Blasting safety prediction method and system for tunneling blasting by using energy-gathered pipe cover

Abstract

The invention relates to the technical field of blasting monitoring, in particular to a blasting safety prediction method and system for tunneling blasting through an energy-gathered pipe cover, and the method comprises the following steps: when the energy-gathered pipe cover is used for energy-gathered smooth blasting, based on a dimensional analysis method, improving a Sadgowski formula in consideration of a terrain effect, obtaining a first blasting vibration speed prediction model; obtaining a second blasting vibration speed prediction model based on a dimensional analysis method and the first blasting vibration speed prediction model by considering the destructive effect of blasting on the surrounding rock structure; and predicting the blasting vibration speed of the blasting point by using a second blasting vibration speed prediction model, further judging the safety of the environment where the blasting point is located, and predicting the safety of the ground building according to a prediction result. The blasting vibration speed prediction accuracy and efficiency can be improved during energy-gathered smooth blasting, the blasting safety prediction accuracy and efficiency are further improved, and the engineering cost and the safety risk are reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of blasting monitoring, and in particular, to a blasting safety prediction method and system for tunneling blasting using a shaped charge tube. Background Art

[0002] In underground engineering such as tunnels and mines, blasting is a commonly used construction method. As an efficient blasting tool, the shaped charge tube can significantly improve the blasting effect and tunneling efficiency by focusing the explosion energy for shaped charge smooth blasting. However, due to the concentration of the energy distribution of shaped charge smooth blasting, the vibration velocity generated by blasting may be more significant. Moreover, with the expansion of the project scale and the increase in the complexity of the surrounding environment, shaped charge smooth blasting will still have a greater impact on ground buildings, underground pipelines, etc. Therefore, when using a shaped charge tube for tunneling blasting, how to accurately predict the blasting vibration velocity and then accurately predict the blasting safety, including predicting the safety of the environment where the blasting point is located and the safety of ground buildings during the blasting process, has become an urgent problem to be solved in the current engineering field.

[0003] Currently, the most widely used formula in the field of blasting vibration research is the Sadovskii formula. However, with the increase in the complexity of the blasting environment and the continuous in-depth study of blasting vibration, the Sadovskii formula is no longer accurate. In order to improve the accuracy of predicting the blasting vibration velocity, researchers have considered improving the Sadovskii formula or using machine learning algorithms to improve the accuracy of predicting the blasting vibration velocity.

[0004] However, most of the currently improved Sadovskii formulas only further consider the free face area or the elevation of the vibration monitoring point and the blasting point, ignoring the damage effect of blasting on the surrounding rock structure, thereby reducing the accuracy of predicting the blasting vibration velocity and further reducing the accuracy of blasting safety prediction during multi-hole delay blasting. In addition, due to the uneven quality of explosion data, it is difficult to ensure the stability of the blasting vibration velocity based on machine learning algorithms. Moreover, in order to improve the prediction accuracy, the prediction model is often designed to be very complex and inevitably requires a sufficient number of blasting simulation experiments or field experiments to verify and optimize the model, which not only takes time and effort, reduces the efficiency of blasting safety prediction, but also may increase the project cost and safety risks. Summary of the Invention

[0005] Aiming at the deficiencies in the prior art, the present invention provides a blasting safety prediction method and system for tunneling blasting using a shaped charge tube.

[0006] To achieve the above object, in a first aspect, the present invention provides a blasting safety prediction method for tunneling blasting using a shaped charge tube cover. The method includes the following steps: When performing shaped charge smooth blasting using a shaped charge tube cover, based on the dimensional analysis method, considering the terrain effect to improve the Sadovsky formula, and then obtaining a first blasting vibration velocity prediction model; Considering the damage effect of blasting on the surrounding rock structure, obtaining a second blasting vibration velocity prediction model based on the dimensional analysis method and the first blasting vibration velocity prediction model; Using the second blasting vibration velocity prediction model to predict the blasting vibration velocity at the blasting point, and then judging the safety of the environment where the blasting point is located; Predicting the safety of ground buildings according to the prediction result of the blasting vibration velocity at the blasting point by the second blasting vibration velocity prediction model. The present invention can improve the accuracy and efficiency of predicting the blasting vibration velocity during shaped charge smooth blasting, thereby improving the accuracy and efficiency of blasting safety prediction, reducing engineering costs and safety risks.

