Rock blasting parameter determination method and measuring plate based on acoustic wave velocity, hole depth and explosive load

Abstract

The invention is suitable for the technical field of geotechnical engineering blasting, and provides a rock mass blasting parameter determination method based on sound wave velocity, hole depth and explosive load and a measuring plate, the method comprises the following steps: firstly, through multiple rounds of blasting tests, obtaining a data sample set of a sound wave longitudinal wave velocity Vp before blasting, a hole depth h of a blasting hole, an explosive load Q, a wave velocity loss rate eta and a relaxation depth d; then, on the basis of the data sample set, Vp and h serve as variables, and a visual measuring plate of the explosive load Q is constructed through triangular meshing and isoline tracking; before actual blasting, according to the actually measured Vp before blasting and the designed hole depth h, the optimal explosive loading amount can be rapidly determined by searching the measuring plate. The method solves the problem that in the prior art, the explosive load cannot be directly and accurately determined before blasting, quantitative design and accurate control of blasting parameters are achieved, and the method has the advantages of being efficient, visual, objective and capable of being dynamically optimized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of geotechnical engineering blasting, in particular to a rock mass blasting parameter determination method and a quantity board based on sound wave velocity, hole depth and charge quantity. BACKGROUND

[0002] The core goal of controlling rock mass blasting quality is to achieve uniform broken block size, accurate contour excavation, small post-blasting rock mass damage and controllable safety risk. Currently, the commonly used methods for controlling rock mass blasting quality mainly include experience method, sound wave method and blasting vibration monitoring method.

[0003] The experience method relies on the personal experience of engineers or industry manuals, and determines the blasting parameters through analogy and adjustment, the most classic being the unit volume explosive consumption method. Although this method is simple and efficient, it is greatly affected by the complexity of geological conditions and subjective judgment of engineers, making it difficult to accurately control the charge quantity, leading to overbreak, underbreak or surrounding rock damage, and lacking sustainability and replicability.

[0004] The sound wave method evaluates the surrounding rock damage degree by comparing the change of rock mass sound wave velocity before and after blasting, and then optimizes the blasting parameters. This method provides a quantitative damage index, but it is essentially an indirect evaluation and optimization tool, and cannot directly determine the optimal charge quantity before blasting. When excessive damage is detected, the loss has already occurred.

[0005] The blasting vibration monitoring method evaluates the impact on the surrounding environment by collecting and analyzing blasting vibration signals, and its core value lies in controlling safety risks, but it has weak control ability over other dimensions of blasting quality (such as block size and contour), and it also belongs to post-feedback, and the empirical formula on which it is based is prone to failure under complex geological conditions.

[0006] Therefore, in view of the above status, it is urgent to provide a rock mass blasting parameter determination method and a quantity board based on sound wave velocity, hole depth and charge quantity to overcome the shortcomings in current practical applications. SUMMARY

[0007] The purpose of the present application is to provide a rock mass blasting parameter determination method and a quantity board based on sound wave velocity, hole depth and charge quantity, which effectively solve the problems in the background art.

[0008] The present application is implemented as follows: a rock mass blasting parameter determination method based on sound wave velocity, hole depth and charge quantity, which comprises the following steps:

[0009] Through multiple rounds of blasting tests, data samples containing pre-blast sound wave longitudinal wave velocity V p , blasting hole depth h, blasting hole explosive charge quantity Q, sound wave velocity loss rate η and rock mass relaxation depth d are obtained to form a data sample set;

[0010] The pre-blast sound wave longitudinal wave velocity Vp and the blast hole depth h is the independent variable, and the blast hole explosive charge Q is the dependent variable, a two-dimensional coordinate system is established, triangular meshing and contour tracing are carried out based on the data sample set, the contour of the charge Q is drawn, and a visual scale is formed;

[0011] Based on the pre-blast acoustic wave velocity V p当前 and the designed blast hole depth h 设计 , the corresponding optimal blast hole explosive charge Q 最佳 is determined by searching on the scale.

[0012] As a further scheme of the present application: the pre-blast acoustic wave velocity V p and the post-blast acoustic wave velocity used to calculate η and d are both measured by the single-hole acoustic wave method.

