig to drill blast holes in the pre-splitting blasting area and clean impurities in the blast holes before charging; S2. Placing a blasting cap as an active detonating component at the bottom of the blasting hole, leading the detonator leg wire connected to the blasting cap out of the blasting hole, and using a mixing truck to fill the mixed explosives to the bottom of the blasting hole to form a charging section; S3, injecting water into the blasting hole on the charging section to form a water coupling section, and filling the blasting hole with mud from the top of the water coupling section to the blasting hole mouth to seal the blasting hole; S4. Complete the charging of all blasting holes in the pre-splitting blasting area according to steps S2 and S3, and connect the detonator legs from all blasting holes to the initiation network for initiation.

[0010] The pre-splitting blasting charge structure adopted by the present invention adopts mixed explosives for charging, and is combined with a water-coupled charge structure. Water is filled on the charging section to form a water-coupled section. During the blasting process, the impact energy generated after the charging section is detonated is stably attenuated in the medium water of the water-coupled section, reducing the blasting energy, promoting the precise formation of pre-cracks, and reducing the excessive damage of the blasting impact energy to the surrounding rock mass.

[0011] The above technical solution provided by the present invention has the following beneficial effects: (1) The pre-splitting blasting charge structure of the present invention is suitable for mixed loading vehicle charging. The charge structure is simple and multiple blast holes can be directly filled with mixed explosives by the mixed loading vehicle. The water coupling section is formed by directly injecting water into the blast hole. The operation process is simple, which effectively improves the efficiency of blasting charge and improves the economic benefits of the mine.

[0012] (2) The present invention reduces the charging height of the mixed explosives by arranging a water coupling section above the charging section, saves blasting costs, and improves the economic benefits of the mine.

[0013] (3) Compared with the traditional pre-splitting blasting charge structure, the charge section formed by the mixed explosives used in the present invention can directly fill the blasthole with the mixed explosives close to the blasthole wall. There is no gap between the explosive section and the blasthole wall, and the blasting energy is more direct. At the same time, the shock wave generated by the explosive is fully utilized. The slow attenuation of the shock wave in water can be fully utilized. The impact energy can more effectively impact and destroy the rocks on both sides of the blasthole, promote the formation of pre-cracks between the blasting blastholes, and the water-coupled charge structure can protect the rock mass in other directions of the blasthole from excessive damage.

[0014] In summary, the water-coupled pre-splitting blasting charge structure and blasting method of the present invention utilize mixed explosives for charging during pre-splitting blasting, and inject water into the blasting hole to form a water-coupled section. Utilizing the characteristic that the shock wave generated by the explosives decays slowly in water, the blasting cost is reduced, charging construction is simpler, production efficiency is improved, and there is good economic benefit. It has a wide range of promotion and application value for projects using pre-splitting blasting.

[0015] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Schematic diagram of the structure of the water-coupled pre-splitting blasting charge used in the embodiment.

[0017] Figure 2 Schematic diagram of the process of blasting using a water-coupled pre-splitting blasting charge structure according to an embodiment.

[0018] Numbers in the figure: 1-mixed explosive, 2-water coupling section, 3-blasting mud, 4-detonating detonator, 5-detonator leg line. DETAILED DESCRIPTION Example

[0019] The technical solutions in this embodiment are described clearly and completely below with reference to the accompanying drawings. It is obvious that the described embodiments are only a portion of the embodiments of the present invention, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort are also within the scope of protection of the present invention.

[0020] See also Figure 1 The diagram shows a specific embodiment of a water-coupled pre-splitting blasting charge structure according to the present invention. From the inside out, the blasthole comprises a charging section, a water-coupling section, and a packing section. Mixed explosives 1 are placed at the bottom of the blasthole, close to the blasthole wall, forming the charging section. Detonating caps 4 are embedded in the charging section to detonate the mixed explosives. Detonator legs 5 of the detonating caps 4 extend out of the blasthole and connect to the detonation network. Water is injected into the blasthole above the charging section to form a water-coupling section 2. The top of the water-coupling section 2 is filled with taphole mud 3 to seal the blasthole opening, forming the packing section. The impact energy generated by the detonation of the charging section is stably attenuated in the water-coupling section, promoting the formation of pre-cracks along the rock mass and absorbing excess energy to prevent excessive damage to other rock masses.

[0021] In this embodiment, the water coupling section 2 is formed by enclosing the charge section at the bottom of the blasthole and the blasthole wall. Water is directly injected into the blasthole to form the water coupling section 2. Because the injected water directly contacts the charge below, the mixed explosive 1 is mixed with a hydrophobic emulsifier and sensitizer and the explosive matrix. After the mixed explosive 1 is formed at the bottom of the blasthole, it adheres tightly to the blasthole wall, preventing the mixed explosive 1 from being dispersed and diluted during water injection. To prevent the mixed explosive 1 and water from being washed out of the blasthole by the explosion shock wave and affecting the blasting effect, the blasthole mouth is strictly filled with clay mud to form a filling section. The clay mud filling section is located above the water coupling section 2 and is not completely soaked by the water coupling section, thus maintaining its integrity and sealing the blasthole.

