Electronic detonator based hole-by-hole initiation network setting method

Abstract

This invention relates to the field of engineering blasting technology and discloses a method for setting up a hole-by-hole initiation network based on electronic detonators. The method includes: acquiring basic parameters of the blasting area; calculating the maximum time difference for the completion of explosive detonation within the borehole; calculating the time required for stress waves to propagate in the rock mass at a predetermined multiple of the isochronous hole spacing as the stress wave propagation time; determining a reference delay time based on the sum of the maximum time difference and the stress wave propagation time; determining the inter-hole delay time based on the total number of rows in the blasting area and the reference delay time; and determining the inter-row delay time based on the free surface morphology of the blasting area and the preset initiation network morphology. This invention introduces physical and mechanical parameters such as rock mass wave velocity and explosive detonation velocity to establish a scientific delay time calculation model. This ensures that the stress wave peaks of adjacent boreholes on the isochronous lines are staggered, avoiding vibration superposition. This effectively controls blasting vibration while improving blasting efficiency, fully leveraging the technical advantage of arbitrarily settable delay times with electronic detonators.

Description

Technical Field

[0001] This invention belongs to the field of engineering blasting technology, and in particular relates to a method for setting up a hole-by-hole initiation network based on electronic detonators. Background Technology

[0002] Since its widespread adoption in my country in 2019, electronic detonators have provided a new technical means to improve blasting effects and control blasting vibrations due to their advantages such as high delay accuracy and the ability to arbitrarily set delay times. However, in practical applications, the delay time settings of electronic detonator initiation networks mostly still refer to traditional detonating cord detonator networks, or are simply modified from them, failing to fully leverage the technical advantages of electronic detonators.

[0003] The existing deep-hole stepped blasting network design methods mainly include the following:

[0004] 1. The millisecond delay interval is determined by the time required for the formation of a new free surface. According to extensive statistical data, the time from detonation to rock fracturing and displacement is approximately 5 to 10 times the time required for the stress wave to reach the free surface; that is, the time for rock fracturing and displacement is directly proportional to the minimum resistance line. In the formula The delay interval is in milliseconds (ms). It is a coefficient related to rock properties, structure and blasting conditions (usually taken as 2 to 5 under open-pit bench blasting conditions). The minimum resistance line or chassis resistance line (m).

[0005] 2. Empirical formula considering rock properties and chassis resistance line: In the formula The delay interval is in milliseconds (ms). The rock fracture coefficient is 0.5 (0.75 for rocks with few fractures, 0.75 for rocks with moderate fractures, and 0.9 for rocks with well-developed fractures). The chassis resistance line (m). This represents the rock firmness coefficient.

[0006] 3. The empirical formula proposed by Changsha Mining Research Institute: In the formula The rock strength coefficient, The chassis resistance line (m).

[0007] 4. Orica's sequential detonation delay scheme: inter-hole delay = 3~8ms / m × hole spacing, inter-row delay = 15~30ms / m × row spacing.

[0008] The aforementioned existing technologies have the following shortcomings: First, the selection of delay time is mostly based on experience, lacking a systematic consideration of the propagation law of explosive stress waves and the physical and mechanical parameters of rock mass; second, regardless of the size of the blasting zone, the same delay scheme is often selected, failing to differentiate designs based on the number of rows in the blasting zone, free surface conditions, etc.; third, there are often overlapping delay settings between holes and between rows, resulting in a significant superposition effect of blasting vibration; and fourth, the characteristic that the delay time of electronic detonators can be arbitrarily set is not fully utilized to give full play to their potential in accurately controlling the blasting and fracturing process and reducing vibration. Summary of the Invention

[0009] The purpose of this invention is to provide a method for setting up a hole-by-hole detonation network based on electronic detonators, in order to solve the above-mentioned problems.