[0013] As a further scheme of the present application: the specific steps for measuring the acoustic wave velocity by the single-hole acoustic wave method are as follows:

[0014] A single-hole acoustic wave probe is used, the transmitting transducer radiates acoustic waves, when the acoustic wave incidence angle is equal to the first critical angle, the acoustic waves are refracted along the hole wall and then refracted back into the hole, and the received by the receiving transducer 1 and the receiving transducer 2, respectively, and then the propagation velocity of the acoustic waves in the rock mass between the two receiving transducers is calculated by using the distance between the two receiving transducers and the first arrival time difference of the refracted waves.

[0015] As a further scheme of the present application: the calculation formula of the acoustic wave velocity V p is as follows:

[0016]

[0017] Wherein, L is the distance between the two receiving transducers, and Δt is the travel time difference of the acoustic wave between the two receiving transducers.

[0018] As a further scheme of the present application: the calculation formula of the acoustic wave velocity damage rate η is as follows:

[0019]

[0020] Wherein, is the wave velocity before explosion, is the wave velocity after explosion.

[0021] As a further scheme of the present application: the method further comprises:

[0022] With the acquisition of new blasting data samples, the data sample set is updated, and the scale is dynamically corrected.

[0023] As a further scheme of the present application: Q is determined by positioning coordinate points on the chart and determining Q by interpolation of the contour lines or adjacent contour lines at the positions of the coordinate points 最佳 .

[0024] The present application also provides a rock mass blasting parameter determination chart based on acoustic wave velocity, hole depth and charge quantity, which is constructed by the above method.

[0025] The chart is a visual chart, taking the pre-blast acoustic wave longitudinal wave velocity V p as the first coordinate axis, taking the blasting hole depth h as the second coordinate axis, and drawing contour lines representing different blasting hole charge quantities Q on the chart.

[0026] As a further scheme of the present application: the chart is provided with exclusive categories corresponding to rock masses of different lithology, and the lithology category can be quickly switched and adapted according to the change of rock mass mechanical parameters.

[0027] As a further scheme of the present application: the chart can be iteratively corrected by newly added pre-blast and post-blast acoustic wave test data to optimize the correspondence accuracy between V p , h and Q.

[0028] Compared with the prior art, the present application has the following beneficial effects:

[0029] Precise matching of rock mass characteristics reduces the damage to surrounding rock and ensures the long-term stability of dam foundation and underground cavern.

[0030] Simplifies the parameter design process, and after the chart is established, post-blast hole detection does not need to be added for a long time, and on-site detection only takes 30 minutes, which improves the construction efficiency and adapts to the rhythm of dam foundation and underground cavern.

[0031] The chart method can effectively know the blasting work, control the blasting quality, strictly control the excavation contour and overbreak or underbreak, reduce the subsequent treatment cost, and ensure the construction quality of the structure.

[0032] High-quality blasting work can effectively control the flying stones and vibration caused by blasting, reduce the harm to nearby construction personnel, equipment and adjacent buildings, and reduce the blasting safety risk.

[0033] Optimizing resource allocation, reducing comprehensive cost, and achieving "quality-cost" balance. This is because the cost of blasting mainly comes from explosive consumption, drilling cost, overbreak or underbreak treatment cost, and the chart realizes multi-dimensional cost saving through parameter optimization.

[0034] The chart is not a "one-time tool", but a closed-loop management embedded with "pre-blast design-post-blast verification-parameter correction". BRIEF DESCRIPTION OF DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the specific embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the specific embodiments or the prior art description. Obviously, the drawings described below are some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0036] Figure 1 The gauge plate example of the present application. DETAILED DESCRIPTION

[0037] The technical solutions of the present application will be described clearly and completely in the following with reference to the drawings. Obviously, the described embodiments are some embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the present application.

[0038] The present application will be further explained and described in the following with reference to specific embodiments.

[0039] Please refer to Figure 1 The rock mass blasting parameter determination method based on sound wave velocity, hole depth and explosive charge provided by the embodiments of the present application comprises the following steps:

[0040] Through multiple rounds of blasting tests, data samples containing pre-blast sound wave longitudinal wave velocity V p , blasting hole depth h, blasting hole explosive charge Q, sound wave velocity loss rate η and rock mass relaxation depth d are obtained to form a data sample set;

[0041] Taking the pre-blast sound wave longitudinal wave velocity V p and the blasting hole depth h as independent variables, and taking the blasting hole explosive charge Q as dependent variable, a two-dimensional coordinate system is established, triangular meshing and contour tracing are carried out based on the data sample set, the contour line of the charge Q is drawn, and a visual gauge plate is formed;

[0042] Based on the pre-blast sound wave longitudinal wave velocity V p当前 and the designed blasting hole depth h 设计 obtained by testing the current area to be blasted, the corresponding optimal blasting hole explosive charge Q 最佳 is determined by searching on the gauge plate.

