Blasting process based on bulk explosive energy gathering structure coupling cutting device

Abstract

The invention discloses a blasting process based on a bulk explosive energy gathering structure coupling cutting device. The process comprises the following steps: firstly, calculating the radiuses of a rock crushing ring and a crack ring under a coupling charging condition; calculating the hole distance between a first detonation hole and a subsequent detonation hole under the coupling charging condition; lithology is obtained through vertical drilling, rock wave impedance is calculated to be matched with explosive wave impedance, and the explosive content is determined; based on the explosive wave impedance calculation result, an energy gathering structure coupling cutting device is machined; connecting an energy gathering structure coupling cutting device; according to the energy-gathered coupling cutting device, the corresponding explosive content can be adopted according to the rock property, excessive large blocks are avoided, coupling charging is carried out in the charging process, the good energy-gathered effect is formed, the change effect on directional cracks in the horizontal direction is remarkable, directional expansion of hole wall surrounding rock cracks is achieved through the energy-gathered principle, and the cutting efficiency is improved. The radius of a crushing area is reduced, the radius of a crack area is increased, the blasting effect is greatly improved, and the blasting process period and cost are reduced.

Description

Technical Field

[0001] The invention relates to the technical field of blasting devices, and in particular to a blasting process based on a bulk explosive energy-gathering structure coupled with a cutting device. Background Art

[0002] When excavating and cutting in rock, the focused blasting technology is used to achieve directional pre-splitting and cutting of rock. It can make full use of the energy of explosives to produce directional cracks, control the expansion of blasting cracks in the set direction, inhibit the generation of cracks in unfavorable directions, reduce the damage to the strength and integrity of surrounding rocks in non-set directions, protect the stability of surrounding rocks in non-set directions, increase the spacing between pre-splitting blastholes, and reduce the unit consumption of pre-splitting explosives. Conventional methods are to use deep hole pre-splitting focused blasting technology such as rock mechanical grooving, slit focused blasting tubes, densely drilled focused blasting tubes, and D-type focused blasting tubes. Energy blasting is an effective means of slope blasting. The deep hole pre-splitting energy-gathering blasting hole needs to be connected by multiple energy-gathering tubes, and the splitting direction of each energy-gathering tube is consistent. However, the existing energy-gathering devices generally adopt special energy-gathering structures or cut slits or drill holes on both sides of the energy-gathering tubes. The energy-gathering tubes with special energy-gathering structures are complicated to process; when loading explosives into the energy-gathering tubes with slits or holes on both sides, there is a problem of explosives leaking from the slits or holes; during blasting, there may be discontinuity in charging between multiple energy-gathering tubes, resulting in residual explosion of explosives in the energy-gathering tubes at the upper part of the borehole.

[0003] Therefore, the prior art still needs to be improved and enhanced. Summary of the invention

[0004] In view of the above-mentioned deficiencies in the prior art, the purpose of the present invention is to provide a blasting process based on a bulk explosive energy-gathering structure coupled with a cutting device, aiming to solve the problem in the prior art that when the energy-gathering device is blasted, the charging is discontinuous between multiple energy-gathering tubes, resulting in residual explosion of explosives in the energy-gathering tubes above the borehole.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A blasting process of a bulk explosive-based energy-gathering structure coupled cutting device, comprising:

[0007] Step 1: Calculate the radius of the rock crushing circle and the fracture circle under coupled charging conditions;

[0008] Step 2: Calculate the hole distance between the first blasting hole and the subsequent blasting holes under coupled charge conditions;

[0009] Step 3: Obtain lithology through vertical drilling, calculate the rock wave impedance to match the explosive wave impedance, and determine the explosive content;

[0010] Step 4: Based on the calculation result of explosive wave impedance in step 3, process the energy-gathering structure coupling cutting device;

[0011] Step 5: Connect the energy-gathering structure to couple the cutting device to meet the requirements of deep hole blasting.

[0012] Furthermore, the calculation of the radius of the rock crushing circle and the fracture circle under the coupled charge condition includes:

[0013] When the detonation wave and rock collide elastically at the interface between explosive and rock, the earliest impact load compressive stress around the blast hole under the condition of continuous charging can be expressed as:

[0014]

[0015] Where: C p is the longitudinal wave velocity in rock; P H is the pressure of the detonation gas product; ρ0 is the density of the rock medium; ρ e is the density of explosives; D is the detonation velocity of explosives; that is:

[0016]

[0017] Where: k is the adiabatic index. For emulsion explosives, the approximate value k = 3 is generally taken;

[0018] Under coupled charging conditions, the detonation velocity D of the explosive is measured and used to calculate the detonation wave pressure of the explosive:

[0019]

[0020] Where, γ is the isentropic index of detonation products;

[0021] The calculation formula of the radius of the crushing circle in the case of coupled charge is:

[0022]

[0023] Where: C p is the longitudinal wave velocity in rock, σ c is the uniaxial static compressive strength of rock; ξ is the loading strain rate, v d is the Poisson's ratio of the rock;

[0024] The crack area under the action of stress wave can refer to the following formula:

[0025]

[0026] Where: c is the compressive strength of rock, λ=v d / (v d +1), v d is the rock Poisson's ratio, r k is the radius of the crushing zone, r b is the blasthole radius, P dis the initial impact pressure.

[0027] Furthermore, the calculation of the hole spacing between the first blast hole and the subsequent blast holes under the coupled charge condition includes:

[0028] The distance between the cut hole and the empty hole is mainly affected by the compensation space, the explosive fragmentation range and the blasthole deviation. The reasonable blasthole spacing needs to meet the blasthole spacing required by the compensation space theory, the blasthole spacing determined by the fragmentation range and the blasthole spacing required by the allowable error range of the drilling deviation theory.

[0029] The compensation space should meet the volume required after the ore and rock are crushed and expanded, and it should satisfy the following relationship:

[0030] S1K≤S1+S2+S3

[0031] Where: S1 is the area of ​​the pre-blast hole; S2 is the area of ​​the empty hole; S3 is the area of ​​the charging hole.

[0032] According to the geometric relationship between the charging hole and the empty hole, the distance relationship between the charging hole and the empty hole can be derived:

[0033]

[0034] Where: L is the distance between the empty hole and the charging hole; d is the diameter of the charging hole; D is the diameter of the empty hole; K is the rock expansion coefficient;

[0035] When the first blast hole forms a slot cavity, a free surface is drilled for the subsequent blast hole. The width of the free surface can be determined by the blasting funnel after the first blast hole is blasted. The clamping coefficient is generally used to represent the clamping effect of the rock. The clamping coefficient conforms to the formula:

[0036]

[0037] Where: Z represents the rock clamping coefficient, W represents the minimum resistance line of the charge, and B represents the length of the blasting free surface;

[0038] In the case of single free surface blasting, the charge amount can be determined by the following formula:

[0039] Q=q(Z)V

[0040] Where: Q is the charge, q(Z) is the unit consumption of explosives, which is a function of the rock clamping coefficient, and V is the volume of the blasted rock;

[0041] The charge form of the slot hole is columnar charge, see the following formula:

[0042]

[0043] As can be seen from the above formula, when Q' is certain, the optimal burden of the blast hole is selected according to the width of the free face to ensure the best cut blasting effect when the blasting funnel is the largest;

[0044] The optimal burden increases with the increase of the free face within a certain range, that is, the optimal burden can be considered as a monotonically increasing function of the free face width, as shown in the formula:

[0045]

[0046] When the width of the free face reaches a certain value, the optimal burden reaches the maximum, that is:

[0047]

[0048] When B < B0, a differential equation can be formed:

[0049]

[0050] where c is a constant, and the solution of the equation gives the formula:

[0051]

[0052] According to experience, c = 1.5, B0 = 0.8, and B is the hole spacing between the first blast hole and the empty hole.