[0010] This invention is implemented as follows: a method for setting up a hole-by-hole initiation network based on electronic detonators, comprising the following steps: Step 1: Obtaining basic parameters of the blasting area, wherein the basic parameters include at least: the length of the charge inside the borehole. Explosive detonation velocity Rock mass wave velocity And the hole spacing between adjacent boreholes on the detonation isochrone. Step 2: Calculate the maximum time difference for the completion of explosive detonation inside the borehole. Step 3: Calculate the stress wave propagation time The The stress wave propagation in the rock mass is 3 to 5 times the hole spacing. The time required to travel the distance, i.e. Step 4: Determine the baseline delay time The Maximum time difference With the stress wave propagation time The sum of Step 5: Based on the total number of rows in the explosion zone Determine the inter-hole delay time , Step 6: Determine the delay time between rows based on the free surface morphology of the blast zone and the preset detonation network morphology. .

[0011] In a further technical solution, step 2 involves calculating the maximum time difference between the completion of explosive detonation within the borehole. The method is as follows: determine the completion time of single-hole detonation based on the initiation method. The range, then For single-point detonation, For two-point detonation, .

[0012] In a further technical solution, in step 5, the inter-hole delay time The value is no greater than 60ms.

[0013] In a further technical solution, in step 6, the blast zone free surface morphology includes a first blast zone morphology with side free surfaces, and a second blast zone morphology without side free surfaces and only having front row free surfaces.

[0014] A further technical solution, when the detonation network configuration is the first configuration: for the first detonation zone configuration with side free surfaces, the inter-row delay time... For the second type of burst zone without a side free surface, the inter-row delay time... .

[0015] A further technical solution, when the detonation network configuration is the second configuration: for the first detonation zone configuration with side free surfaces, the inter-row delay time... For the second type of burst zone without a side free surface, the inter-row delay time... .

[0016] A further technical solution is that the detonation network configuration is either a first configuration with a moderate distribution of downward and rightward components in the thrust direction, or a second configuration where the downward component in the thrust direction is greater than the rightward component.

[0017] In a further technical solution, the basic parameters also include borehole spacing. The hole spacing between adjacent boreholes on the detonation isochrone. Based on the arrangement of boreholes and the borehole spacing and row spacing Calculated.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0019] 1. Effectively control blasting vibration and reduce harm to nearby buildings and structures. This invention introduces the rock mass wave velocity V as a key parameter and uses the stress wave propagation time of 3 to 5 times the isochronous hole spacing as a time reference to ensure that the stress wave peaks of adjacent blast holes on the isochronous line are staggered, avoiding vibration superposition and achieving the vibration reduction target from a mechanistic perspective.

[0020] 2. Effectively reduces the density of the blast pile and improves excavation and transportation efficiency. This invention maintains good looseness and concentration of the blast pile by scientifically setting the delay time between holes and between rows, which facilitates mechanical loading operations.

[0021] 3. Effectively reduces the proportion of large pieces and improves crushing quality. This invention fully utilizes the interaction of explosive stress waves, subjecting the rock mass to tensile and shearing forces in multiple directions, resulting in more uniform crushing and a significant reduction in the proportion of large pieces, thereby reducing subsequent crushing energy consumption and blasting costs.

[0022] 4. Improve the concentration of blast piles. This invention optimizes the delay scheme based on different blast zone and detonation network configurations to maintain a reasonable throwing distance and concentration of blast piles, avoiding excessive dispersion of blast piles that could affect loading efficiency.

[0023] 5. Fully leverage the technological advantages of electronic detonators. This invention breaks through the limitations of traditional empirical formulas and establishes a scientific calculation model based on rock mass physical and mechanical parameters and blasting zone geometry. This fully utilizes the characteristic of arbitrarily setting the delay time of electronic detonators, achieving optimization of blasting effect and vibration control. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the first type of detonation network of the present invention;

[0025] Figure 2 This is a schematic diagram of the second type of detonation network of the present invention;

[0026] Figure 3 This is a schematic diagram of the third type of detonation network of the present invention;

[0027] Figure 4 This is a schematic diagram of the fourth type of detonation network of the present invention;

[0028] Figure 5 This is a schematic diagram of the blast zone morphology with a free side surface according to the present invention;

[0029] Figure 6 This is a schematic diagram of the explosion zone morphology of the present invention, which has no side free surfaces and only front free surfaces. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0031] This invention is mainly based on the following technical ideas:

[0032] 1. Fully utilize the interaction of explosive stress waves. Taking the wave velocity of the blasted rock mass as the main consideration, by reasonably setting the delay time, the stress waves generated by the explosions of adjacent boreholes interact within the rock mass, thereby enhancing the fragmentation effect.