[0007] Optionally, when performing shaped charge smooth blasting using a shaped charge tube cover, based on the dimensional analysis method, considering the terrain effect to improve the Sadovsky formula, and then obtaining the first blasting vibration velocity prediction model includes the following steps: Under the condition of considering the terrain effect, determine the basic dimensions for the first blasting vibration dimensional analysis and the physical quantities involved in the vibration wave propagation process during tunneling blasting using a shaped charge tube cover; Conduct the first blasting vibration dimensional analysis according to Buckingham's theorem to obtain the first set of dimensionless variables represented by π; Based on the first set of dimensionless variables, only consider the relationship between the maximum single-section charge amount, the distance from the blast center, the elevation difference, and the ground field coefficient, and consider the attenuation relationship between the ratio of the elevation difference to the distance from the blast center and the blasting vibration velocity to obtain a first relational expression; Substitute the Sadovsky formula into the first relational expression and simplify it to obtain the first blasting vibration velocity prediction model.

[0008] Optionally, the first relational expression satisfies the following relationship: Wherein, is the blasting vibration velocity, is the site coefficient of the blasting point, is the terrain influence coefficient, is the attenuation coefficient, R is the distance from the blast center, Q is the maximum single-section charge amount, is the elevation influence coefficient, is the elevation difference between the blasting point and the vibration monitoring point.

[0009] Optionally, the first blasting vibration velocity prediction model satisfies the following relationship: Among them, is the blasting vibration velocity, is the site coefficient of the blasting point, is the terrain influence coefficient, is the attenuation coefficient, R is the distance from the blast center, and Q is the maximum charge per delay, is the elevation influence coefficient, is the elevation difference between the blasting point and the vibration monitoring point.

[0010] Optionally, considering the destructive effect of blasting on the surrounding rock structure, obtaining the second blasting vibration velocity prediction model based on the dimensional analysis method and the first blasting vibration velocity prediction model includes the following steps: Considering the destructive effect of blasting on the surrounding rock structure, introducing the effective influence radius of shaped charge smooth blasting and the change ratio of the elastic modulus of the surrounding rock, and then conducting the second dimensional analysis of blasting vibration; Conduct the second dimensional analysis of blasting vibration according to Buckingham's theorem to obtain the second set of dimensionless variables expressed by π; Based on the second set of dimensionless variables, considering only the relationship between the maximum charge per delay, the distance from the blast center, the elevation difference, the effective influence radius, the change ratio of the elastic modulus of the surrounding rock, and the site coefficient, obtain the second relational expression; Obtain the second blasting vibration velocity prediction model according to the first blasting vibration velocity prediction model and the second relational expression.

[0011] Optionally, the second relational expression satisfies the following relationship: Among them, is the blasting vibration velocity, is the site coefficient of the blasting point, is the terrain influence coefficient, is the destructive influence coefficient of shaped charge smooth blasting on the surrounding rock, r is the effective influence radius of shaped charge smooth blasting, is the change ratio of the elastic modulus of the surrounding rock, is the attenuation coefficient, R is the distance from the blast center, and Q is the maximum charge per delay, is the elevation influence coefficient, is the influence coefficient related to the change ratio of the elastic modulus of the surrounding rock, is the elevation difference between the blasting point and the vibration monitoring point.

[0012] Optionally, the second blasting vibration velocity prediction model satisfies the following relationship: Among them, is the blasting vibration velocity, is the site coefficient for the blasting point, is the terrain influence coefficient, is the damage influence coefficient of shaped charge smooth blasting on surrounding rock, r is the effective influence radius of shaped charge smooth blasting, is the change ratio of the elastic modulus of the surrounding rock, is the attenuation coefficient, R is the distance from the blast center, Q is the maximum charge per delay, is the elevation influence coefficient, is the influence coefficient related to the change ratio of the elastic modulus of the surrounding rock, is the elevation difference between the blasting point and the vibration monitoring point.

[0013] Optionally, predicting the blasting vibration velocity at the blasting point using the second blasting vibration velocity prediction model, and then judging the safety of the environment where the blasting point is located includes the following steps: Predict the blasting vibration velocity at the vibration monitoring point using the second blasting vibration velocity prediction model, and record the prediction result as the predicted vibration velocity value; Compare the predicted vibration velocity value with the maximum allowable blasting vibration velocity of the environment where the blasting point is located, and then judge the safety of the environment where the blasting point is located.

[0014] Optionally, predicting the safety of the ground building according to the prediction result of the blasting vibration velocity at the blasting point using the second blasting vibration velocity prediction model includes the following steps: Construct an evaluation model for evaluating the safety of the ground building when tunneling blasting is carried out using a shaped charge pipe shield. The evaluation model satisfies the following relationship: Wherein, is the numerical value of the safety index, n is the number of blast holes, is the predicted vibration velocity value caused by the blasting of the i-th blast hole, is the maximum allowable vibration velocity of the ground building, is the independent variable, is the standard deviation of the blasting vibration velocity; Substitute the predicted vibration velocity value into the evaluation model, and then calculate the numerical value of the safety index.