[0053] Furthermore, the obtaining of the lithology through vertical drilling, calculating the matching of the rock wave impedance and the explosive wave impedance, and determining the explosive content include:

[0054] Establishing a relationship model between the drilling rig speed, rock properties, and working parameters of the drilling rig: v = F(P, P 风 , ω, ρ 材 , A, ρ, f, S c , S t , S s )

[0055] In the formula: the pressure P of the drilling rig, the air pressure P 风 , the rotational speed ω of the drilling rig, the material ρ of the drill bit 材 , the shape and size A, the density ρ of the rock, the hardness coefficient f of the rock, the compressive strength S of the rock c , the tensile strength S of the rock t , the shear strength S of the rock s ;

[0056] In actual engineering, when the material and shape of the drill bit are fixed, and the impact pressure, air pressure, and rotational speed of the drilling rig are set as constants, a simplified model is obtained, and the drilling speed of the drilling rig only changes with the rock properties, that is:

[0057] v = K·F(ρ, f, S c , St ,S s )

[0058] The distribution of rock hardness and other properties can be judged from the drilling speed of the drilling rig; the drilling speed can be calculated as follows:

[0059]

[0060] Where: v is the drilling speed of the drilling rig; P is the axial pressure; n is the drill bit speed; D is the borehole diameter; f is the rock strength coefficient;

[0061] From the above drilling speed formula, it can be concluded that as long as the performance index of the drilling rig is fixed and the borehole diameter is fixed, the drilling speed v of the drilling rig can be obtained through field observation, and the Proctor hardness coefficient of the rock can be obtained accordingly. That is to say, the two expressions can be synthesized into a form as follows:

[0062] v=K·g(Jf,D)

[0063]

[0064] Where K is a constant;

[0065] Calculate the explosive capacity; the larger the explosion capacity, the more explosive gas products there are and the higher the work efficiency. The formula is as follows:

[0066]

[0067] Where V 药 is the explosive capacity of the explosive; ∑n j is the total number of moles of gas detonation products; m i is the number of moles of explosive component i; Me i is the molecular weight of explosive component i;

[0068] The approximate theoretical equation of detonation fluid dynamics theory is often used in engineering to estimate the detonation velocity of explosives, such as:

[0069]

[0070] Where D is the detonation velocity; Q v is the ideal explosion heat; K is the local isentropic index of the detonation product;

[0071] The ammonium nitrate content in the explosive component is positively correlated with the detonation heat, detonation velocity, and wave impedance of the explosive; as the ammonium nitrate content increases, the detonation velocity, detonation heat, and wave impedance all increase, and vice versa; as the ammonium nitrate content increases, the detonation capacity decreases, and vice versa;

[0072] The wave impedance of rock P 石 is the density of the rock 石 and the propagation speed of sound waves in the rock mass c 石constitute.

[0073] P 石 =ρ 石 ×c 石 ;

[0074] Calculate the density of the explosive to determine the content of ammonium nitrate, as follows:

[0075] P 石 =P 药

[0076]

[0077] Furthermore, based on the explosive wave impedance calculation result in step 3, processing the energy-gathering structure coupling cutting device includes:

[0078] S1: Use a crystal crusher to crush the mixed ammonium nitrate and sodium nitrate, dissolve the crushed ammonium nitrate in water, and then add a dispersant and stir evenly;

[0079] S2: After the oil phase solid composite material is melted, the oil phase liquid composite material is injected to homogenize the mixture, and then an emulsifier is added, and the temperature is controlled at 85°C; the emulsifier is a polyisobutylene succinimide emulsifier;

[0080] S3: the obtained oil phase solution is mixed with the aqueous phase solution, and a stirring process is performed at a speed of 600 r / min for 3 minutes to obtain colostrum, and then the mixed solution is sent to a static mixer for finishing to obtain latex;

[0081] S4: putting the obtained latex into a cooler and cooling it to 25° C.; adding a sensitizer to the cooled latex to start sensitization, discharging the material while sensitizing, and then filtering it through a filter to obtain explosives;

[0082] S5: the emulsion explosive obtained in step S4 is loaded into a charge cylinder, and then squeezed downward by a mechanical push plate. Under the action of the squeeze, the emulsion explosive is squeezed from the charge cylinder into the energy-gathering tube, thereby achieving coupled charging and obtaining an energy-gathering structure coupled cutting device.

[0083] Furthermore, the step 5 comprises:

[0084] An energy-gathering tube connecting device is used to connect the energy-gathering tubes of the energy-gathering structure coupling cutting device. The energy-gathering tubes are provided with V-shaped energy-gathering grooves at both ends that are evenly distributed at a fixed angle along the tube body axis, and the vertex opening directions of all V-shaped energy-gathering grooves point to the center of the tube body; the tube-to-tube connecting device is provided with corresponding V-shaped protrusions for the V-shaped energy-gathering grooves at both ends, and the inner diameter of the connecting device is the same as the outer diameter of the energy-gathering tube to achieve a close connection. When in use, the bottom of the previous energy-gathering tube and the top of the next energy-gathering tube are placed in the tube-to-tube connecting device, and tape is used to wrap the top and bottom of the tube-to-tube connecting device to ensure that the connection is fixed.

[0085] Furthermore, the wave impedance of rock P 石 is the density of the rock 石 and the propagation speed of sound waves in the rock mass c 石 The propagation speed of sound waves in rock mass is c 石 It can be measured by rock acoustic parameter instrument, the specific steps are as follows:

[0086] S1: Take the rock specimen to be tested, label it and record the specimen height l;

[0087] S2: Zero the instrument, place the measuring probes at both ends of the standard sample, and keep the measuring probes on the same horizontal line;

[0088] S3: Operate the rock acoustic wave detector to record the propagation time t of the elastic wave in the specimen, and calculate and record the rock elastic wave velocity using the following formula:

[0089]

[0090] Wave impedance P of explosive 药 is the density of the explosive ρ 药 and the explosive detonation velocity D;

[0091] P 药 =ρ 药 ×D.

[0092] Furthermore, the obtained latex is placed in a cooler and cooled to 25° C. A sensitizer is added to the cooled latex to start sensitization, and the material is discharged while sensitizing, and then filtered through a filter to obtain explosives including:

[0093] Using NaNO2 as a foaming agent, phosphoric acid, citric acid, etc. as accelerators for chemical sensitization:

[0094] Sodium nitrite meets ammonium nitrate in the latex matrix system to generate unstable ammonium nitrite, namely:

[0095] NH4NO3+NaNO2→NH4NO2+NaNO3

[0096] NH4NO2→N2↑+2H2O

[0097] Emulsion explosives and other water-containing explosives use the above formula to generate microbubbles, and the main gas in the microbubbles is N2; the density of emulsion explosives is adjusted by sensitizers, which is mainly achieved by changing the volume of microbubbles introduced into the explosives. Reasonable consideration of the sensitization temperature and time has a certain effect on promoting bubble generation, and the amount of sensitizer added is reasonably determined to achieve chemical sensitization of emulsion explosives:

[0098] Sensitizer addition amount

[0099] According to the reaction mechanism of sodium nitrite, if more N2 tiny bubbles are to be obtained, the dosage of sodium nitrite can be increased. The calculation formula of the dosage of sensitizer is:

[0100]

[0101] Where: G m is the dosage of sensitizer; ρ B is the designed density of emulsion explosive; V R V is the volume per kg of latex matrix; G is the gas production of the sensitizer.