[0043] The pre-blast sound wave longitudinal wave velocity V p and the post-blast sound wave longitudinal wave velocity used for calculating η and d are both measured by single-hole sound wave method.

[0044] The method further comprises:

[0045] With the new blast data samples obtained, update the data sample set, dynamically correct the prover.

[0046] By positioning the coordinate points on the prover and determining Q by the contour line at their position or by interpolation of adjacent contour lines 最佳 .

[0047] In this embodiment, the single-hole acoustic wave method for hole measurement is based on the principle of acoustic wave refraction, uses a transmitting and receiving acoustic wave probe, the transmitting transducer radiates acoustic waves, when the acoustic wave incidence angle is equal to the first critical angle, the acoustic wave of the rock mass hole wall is refracted and slides along the hole wall, and then is refracted back into the hole by the receiving transducer 1 and the receiving transducer 2 respectively, and then the propagation velocity of the acoustic wave in the rock mass between the two receiving transducers is calculated by using the distance between the two receiving transducers and the first arrival time difference of the acoustic wave.

[0048] The travel time of the acoustic wave in the rock mass between the two receiving transducers is read from the original data obtained from the field measurement, the acoustic wave longitudinal wave velocity of the rock mass between the two receiving transducers is calculated by the following formula.

[0049]

[0050] In the formula: V p is the acoustic wave longitudinal wave velocity of the medium between the two receiving transducers, (m / s).

[0051] L is the distance between the two receiving transducers, (m).

[0052] Δt is the travel time difference of the acoustic wave longitudinal wave between the two receiving transducers, (s).

[0053] The acoustic time curve is drawn by the V p value, and the velocity division of the pre-blast rock mass and the construction surface rock mass before blasting is carried out, the loose rock mass thickness and the loss rate of the construction surface rock mass after blasting are calculated and compared, and then the technical system of dynamically adjusting the explosive quantity is dynamically adjusted. The traditional method usually considers that the acoustic wave velocity of the rock mass elastic parameter and the hole depth and the explosive quantity are linearly related, but in fact the acoustic wave velocity of the rock mass elastic parameter and the hole depth and the explosive quantity are not a relatively direct linear relationship, therefore, the inversion model of the explosive quantity must be further introduced to realize the final solution purpose of precise blasting.

[0054] The quantity plate method is a method for calculating the explosive charge quantity of a blasting hole by using a numerical model of a data sample set established according to the thickness d of a relaxation circle and the acoustic wave velocity damage rate η obtained by a plurality of pre-blast / post-blast acoustic wave methods and a plane rectangular coordinate system, triangulating and contour tracing the data sample set to obtain the numerical model, and using the numerical model to calculate the explosive charge quantity of the blasting hole in different lithologies at the same site. The quantity plate method is a method based on two-dimensional field theory, which is a two-dimensional field parameter contour map. A two-dimensional function corresponds to a two-dimensional field, and the connecting line of points with the same physical quantity Q=Q(m,n)=R in the two-dimensional field is called the contour line of the physical field. A set of R1, R2,..., Rn contour lines can be drawn in the two-dimensional field.

[0055] If the acoustic wave velocity V p of the rock mass, the hole depth h(φ) parameter of the blasting hole and the explosive charge quantity Q of the blasting hole are combined, three function expressions can be written as follows:

[0056] Q=Q(V p ,h)

[0057] The method establishes the relationship between the pre-blast acoustic wave velocity V p of the rock mass and the explosive charge quantity Q of the blasting hole by comparative tests of the thickness d of the relaxation circle, the acoustic wave velocity damage rate η, the hole depth h(φ) of the blasting hole and the explosive charge quantity Q of the blasting hole, obtains the correlation of the parameters, and then gradually expands and corrects the digital contour line to overcome the linear relationship between the parameters in the traditional method and realize the corresponding relationship of the face-to-face relationship. The schematic diagram is shown in Figure 1 .