[0015] In a second aspect, the present invention provides a blasting safety prediction system for tunneling blasting using a shaped charge pipe shroud. The blasting safety prediction system for tunneling blasting using a shaped charge pipe shroud includes: a data acquisition device, a data output device, a processor, and a storage. The storage includes a computer-readable storage medium, and a computer program is stored in the computer-readable storage medium. The computer program includes program instructions, and when the program instructions are executed by the processor, the processor implements the blasting safety prediction method for tunneling blasting using a shaped charge pipe shroud provided by the present invention. This system can stably run this method, which can not only improve the efficiency of blasting safety prediction but also improve the practicability of this method.

[0016] In summary, the present invention has at least the following beneficial effects: 1. Compared with the existing Sadovsky formula and its improved formulas, this method first obtains the first blasting vibration velocity prediction model by introducing the elevation difference between the vibration monitoring point and the blasting point into the Sadovsky formula, and then further introduces the effective influence radius of shaped charge smooth blasting and the change ratio of the elastic modulus of the surrounding rock on the basis of the first blasting vibration velocity prediction model, thereby considering the damage effect of shaped charge smooth blasting on the surrounding rock, improving the accuracy of the prediction of blasting vibration velocity, and further improving the accuracy of blasting safety prediction.

[0017] 2. Compared with the blasting vibration velocity prediction method based on machine learning algorithms, this method does not require a large number of blasting experiments to optimize the model after determining the second blasting vibration velocity prediction model, improving the efficiency of blasting safety prediction and being beneficial to reducing engineering costs and safety risks.

[0018] 3. This method constructs an evaluation model for evaluating the safety of ground buildings, which can quantify the safety degree of ground buildings during shaped charge smooth blasting, thereby more intuitively reflecting the safety of ground buildings during shaped charge smooth blasting, and can improve the accuracy of blasting safety prediction during shaped charge smooth blasting.

[0019] 4. The system provided by the present invention not only has the advantages of the method provided by the present invention but also can improve the efficiency of blasting safety prediction and the practicability of this method. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present application and should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0021] Figure 1Schematic flowchart of a blasting safety prediction method using a shaped charge tube shield for tunneling blasting according to an embodiment of the present invention; Figure 2 Schematic framework diagram of a blasting safety prediction system using a shaped charge tube shield for tunneling blasting according to an embodiment of the present invention. Detailed implementation manners

[0022] The specific embodiments of the present invention will be described in detail below. It should be noted that the embodiments described here are only for illustrative purposes and are not used to limit the present invention. In the following description, a large number of specific details are set forth in order to provide a thorough understanding of the present invention. However, it is obvious to those of ordinary skill in the art that the present invention does not have to employ these specific details. In other instances, well-known circuits, software, or methods have not been specifically described in order to avoid obscuring the present invention.

[0023] Throughout the specification, the mention of "one embodiment", "an embodiment", "one example" or "an example" means that a particular feature, structure, or characteristic described in connection with the embodiment or example is included in at least one embodiment of the present invention. Thus, the phrases "in one embodiment", "in an embodiment", "one example" or "an example" appearing throughout the specification do not necessarily all refer to the same embodiment or example. In addition, the specific features, structures, or characteristics may be combined in any suitable combination and / or sub-combination in one or more embodiments or examples. Moreover, those of ordinary skill in the art should understand that the diagrams provided herein are for illustrative purposes only and are not necessarily drawn to scale.

[0024] It should be noted in advance that in an optional embodiment, unless otherwise independently stated, the same symbols or letters appearing in all formulas represent the same meanings and values.

[0025] In an optional embodiment, please refer to Figure 1 , the present invention provides a blasting safety prediction method using a shaped charge tube shield for tunneling blasting, and the method includes the following steps: S1. When using a shaped charge tube shield for shaped charge smooth blasting, based on the dimensional analysis method, the Sadovsky formula is improved considering the terrain effect, and then the first blasting vibration velocity prediction model is obtained.

[0026] Among them, step S1 specifically includes the following steps: S11. Considering the terrain effect, determine the basic dimensions for the first blasting vibration dimensional analysis and the physical quantities involved in the vibration wave propagation process when using a shaped charge tube shield for tunneling blasting.

[0027] Specifically, in this embodiment, the energy-gathering pipe hood refers to combining an energy-gathering pipe with an energy-gathering hood to form a pipe hood, which is directly used in combination with explosives to make energy-gathering explosives, enabling the explosives to produce an energy-gathering effect and cut rocks during explosion, thereby achieving the purpose of energy-gathering smooth blasting. At the same time, it can also replace the detonating cord to achieve in-hole interval detonation transfer. Compared with the current conventional smooth blasting, using the energy-gathering pipe hood for energy-gathering smooth blasting has at least the following advantages: enlarging the smooth blasting hole spacing to 60 - 100 cm, reducing 1 / 3 to 1 / 2 of the perimeter holes, and shortening the drilling operation time; reducing the disturbance to the surrounding rock and maintaining the stability of the surrounding rock; having a good smooth blasting effect, reducing overbreak, and reducing the amount of concrete used; fewer holes can save digital detonators, and the lower-cost energy-gathering hood replaces the detonating cord, thus reducing costs. However, since using the energy-gathering pipe hood will enable the explosives to produce an energy-gathering effect, the vibration velocity generated by the blasting may be more significant. Therefore, accurately predicting the blasting vibration velocity and then accurately evaluating the blasting safety is particularly important.