[0102] The technical solution adopted by the present invention has the following beneficial effects:

[0103] The energy-gathering coupled cutting device proposed in the present invention can adopt corresponding explosive content according to the rock properties to avoid the generation of excessive large pieces, and couple charging is performed during the charging process to form a good energy-gathering effect, which has a significant effect on changing the horizontal directional cracks. The length of the main crack in the horizontal direction is about 8 times the diameter of the blasthole. In the non-energy-gathering direction, part of the energy acts on the energy-gathering tube to reduce the degree of damage to the rock in the non-energy-gathering direction caused by blasting. The secondary cracks generated are 2.2 times the diameter of the blasthole on average. Although some secondary cracks are generated, the damage range in the energy-gathering direction is significantly greater than that in the non-energy-gathering direction. The directional fracturing effect is obvious, which solves the problem of discontinuous charging between multiple energy-gathering tubes when the energy-gathering device is blasted, and avoids causing residual explosion of explosives in the energy-gathering tube at the upper part of the borehole. In addition, the energy-gathering principle is used to realize the directional expansion of cracks in the surrounding rock of the hole wall, reduce the radius of the crushing zone, and increase the radius of the fracture zone, greatly improve the blasting effect, and reduce the cycle and cost of the blasting process. BRIEF DESCRIPTION OF THE DRAWINGS

[0104] Figure 1 This is the blasting process flow chart of the energy-gathering coupled cutting device;

[0105] Figure 2 This is a comparison diagram between the energy-gathering coupling cutting device and the common charge device;

[0106] Figure 3 This is a diagram of the pipe connection device;

[0107] Figure 4 Schematic diagram of the impact effect of the detonation wave;

[0108] Figure 5 This is a schematic diagram of blasting crushing funnel calculation;

[0109] Figure 6 This is a schematic diagram of the wave impedance matching between explosives and rocks;

[0110] Figure 7 It is a schematic diagram of coupled charge;

[0111] Figure 8 Simulated explosion gap expansion diagram for the energy-gathering coupled cutting device. DETAILED DESCRIPTION

[0112] In order to make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0113] In this embodiment, a coupled cutting device based on a bulk explosive energy-gathering structure is proposed. The device can adopt the corresponding explosive content according to the rock properties to avoid the production of excessive large pieces, and couple the charging during the charging process to form a good energy-gathering effect, which has a significant effect on the change of horizontal directional cracks. In addition, the energy-gathering principle is used to achieve directional expansion of cracks in the surrounding rock of the hole wall, reduce the radius of the crushing zone, and increase the radius of the fracture zone, thereby greatly improving the blasting effect and reducing the cycle and cost of the blasting process.

[0114] In this embodiment, the blasting process of the energy-gathering structure coupled cutting device based on bulk explosives includes the following steps:

[0115] Step 1: Calculate the radius of the rock crushing circle and the fracture circle under coupled charging conditions.

[0116] When the detonation wave and the rock collide elastically at the interface between the explosive and the rock, the earliest impact load compressive stress around the blast hole under the condition of continuous charging can be expressed by formula (1):

[0117]

[0118] Where: C p is the longitudinal wave velocity in rock; P H is the pressure of the detonation gas product; ρ0 is the density of the rock medium; ρ e is the density of explosive; D is the detonation velocity of explosive.

[0119]

[0120] Where: k is the adiabatic index, and its calculation formula is shown in formula (3):

[0121]

[0122] Where: (1+a) is the specific energy of the specific heat of the detonation gas under laboratory conditions; G is the detonation heat of the detonation gas product part. When the density of the explosive is very small, k = 1 + a, which is the ideal state, and k is usually taken as 4 / 3.

[0123] After simplified calculation, the relationship is shown in formula (4):

[0124] k=1.9+0.6ρ e (4)

[0125] For most emulsion explosives, the approximate value k=3 is generally taken in the calculation.

[0126] Under coupled charge conditions, the impact effect of the detonation wave is shown in the figure.

[0127] The detonation velocity D of explosives is relatively easy to test, so the detonation wave pressure of explosives can be obtained by testing the detonation velocity and calculating. The calculation formula is shown in formula (5):

[0128]

[0129] Where γ is the isentropic index of the detonation products.

[0130] According to the propagation law of shock waves in two different media, the transmission coefficient T of the detonation wave propagating to the rock mass can be calculated, as shown in formula (6):

[0131]

[0132] Where, T is the transmission coefficient; ρ0 is the rock density; C p is the velocity of longitudinal waves in rocks.

[0133] Therefore, the maximum pore wall pressure can be calculated by formula (7):

[0134]

[0135] like Figure 4 As shown in the figure, in most cases during blasting, the radius of curvature of the detonation wave is greater than the radius of the blasthole. The detonation wave collides with the hole wall to form a certain incident angle. The pressure at the interface between the explosive and the hole wall is not only related to the medium properties of the explosive and the hole wall, but also to the incident angle when the detonation wave reaches the hole wall interface. related.

[0136] When the detonation wave acts on Figure 4 When the hole wall is at point A, the geometric relationship shows:

[0137]

[0138] Where d is the diameter of the blast hole and R is the radius of curvature of the detonation wave.

[0139] When the detonation wave acts on point B at the bottom of the hole, the geometric relationship shows that:

[0140]

[0141] Where d1 is the vertical distance between point B at the bottom of the hole and the hole wall.

[0142] When d1=d / 2, The detonation wave is incident vertically at the exact center of the hole bottom.

[0143] Therefore, when the incident angle is The actual maximum pressure of the hole wall is:

[0144]

[0145] In the formula, is the oblique reflection coefficient of the detonation wave.

[0146] Under certain conditions, the explosion of explosives first stimulates a shock wave in the rock mass, which then rapidly decays into a stress wave. The explosion shock wave decays geometrically with distance, and the stress peak value decreases rapidly in geometric series with increasing distance. The relationship between the radial stress peak value and the distance can be expressed in the form of formula (11):

[0147]

[0148] In the formula, To compare the distance, a is the stress wave attenuation index; r is the distance from the measuring point to the center of the charge; r0 is the radius of the charge.

[0149] Referring to the previous empirical formula, the empirical relationship between the stress attenuation index and the Poisson's ratio of rock is as follows:

[0150]

[0151] Where: the second term on the right is “+” for shock wave and “-” for stress wave; v d is the Poisson's ratio of rock.

[0152] According to the current research status, it can be considered that v d The relationship in accordance with formula (13) is:

[0153] v d =0.8v (13)

[0154] Where v is the static Poisson's ratio of rock.

[0155] The absolute value of the peak value of the tangential tensile stress after the explosion of the explosive charge can be expressed by the peak value of the radial compressive stress, which can be expressed by formula (14):

[0156] σ θ =bσ r (14)

[0157]

[0158] Where b is the lateral action index.

[0159] In engineering blasting, rock is a typical brittle material, and its compressive strength is significantly higher than its tensile strength. According to the above two equations, we can see that σ r >σθ、σ r >σ z .

[0160] Therefore, according to the first strength theory, it can be considered that the stress intensity at any point of the rock conforms to the relationship of formula (16):

[0161] σ1=σ r (16)

[0162] Studies have shown that the crushing zone in rock blasting is the rock under compressive failure, while the fracture zone is the rock under tensile failure. If the tensile strength σ1 of the rock satisfies equations (17) and (18), the rock failure is:

[0163] σ1>σ0(17)

[0164]

[0165] Where: σ0 is the failure strength of rock under uniaxial load; σ cd is the uniaxial dynamic compressive strength of rock; σ td is the uniaxial dynamic tensile strength of rock.

[0166] The dynamic compressive strength of rock increases with the increase of loading strain rate, but different rocks have different sensitivities to strain. According to existing research, for common blasting rocks, the relationship between the dynamic compressive strength and the static compressive strength of rock can be approximately expressed uniformly as shown in formula (19):

[0167]

[0168] Where: c is the uniaxial static compressive strength of rock; ξ is the loading strain rate.

[0169] The loading rate of rock is between 10 and 10 4 s -1 In the crushing circle, the loading rate is relatively high, generally 100 to 10 4s -1 , outside the crushing circle, the loading rate is reduced, taking 10 to 100s -1 .

[0170] Combining equations (6) to (16), the calculation formula for the radius of the crushing circle under coupled charge conditions can be obtained as shown in equation (20):

[0171]

[0172] The crack area under the action of stress wave can refer to formula (21):

[0173]

[0174] Where: c is the compressive strength of rock, λ=v d / (v d +1).

