Preparation and application method of open bench blasting water medium interval charging structure

Abstract

The invention discloses a preparation and application method of an open bench blasting water medium interval charging structure, the open bench blasting water medium interval charging structure comprises a blast hole, an explosive, a water medium and a filling material, the water medium is arranged in the blast hole at intervals, the explosive is divided into an upper section and a lower section by the water medium, the interval length between the middle and the bottom of the blast hole is 8%-13% of continuous charging, and the filling material is filled in the blast hole. The total interval length of the blast holes is 15%-25% of continuous charging; and the top of the blast hole is filled with the filling material. According to the method, multiple factors in the blasting process are comprehensively considered, by optimizing the charging structure and the application method, the blasting quality and efficiency are improved, the blasting harmful effect is reduced, and remarkable economic and environmental benefits are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of open-pit step blasting, and in particular to a preparation and application method of a water medium spaced charge structure for open-pit step blasting. Background Art

[0002] Blasting is a crucial construction method in open-pit mining, transportation engineering, and other fields. Currently, the commonly used air-interval charge blasting system presents numerous challenges. In operations such as stripping in open-pit coal mining areas, conventional air-interval charge blasting can lead to undesirable effects such as insufficient step pile settlement, excessive large blocks, and a high number of root deposits, due to factors such as the development of rock joints and fissures and differences in rock strata properties. This not only increases secondary blasting costs, but also impacts construction progress and can even cause safety accidents.

[0003] With the advancement of engineering technology, the demand for blasting effectiveness is increasing, necessitating a more efficient, environmentally friendly, and economical charge structure and application method. As a new blasting method, water-based intermittent charge structures have demonstrated certain advantages in tunneling blasting, but their application in open-pit bench blasting requires further research and optimization. Therefore, developing a method for preparing and applying a water-based intermittent charge structure suitable for open-pit bench blasting is of great practical significance. To this end, we propose a method for preparing and applying a water-based intermittent charge structure for open-pit bench blasting. Summary of the Invention

[0004] The purpose of the present invention is to solve the shortcomings of the prior art and to propose a preparation and application method of a water medium interval charging structure for open-air step blasting.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions: A water medium interval charging structure for open-air step blasting includes a blasthole, explosives, a water medium and a filling material. The water medium is arranged in the blasthole, and the water medium divides the explosives into two sections, the upper and lower sections. The length of the interval between the middle and the bottom of the blasthole is 8%-13% of the continuous charging, and the total interval length of the blasthole is 15%-25% of the continuous charging; the filling material is filled at the top of the blasthole.

[0006] Preferably, the blasthole is in the form of a vertical drilling, and the diameter of the blasthole is in the range of 150-200 mm.

[0007] Preferably, the explosive is 2# rock emulsion explosive as the detonating charge, mixed explosive is used as the main explosive, and the filling material is rock debris.

[0008] Preferably, the length of the water medium bag is 0.6 m, the diameter of the water medium bag is smaller than the diameter of the blast hole, and the water medium bag is filled with 85% water and the air in the bag is exhausted before being sealed.

[0009] A preparation and application method of a water medium spaced charge structure for open-pit step blasting comprises the following steps: S1. Preparation of water bag for water medium: select a water bag with a length of 0.6m and a diameter smaller than the diameter of the blasthole, fill it with about 85% water, then expel the air in the bag and seal it with a sealing machine; S2. Charge structure loading: First, slowly place the empty water bag into the blasthole, then place the water bag containing water medium 2, and then load the explosives to complete the charging of the lower water spacer and the lower charge column; repeat the above steps to complete the charging of the upper water spacer and the upper charge column; finally, add the filling material to complete the charging of the entire blasthole; S3. Blasting plan design: Determine the blasthole diameter, hole depth, over-depth, chassis resistance line, blasthole spacing, row spacing, filling length, unit explosive consumption, interval length, and single-hole charge based on the height of the open-pit bench, rock properties, and on-site construction equipment; S4. Blasting Implementation: Carry out operations such as hole placement, charge loading, and wiring according to the designed blasting plan, adopt a micro-difference hole-by-hole blasting method, and use industrial electronic detonators to control the detonation sequence and delay time; S5. Blasting vibration monitoring: TC-4850 blasting vibration meter is placed at a certain distance from the blasting area to monitor the blasting vibration signal, including the vibration velocity, frequency and duration of the rock mass particles. The results are compared and verified with national standards, and blasting parameters are adjusted in real time based on the monitoring results. S6. Evaluation of blasting effect: After blasting, Split-Desktop software is used to analyze the size of the blasted pile, calculate the proportion of rock blocks in different size ranges, and evaluate the uniformity and rationality of the blasted size; by observing the bottom surface of the steps, it is determined whether a foundation has been formed; MATLAB software is used to process dust images, analyze dust concentration, and evaluate the dust reduction effect.