[0028] More specifically, the basic dimensions include mass M, time T, and distance L. The physical quantities include the vibration velocity of the vibration monitoring point, the maximum single-section charge amount, the distance from the blast center, the elevation difference between the blasting point and the vibration monitoring point, the vibration wave propagation velocity, the rock mass density, the blasting duration, as well as the vibration displacement, vibration frequency, and vibration acceleration of the vibration monitoring point, and their corresponding dimensions are shown in Table 1.

[0029] Table 1 Comparison table of physical quantities and dimensions Furthermore, the vibration velocity of the vibration monitoring point is simultaneously affected by the other 9 physical quantities. In other alternative embodiments, other physical quantities may also be included.

[0030] S12. Conduct the first blasting vibration dimension analysis according to Buckingham's theorem to obtain a plurality of first groups of dimensionless variables represented by π.

[0031] Specifically, in this embodiment, taking the maximum single-section charge amount, the distance from the blast center, and the vibration wave propagation velocity as independent dimensions, then according to Buckingham's theorem, there will be 7 dimensionless variables. In the order of the physical quantities in Table 1, the other 7 physical quantities except the maximum single-section charge amount, the distance from the blast center, and the vibration wave propagation velocity are successively represented by π as the first group of dimensionless variables. The first group of dimensionless variables includes 、 、 、 、 、 and , as specifically shown in Table 2.

[0032] Table 2 Physical quantities and their corresponding dimensionless variables S13. Based on the first set of dimensionless variables, only consider the relationships among the maximum single-section charge amount, the distance from the explosion center, the elevation difference, and the ground field coefficient, and consider the attenuation relationship between the ratio of the elevation difference to the distance from the explosion center and the blasting vibration velocity, to obtain the first relational expression.

[0033] Specifically, in this embodiment, for the same blasting area, regard the vibration wave propagation velocity and the rock mass density as constants, only consider the relationships among the maximum single-section charge amount, the distance from the explosion center, the elevation difference, and the ground field coefficient, and consider the attenuation relationship between the ratio of the elevation difference to the distance from the explosion center and the blasting vibration velocity, that is , denotes the functional relational expression with respect to and , and then obtain the first relational expression. The first relational expression specifically satisfies the following relationship: wherein, is the blasting vibration velocity, is the site coefficient of the blasting point, is the terrain influence coefficient, is the attenuation coefficient, R is the distance from the explosion center, Q is the maximum single-section charge amount, is the elevation influence coefficient, is the elevation difference between the blasting point and the vibration monitoring point.

[0034] S14. Substitute the Sadovsky formula into the first relational expression and simplify it to obtain the first blasting vibration velocity prediction model.

[0035] Specifically, in this embodiment, the logarithmic form of the Sadovsky formula is , substitute it into the first relational expression and simplify it, to obtain that the first blasting vibration velocity prediction model satisfies the following relationship: Furthermore, the first blasting vibration velocity prediction model further considers the influence of the elevation difference between the blasting point and the vibration monitoring point on the vibration velocity on the basis of the Sadovsky formula, improves the accuracy of predicting the blasting vibration velocity to a certain extent, and further improves the accuracy of predicting the blasting safety.

[0036] S2. Consider the damage effect of blasting on the surrounding rock structure, and obtain the second blasting vibration velocity prediction model based on the dimensional analysis method and the first blasting vibration velocity prediction model.

[0037] Among them, step S2 specifically includes the following steps: S21. Consider the damage effect of blasting on the surrounding rock structure, introduce the effective influence radius of shaped charge smooth blasting and the change ratio of the elastic modulus of the surrounding rock, and then conduct the second blasting vibration dimensional analysis.