[0175] Experience shows that the drilling speed often decreases with the increase of hole diameter during rock drilling. Within a certain range, the number of blastholes will not decrease significantly with the increase of hole diameter. When the diameter of the empty hole is larger than the diameter of the slot hole and satisfies formula (22), not only can the rock between the empty hole and the slot hole be broken, but also a breaking funnel can be formed, such as Figure 5 As shown:

[0176]

[0177] In the formula: D is the diameter of the empty hole; d is the diameter of the slot hole; a is the rock blasting crushing angle. When vertical slotting is used, a>30° is required.

[0178] Step 2: Calculate the hole spacing between the first blasting hole and subsequent blasting holes under coupled charging conditions.

[0179] The distance between the slot hole and the empty hole is mainly affected by three aspects: compensation space, explosive crushing range and blasthole deflection. First, in order to prevent the occurrence of regenerated rock, the slot cavity space must meet the volume requirements of rock mass expansion during blasting; second, in order to prevent the punching phenomenon caused by too much or too little explosives and the inability to fully blast the rock mass, the energy generated by the explosive blasting must meet the energy requirements for the blasting of the rock mass between holes; third, in order to prevent the occurrence of mutual penetration between adjacent blastholes, the spacing between drill holes must be greater than the deflection during drilling. Therefore, a reasonable blasthole spacing needs to simultaneously meet the blasthole spacing required by the compensation space theory, the blasthole spacing determined according to the crushing range, and the blasthole spacing required by the allowable error range of the drilling deflection theory.

[0180] The compensation space should meet the volume required after the ore and rock are crushed and expanded, otherwise blockage will occur, thus affecting the blasting effect.

[0181] It should satisfy the following relationship:

[0182] S1K≤S1+S2+S3 (23)

[0183] Where: S1 is the area of ​​the pre-blast hole; S2 is the area of ​​the empty hole; S3 is the area of ​​the charging hole.

[0184] According to the geometric relationship between the charging hole and the empty hole, the distance relationship between the charging hole and the empty hole can be derived:

[0185]

[0186] Where: L is the distance between the empty hole and the charging hole; d is the diameter of the charging hole; D is the diameter of the empty hole; K is the rock expansion coefficient.

[0187] When the first blast hole forms a slot cavity, a free surface is bored for the subsequent blast hole. The width of the free surface can be determined by the blasting funnel after the first blast hole is blasted. The clamping coefficient is generally used to represent the clamping effect of the rock. The clamping coefficient conforms to formula (26):

[0188]

[0189] Where: Z represents the rock clamping coefficient, W represents the minimum resistance line of the charge, and B represents the length of the blasting free surface. In the case of single free surface blasting, the charge amount can be determined by formula (27):

[0190] Q=q(Z)V (27)

[0191] Where: Q is the charge, q(Z) is the unit consumption of explosives, which is a function of the rock clamping coefficient, and V is the volume of the blasted rock.

[0192] The charge form of the slot hole is columnar charge, see formula (28):

[0193]

[0194] It can be seen from the above formula that when Q' is constant, the optimal resistance line of the blasthole is selected according to the width of the free surface to ensure that the best effect of slot blasting is achieved when the blasting funnel is the largest.

[0195] The optimal resistance line increases with the increase of the free surface within a certain range. It can be considered that the optimal resistance line is a monotonically increasing function of the free surface width, as shown in formula (29):

[0196]

[0197] When the free surface width reaches a certain value, the optimal resistance line reaches the maximum, which is formula (30):

[0198]

[0199] When B < B0, a differential equation can be formed:

[0200]

[0201] where c is a constant. Solving the equation gives the formula:

[0202]

[0203] According to experience, take c = 1.5, B0 = 0.8, and B is the hole spacing between the first blast hole and the empty hole.

[0204] Step 3: Obtain the lithology through vertical drilling, calculate the matching of the rock wave impedance and the explosive wave impedance, and determine the explosive content.

[0205] During the rock drilling process of the drilling machine, there are many factors affecting the drilling speed of the rock drill and they are very complex. The main ones are the pressure P of the drill rig, the wind pressure P 风 , the rotational speed ω of the drill rig, the material ρ of the drill bit 材 and its shape and size A, the drilling depth, the properties of the rock and the geological structure of the rock mass, as well as the technical level of the operator, etc. The properties of the rock include the density ρ of the rock, the hardness coefficient f of the rock, the compressive strength S of the rock c , the tensile strength S of the rock t , the shear strength S of the rock s etc. Here, a relationship model between the drill rig speed, the rock properties, and the working parameters of the drill rig is established. Thus, the following functional relationship can be established:

[0206] v = F(P, P 风 , ω, ρ 材 , A, ρ, f, S c , S t , S s ) (33)

[0207] Furthermore, due to being affected by various conditions simultaneously, the working parameters of the drill rig such as pressure, wind pressure, rotational speed, etc. may not be fixed values, but their changes are very small and basically fluctuate within a very small range, and these small fluctuations are all correlated with the properties of the rock. In actual engineering, the material and shape of the drill bit can be fixed, and the impact pressure, wind pressure, and rotational speed of the drill rig are set as constants. Thus, a simplified model can be obtained: the drilling speed of the drill rig only changes with the properties of the rock, that is:

[0208] v = K·F(p, f, S c , S t , S s ) (34)

[0209] Finally, considering the level of operating skills, the distribution of rock hardness and other properties can be judged from the drilling speed of the drill rig; the drilling speed can be calculated as follows:

[0210]

[0211] Where: v is the drilling speed of the drilling rig; P is the axial pressure; n is the drill bit speed; D is the borehole diameter; f is the rock strength coefficient.

[0212] Furthermore, from the above drilling speed formula, it can be concluded that as long as the performance index of the drilling rig is fixed and the borehole diameter is fixed, the drilling speed v of the drilling rig can be obtained through field observation, and the Proctor hardness coefficient of the rock can be obtained accordingly. That is to say, the two expressions can be synthesized into a form as follows:

[0213] v=K·g(f,D) (36)

[0214]

[0215] Where K is a constant.

[0216] Furthermore, the explosion capacity of the explosive is calculated; the larger the explosion capacity value, the more explosion gas products there are and the higher the work efficiency. The explosion capacity is calculated using formula (38).

[0217]

[0218] Where V 药 is the explosive capacity of the explosive; ∑n j is the total number of moles of gas detonation products; m i is the number of moles of explosive component i; Me i is the molecular weight of component i of the explosive.

[0219] Furthermore, the approximate theoretical equation of detonation fluid dynamics theory is often used in engineering to estimate the detonation velocity of explosives, such as formula (39):

[0220]

[0221] Where D is the detonation velocity; Q v is the ideal explosion heat; K is the local isentropic index of detonation products.

[0222] Furthermore, according to wave impedance theory, the wave impedance of explosives is the product of the density of explosives and the detonation velocity. According to the actual engineering situation, the density of mixed emulsion explosives is usually controlled between 1.15-1.25g / cm3. The theoretical detonation velocity of explosives with different formulations is obtained by calculation.

[0223] Furthermore, summarizing previous engineering experience, the ammonium nitrate content in the explosive component is positively correlated with the explosion heat, explosion velocity, and explosive wave impedance. As the ammonium nitrate content increases, the explosion velocity, explosion heat, and wave impedance all increase, and vice versa; as the ammonium nitrate content increases, the explosion capacity decreases, and vice versa.

[0224] Furthermore, the wave impedance of rock P 石 is the density of the rock 石 and the propagation speed of sound waves in the rock mass c 石 constitute.

[0225] P 石 =ρ 石 ×c 石 (40)

[0226] The propagation speed of sound waves in rock mass is c 石 It can be measured by rock acoustic parameter instrument, the specific steps are as follows:

[0227] S1: Take the rock specimen to be tested, label it and record the specimen height l;

[0228] S2: Zero the instrument, place the measuring probes at both ends of the standard sample, and keep the measuring probes on the same horizontal line;

[0229] S3: Operate the rock acoustic wave detector to record the propagation time t of the elastic wave in the specimen, and use formula (41) to calculate and record the rock elastic wave velocity.