[0022] The blasting detonator 4 of this embodiment uses an electronic detonator as an active detonating component. In actual applications, other types of detonators can also be used according to the detonating performance of the actual explosives used.

[0023] The length of the charging section in this embodiment depends on the rock properties, blasthole diameter, blasthole spacing, energy leakage rate, and the stable impact energy of the explosive in the blasthole. Generally, the length of the charging section formed by the mixed explosive 1 is 20-25% of the blasthole length, the length of the water coupling section 2 is 63-71% of the blasthole length, and the length of the remaining filling section is 9-12% of the blasthole length.

[0024] like Figure 2 As shown, the blasting method using the water-coupled pre-splitting blasting charge structure of this embodiment specifically includes the following steps: S1. Use a drilling rig to drill blast holes in the pre-splitting blasting area. Clean the impurities in the blast holes before charging, and use high-pressure air to blow out impurities such as gravel in the holes.

[0025] S2. Place the detonating cap as the active detonating component at the bottom of the blasting hole. Lead the detonator leg wire connected to the detonating cap out of the blasting hole. Use a mixing truck to fill the mixed explosives to the bottom of the blasting hole to form a charging section. During the charging process, pay attention to the normal laying of the detonator leg wire leading out of the charging section to avoid excessive pulling on the detonator leg wire, which may cause the detonator leg wire and the detonating cap to loosen.

[0026] S3. After the charging section is formed, water is injected into the blasting hole on the charging section to form a water coupling section, and the blasting hole is sealed by filling mud from the top of the water coupling section to the hole mouth.

[0027] S4. Complete the charging of all blasting holes in the pre-splitting blasting area according to steps S2 and S3, and connect the detonator legs from all blasting holes to the initiation network for initiation.

[0028] The following embodiment is specifically applied to the 1000 mL middle section - N2MU-3# downward parallel hole stope of the southeast ore body of China Nonferrous Metals Africa Mining Co., Ltd. to perform pre-splitting blasting for the stope.

[0029] Using this embodiment Figure 1 The charging structure in the blasting process is as follows: (1) The design uses a T100 down-the-hole drill to drill blast holes. The construction hole length is 16m and the hole diameter is 76mm. A high-pressure blower is used to blow out impurities such as gravel in the hole.

[0030] (2) A mixed explosives truck is used to load mixed explosives into the bottom of the blasthole. The charge length is 3.5 m. The electronic detonator is used as an active detonating component and is placed at the bottom of the blasthole to form a charge section.

[0031] (3) Water is injected into the blasting hole on the charging section, and the height of the water coupling section formed is 11m.

[0032] (4) Use gun mud to fill the hole mouth, and the length of the filling section is 1.5m.

[0033] The above-mentioned pre-splitting blasting charging structure reduces the charging cost compared with the traditional continuous charging, and the charging construction efficiency is faster. The pre-cracks formed by the pre-splitting blasting are basically distributed along the designed contour line, and the rock mass retained outside the pre-cracks is basically not damaged by the blasting.

[0034] The above embodiments are merely examples to clearly illustrate the present invention and are not intended to limit its implementation. Those skilled in the art will readily appreciate that other variations or modifications based on the above descriptions are possible. It is not necessary and impossible to provide an exhaustive list of all embodiments. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A water-coupled pre-splitting blasting charge structure, characterized by: The bottom of the blasting hole is filled with mixed explosives (1) close to the hole wall to form a charging section, and a detonating cap (4) is pre-buried in the charging section. The detonator leg line of the detonating cap (4) is led out of the hole. A water coupling section is provided on the blasting hole on the charging section, and the top of the water coupling section to the hole mouth is filled with gun mud to seal it.

2. A water-coupled pre-splitting blasting charge structure according to claim 1, characterized in that: The mixed explosive (1) is prepared by mixing a hydrophobic oil phase material with the explosive.

3. The water-coupled pre-splitting blasting charge structure according to claim 1, characterized in that: The water coupling section is surrounded by the charge section at the bottom of the blasthole and the blasthole wall to form a container, and water is directly injected into the blasthole to form the water coupling section.

4. The water-coupled pre-splitting blasting charge structure according to claim 1, characterized in that: The detonator is an electronic detonator.

5. The water-coupled pre-splitting blasting charge structure according to claim 1, characterized in that: The length of the filling section is 9-12% of the length of the blasting hole, the length of the water coupling section is 63-71% of the length of the blasting hole, and the length of the charging section is 20-25% of the length of the blasting hole.

6. A blasting method using the water-coupled pre-splitting blasting charge structure according to any one of claims 1 to 5, characterized in that The steps include: S1. Use a drilling rig to drill blast holes in the pre-splitting blasting area and clean impurities in the blast holes before charging; S2. Placing a blasting cap as an active detonating component at the bottom of the blasting hole, leading the detonator leg wire connected to the blasting cap out of the blasting hole, and using a mixing truck to fill the mixed explosives to the bottom of the blasting hole to form a charging section; S3, injecting water into the blasting hole on the charging section to form a water coupling section, and filling the blasting hole with mud from the top of the water coupling section to the blasting hole mouth to seal the blasting hole; S4. Complete the charging of all blasting holes in the pre-splitting blasting area according to steps S2 and S3, and connect the detonator legs from all blasting holes to the initiation network for initiation.

Images