[0038] Specifically, in this embodiment, when using the energy-gathering pipe shield for tunneling blasting, the blasting will damage the surrounding rock structure and affect the blasting vibration velocity, thereby affecting the accuracy of predicting the blasting vibration velocity at the vibration monitoring point. In order to further improve the accuracy of predicting the blasting vibration velocity at the vibration monitoring point and further improve the accuracy of predicting the blasting safety, this embodiment further considers the effective influence radius of the shaped charge smooth blasting and the change ratio of the elastic modulus of the surrounding rock on the basis of the physical quantities in Table 1. Among them, the change ratio of the elastic modulus of the surrounding rock is the ratio of the change in the elastic modulus of the surrounding rock before and after blasting to the initial value of the elastic modulus of the surrounding rock; the blasting will cause cracks in the surrounding rock, and the effective influence radius of the shaped charge smooth blasting is the radius of the circular area where the cracks are located. The effective influence radius of the shaped charge smooth blasting can be estimated using the following relational expression, that is: where r is the effective influence radius of the shaped charge smooth blasting, is the transverse strain of the surrounding rock where the blasting point is located, is the longitudinal strain of the surrounding rock where the blasting point is located, is the longitudinal wave velocity of the surrounding rock, is the explosive density, is the propagation velocity of the detonation wave in the explosive column when the explosive in the energy-gathering pipe shield explodes, is the adiabatic index, is the hole radius, is the tensile strength of the surrounding rock. The parameters used for calculating the effective influence radius of the shaped charge smooth blasting can all be obtained by existing technical means, and will not be elaborated here.

[0039] S22. Conduct the second blasting vibration dimensional analysis according to Buckingham's theorem to obtain the second group of dimensionless variables expressed by π.

[0040] Specifically, in this embodiment, the second group of dimensionless variables includes the first group of dimensionless variables, and also includes the effective influence radius r of the shaped charge smooth blasting and the two dimensionless variables corresponding to the change ratio of the elastic modulus of the surrounding rock and .

[0041] S23. Based on the second group of dimensionless variables, only consider the relationship between the maximum single-section charge amount, the distance from the blast center, the elevation difference, the effective influence radius, the change ratio of the elastic modulus of the surrounding rock, and the ground field coefficient to obtain the second relational expression.

[0042] Specifically, in this embodiment, based on the second group of dimensionless variables, when only considering the relationship between the maximum single-section charge amount, the distance from the blast center, the elevation difference, the effective influence radius, the change ratio of the elastic modulus of the surrounding rock, and the ground field coefficient, it can be obtained ​, it can be obtained from the acquisition method of the first relational expression that the second relational expression satisfies the following relationship: Among them, is the damage influence coefficient of the cumulative energy light explosion on the surrounding rock, is the influence coefficient related to the change ratio of the elastic modulus of the surrounding rock, r is the effective influence radius of the cumulative energy light explosion, is the change ratio of the elastic modulus of the surrounding rock.

[0043] S24. Obtain the second blasting vibration velocity prediction model according to the first blasting vibration velocity prediction model and the second relational expression.

[0044] Specifically, in this embodiment, the logarithmic form of the first blasting vibration velocity prediction model is the first relational expression. Obtaining the second blasting vibration velocity prediction model according to the first blasting vibration velocity prediction model and the second relational expression is to substitute the first relational expression into the second relational expression and simplify it, and then obtain the second blasting vibration velocity prediction model. The second blasting vibration velocity prediction model satisfies the following relationship: The second blasting vibration velocity prediction model further considers the influence of the damage effect of blasting on the surrounding rock structure on the vibration velocity on the basis of the first blasting vibration velocity prediction model, further improving the accuracy of the prediction of the blasting vibration velocity, and further improving the accuracy of the prediction of the blasting safety.

[0045] More specifically, , , , , and can be obtained through numerical simulation experiments using ANSYS / LS-DYNA numerical simulation software. First, use the numerical simulation software to construct a numerical model of the blasting target and set at least 12 vibration monitoring points. The blasting target refers to the tunnel where cumulative energy light explosion needs to be carried out, and the elevation differences between each vibration monitoring point and the blasting point are different. Then, carry out cumulative energy light explosion numerical simulation experiments under a set maximum single-section charge amount, record the in the cumulative energy light explosion numerical simulation experiments, and record the v, , , as well as of each vibration monitoring point and form an experimental data set. Finally, use Origin software to fit the data in the experimental data set to obtain a under , , , , and the values of. To quickly obtain the values of different under , , , , and , multiple different values of under , , , , and can be obtained through numerical simulation experiments, and then the change curves of , , , , and with respect to are respectively fitted, and then the change curves are used to quickly determine the values of , , , , and .

[0046] Furthermore, according to the description of step S1, when using the energy-gathering pipe cover for energy-gathering light blasting, multiple blast holes are usually provided, and there is a blasting delay between the blast holes. Therefore, by monitoring r and in the second blasting vibration velocity prediction model in real time, the blasting vibration velocity of each blast hole blasting vibration monitoring point can be accurately predicted, and then the blasting safety during energy-gathering light blasting can be accurately predicted.

[0047] S3. Use the second blasting vibration velocity prediction model to predict the blasting vibration velocity of the blasting point, and then judge the safety of the environment where the blasting point is located.