[0033] 2. Fully leverage the advantages of sequential detonation. The detonation delay time between adjacent boreholes on the isochronous line is short, allowing for full interaction of the explosive stress waves. Within the same row, the delay time between adjacent boreholes satisfies the principle that the first borehole creates a new free surface for the subsequent boreholes. By leveraging the advantages of the sequential detonation network, the energy of the explosive stress waves is fully utilized, improving blasting effectiveness and reducing explosive consumption.

[0034] 3. By using a reasonable network configuration scheme, the blast zone can have a stable ignition surface, and the direction of the isochrones can be precisely controlled to reduce the delay time on the isochrones, thereby obtaining greater thrust and reducing the resistance of the after-blast hole.

[0035] 4. Give full play to the advantages of large hole spacing and small row spacing initiation network in terms of crushing capacity.

[0036] 5. Avoid repeated sections as much as possible to reduce blasting vibration.

[0037] The specific implementation of the present invention will be described in detail below with reference to specific embodiments.

[0038] To facilitate the description of the technical solution of this invention, the following basic parameters are first defined:

[0039] Length of charge —The actual length of the explosive charge inside the borehole, in meters;

[0040] Explosive detonation velocity —The detonation velocity of the explosive used, in m / s;

[0041] Number of rows of gun holes —The total number of rows in the blasting zone is a positive integer;

[0042] Rock mass wave velocity —P-wave velocity of the blasted rock mass, in m / s;

[0043] Detonation isochrone – the line connecting adjacent boreholes with the smallest detonation time difference.

[0044] Ignition Network Pattern

[0045] Based on the principle of setting up a hole-by-hole detonation network, four types of detonation network configurations can be formed by setting different inter-hole delay times and inter-row delay times.

[0046] like Figure 1 As shown, the first type of detonation network is a preferred detonation network: the thrust direction is downward and the right component is moderately distributed, which can achieve good blasting effect when facing a network with a large number of rows, and the blast pile is loose and relatively concentrated; the front row of blast holes can form a good free surface for the rear row of blast holes; the spacing between blast holes on the isochron is moderate, which can make full use of the interaction of the explosion stress waves, improve the rock fragmentation, and reduce the amount of explosives consumed.

[0047] like Figure 2 As shown, the second type of detonation network is a suboptimal detonation network: the downward component of the thrust is larger and the rightward component is smaller, the concentration of the blast pile is poor but the looseness is good; when facing a blast zone with a large number of rows, the rear row is prone to slag compression, which leads to the deterioration of the blasting effect; the spacing between the blast holes on the isochronous line is too large, which cannot make full use of the interaction of the explosion stress waves.

[0048] like Figure 3 As shown, the third type of detonation network is a relatively poor detonation network: the downward component of the thrust is too large and the rightward component is too small, resulting in poor concentration of the explosive pile; the spacing between the blast holes on the isochronous line is too large, and the interaction of the explosive stress waves cannot be utilized at all.

[0049] like Figure 4 As shown, the fourth type of detonation network is the worst type of detonation network: the front row of blast holes cannot form a good free surface for the rear row of blast holes, and cannot give full play to the advantages of the sequential detonation network; the thrust direction is biased to the right, and it tends to slag-pressing blasting for long blasting areas, resulting in increased unit consumption and insufficient looseness of the blast pile.

[0050] In order to fully leverage the advantages of the hole-by-hole detonation network, the first and second forms are preferred as research objects in this invention.

[0051] Time required for explosive detonation to complete

[0052] The time required for explosives to complete detonation inside a blast hole depends on the detonation method. This invention focuses on single-point and two-point detonation methods commonly used in open-pit bench mining.

[0053] In a single-point detonation, the detonation propagates from the detonation point to the other end, and the detonation completion time is... for:

[0054]

[0055] In a two-point detonation, one detonating charge is typically placed in the lower part of the borehole, and the other in the upper part. The blast wave propagates simultaneously from both detonation points in opposite directions. The detonation completion time... for:

[0056]

[0057] Stress wave propagation time

[0058] The shock wave attenuates into a stress wave within a distance of 3 to 7 times the borehole radius, and its propagation time is negligible. This invention uses the distance between adjacent boreholes on the detonation isochrone. Using distance as a reference, calculate the time required for stress wave propagation.

