Delay time simulation optimization method based on blasting effect and vibration

Abstract

The invention belongs to the technical field of blasting engineering, and particularly relates to a blasting effect and vibration-based delay time simulation optimization method, which is characterized by comprising the following steps of: 1, establishing a model; step 2, extracting vibration data; 3, blasting effect index extraction; and step 4, optimizing the delay time. According to the invention, superposition of vibration waves can be controlled through accurate delay time, and the purpose of vibration reduction is achieved; not only is the vibration reduction function considered, but also the blasting effect problem is considered, if the two parties have a contradiction point, the blasting effect is improved as much as possible on the basis of meeting the vibration requirement, and the goals of safety and high-quality production are achieved. Safety and quality are both considered, meanwhile, shock absorption holes or presplitting blasting and the like do not need to be punched by adopting traditional vibration reduction measures, the production efficiency can be greatly improved, and the production cost can be reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of blasting engineering, and in particular relates to a delay time simulation optimization method based on blasting effect and vibration. Background Art

[0002] Drilling and blasting is a necessary means of mining metal mines. The ore is blasted by drilling and blasting, and then a series of processes such as crushing and grinding are carried out to extract metals and other elements. With the improvement of residents' living standards and the enhancement of safety awareness, the harm caused by blasting vibration in blasting projects not only has an adverse impact on surrounding buildings, but also may cause conflicts with nearby residents, seriously affecting the progress of the project and causing economic losses.

[0003] As engineering blasting technology gradually develops towards refinement, and the environment of blasting projects becomes more and more complex, the requirements for blasting vibration are becoming more and more stringent. However, it is impossible to completely eliminate blasting vibration. The usual practice is to take effective control measures to reduce blasting vibration to the tolerable range of the protected objects. The "Safety Regulations for Blasting" (GB 6722-2014) divides the frequency of blasting vibration into several sections, and clearly stipulates the allowable vibration speed of various types of buildings in each frequency range. In some projects under certain specific environments, in order to consider the feelings of residents and ensure the smooth progress of the project, the requirements for blasting vibration during actual construction are more stringent. Due to the needs of production, it is necessary not only to control the blasting vibration within the allowable range, but also to meet the needs of production to ensure the blasting effect.

[0004] The existing patent (application number 201910765187.7) discloses a method for determining the delay time of adjacent rows of blast holes in micro-difference blasting. In open-air blasting, the optimal micro-difference time is calculated by measuring the frequency, wavelength, period, vibration speed, row spacing of adjacent rows of blast holes, and adjacent holes of the blasting seismic wave, but the influence of blasting vibration is not taken into account. The patent (application number 201811336765.7) discloses a method for reducing blasting vibration by precise delay blasting, but only considers the method and importance of vibration reduction, and does not make relevant evaluations on production quality. In order to find a method that can meet the requirements of blasting vibration within a reasonable range and production at the same time, it is particularly important to find a suitable delay time method. For this purpose, a delay time simulation optimization method based on blasting effect and vibration is proposed. Summary of the invention

[0005] The purpose of the present invention is to establish a delay time simulation optimization method that can achieve vibration reduction and take into account blasting effect by means of simulation, combined with relevant indicators and data of blasting effect and blasting vibration.

[0006] The objective of the present invention is achieved through the following technical solutions: The delay time simulation optimization method based on blasting effect and vibration of the present invention is characterized by comprising the following steps: Step 1: Model establishment; According to the blasting hole network parameters at the mine site, a three-dimensional model of bench blasting was established using the numerical simulation software ANSYS / LS-DYNA. The rock and explosive materials in the model are consistent with the actual ones on site.

[0007] Step 2: Extraction of vibration data; The blasting simulation calculation is carried out for different delay times between holes in the three-dimensional model of step blasting, and blasting vibration monitoring points are set at the same distance from the blastholes. At the same time, the peak vibration velocity data of the monitoring points are extracted and exported.

[0008] Step 3: Extraction of blasting effect indicators; Based on the numerical simulation software ANSYS / LS-DYNA, the blasting of different delay times of the steps is simulated and calculated. When the rock material unit cell reaches the limit of the damage stress it can withstand, the unit cell fails, thereby simulating the damage to the rock mass during the blasting process. The number of failed units is an indicator used to evaluate the blasting effect. When the number of failed units per cubic meter of rock mass reaches more than 50%, it means that the crack expansion is ideal and the overall crushing effect of the rock mass is good. Therefore, the number of failed units is used as an indicator to evaluate the blasting effect under different delay times.

[0009] Step 4: Optimization method for delay time.

[0010] Based on the current blasting equipment and blasting design experience, 30 groups of numerical simulation tests were carried out in the range of 11ms to 40ms with an interval of 1ms. The time history curve of the peak vibration velocity and the time history curve of the number of failure units were coupled to establish a peak vibration velocity-failure unit time history curve model. The peak vibration velocity-failure unit time history curve model under different delay times was compared. Combined with the vibration requirements in the "Safety Regulations for Blasting" (GB 6722-2014), the peak vibration velocity was controlled within the allowable range, the number of failure units was compared, and the delay time with the largest number of failure units was determined as the optimal delay time. When the number of failure units does not reach more than 50% within the allowable range of vibration velocity, it means that the blasting effect requirements cannot be met by adjusting the delay time alone, and other blasting design parameters such as hole network parameters and charge structure need to be coordinated and optimized.