[0010] Preferably, in step S3, the unit explosive consumption ranges from 0.33 to 0.34 kg / m³.

[0011] Preferably, in step S4, the delay time between holes ranges from 15 to 30 ms, and the delay time between rows ranges from 40 to 70 ms.

[0012] Preferably, in step S5, the monitoring point is arranged at a location 30-50 m away from the explosion area.

[0013] Preferably, in step S6, the blasting effect is judged by comparing the proportions of rock blocks in different size ranges, wherein the proportion of rock blocks with a size less than 10 cm should be less than 20%, the proportion of rock blocks with a size between 10-70 cm should be greater than 70%, and the proportion of rock blocks with a size greater than 70 cm should be less than 10%.

[0014] Compared with the prior art, the present invention has the following beneficial effects: The water-interval charge structure in this invention effectively improves the energy transfer efficiency of explosives, causing the blast wave to decay more slowly in water, concentrating the energy on the rock mass and enhancing the blasting and fragmentation effect. Compared with air-interval charge structures, this structure reduces explosive consumption per unit while achieving the same blasting effect, saving costs. Field tests have determined the optimal explosive consumption per unit to be 0.33-0.34 kg / m³, saving 0.03-0.04 kg / m³ compared to previous methods.

[0015] The water-based intermittent charge structure in this invention also has a good dust reduction effect. The water is transformed into fine droplets by the blast shock wave, which can capture and collect dust, reducing dust pollution in the air. In terms of blast vibration control, the impact of blast vibration on the surrounding environment and buildings can be effectively reduced by properly designing the delay time and monitoring the vibration signal.

[0016] The present invention comprehensively considers multiple factors in the blasting process, improves blasting quality and efficiency, reduces harmful effects of blasting, and has significant economic and environmental benefits by optimizing the charge structure and application method. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic structural diagram of a water medium interval charging structure for open-air step blasting proposed by the present invention; In the figure: 1 blasthole; 2 explosive; 3 water medium; 4 filling material. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0019] Reference Figure 1 A water medium interval charging structure for open-air step blasting includes a blasthole 1, explosives 3, water medium 2 and filling material 4. The water medium 2 is arranged in the blasthole 1, and the water medium 2 divides the explosives 3 into two sections, the upper and lower sections. The interval length between the middle and bottom of the blasthole 1 is 8%-13% of the continuous charging, and the total interval length of the blasthole 1 is 15%-25% of the continuous charging; the filling material 4 is filled at the top of the blasthole 1.

[0020] The blast hole 1 is drilled vertically, and the diameter of the blast hole 1 ranges from 150 to 200 mm.

[0021] Explosive 3 uses 2# rock emulsion explosive as the detonating charge, mixed explosive as the main explosive, and filling material 4 uses rock debris.

[0022] The length of the water bag of water medium 2 is 0.6m, the diameter of the water bag of water medium 2 is smaller than the diameter of the blasthole 1, and the water bag of water medium 2 is filled with 85% water and the air in the water bag is discharged and then sealed.

[0023] A preparation and application method of a water medium spaced charge structure for open-pit step blasting comprises the following steps: Preparation of water bag for S1 and water medium 2: select a water bag with a length of 0.6m and a diameter smaller than the diameter of blasthole 1, fill it with about 85% water, then expel the air in the bag and seal it with a sealing machine; S2. Charge structure loading: First, slowly place the empty water bag into the blasthole 1, then place the water bag containing the water medium 2, and then load the explosive 3 to complete the charging of the lower water spacer and the lower charge column; repeat the above steps to complete the charging of the upper water spacer and the upper charge column; finally, load the filling material 4 to complete the charging of the entire blasthole 1; S3. Blasting plan design: Determine the blasthole 1 diameter, hole depth, over-depth, chassis resistance line, spacing, row spacing, filling length, unit explosive consumption, interval length, and single-hole charge based on the height of the open-pit bench, rock properties, and on-site construction equipment; S4. Blasting Implementation: Carry out operations such as hole placement, charge loading, and wiring according to the designed blasting plan, adopt a micro-difference hole-by-hole blasting method, and use industrial electronic detonators to control the detonation sequence and delay time; S5. Blasting vibration monitoring: TC-4850 blasting vibration meter is placed at a certain distance from the blasting area to monitor the blasting vibration signal, including the vibration velocity, frequency and duration of the rock mass particles. The results are compared and verified with national standards, and blasting parameters are adjusted in real time based on the monitoring results. S6. Evaluation of blasting effect: After blasting, Split-Desktop software is used to analyze the size of the blasted pile, calculate the proportion of rock blocks in different size ranges, and evaluate the uniformity and rationality of the blasted size; by observing the bottom surface of the steps, it is determined whether a foundation has been formed; MATLAB software is used to process dust images, analyze dust concentration, and evaluate the dust reduction effect.