[0059] Based on the actual monitoring results of blasting vibration, when the stress wave propagation radius is (2~3) When adjacent boreholes on the isochrone complete detonation, it can play a certain role in vibration reduction; when the stress wave propagation radius is (3~5) When the stress wave propagation radius is greater than 5, a relatively ideal vibration reduction effect can be achieved; At that time, the improvement in vibration reduction effect was limited.

[0060] To maximize the blasting effect while minimizing blasting vibration, this invention uses a stress wave propagation radius of (3~5). Calculate stress wave propagation time :

[0061]

[0062] Determination of the baseline extension period

[0063] During the loading process, the position of the detonating charge deviates from the design to a certain extent. To ensure that the stress wave peaks are staggered (3~5), The distance needs to be Add a time difference for the completion of detonation to the existing data. For any detonation method, The maximum value is equal to ,Right now:

[0064]

[0065] The time difference between the detonation of adjacent blast holes on the isochrone is called the reference delay time. Then we have:

[0066]

[0067] Determination of inter-hole delay

[0068] Let the number of rows in the blast zone be . Inter-hole delay time The following is confirmed:

[0069] when When ≤5,

[0070] when >5 o'clock,

[0071] At the same time, in order to achieve good blasting results, The recommended value is no greater than 60ms; when the requirements for blasting vibration control are high, the value can be selected according to the actual calculated value.

[0072] Determination of row room extension

[0073] Based on the free surface conditions of the blast zone, this invention distinguishes two blast zone morphologies:

[0074] The first type of explosion zone: When the working face is in normal production, the explosion zone has free sides, such as... Figure 5 As shown.

[0075] The second type of blast zone: When the working face is opened, the blast zone has no side free surfaces, only front free surfaces, such as... Figure 6 As shown.

[0076] For different detonation network and detonation zone configurations, the inter-row delay time... The calculation formula is as follows:

[0077] For the first type of explosion zone (with a free side surface):

[0078] First-stage detonation network:

[0079] Second-stage detonation network:

[0080] Third-stage detonation network:

[0081] Fourth-stage detonation network:

[0082] For the second type of explosion zone (without side free surfaces):

[0083] First-stage detonation network:

[0084] Second-stage detonation network:

[0085] Third-stage detonation network:

[0086] Fourth-stage detonation network:

[0087] The present invention preferably uses the first and second types of detonation networks described above.

[0088] Application Examples

[0089] The technical solution of the present invention will be further illustrated below through specific application examples.

[0090] Suppose there is an open-pit blasting project with a rock mass wave velocity of... =3m / ms; using the detonation velocity of explosives =4m / ms; the borehole layout parameters are borehole spacing a=4m, row spacing... =3.5m, triangular perforation; charge length =12m; the blast zone has 4 rows of blast holes; single-point detonation is used.

[0091] The stress wave propagation radius is taken as 3 times the isochronous hole spacing for calculation.

[0092] 1. Calculate the isochronous hole spacing

[0093] For triangular hole layout, the isochronous hole spacing and hole spacing Row spacing The relationship is determined by geometric relations.

[0094] First type of detonation network: =6.946m, detonation density coefficient =3.447, which is within the normal range.

[0095] The second type of detonation network: =10.595m, detonation density coefficient =8.02, which is within the normal to slightly high range and is still usable.

[0096] 2. Calculate the maximum detonation time difference.