[0048] Among them, step S3 specifically includes the following steps: S31. Use the second blasting vibration velocity prediction model to predict the blasting vibration velocity of the vibration monitoring point, and record the prediction result as the vibration velocity prediction value.

[0049] Specifically, in this embodiment, the vibration monitoring points are set on the surrounding rock of the construction site where the blasting point is located, and the second blasting vibration velocity prediction model can be used to obtain the predicted value of the vibration velocity of the environment where the blasting point is located. For the convenience of subsequent description, this predicted value of the vibration velocity is denoted as the first predicted vibration velocity. In addition, since multi-hole delay blasting is used for blasting, multiple first predicted vibration velocities will be obtained, and the number of first predicted vibration velocities is the same as the number of blast holes.

[0050] Furthermore, the vibration monitoring points are set at the location of the ground building at the construction site where the blasting point is located, and the second blasting vibration velocity prediction model can be used to obtain the predicted value of the vibration velocity of the ground building. For the convenience of subsequent description, this predicted value of the vibration velocity is denoted as the second predicted vibration velocity, and the number of second predicted vibration velocities is the same as the number of blast holes.

[0051] S32. Compare the predicted value of the vibration velocity with the maximum allowable blasting vibration velocity of the environment where the blasting point is located, and then judge the safety of the environment where the blasting point is located.

[0052] Specifically, in this embodiment, the maximum allowable blasting vibration velocity of the environment where the blasting point is located is the maximum blasting vibration velocity allowed at the construction site where the blasting point is located. The maximum allowable blasting vibration velocity of the environment where the blasting point is located can be obtained by referring to relevant standards and specifications or through on-site investigation and evaluation.

[0053] More specifically, if all the first predicted vibration velocities are less than the maximum allowable blasting vibration velocity of the environment where the blasting point is located, it is considered that the environment where the blasting point is located is safe during blasting; otherwise, it is not safe.

[0054] S4. Predict the safety of the ground building according to the prediction result of the blasting vibration velocity of the blasting point by the second blasting vibration velocity prediction model.

[0055] Among them, step S4 specifically includes the following steps: S41. Construct an evaluation model for evaluating the safety of the ground building when tunneling blasting is carried out using a shaped charge pipe cover.

[0056] Specifically, in this step, although the second blasting vibration velocity prediction model can further improve the accuracy of predicting the blasting vibration velocity at the vibration monitoring point, it still does not fully consider all possible factors affecting the blasting vibration velocity. Therefore, there will always be a certain deviation in the predicted vibration velocity value calculated using the second blasting vibration velocity prediction model. In other words, the measured vibration velocity value obtained by detecting the blasting vibration velocity at the vibration monitoring point always falls near the predicted vibration velocity value. And as the accuracy of the predicted vibration velocity value increases, in multiple on-site shaped charge smooth blasting experiments on the blasting target, the probability that the measured vibration velocity value is far from the predicted vibration velocity value will decrease, and the probability of being close to the predicted vibration velocity value will increase. Therefore, based on the above analysis, in this embodiment, the blasting vibration velocity is considered to follow a normal distribution. Among them, the mean of the normal distribution described in this step is the second predicted vibration velocity value, and the variance is , where m is the number of on-site shaped charge smooth blasting experiments, is the measured vibration velocity value obtained from the j-th on-site shaped charge smooth blasting experiment, is the second predicted vibration velocity value calculated from the j-th on-site shaped charge smooth blasting experiment.

[0057] Furthermore, an evaluation model can be obtained according to the distribution function of the blasting vibration velocity. The evaluation model satisfies the following relationship: Among them, is the value of the safety index, n is the number of blast holes, is the predicted vibration velocity value caused by the blasting of the i-th blast hole, is the maximum allowable vibration velocity of the ground building, is the independent variable, is the standard deviation of the blasting vibration velocity. generally falls within the range of [0.2, 0.3], specifically, it can take 0.25 to avoid conducting on-site shaped charge smooth blasting experiments for different blasting targets. It should be noted that in this step, specifically refers to the second predicted vibration velocity value caused by the blasting of the i-th blast hole.

[0058] In this embodiment, using the value of the safety index can quantify the safety level of the ground building during shaped charge smooth blasting, and thus more intuitively reflect the safety of the ground building during shaped charge smooth blasting, and can improve the accuracy of predicting the blasting safety during shaped charge smooth blasting.

[0059] S42. Substitute the predicted vibration velocity value into the evaluation model, and then calculate the value of the safety index.

[0060] Specifically, in this embodiment, the second vibration speed prediction value is substituted into the evaluation model, and then the safety index value is calculated. The larger the safety index value is, the higher the safety of the ground building during blasting is, that is, the more difficult it is for blasting to damage the ground building.

[0061] It should be noted that in some cases, the actions described in the specification can be executed in a different order and still achieve the desired results. In this embodiment, the given step order is only for making the embodiment look clearer and more convenient for explanation, rather than a limitation.