[0058] The present application adjusts the best V p -h-Q contour line by the comparison of the pre-blast / post-blast acoustic wave velocity attenuation and the relaxation depth, the dynamic blasting hole depth and the explosive quantity, forms a quantity plate, and the subsequent blasting work obtains the best explosive quantity by the pre-blast hole acoustic wave velocity and the hole depth through the quantity plate to guide the blasting work.

[0059] Different lithologies are made into targeted quantity plates, and when the lithology changes cause the mechanical parameters of the rock mass to change greatly, the quantity plate can quickly switch the rock mass category to achieve accurate control.

[0060] The present application also provides a rock mass blasting parameter determination quantity plate based on acoustic wave velocity, hole depth and explosive charge quantity, and the quantity plate is constructed by the above method.

[0061] The quantity plate is a visual chart, which takes the pre-blast acoustic wave longitudinal wave velocity V p as the first coordinate axis, takes the hole depth h of the blasting hole as the second coordinate axis, and draws the contour line representing different explosive charge quantities Q of the blasting hole on the chart.

[0062] The template board is provided with exclusive categories for rock bodies of different lithology, and the adaptive lithology category can be quickly switched according to the change of the rock body mechanical parameter.

[0063] The template board can be iteratively corrected by the newly added pre-blast-post-blast acoustic wave method test data, so as to optimize the corresponding relationship accuracy between V p , h and Q.

[0064] In the embodiment, the application is simple and easy to operate, and only needs to carry out pre-blast-post-blast acoustic wave velocity and relaxation depth comparison in the early stage of blasting work, and the best V p -h-Q isobars are obtained through dynamic adjustment.

[0065] The field test condition is simple, and only needs to deepen the charging hole by 1-2 m, and the test can be completed within 30 min, and has little influence on the construction progress.

[0066] The use steps of the template board method are highly fixed, the interference of human subjective factors is reduced, and the consistency and reliability of the calculation result can be effectively improved.

[0067] The pre-blast rock acoustic wave velocity can be read on site, the blasting explosive quantity can be quantitatively determined on site through the template board, and real-time accurate guidance of the blasting work can be achieved.

[0068] The template board method converts abstract mathematical operations (such as integral, differential equation and special function solution) into intuitive graphical measurement operations, completely avoids complicated formula derivation and manual calculation, and greatly reduces the requirement for the mathematical and professional technical foundation of the user.

[0069] In the later stage, the sample data can also be gradually corrected, dynamic adjustment is realized, the template board accuracy is improved, and the closed-loop management of 'pre-blast design-post-blast verification-parameter correction' is achieved.

[0070] In summary, the key innovation points of the application are as follows:

[0071] (1) Multi-parameter correlation

[0072] Key point: carry out pre-blast-post-blast acoustic wave velocity attenuation and relaxation depth comparison, obtain the best V p -h-Q isobars through dynamic adjustment, and form a template board.

[0073] (2) Significantly simplify the calculation process and reduce the technical threshold

[0074] Key point: convert abstract mathematical operations (such as integral, differential equation and special function solution) into intuitive graphical measurement operations, and completely avoid complicated formula derivation and manual calculation.

[0075] (3) Quantitative technology of explosive charge in blast hole

[0076] Key point: By testing the pre-blast rock mass acoustic wave velocity and hole depth, the optimal explosive charge can be found by using the gauge.

[0077] (4) Different lithology to make targeted gauge

[0078] Key point: When the lithology changes cause the mechanical parameters of rock mass to change greatly, the gauge can quickly switch the rock mass category and achieve precise control.

[0079] In addition, the following is an explanation of the single-hole acoustic wave method, loss rate η, relaxation depth d, and gauge method:

[0080] Single-hole acoustic wave method: Based on the principle of acoustic wave refraction, the wave velocity of the rock mass is tested.

[0081] Loss rate η: refers to the attenuation of the propagation speed of sound in the medium after the explosion relative to the pre-explosion, which directly reflects the degree of damage to the physical structure of the medium by the explosion. Its calculation formula is:

[0082]

[0083] Where, is the pre-explosion wave velocity, is the post-explosion wave velocity.