[0024] In step S3, the unit explosive consumption ranges from 0.33 to 0.34 kg / m³.

[0025] In step S4, the delay time between holes ranges from 15 to 30 ms, and the delay time between rows ranges from 40 to 70 ms.

[0026] In step S5, the monitoring point is arranged at a location 30-50m away from the explosion area.

[0027] In step S6, the blasting effect is judged by comparing the proportions of rock blocks in different size ranges. The proportion of rock blocks with a size less than 10 cm should be less than 20%, the proportion of rock blocks with a size between 10-70 cm should be greater than 70%, and the proportion of rock blocks with a size greater than 70 cm should be less than 10%.

[0028] Working principle: Preparation of charging structure: According to the design requirements, a water bag with a length of 0.5m and a water medium 2 is made. A water bag with a length of 0.6m and a diameter of 160mm (slightly smaller than the diameter of the blasthole 170mm) is selected. It is filled with about 85% water, and the air in the bag is discharged and sealed with a sealing machine; during the charging process, follow the following steps: first slowly place the 170mm empty water bag into the blasthole, then slowly place the water bag with water medium 2, and then load the explosive 3 to complete the charging of the lower water interval and the lower charge column; repeat the above operations to complete the charging of the upper water interval and the upper charge column; finally, load the filling material 4 to complete the charging of the entire blasthole 1.

[0029] Application method implementation: Blasting plan design: The step height is determined to be 12m based on the rock layer height; the blasthole diameter is 170mm; 2# rock emulsion explosive is used as the detonator, and mixed explosive is used as the main explosive; the detonator type is industrial electronic detonator; the drilling method is vertical drilling; the hole depth is 13m (1m overdeep); the chassis resistance line is calculated according to the formula WD=(20-38)D1, and the actual value is 3.5m; the blasthole spacing is 7.0m, the row spacing is 5.0m, and the hole layout is triangular; the filling length is 3.5m; the unit explosive consumption is 0.34kg / m³; the interval length is 1m for the water medium in the middle of the blasthole and 1m for the water medium at the bottom of the hole; the single hole charge is calculated according to the formula Q=qabH and is 145kg.

[0030] Blasting implementation: Hole arrangement, charge loading, wiring and other operations are carried out according to the designed blasting plan. A micro-difference hole-by-hole blasting method is adopted, with a delay of 17ms between holes and 42ms between rows. Industrial electronic detonators are used to control the detonation sequence.

[0031] Blasting vibration monitoring: Three TC-4850 blasting vibration meters were installed on the upper platform 30 meters from the comparative test blasting area. The instrument measurement points were numbered #1, #2, and #3, with a distance of 15 meters between adjacent vibration meters. The vibration velocity, frequency, and duration of rock mass points were monitored. The monitoring results were compared and verified with national standards, and blasting parameters were adjusted in real time based on the monitoring results.

[0032] Blasting effect evaluation: After blasting, Split-Desktop software was used to analyze the blast pile fragmentation. Two typical high-definition fragmentation photos from water- and air-interval charge blasting were selected for processing and analysis. The results showed that the powder fragmentation rate, utilization rate, and large fragmentation rate of water-interval charge blasting were 15.54%, 79.23%, and 5.23%, respectively. Compared with air-interval charge blasting, the large fragmentation rate and powder fragmentation rate decreased by 8.12%, 2.66%, and the utilization rate increased by 10.78%. By observing the bottom surface of the steps, it was found that the bottom surface of the steps blasted with water-interval charge blasting was smooth and no foundation was generated. Dust images were processed using MATLAB software, and analysis showed that the dust concentration generated by water-interval charge blasting was lower than that of air-interval charge blasting, indicating that water-interval charge blasting had a good dust reduction effect.