[0230]

[0231] Wave impedance P of explosive 药 is the density of the explosive ρ 药 And the explosive detonation velocity D.

[0232] P 药 =ρ 药 ×D(42)

[0233] Furthermore, the impedance matching theory holds that when the wave impedance of the explosive and the rock are close to or equal, a good blasting effect can be achieved. When the two are equal, the highest energy transfer coefficient is achieved, and the detonation pressure generated by the explosion of the explosive can be completely transmitted into the rock.

[0234] Furthermore, the physical and chemical properties and detonation performance of explosives can directly affect their blasting action and effect. The density and detonation velocity of explosives determine their wave impedance, which are closely related to the explosive heat, explosion pressure, and work capacity of explosives. In order to cause explosion crack expansion in high-strength and high-impedance rocks, an explosion stress wave with a higher pressure peak is required; for medium-impedance rocks, the explosion stress wave peak should not be too high, but the action time should be increased; for low-impedance rocks, the destruction of rocks mainly depends on the static pressure of high-temperature and high-pressure gases, and the stress wave peak should be weakened as much as possible. Based on this, from the perspective of economy and blasting effect, in order to improve the energy transfer efficiency of explosives, such as Figure 6 As shown, the wave impedance of the explosive and the rock should be matched, and the closer the two are, the better the effect.

[0235] Furthermore, the density of the explosive can be calculated to determine the content of ammonium nitrate, as shown in formula (44):

[0236] P 石 =P 药 (43)

[0237]

[0238] Step 4: Based on the calculation results of explosive wave impedance in step 3, process the energy-gathering structure coupling cutting device.

[0239] Emulsion explosive is a W / 0 latex type water-resistant industrial explosive prepared by emulsification technology. It uses oxidant aqueous solution micro-droplets as dispersed phase, suspended in a continuous medium composed of oil phase materials containing dispersed bubbles or porous materials such as expanded perlite. Emulsion explosive components can be summarized into four main parts: water phase materials, oil phase materials, emulsifiers and sensitizers. Some emulsion explosives will also add other additives according to different needs to improve or adjust the physical and chemical properties and detonation performance of emulsion explosives.

[0240] Furthermore, industrial explosive oxidants should meet the following conditions: rich in oxygen, with a high effective oxygen content; cheap and readily available, with a wide range of sources and convenient processing; moderate sensitivity and good stability; more gaseous products during the explosion reaction and high heat release;

[0241] Furthermore, the oxides that meet the relevant requirements mainly include salts, metal oxides and liquid oxidants.

[0242] Furthermore, among the above-mentioned related oxides, ammonium nitrate has the advantages of rich oxygen content, good stability, and more gaseous products. The explosives made from it are powerful, moderately sensitive, and have the advantages of wide sources and low prices. Ammonium nitrate has become the main raw material for industrial explosive oxidants. At normal temperature and pressure, ammonium nitrate is a white crystal. When the temperature range is -16.9 to 169.6°C, there are a variety of crystal structures. Crystallization occurs at 32.3°C, so ammonium nitrate is prone to moisture absorption and agglomeration, which in turn affects the various properties of industrial explosives.

[0243] Further, the specific steps of the blasting process are as follows: Figure 1 shown.

[0244] S1: Use a crystal crusher to crush the mixed ammonium nitrate and sodium nitrate, dissolve the crushed ammonium nitrate in water, and then add a dispersant and stir evenly.

[0245] Furthermore, the molecular formula of ammonium nitrate is NH4NO3, and the relative molecular weight is 80, which can be represented by the abbreviation code AN. Due to its rich oxygen content, wide source, low price and moderate sensitivity, it is the most important oxidant and basic component in industrial explosives. Under normal temperature and pressure, pure ammonium nitrate is a white crystal without crystal water, and industrial ammonium nitrate is slightly light yellow due to a small amount of impurities. Ammonium nitrate can be made into a variety of shapes, and industrial explosives generally use powdered, granular and porous granular ammonium nitrate. Ammonium nitrate is very soluble in water, and its solubility increases with increasing temperature.

[0246] Furthermore, sodium nitrate is not explosive, but has a high effective oxygen content and a small temperature coefficient of dissolution in water, which can effectively reduce the crystallization point of ammonium nitrate in aqueous solution. However, due to the high cost of sodium nitrate and the fact that the sodium oxide produced after the explosion is a solid product that reduces the power of industrial explosives, it is difficult to use it as the main oxidant of industrial explosives, and is only suitable as an auxiliary oxidant added to the oxidant aqueous solution to achieve the purpose of reducing the crystallization point of ammonium nitrate in aqueous solution and increasing the effective oxygen content.

[0247] Further, the mixture is heated in a water bath and stirred with a stirrer to dissolve the ammonium nitrate to obtain an aqueous phase solution.

[0248] S2: After the oil phase solid composite material is melted, the oil phase liquid composite material is injected to homogenize the mixture, and then an emulsifier is added. The temperature is controlled at 85° C. The emulsifier is a polyisobutylene succinimide emulsifier.

[0249] Furthermore, according to the emulsion stability theory and production practice, the quality of the oil phase material is directly related to the emulsification effect, the oil film strength and the stability of the product performance. In order to facilitate emulsification and solidification, the oil phase material should not only be solid at room temperature and have a certain toughness, but also be easy to form a liquid with low viscosity and good fluidity when heated, and have a certain fluidity when cooled and solidified, so that the oil film has a certain self-repairing ability. Therefore, the appropriate selection and correct use of oil phase materials with high melting point, high viscosity, high toughness, high hardness and matching with emulsifiers can increase the strength and density of the latex matrix interface film, prevent the agglomeration of the dispersed phase, and improve the stability of the performance of powdered emulsion explosive products.

[0250] Furthermore, polyisobutylene succinimide emulsifier is a brown-red viscous oily body, which is clean and transparent, with a specific gravity of 0.9g / cm2. It is hardly soluble in water, but easily soluble in oil and organic solvents. It is a non-ionic surfactant with excellent emulsification performance. Due to its wide source of raw materials and simple synthesis process, it has been widely used in the production of emulsion explosives and is the best emulsifier for the production of powdered emulsion explosives.

[0251] Furthermore, polyisobutylene succinimides have a macromolecular framework structure, which can be dissolved in oil and organic solvents in the form of single molecules, and do not form micelles during the emulsification process. Unlike ionic surfactants, polyisobutylene succinimides do not have hydrophilic and lipophilic groups. During the emulsification process, the non-polar parts at both ends of it dissolve into the oil, and the polar part in the middle extends into the water phase to produce molecular bending, forming a dense, mechanically strong three-dimensional barrier film between the oil and water phases. This film has a certain viscoelasticity, which is why the latex matrix is ​​not easily destroyed during the spray powdering process. Polyisobutylene succinimides can reduce the interfacial tension of paraffin / ammonium nitrate saturated aqueous solution to 12mN / m, and the detonation velocity increases accordingly with the reduction of interfacial tension, which shows that the more thermodynamically stable the latex system is, the better the detonation performance of its product. Therefore, polyisobutylene succinimides emulsifiers have become the first choice for powdered emulsion explosives.

[0252] Furthermore, the oil phase liquid composite material is melted according to the proportion of the oil phase components and prepared into an oil phase solution that meets the technical requirements.

[0253] S3: the obtained oil phase solution is mixed with the aqueous phase solution, and a stirring process is performed at a speed of 600 r / min for 3 min to obtain colostrum, and then the mixed solution is sent to a static mixer for finishing to obtain latex;

[0254] Furthermore, as the key process for forming the latex matrix, the determination and control of process parameters are directly related to the quality of the latex matrix and the stability of product performance. Emulsion theory shows that the stability of the latex matrix depends on the stability of the latex particle oil film, and the stability of the oil film is related to the properties of the oil phase material and the film-forming mechanism. Its important indicator is the size and distribution of the dispersed phase particles of the emulsion. Limited by the emulsion preparation method, the emulsification temperature and the speed of the emulsifier are two important process control parameters that affect the emulsification quality.