[0062] In an alternative embodiment, please refer to Figure 2 , this embodiment also provides a blasting safety prediction system for tunneling blasting using a shaped charge pipe cover. The blasting safety prediction system for tunneling blasting using a shaped charge pipe cover includes: a data acquisition device 1, a data output device 2, a processor 3, and a storage 4. The storage 4 includes a computer-readable storage medium, and a computer program is stored in the computer-readable storage medium. The computer program includes program instructions, and when the program instructions are executed by the processor 3, the processor 3 implements the blasting safety prediction method for tunneling blasting using a shaped charge pipe cover provided by this embodiment.

[0063] Specifically, in this embodiment, the data acquisition device 1, the data output device 2, the processor 3, and the storage 4 are electrically connected to each other. Both the data acquisition device 1 and the data output device 2 include a digital display screen. Relevant personnel can input various parameters for calculating the vibration speed prediction value on the digital display screen of the data acquisition device 1, such as the lateral strain of the surrounding rock, the longitudinal strain of the surrounding rock, the longitudinal wave velocity, the explosive density, and the elevation difference. The data output device 2 can output the calculated vibration speed prediction value.

[0064] In summary, first, compared with the existing Sadovsky formula and its improved formulas, the present method first obtains the first blasting vibration velocity prediction model by introducing the elevation difference between the vibration monitoring point and the blasting point into the Sadovsky formula. Then, on the basis of the first blasting vibration velocity prediction model, the effective influence radius of shaped charge smooth blasting and the change ratio of the elastic modulus of surrounding rock are further introduced, thereby considering the damage effect of shaped charge smooth blasting on the surrounding rock, improving the accuracy of blasting vibration velocity prediction, and further improving the accuracy of blasting safety prediction. Second, compared with the blasting vibration velocity prediction method based on machine learning algorithms, the present method does not require a large number of blasting experiments to optimize the model after determining the second blasting vibration velocity prediction model, improving the efficiency of blasting safety prediction, and being beneficial to reducing engineering costs and safety risks. Finally, the present method constructs an evaluation model for safety evaluation of ground buildings, which can quantify the safety level of ground buildings during shaped charge smooth blasting, thereby more intuitively reflecting the safety of ground buildings during shaped charge smooth blasting, and improving the accuracy of blasting safety prediction during shaped charge smooth blasting. In addition, the system provided by the present invention not only has the advantages of the method provided by the present invention, but also can improve the efficiency of blasting safety prediction and the practicability of the present method.

[0065] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features. These modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered by the scope of the claims and the description of the present invention.

Claims

1. A method for predicting blasting safety using a shaped tube cover for tunneling blasting, characterized in that: The steps include: When using focused tube shroud for focused light blasting, based on dimensional analysis method, the Sadovsky formula is improved by considering terrain effect, and then the first blasting vibration velocity prediction model is obtained; Considering the destructive effect of blasting on the surrounding rock structure, the second blasting vibration velocity prediction model is obtained based on the dimensional analysis method and the first blasting vibration velocity prediction model; The second blasting vibration velocity prediction model is used to predict the blasting vibration velocity of the blasting point, and then the safety of the environment where the blasting point is located is judged; The safety of the ground building is predicted based on the prediction result of the blasting vibration velocity of the blasting point by the second blasting vibration velocity prediction model.

2. A method for predicting blasting safety using a shaped tube cover for tunneling blasting according to claim 1, characterized in that: When the focused light blasting is performed using the focused tube cover, the Sadovsky formula is improved based on the dimensional analysis method and the terrain effect is considered, and then the first blasting vibration velocity prediction model is obtained, which includes the following steps: Determine the basic dimensions for the dimensional analysis of the first blasting vibration and the physical quantities involved in the propagation of vibration waves during tunneling blasting using shaped tubes, taking into account the terrain effect; The first dimensional analysis of the blast vibration is carried out according to Buckingham's theorem, and the first set of dimensionless variables represented by π is obtained; Based on the first group of dimensionless variables, only the relationship between the maximum single-stage charge, the distance from the explosion center, the elevation difference and the ground field coefficient is considered, and the attenuation relationship between the ratio of the elevation difference to the distance from the explosion center and the blasting vibration velocity is considered to obtain the first relationship; Substituting Sadovsky's formula into the first relational expression and simplifying it, the first blasting vibration velocity prediction model is obtained.

3. A method for predicting blasting safety using a shaped tube cover for tunneling blasting according to claim 2, characterized in that: The first relational expression satisfies the following relationship: in, is the blasting vibration speed, is the site coefficient of the blasting point, is the terrain influence coefficient, is the attenuation coefficient, R is the distance from the explosion center, Q is the maximum single-stage charge, is the elevation influence coefficient, It is the elevation difference between the blasting point and the vibration monitoring point.