[0033] The water-medium interval charging structure can effectively improve the energy transfer efficiency of explosives, making the explosion shock wave decay more slowly in water, and the energy is more concentrated on the rock mass, thereby improving the blasting and crushing effect. Compared with the air-medium interval charging structure, when achieving the same blasting effect, the unit consumption of explosives can be reduced, saving costs; the optimal unit consumption of explosives determined through field tests is 0.33-0.34kg / m³, which saves 0.03-0.04kg / m³ of explosives compared to the previous unit consumption; the water-medium interval charging structure also has a good dust reduction effect. Water is transformed into fine water droplets by the explosion shock wave, which can capture and collect dust, reducing dust pollution to the air. In terms of blasting vibration control, the impact of blasting vibration on the surrounding environment and buildings can be effectively reduced by reasonably designing the delay time and monitoring the vibration signal; taking into account multiple factors in the blasting process, by optimizing the charging structure and application method, the blasting quality and efficiency are improved, the harmful effects of blasting are reduced, and it has significant economic and environmental benefits. The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A water medium interval charging structure for open-air step blasting, comprising a blasthole (1), explosives (3), a water medium (2) and a filling material (4), characterized in that: The water medium (2) is arranged at intervals in the blasthole, and the water medium (2) divides the explosive (3) into two sections, the upper and lower sections. The interval length between the middle and the bottom of the blasthole (1) is 8%-13% of the continuous charge, and the total interval length of the blasthole (1) is 15%-25% of the continuous charge; the filling material (4) is filled at the top of the blasthole (1).

2. The water medium interval charging structure for open-air step blasting according to claim 1 is characterized in that: The blasthole (1) is in the form of a vertical drilling, and the diameter of the blasthole (1) ranges from 150 to 200 mm.

3. The water medium interval charging structure for open-air step blasting according to claim 1 is characterized in that: The explosive (3) uses 2# rock emulsion explosive as the detonating charge, and the mixed explosive is used as the main explosive. The filling material (4) uses rock debris.

4. The water medium interval charging structure for open-air step blasting according to claim 1 is characterized in that: The length of the water bag of the water medium (2) is 0.6 m, the diameter of the water bag of the water medium (2) is smaller than the diameter of the blast hole (1), and the water bag of the water medium (2) is filled with 85% water and the air in the water bag is exhausted before being sealed.

5. An application method of the open-pit step blasting water medium interval charging structure according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1. Preparation of water bag for water medium (2): Select a water bag with a length of 0.6m and a diameter smaller than the diameter of the blasthole (1), fill it with about 85% water, then remove the air from the bag and seal it with a sealing machine; S2. Charge structure filling: first, slowly place the empty water bag into the blasthole (1), then place the water bag with water medium (2), and then fill the explosives to complete the charging of the lower water spacer and the lower powder column; repeat the above operation to complete the charging of the upper water spacer and the upper powder column; finally, fill the filling material (4) to complete the charging of the entire blasthole (1); S3. Blasting plan design: Determine the blasthole (1) diameter, hole depth, over-depth, chassis resistance line, blasthole spacing, row spacing, filling length, unit explosive consumption, interval length, and single-hole charge based on the height of the open-pit step, rock properties, and on-site construction equipment; S4. Blasting Implementation: Carry out operations such as hole placement, charge loading, and wiring according to the designed blasting plan, adopt a micro-difference hole-by-hole blasting method, and use industrial electronic detonators to control the detonation sequence and delay time; S5. Blasting vibration monitoring: TC-4850 blasting vibration meter is placed at a certain distance from the blasting area to monitor the blasting vibration signal, including the vibration velocity, frequency and duration of the rock mass particles. The results are compared and verified with national standards, and blasting parameters are adjusted in real time based on the monitoring results. S6. Evaluation of blasting effect: After blasting, Split-Desktop software is used to analyze the size of the blasted pile, calculate the proportion of rock blocks in different size ranges, and evaluate the uniformity and rationality of the blasted size; by observing the bottom surface of the steps, it is determined whether a foundation has been formed; MATLAB software is used to process dust images, analyze dust concentration, and evaluate the dust reduction effect.

6. The method for preparing and applying a water medium spaced charge structure for open-pit step blasting according to claim 1, characterized in that: In step S3, the unit explosive consumption ranges from 0.33 to 0.34 kg / m³.

7. The method for preparing and applying a water medium spaced charge structure for open-pit step blasting according to claim 1 is characterized in that: In step S4, the delay time between holes ranges from 15 to 30 ms, and the delay time between rows ranges from 40 to 70 ms.

8. The method for preparing and applying a water medium spaced charge structure for open-pit step blasting according to claim 1 is characterized in that: In step S5, the monitoring point is arranged at a location 30-50 m away from the explosion area.

9. The method for preparing and applying a water medium spaced charge structure for open-pit step blasting according to claim 1, characterized in that: In step S6, the blasting effect is judged by comparing the proportions of rock blocks in different size ranges, wherein the proportion of rock blocks with a size less than 10 cm should be less than 20%, the proportion of rock blocks with a size between 10-70 cm should be greater than 70%, and the proportion of rock blocks with a size greater than 70 cm should be less than 10%.

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