[0255] Furthermore, in the preparation process of the latex matrix, if the emulsification temperature is lower than the precipitation point of the aqueous solution and the melting point of the oil phase material, the W / O type latex matrix cannot be formed well. The emulsification temperature depends on the temperature of the water and oil phases. If the temperature of the water phase is too low, the ammonium nitrate solution may precipitate in the early stage of emulsification, destroying the water-oil interface film; if the temperature of the oil phase is too low, the viscosity of the oil phase increases, which reduces the area of ​​the oil film formed under the same shear force, and the small droplets of the water phase cannot be fully covered during emulsification. If the temperature of the water and oil phases is too high, on the one hand, it will increase the insecurity of production, and on the other hand, it will weaken the adsorption capacity of the emulsifier molecules on the two phases, making the interface film of the oil-water two phases not strong enough, resulting in weakened stability of the latex matrix.

[0256] Furthermore, according to production practice experience, when the pipeline insulation conditions are very good, the insulation temperature of the water and oil phases should generally be 10 to 20°C higher than the crystallization point.

[0257] Further, the formation of latex matrix mainly relies on the mechanical stirring of emulsifier and the directional adsorption of surfactant. When the latex matrix preparation method is determined, the change of latex matrix particle size can only be achieved by adjusting the emulsifier operating parameters. In the emulsification and stirring process, as the stirring speed increases, the shear force generated by stirring is greater, and the diameter of the dispersed droplets of latex particles becomes smaller, so appropriately increasing the emulsifier speed is an important way to improve matrix stability. More importantly, latex particles with smaller diameters are not easily destroyed by the shear force generated by the nozzle compressed air in the spray powder making process. Therefore, the rotating speed is 600r / min.

[0258] The latex matrix does not have detonator sensitivity and its density is generally between 1.35 and 1.55 g·cm -3 In order to introduce microbubbles as hot spots and improve the sensitivity of emulsion explosives, it is necessary to add a sensitizer that can introduce a large number of microbubbles into the latex matrix. The introduced microbubbles can adjust the density of the emulsion explosive within a certain range and keep it within an appropriate range.

[0259] S4: The obtained latex is placed in a cooler and cooled to 25° C. A sensitizer is added to the cooled latex to start sensitization, and the material is discharged while sensitizing, and then filtered through a filter to obtain explosives;

[0260] Furthermore, most of the domestically produced emulsion explosives adopt chemical sensitization, which is simple, fast and low-cost. The emulsion explosives produced have dense microbubbles and many hot spots. The detonation speed and intensity are high and the detonation power is strong. Generally, NaNO2 is used as a foaming agent and phosphoric acid, citric acid, etc. are used as promoters for chemical sensitization.

[0261] Sodium nitrite meets ammonium nitrate in the latex matrix system to generate unstable ammonium nitrite, namely:

[0262] NH4NO3+NaNO2→NH4NO2+NaNO3 (45)

[0263] NH4NO2→N2↑+2H2O (46)

[0264] Furthermore, water-containing explosives such as emulsion explosives use equations (45) and (46) to generate microbubbles, and the main gas in the microbubbles is N2. The density of emulsion explosives is adjusted by using sensitizers, which is mainly achieved by changing the volume of microbubbles introduced into the explosives. The main factors affecting the volume of introduced microbubbles include the following aspects:

[0265] 1) Amount of sensitizer added

[0266] According to the reaction mechanism of sodium nitrite, if more N2 tiny bubbles are to be obtained, the dosage of sodium nitrite can be increased. The calculation formula of the dosage of sensitizer is:

[0267]

[0268] Where: G m is the dosage of sensitizer; ρ B is the designed density of emulsion explosive; V R V is the volume per kg of latex matrix; G is the gas production of the sensitizer.

[0269] Furthermore, the theoretical dosage of sensitizer for a given emulsion explosive density can be calculated based on formula (44). In order to reduce the influence of sensitization temperature and sensitization time, a certain amount of loss needs to be added. After comprehensive consideration, the final dosage is obtained.

[0270] 2) Sensitization temperature and time

[0271] In summary, the chemical sensitization process of emulsion explosives can be mainly divided into three stages: mass transfer of sensitizer, gas generation by chemical reaction, and formation of bubbles due to gas diffusion obstruction. The number of microbubbles formed determines the density of emulsion explosives, while the foaming rate, gas generation and solid foaming ability affect the formation of bubbles. The viscosity of the latex matrix changes with temperature. Generally speaking, with the increase of temperature, the viscosity of the latex matrix decreases, and the mass transfer process of the sensitizer in the latex matrix accelerates; at the same time, with the increase of temperature, the chemical reaction rate of NaNO2 to generate bubbles increases, that is, a higher sensitization temperature is conducive to the mass transfer of the sensitizer and the generation of gas by chemical reaction. However, in the stage of gas diffusion obstruction to form bubbles, the decrease in the viscosity of the latex matrix caused by the higher temperature will make it difficult for the generated gas micro-groups to coexist with the latex matrix. The lower the viscosity of the latex matrix, the smaller the resistance, the faster the gas diffusion, and the solid foam and stabilizing foam ability of the latex matrix are reduced. Therefore, reasonable consideration of the sensitization temperature and time has a certain effect on promoting bubble generation.

[0272] S5: The emulsion explosive obtained in step S4 is loaded into a charge cylinder, and then squeezed downward by a mechanical push plate. Under the action of the squeeze, the emulsion explosive is squeezed from the charge cylinder into the energy-gathering tube to achieve coupled charging, such as Figure 7 The specific operations are as follows:

[0273] Further, a charge cylinder is placed, and the produced emulsion explosive is loaded into the cylinder corresponding to the charge groove of the sleeve;

[0274] Further, after the charge slots are aligned with the emulsion explosive, a mechanical push plate is installed in the cylinder at the top of the cylinder;

[0275] Further, the energy-gathering tube is placed under the cylinder, and the charge position is determined by aligning the energy-gathering hole;

[0276] Furthermore, the push plate is started and slowly pushed downward to form extrusion, so that the explosive is squeezed into the energy-gathering tube in accordance with the tube wall, thereby realizing coupled charging.

[0277] Furthermore, after the charge is loaded, use a tool to smooth the residual emulsion explosive on the top and bottom surfaces of the energy-gathering tube to keep the top and bottom flat. Figure 2 (a) shown.

[0278] This step is easy to operate and can meet the requirement of interval charging, which is more practical.

[0279] Step 5: Connect the energy-gathering tube to meet the requirements of deep hole blasting.

[0280] Further, the pipe connection device is as follows Figure 3As shown, the energy-gathering tube connection device is used to couple the charge energy-gathering tubes for effective connection. The energy-gathering tubes are provided with V-shaped energy-gathering grooves at both ends that are evenly distributed at a fixed angle along the tube body axis, and the vertex opening directions of all V-shaped energy-gathering grooves point to the center of the tube body. The inter-tube connection device is provided with corresponding V-shaped protrusions for the V-shaped energy-gathering grooves at both ends. The inner diameter of the connection device is the same as the outer diameter of the energy-gathering tube to achieve a close connection. When in use, the bottom of the previous energy-gathering tube and the top of the next energy-gathering tube are placed in the inter-tube connection device, and the top and bottom of the inter-tube connection device are wrapped with tape to ensure that the connection is fixed.

[0281] From the above content, it can be seen that the present invention provides a blasting process of bulk explosives and energy-gathering structure coupled cutting device, which can solve (1) the conventional uncoupled charge such as Figure 2 (b) It is difficult to shape the explosive roll into a concentrated shape, and the concentrated effect is weak. (2) The blasting site does not adopt the corresponding explosive content according to the rock properties, resulting in a high rate of large blocks. (3) The principle of concentrated blasting is used to improve the explosive effect, increase the hole spacing, save drilling costs and detonating cord costs, and achieve cost reduction and efficiency improvement.