4. The method for predicting blasting safety using a shaped tube cover for tunneling blasting according to claim 2, characterized in that: The first blasting vibration velocity prediction model satisfies the following relationship: in, is the blasting vibration speed, is the site coefficient of the blasting point, is the terrain influence coefficient, is the attenuation coefficient, R is the distance from the explosion center, Q is the maximum single-stage charge, is the elevation influence coefficient, It is the elevation difference between the blasting point and the vibration monitoring point.

5. The method for predicting blasting safety using a shaped tube cover for tunneling blasting according to claim 2, characterized in that: The method of considering the destructive effect of blasting on the surrounding rock structure and obtaining the second blasting vibration velocity prediction model based on the dimensional analysis method and the first blasting vibration velocity prediction model comprises the following steps: Considering the destructive effect of blasting on the surrounding rock structure, the effective impact radius of focused light blasting and the change ratio of the elastic modulus of the surrounding rock are introduced, and then the dimensional analysis of the second blasting vibration is carried out; The second set of dimensionless variables represented by π is obtained by conducting the second dimensional analysis of the explosion vibration according to Buckingham's theorem; Based on the second group of dimensionless variables, only the relationship between the maximum single-stage charge, the distance from the explosion center, the elevation difference, the effective influence radius, the change ratio of the elastic modulus of the surrounding rock and the field coefficient is considered to obtain the second relationship; The second blasting vibration velocity prediction model is acquired according to the first blasting vibration velocity prediction model and the second relationship.

6. A method for predicting blasting safety using a shaped tube cover for tunneling blasting according to claim 5, characterized in that: The second relational expression satisfies the following relationship: in, is the blasting vibration speed, is the site coefficient of the blasting point, is the terrain influence coefficient, is the destructive influence coefficient of focused energy blast on surrounding rock, r is the effective influence radius of focused energy blast, is the change ratio of the elastic modulus of the surrounding rock, is the attenuation coefficient, R is the distance from the explosion center, Q is the maximum single-stage charge, is the elevation influence coefficient, is the influence coefficient related to the change ratio of the elastic modulus of the surrounding rock, It is the elevation difference between the blasting point and the vibration monitoring point.

7. A method for predicting blasting safety using a shaped tube cover for tunneling blasting according to claim 5, characterized in that: The second blasting vibration velocity prediction model satisfies the following relationship: in, is the blasting vibration speed, is the site coefficient of the blasting point, is the terrain influence coefficient, is the destructive influence coefficient of focused energy blast on surrounding rock, r is the effective influence radius of focused energy blast, is the change ratio of the elastic modulus of the surrounding rock, is the attenuation coefficient, R is the distance from the explosion center, Q is the maximum single-stage charge, is the elevation influence coefficient, is the influence coefficient related to the change ratio of the elastic modulus of the surrounding rock, It is the elevation difference between the blasting point and the vibration monitoring point.

8. The method for predicting blasting safety using a shaped tube cover for tunneling blasting according to claim 1, characterized in that: The method of using the second blasting vibration velocity prediction model to predict the blasting vibration velocity of the blasting point and then judging the safety of the environment where the blasting point is located comprises the following steps: The blasting vibration velocity prediction model is used to predict the blasting vibration velocity of the vibration monitoring point, and the prediction result is recorded as the vibration velocity prediction value; The vibration velocity prediction value is compared with the maximum allowable blasting vibration velocity of the environment where the blasting point is located, and then the safety of the environment where the blasting point is located is judged.

9. The method for predicting blasting safety using a shaped tube cover for tunneling blasting according to claim 1, characterized in that: The method of predicting the safety of the ground building according to the prediction result of the blasting vibration velocity of the blasting point by the second blasting vibration velocity prediction model comprises the following steps: An evaluation model for evaluating the safety of ground buildings when using a shaped tube cover for tunneling blasting is constructed, and the evaluation model satisfies the following relationship: in, is the safety index value, n is the number of blastholes, is the predicted value of the vibration velocity caused by the blasting of the i-th blasthole, is the maximum allowable vibration speed of the ground building, is the independent variable, is the standard deviation of the blasting vibration velocity; The vibration velocity prediction value is brought into the evaluation model to calculate the safety index value.

10. A blasting safety prediction system for tunneling blasting using a shaped tube cover, characterized in that: The blasting safety prediction system for tunneling blasting using a focused energy tube cover comprises: a data acquisition device, a data output device, a processor and a storage device, the storage device comprises a computer-readable storage medium, the computer-readable storage medium stores a computer program, the computer program comprises program instructions, and when the program instructions are executed by the processor, the processor implements the blasting safety prediction method for tunneling blasting using a focused energy tube cover as described in any one of claims 1 to 9.

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