[0097] When detonated at a single point, =(12~6) / 4=(3~1.5)ms

[0098] =3ms

[0099] =1.5ms

[0100] 3. Calculation base extension

[0101] First type of detonation network:

[0102] =3 × 6.946 / 3 = 6.946 ms

[0103] =1.5 + 6.946 = 8.446ms

[0104] The second type of detonation network:

[0105] =3 × 10.595 / 3 = 10.595 ms

[0106] =1.5 + 10.595 = 12.095ms

[0107] 4. Calculate the inter-hole delay

[0108] The blast zone has a total of 4 rows of blast holes. =4, therefore

[0109] First type of detonation network: =4 × 8.446 = 33.784 ms

[0110] The second type of detonation network: =4 × 12.095 = 48.38 ms

[0111] 5. Calculate the row delay

[0112] For the first type of explosion zone (with a free side surface):

[0113] First-stage detonation network: =33.784 + 8.446 = 42.23ms

[0114] Second-stage detonation network: =2×48.38+12.095=108.855ms

[0115] For the second type of explosion zone (without side free surfaces):

[0116] First-stage detonation network: =2×33.784+8.446=76.014ms

[0117] Second-stage detonation network: =3×48.38+12.095=157.235ms

[0118] Since electronic detonators can usually only be set to integer times, the delay times between holes and between rows are calculated and then rounded to the nearest integer to obtain the actual delay time set for the blasting initiation network in this blasting operation.

[0119] Summary of Implementation Methods

[0120] This invention introduces rock mass wave velocity Explosive detonation velocity Length of charge Physical and mechanical parameters, and the number of rows in the blast zone. Based on geometric parameters such as free surface conditions, a scientific delay time calculation model was established. This method breaks through the limitations of traditional empirical formulas, enabling differentiated design according to specific engineering conditions. It fully leverages the characteristic that the delay time of electronic detonators can be arbitrarily set, effectively controlling blasting vibration while improving blasting effect.

[0121] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for setting up a hole-by-hole initiation network based on electronic detonators, characterized in that, Includes the following steps: Step 1: Obtain the basic parameters of the blasting area. The basic parameters include at least the length of the explosive charge inside the borehole. Explosive detonation velocity Rock mass wave velocity And the hole spacing between adjacent blast holes on the detonation isochrone. ; Step 2: Calculate the maximum time difference for the completion of explosive detonation inside the borehole. ; Step 3: Calculate the stress wave propagation time The The stress wave propagation in the rock mass is 3 to 5 times the hole spacing. The time required to travel the distance, i.e. ; Step 4: Determine the baseline delay time The Maximum time difference With the stress wave propagation time The sum of ; Step 5: Based on the total number of rows in the explosion zone Determine the inter-hole delay time , ; Step 6: Determine the inter-row delay time based on the free surface morphology of the blast zone and the preset detonation network morphology. .

2. The method for setting up a hole-by-hole initiation network based on electronic detonators according to claim 1, characterized in that, In step 2, the maximum time difference between the completion of the explosive detonation inside the borehole is calculated. The method is as follows: Determine the completion time of single-hole detonation based on the initiation method. The range, then ; For single-point detonation, For two-point detonation, .

3. The method for setting up a hole-by-hole initiation network based on electronic detonators according to claim 1, characterized in that, In step 5, the inter-hole delay time The value is no greater than 60ms.

4. The method for setting up a hole-by-hole initiation network based on electronic detonators according to claim 1, characterized in that, In step 6, the blast zone free surface morphology includes a first blast zone morphology with side free surfaces and a second blast zone morphology without side free surfaces and with only front row free surfaces.

5. The method for setting up a hole-by-hole initiation network based on electronic detonators according to claim 4, characterized in that, When the detonation network configuration is the first configuration: For the first type of burst zone with a free side surface, the inter-row delay time ; For the second type of burst zone without a side free surface, the inter-row delay time .

6. The method for setting up a hole-by-hole initiation network based on electronic detonators according to claim 4, characterized in that, When the detonation network configuration is the second configuration: For the first type of burst zone with a free side surface, the inter-row delay time ; For the second type of burst zone without a side free surface, the inter-row delay time .

7. The method for setting up a hole-by-hole initiation network based on electronic detonators according to any one of claims 1-6, characterized in that, The detonation network configuration is either a first configuration with a moderate distribution of downward and rightward thrust components, or a second configuration where the downward thrust component is greater than the rightward thrust component.

8. The method for setting up a hole-by-hole initiation network based on electronic detonators according to claim 1, characterized in that, The basic parameters also include borehole spacing. The hole spacing between adjacent boreholes on the detonation isochrone. Based on the arrangement of boreholes and the hole spacing and row spacing Calculated.

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