[0282] Figure 8 This is a diagram of the simulated blasting crack expansion of the energy-focusing coupled cutting device. It can be clearly seen from the damage around the blasthole after blasting and the crack expansion that the energy-focusing coupled cutting device proposed in the present invention has a significant effect on changing the horizontal directional cracks. The length of the main crack in the horizontal direction is about 8 times the diameter of the blasthole. In the non-energy-focusing direction, part of the energy acts on the energy-focusing tube, reducing the degree of damage to the rock in the non-energy-focusing direction caused by blasting. The secondary cracks generated are 2.2 times the diameter of the blasthole on average. Although some secondary cracks are generated, the damage range in the energy-focusing direction is significantly greater than that in the non-energy-focusing direction, and the directional fracturing effect is obvious.

[0283] Example 1: Cost Analysis and Comparison of Ordinary Blasting and Focused Energy Blasting

[0284] Furthermore, taking a real blasting project as an example, the total volume of each blasting is 1200m 3 The horizontal pre-splitting hole depth is 16m, the conventional pre-splitting blasting hole distance is 60cm, a total of 40 holes, and the concentrated pre-splitting blasting hole distance is 200cm, a total of 12 holes. The drilling and related costs are analyzed and compared.

[0285] 1) Costs related to ordinary pre-splitting blasting

[0286] ① Drilling:

[0287] Total drilling depth: 40 (holes) × 16 (m) = 640m.

[0288] The drilling cost is 35 yuan / m per hole, so 640 (m) × 35 (yuan / m) = 22,400 yuan.

[0289] ② Explosives: 640 (m) × 0.36 (kg / m) × 12 (yuan / kg) = 2764.8 yuan.

[0290] ③ Detonating cord: 40 (pieces) × 16 (m) × 6 (yuan / m) = 3840 yuan.

[0291] ④Labor cost: 640(m) / 180×150(yuan / person)=533.33 yuan.

[0292] ⑤Material cost: 40 (pieces) × 16 (m) × 0.6 (yuan / m) = 384 yuan.

[0293] 2) Costs related to energy pre-splitting blasting

[0294] Total drilling depth: 12 (holes) × 16 (m) = 192m.

[0295] The drilling cost is 35 yuan / m per hole, so 192 (m) × 35 (yuan / m) = 6720 yuan.

[0296] ② Explosives: 192 (m) × 0.36 (kg / m) × 12 (yuan / kg) = 829.44 yuan.

[0297] ③ Detonating cord: 12 (pieces) × 16 (m) × 6 (yuan / m) = 1152 yuan.

[0298] ④Labor cost: 192(m) / 150×200(yuan / person)=256 yuan.

[0299] ⑤Material cost: 12 (pieces) × 16 (m) × 5 (yuan / m) = 960 yuan.

[0300] 3) Cost comparison analysis:

[0301] The cost of ordinary pre-splitting blasting is 22400+2764.8+3840+533.33+384=29922.13 yuan; the cost of concentrated energy pre-splitting blasting is 6720+829.44+1152+256+960=9914.44. Through comparative analysis, it can be concluded that the use of concentrated energy pre-splitting blasting can not only improve the explosive effect of explosives and increase the hole spacing, but also save drilling costs and detonating cord costs, thereby reducing costs and increasing efficiency.

[0302] Those skilled in the art will readily appreciate other embodiments of the present invention after considering the specification and practicing the schemes disclosed herein. The present invention is intended to cover any variations, uses or adaptations of the present invention that follow the general principles of the present invention and include common knowledge or customary techniques in the art that are not disclosed in this disclosure. The description and examples are to be considered exemplary only, and the true scope and spirit of the present invention are indicated by the claims.

Claims

1. A blasting process based on bulk explosives and a shaped energy structure coupled cutting device, characterized in that: Including: Step 1: Calculate the radius of the crushed zone and the crack zone of the rock under the condition of coupled charge; Step 2: Calculate the hole spacing of the first blast hole and subsequent blast holes under the condition of coupled charge; Step 3: Obtain the lithology through vertical drilling, calculate the matching of the wave impedance of the rock and the wave impedance of the explosive, and determine the explosive content; Step 4: Based on the calculation result of the wave impedance of the explosive in Step 3, process the coupled cutting device with a shaped charge structure; Step 5: Connect the coupled cutting device with a shaped charge structure to meet the requirements of deep hole blasting.

2. The blasting process of the energy-gathering structure coupled cutting device based on bulk explosives according to claim 1 is characterized in that: The calculation of the radius of the crushed zone and the crack zone of the rock under the condition of coupled charge includes: When an elastic collision occurs between the detonation wave and the rock at the interface between the explosive and the rock, and the charging structure is a continuous charge condition, the compressive stress of the impact load that first appears around the blast hole can be expressed as: Where: C p is the longitudinal wave velocity in rock; P H is the pressure of the detonation gas product; ρ0 is the density of the rock medium; ρ e is the density of explosives; D is the detonation velocity of explosives; that is: In the formula: k is the adiabatic index. For emulsion explosives, an approximate value of k = 3 is generally taken; Under the condition of coupled charge, measure and use the detonation velocity D of the explosive, and the detonation wave pressure of the explosive can be calculated; In the formula, γ is the isentropic index of the detonation products; The formula for calculating the radius of the crushed zone in the case of coupled charge is: Where: C p is the longitudinal wave velocity in rock, σ c is the uniaxial static compressive strength of rock; ξ is the loading strain rate, v d is the Poisson's ratio of the rock; The crack zone under the action of the stress wave can refer to the following formula: Where: c is the compressive strength of rock, λ=v d / (v d +1), v d is the Poisson's ratio of the rock, r k is the radius of the crushing zone, r b is the blasthole radius, P d is the initial impact pressure.

3. The blasting process of the energy-gathering structure coupled cutting device based on bulk explosives according to claim 1 is characterized in that: The calculation of the hole spacing of the first blast hole and subsequent blast holes under the condition of coupled charge includes: The distance between the cut hole and the empty hole is mainly affected by three aspects: the compensation space, the fragmentation range of the explosive, and the deviation of the blast hole. A reasonable blast hole spacing needs to simultaneously meet the blast hole spacing required by the compensation space theory, the blast hole spacing determined according to the fragmentation range, and the blast hole spacing required according to the allowable error range of the drilling deviation theory; The compensation space should meet the volume required after the ore and rock expand, and it should satisfy the following relationship: S1K ≤ S1 + S2 + S3 In the formula: S1 is the area of the pre-blast hole; S2 is the area of the empty hole; S3 is the area of the charged hole; According to the geometric relationship between the charged hole and the empty hole spacing, the distance relationship formula between the charged hole and the empty hole can be deduced: In the formula: L is the distance between the empty hole and the charged hole; d is the diameter of the charged hole; D is the diameter of the empty hole; K is the expansion coefficient of the rock; When the first blast hole blasts to form a cavity, it creates a free face for the subsequent blast holes. The width of the free face can be determined by the blasting funnel after the first blast hole blasts. Generally, the clamping coefficient is used to represent the clamping effect of the rock, and the clamping coefficient conforms to the formula: In the formula: Z represents the clamping coefficient of the rock, W represents the minimum resistance line of the charge, and B represents the length of the blasting free face; In the case of single free face blasting, the charge amount can be determined by the following formula: Q = q(Z)V In the formula: Q is the charge amount, q(Z) is the specific charge of the explosive, which is a function of the rock clamping coefficient, and V is the volume of the blasted rock; The charging form of the cut hole is columnar charging, as shown in the following formula: From the above formula, it can be seen that when Q' is certain, the optimal resistance line of the blast hole is selected according to the width of the free face to ensure the best effect of cut blasting when the blasting funnel is the largest; The optimal resistance line increases with the increase of the free face within a certain range, that is, the optimal resistance line can be considered as a monotonically increasing function of the free face width, as shown in the formula: When the width of the free face reaches a certain value, the optimal resistance line reaches the maximum, that is: When B < B0, a differential equation can be formed: Where c is a constant, and solving the equation gives the formula: According to experience, c=1.5, B0=0.8, and B is the hole spacing between the first blast hole and the empty hole.