[0011] Advantages of the present invention: (1) The delay time simulation optimization method based on blasting effect and vibration of the present invention can control the superposition of vibration waves through precise delay time to achieve the purpose of vibration reduction; (2) The delay time simulation optimization method based on blasting effect and vibration of the present invention not only simply considers the effect of vibration reduction, but also takes into account the blasting effect, thus achieving the goal of safe and high-quality production; (3) The delay time simulation optimization method based on blasting effect and vibration of the present invention takes into account both safety and quality. At the same time, it does not require the use of traditional vibration reduction measures such as drilling shock-absorbing holes or performing pre-splitting blasting, which can greatly improve production efficiency and reduce production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic diagram of the overall process of the present invention.

[0013] Figure 2 This is the peak vibration velocity time history diagram derived by the present invention.

[0014] Figure 3 This is a model diagram of the peak vibration velocity-failure unit time history curve of the present invention.

[0015] Figure 4 It is a schematic diagram of the simulation optimization method of the delay time of the present invention. DETAILED DESCRIPTION

[0016] The specific implementation of the present invention is further described below in conjunction with the accompanying drawings.

[0017] like Figure 1-4 As shown, a delay time simulation optimization method based on blasting effect and vibration of the present invention comprises the following steps: (1) Model establishment: For detailed steps of model establishment, see Figure 1 According to the parameters of the blasting hole network at the mine site, a three-dimensional model of bench blasting was established through the numerical simulation software ANSYS / LS-DYNA. The rock and explosive materials in the model are consistent with the actual situation on site.

[0018] (2) Extraction of vibration data: Taking 19ms, 20ms and 21ms delay time as examples, numerical simulation of blasting is carried out. Monitoring points are set up at the same distance from the blasthole, and the peak vibration velocity data of the monitoring points are extracted and exported. The peak vibration velocity data is as follows: Figure 2 As shown, the rules are basically the same, and there are certain differences in the peak value and the time to reach the peak value.

[0019] (3) Extraction of blasting effect indicators: Based on the numerical simulation software ANSYS / LS-DYNA, the cell failure occurs when the rock material unit reaches the limit of the damage stress it can withstand during the step delay blasting process, thereby simulating the damage to the rock mass during the blasting process. In the simulations with delay times of 19ms, 20ms, and 21ms, the number of failed units exceeds 50%, indicating that the overall rock mass crushing effect of the three delay times meets the requirements.

[0020] (4) Optimization method for delay time: The time history curve of the peak vibration velocity and the time history curve of the number of failed units are coupled to establish the peak vibration velocity-failed unit time history curve model as follows: Figure 3 As shown in the figure, the peak vibration velocity-failure unit time history curve model under different delay times is compared. Combined with the vibration requirements in the "Safety Regulations for Blasting" (GB 6722-2014), the peak vibration velocity is controlled within the range of 2.0cm / s-2.5cm / s, and the maximum failure unit is found. Figure 4 As shown in the figure, the simulation with a delay time of 21ms at the end of blasting meets the vibration requirements and obtains the maximum number of failed units among the three delay times, which is determined to be the optimal delay time. During the implementation of blasting operations, if there is a disagreement between the blasting unit and the regulatory agency or the surrounding affected units, we must adhere to the basic principle of meeting the vibration control requirements. Under this premise, a reasonable delay time should be selected to improve the quality of blasting operations as much as possible. Through this treatment method, not only the requirements of vibration control are successfully met, the safety of the surrounding environment and facilities is protected, but also the quality of blasting operations is greatly improved.

[0021] The delay time simulation optimization method based on blasting effect and vibration of the present invention can control the superposition of vibration waves through precise delay time to achieve the purpose of vibration reduction; the method not only simply considers vibration reduction, but also takes into account the blasting effect problem. At the same time, there is no need to adopt traditional vibration reduction measures such as drilling shock-absorbing holes or performing pre-splitting blasting, which can significantly improve production efficiency and reduce production costs.

Claims

1. A delay time simulation optimization method based on blasting effect and vibration, characterized in that: The following steps are involved: Step 1: Model establishment; Step 2: Extraction of vibration data; Step 3: Extraction of blasting effect indicators; Step 4: Optimization method for delay time; The optimization method for the delay time described in step 4 couples the time history curves of the peak vibration velocity and the number of failed units, establishes a peak vibration velocity-failure unit time history curve model, compares the time history curve model results under different delay times, and determines a reasonable delay time that takes into account blasting effect and vibration according to demand.

2. The delay time simulation optimization method based on blasting effect and vibration according to claim 1 is characterized in that: The model in step 1 is established based on the blasting hole network parameters at the mine site, and a three-dimensional model of bench blasting is established through the numerical simulation software ANSYS / LS-DYNA. The rock materials and explosive materials in the model are consistent with the actual on-site materials.

3. The delay time simulation optimization method based on blasting effect and vibration according to claim 1 is characterized in that: The vibration data is extracted in step 2, and simulations of multiple holes with different delay times are performed, and the peak vibration velocity data is monitored, extracted and exported at the same position.

4. The delay time simulation optimization method based on blasting effect and vibration according to claim 1 is characterized in that: The extraction of the blasting effect index in step 3 adopts the principle of failure criterion and uses the cell failure situation in the blasting simulation calculation as an index to evaluate the blasting effect.

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