[0084] ③ Relaxation depth d: The relaxation depth of the rock mass is the depth of the region where the mechanical properties of the rock mass are significantly degraded due to stress release, micro-crack propagation, and structural damage after the explosion. It is usually determined by the single-hole acoustic wave method.

[0085] ④ Gauge method: A practical calculation method based on the principle of graphical analysis, the core is to quickly solve complex engineering or physical problems by pre-drawing "standard charts (gauge)" containing specific mathematical relationships or physical laws, avoiding repeated formula derivation and tedious calculations. Its essence is to "convert abstract mathematical models into visual graphics", allowing users to directly obtain calculation results through simple operations such as "table lookup, testing, and superposition", which is especially suitable for scenes that need to be determined on site, such as field engineering and geological exploration.

[0086] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and are not limited thereto; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent substitutions for part or all of the technical features; and these modifications or substitutions do not make the essence of the corresponding technical solution deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for determining rock blasting parameters based on acoustic wave velocity, hole depth, and charge quantity, characterized in that, The method includes the following steps: Through multiple rounds of blasting tests, the longitudinal wave velocity V of the pre-blast acoustic wave was obtained. p The data sample set consists of data samples of blast hole depth h, explosive charge Q, sonic velocity loss rate η, and rock mass relaxation depth d; The longitudinal wave velocity V of the pre-detonation acoustic wave p With the blast hole depth h as the independent variable and the explosive charge Q as the dependent variable, a two-dimensional coordinate system is established. Based on the data sample set, triangulation and contour line tracing are performed to draw contour lines of the charge Q, forming a visual measurement plate. Based on the pre-blast acoustic longitudinal wave velocity V obtained from the current test in the area to be blasted. p当前 and the design of the blast hole depth h 设计 The optimal explosive charge Q for the blast hole is determined by searching the measuring plate. 最佳 .

2. The method according to claim 1, characterized in that, The longitudinal wave velocity V of the pre-detonation acoustic wave p The longitudinal wave velocities of the acoustic waves used to calculate η and d after the explosion were both measured by the single-hole acoustic method.

3. The method according to claim 2, characterized in that, The specific steps for measuring the longitudinal wave velocity of acoustic waves using the single-aperture acoustic method are as follows: Using a dual-receiver acoustic probe, the transmitting transducer radiates acoustic waves. When the incident angle of the acoustic wave is equal to the first critical angle, the acoustic wave is refracted along the borehole wall and slides along the borehole wall. Then, it is refracted back into the borehole and received by receiving transducers 1 and 2 respectively. The propagation speed of the acoustic wave in the rock mass between the two receiving transducers is then calculated using the distance between the two receiving transducers and the time difference of the first arrival of the refracted acoustic wave.

4. The method according to claim 2, characterized in that, The longitudinal wave velocity V of the sound wave p The calculation formula is: Where L is the distance between the two receiving transducers, and Δt is the travel time difference of the longitudinal wave of the sound wave between the two receiving transducers.

5. The method according to claim 1, characterized in that, The formula for calculating the acoustic velocity damage rate η is as follows: in, The wave velocity before the explosion. The velocity of the wave after the explosion.

6. The method according to claim 1, characterized in that, The method further includes: As new blasting data samples are obtained, the data sample set is updated, and the measuring plate is dynamically corrected.

7. The method according to claim 1, characterized in that, Q is determined by locating coordinate points on the measuring plate and then using contour lines at those locations or by interpolation through adjacent contour lines. 最佳 .

8. A parameter determination tool for rock blasting based on acoustic wave velocity, hole depth, and charge quantity, characterized in that, The measuring plate is constructed by the method described in any one of claims 1 to 7; The measuring plate is a visual chart that uses the longitudinal wave velocity V of the pre-explosion acoustic wave. p The first coordinate axis is denoted by h, the second coordinate axis is denoted by the hole depth h, and contour lines representing the explosive charge Q of different blast holes are plotted on the chart.

9. The measuring plate according to claim 8, characterized in that, The measuring plate has a dedicated category for rock masses with different lithologies, and the appropriate lithology category can be quickly switched according to changes in the rock mass mechanical parameters.

10. The measuring plate according to claim 8, characterized in that, The measurement plate can be iteratively corrected using newly added pre- and post-explosion acoustic wave test data to optimize V. p The accuracy of the correspondence between h and Q.

Images