4. The blasting process of the energy-gathering structure coupled cutting device based on bulk explosives according to claim 1 is characterized in that: The method of obtaining lithology by vertical drilling, calculating the matching between rock wave impedance and explosive wave impedance, and determining the explosive content includes: Establish the relationship model between drilling rig speed, rock properties, and drilling rig working parameters: v=F(P,P 风 ,oh,r 材 ,A,p,f,S c ,S t ,S s ) Where: Drilling rig pressure P, wind pressure P 风 , the speed of the drill rig ω, the material of the drill bit ρ 材 , shape and size A, rock density ρ, rock hardness coefficient f, rock compressive strength S c , rock tensile strength S t , rock shear strength S s ; In actual engineering, the material and shape of the drill bit are fixed, and the impact pressure, wind pressure and rotation speed of the drill are set as constants to obtain a simplified model. The drilling speed of the drill only changes with the properties of the rock, that is: v=K·F(ρ,f,s c ,s t ,s s ) The distribution of rock hardness and other properties can be judged from the drilling speed of the drilling rig; the drilling speed can be calculated as follows: Where: v is the drilling speed of the drilling rig; P is the axial pressure; n is the drill bit speed; D is the borehole diameter; f is the rock strength coefficient; From the above drilling speed formula, it can be concluded that as long as the performance index of the drilling rig is fixed and the borehole diameter is fixed, the drilling speed v of the drilling rig can be obtained through field observation, and the Proctor hardness coefficient of the rock can be obtained accordingly. That is to say, the two expressions can be synthesized into a form as follows: v=K·g(f,D) Where K is a constant; Calculate the explosive capacity; the larger the explosion capacity, the more explosive gas products there are and the higher the work efficiency. The formula is as follows: Where V 药 is the explosive capacity of the explosive; ∑n j is the total number of moles of gas detonation products; m i is the number of moles of explosive component i; Me i is the molecular weight of explosive component i; The approximate theoretical equation of detonation fluid dynamics theory is often used in engineering to estimate the detonation velocity of explosives, such as: Where D is the detonation velocity; Q v is the ideal explosion heat; K is the local isentropic index of the detonation product; The ammonium nitrate content in the explosive component is positively correlated with the detonation heat, detonation velocity, and wave impedance of the explosive; as the ammonium nitrate content increases, the detonation velocity, detonation heat, and wave impedance all increase, and vice versa; as the ammonium nitrate content increases, the detonation capacity decreases, and vice versa; The wave impedance of rock P 石 is the density of the rock 石 and the propagation speed of sound waves in the rock mass c 石 constitute; P 石 =ρ 石 ×c 石 ; Calculate the density of the explosive to determine the content of ammonium nitrate, as follows: P 石 =P 药 5. The blasting process of the energy-gathering structure coupled cutting device based on bulk explosives according to claim 1 is characterized in that: The step of processing the energy-gathering structure coupling cutting device in step 4 includes: S1: Use a crystal crusher to crush the mixed ammonium nitrate and sodium nitrate, dissolve the crushed ammonium nitrate in water, and then add a dispersant and stir evenly; S2: After the oil phase solid composite material is melted, the oil phase liquid composite material is injected to homogenize the mixture, and then an emulsifier is added, and the temperature is controlled at 85°C; the emulsifier is a polyisobutylene succinimide emulsifier; S3: the obtained oil phase solution is mixed with the aqueous phase solution, and a stirring process is performed at a speed of 600 r / min for 3 min to obtain colostrum, and then the mixed solution is sent to a static mixer for finishing to obtain latex; S4: putting the obtained latex into a cooler and cooling it to 25° C.; adding a sensitizer to the cooled latex to start sensitization, discharging the material while sensitizing, and then filtering it through a filter to obtain explosives; S5: the emulsion explosive obtained in step S4 is loaded into a charge cylinder, and then squeezed downward by a mechanical push plate. Under the action of squeezing, the emulsion explosive is squeezed from the charge cylinder into the energy-gathering tube, thereby realizing coupled charging.

6. The blasting process of the energy-gathering structure coupled cutting device based on bulk explosives according to claim 1 is characterized in that: The step 5 comprises: An energy-gathering tube connecting device is used to connect the energy-gathering tubes of the energy-gathering structure coupling cutting device. The energy-gathering tubes are provided with V-shaped energy-gathering grooves at both ends that are evenly distributed at a fixed angle along the tube body axis, and the vertex opening directions of all V-shaped energy-gathering grooves point to the center of the tube body; the tube-to-tube connecting device is provided with corresponding V-shaped protrusions for the V-shaped energy-gathering grooves at both ends, and the inner diameter of the connecting device is the same as the outer diameter of the energy-gathering tube to achieve a close connection. When in use, the bottom of the previous energy-gathering tube and the top of the next energy-gathering tube are placed in the tube-to-tube connecting device, and tape is used to wrap the top and bottom of the tube-to-tube connecting device to ensure that the connection is fixed.

7. The blasting process of the energy-gathering structure coupled cutting device based on bulk explosives according to claim 4 is characterized in that: The wave impedance of rock P 石 is the density of the rock 石 and the propagation speed of sound waves in the rock mass c 石 The propagation speed of sound waves in the rock mass is c 石 It can be measured by rock acoustic parameter instrument, the specific steps are as follows: S1: Take the rock specimen to be tested, label it and record the specimen height l; S2: Zero the instrument, place the measuring probes at both ends of the standard sample, and keep the measuring probes on the same horizontal line; S3: Operate the rock acoustic wave detector to record the propagation time t of the elastic wave in the specimen, and calculate and record the rock elastic wave velocity using the following formula: The wave impedance P of explosives 药 is the density of the explosive ρ 药 and the explosive detonation velocity D; P 药 =ρ 药 ×D.

8. The blasting process of the bulk explosive-based energy-gathering structure coupled cutting device according to claim 6 is characterized in that: The obtained latex is placed in a cooler and cooled to 25° C. The cooled latex is added with a sensitizer to start sensitization, and the material is discharged while sensitizing, and then filtered through a filter to obtain explosives including: Using NaNO2 as a foaming agent, phosphoric acid, citric acid, etc. as accelerators for chemical sensitization: Sodium nitrite meets ammonium nitrate in the latex matrix system to generate unstable ammonium nitrite, namely: NH4NO3+NaNO2→NH4NO2+NaNO3 NH4NO2→N2↑+2H2O Emulsion explosives and other water-containing explosives use the above formula to generate microbubbles, and the main gas in the microbubbles is N2; the density of emulsion explosives is adjusted by sensitizers, which is mainly achieved by changing the volume of microbubbles introduced into the explosives. Reasonable consideration of the sensitization temperature and time has a certain effect on promoting bubble generation, and the amount of sensitizer added is reasonably determined to achieve chemical sensitization of emulsion explosives: Sensitizer addition amount According to the reaction mechanism of sodium nitrite, if more N2 tiny bubbles are to be obtained, the dosage of sodium nitrite can be increased. The calculation formula of the dosage of sensitizer is: Where: G m is the dosage of sensitizer; ρ B is the designed density of emulsion explosive; V R V is the volume per kg of latex matrix; G is the gas production of the sensitizer.

9. A bulk explosive-based energy-gathering structure coupled cutting device, comprising a charge cylinder, wherein the charge cylinder is loaded with emulsion explosives, and a V-shaped energy-gathering groove is axially arranged on the charge cylinder, characterized in that: The charge cylinder is loaded with the emulsion explosive produced according to the steps of claim 5.

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